Clinical outcomes of endovascular therapy for aortoiliac artery chronic total occlusion via the transradial approach

Clinical outcomes of endovascular therapy for aortoiliac artery chronic total occlusion via the transradial approach | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Clinical outcomes of endovascular therapy for aortoiliac artery chronic total occlusion via the transradial approach Naoki Hayakawa, Toshiki Tsurumaki, Hiromi Miwa, Yasuyuki Tsuchida, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7799822/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 13 Dec, 2025 Read the published version in CVIR Endovascular → Version 1 posted 4 You are reading this latest preprint version Abstract Background: Endovascular therapy (EVT) for the aortoiliac (AI) artery using the transradial approach (TRA) has become increasingly common with the availability of radial-specific devices. However, the feasibility of treating AI chronic total occlusion (CTO) via the TRA remains unclear. Methods: This was a single-center, retrospective study. From October 2019 to November 2024, among 105 cases of AI CTO treated with EVT, 46 procedures performed via the TRA were analyzed. The primary endpoint was clinical success. The secondary endpoints were 12-month freedom from clinically driven target lesion revascularization (CD-TLR), successful antegrade guidewire passage, procedure time, need for femoral sheath insertion, and procedural or perioperative complications. Results: The mean age was 74.4 ± 9.2 years. Mean lesion length was 121.9 ± 44.1 mm, and 80.4% were classified as Trans-Atlantic Inter-Society Consensus II type C/D. The left radial approach was used in 91.3% of cases. Stent implantation was successful in all patients. Bare nitinol stents were used in 78.3% and covered stents in 21.7%. Intravascular ultrasound was used in 97.8% of procedures. The TRA alone was performed in 34.8%, the TRA with sheathless femoral access in 13.0%, and femoral sheath insertion in 52.2%. The 12-month rate of freedom from CD-TLR was 94.7%. Mean procedure time was 97.2 ± 52.3 minutes. Successful antegrade guidewire passage was achieved in 56.5%. Procedural and perioperative complications each occurred in 6.6%. No cases of radial artery occlusion, cerebral infarction, or blue toe syndrome were observed. In the multivariable analysis, common-to-external iliac artery CTO (adjusted odds ratio 0.09, 95% confidence interval 0.02–0.53, p = 0.008) and common femoral artery involvement (adjusted odds ratio 0.05, 95% confidence interval 0.006–0.39, p = 0.005) were independently associated with unsuccessful antegrade guidewire passage. Conclusion: EVT for AI CTO via the TRA is feasible and achieves high procedural success; however, many cases required an additional bidirectional approach using the transfemoral route. Chronic total occlusion Endovascular therapy Transradial approach Intravascular ultrasound Aortoiliac artery Figures Figure 1 Figure 2 Background Endovascular therapy (EVT) for the aortoiliac (AI) region plays a pivotal role in the treatment of lower extremity artery disease and has become the first-line therapy for AI occlusive disease [ 1 , 2 ]. Traditionally, the transfemoral approach (TFA) has been the standard access site for EVT; however, puncture-related complications and the need for prolonged bed rest remain significant concerns [ 3 ]. By contrast, the transradial approach (TRA)—well established in coronary interventions for its safety and patient comfort—has recently been adopted for peripheral vascular interventions [ 4 , 5 ]. The TRA is associated with fewer bleeding complications, earlier ambulation, and improved patient satisfaction. Recent studies have shown that in the AI region, the TRA offers perioperative safety comparable to the TFA, while providing the added benefits of easier hemostasis and earlier mobilization [ 6 , 7 ]. Moreover, the TRA has been reported to result in shorter procedural times than the TFA [ 7 ]. Regarding long-term durability, Tsuchida et al. [ 8 ] recently reported favorable 3-year outcomes using the TRA-specific bare-nitinol stent Misago for AI lesions. Similarly, a multicenter study from Japan demonstrated that TRA stenting for iliac artery lesions was as safe and feasible as TFA, underscoring the clinical applicability of TRA in this vascular territory [ 9 ]. Nevertheless, several technical challenges persist in EVT for iliac arteries, particularly in complex chronic total occlusion (CTO) lesions [ 10 ]. These include insufficient device support, limited guidewire (GW) maneuverability, and difficulty delivering large-caliber devices. To address these limitations, a recent report demonstrated the safety and feasibility of a bidirectional strategy combining the TRA with sheathless femoral access, thereby compensating for the device support and reach limitations of the TRA [ 11 , 12 ]. Despite these advances, evidence specifically focused on iliac CTOs remains limited. In particular, which CTO cases can be successfully treated with the TRA alone and which require a bidirectional approach has not been fully clarified. Therefore, the aim of the present study was to evaluate the clinical outcomes of EVT for AI artery CTOs performed via TRA and to clarify its feasibility. Methods Study population and design This single-center, retrospective study was conducted at Asahi General Hospital. Between November 2019 and December 2024, a total of 2,527 patients underwent EVT at our institution. After excluding 2,029 patients treated for lesions outside the iliac artery, 33 patients with acute limb ischemia, 37 patients who underwent hemostasis-related procedures, and 323 patients with non-CTO lesions, 105 patients with AI CTO were identified for analysis. Of these, 59 patients treated with non-transradial approaches were excluded, leaving 46 patients with AI CTO treated via the TRA included in the final analysis (Fig. 1 ). The choice of TRA was determined at the discretion of each operator. Patients were excluded if the TRA was considered infeasible during pre-procedural assessment, defined as the absence of a palpable radial pulse, a radial artery (RA) diameter of less than 2 mm on ultrasound, or unsuitability as judged by the operator. The study protocol was approved by the local ethics committee of Asahi General Hospital and conducted in accordance with the Declaration of Helsinki. The requirement for informed consent was waived because of the retrospective design using existing medical records; however, patients were given the opportunity to opt out. Relevant study information was made publicly available in accordance with the Ethical Guidelines for Medical and Health Research Involving Human Subjects. Procedural protocol Two antithrombotic agents were administered at least 24 hours before the procedure. Aspirin, clopidogrel, or prasugrel was primarily used. In cases of allergy or previous bleeding events associated with these drugs, cilostazol was used as an alternative antiplatelet agent. Anticoagulants were prescribed when indicated, such as in patients with atrial fibrillation or other clinical needs. EVT was performed for AI CTO lesions. The primary access site was the RA, selected according to the pre-procedural feasibility assessment described above. When lesion crossing or device delivery was judged difficult with TRA alone, femoral puncture was performed to establish a bidirectional approach. The decision to insert a sheath or microcatheter from the femoral access, as well as the choice of sheath size, was made at the operator’s discretion based on lesion characteristics and procedural requirements. After sheath insertion into the RA and/or common femoral artery (CFA), 5,000 IU of unfractionated heparin was administered. When procedures were performed via the TRA, a Slender sheath with guiding catheter (Slenguide; Terumo Corp. Tokyo, Japan), a Destination Slender guiding sheath (Terumo Corp.), or a Parent 45 guiding sheath (Medikit Corp.) was used. Lesion crossing was attempted using a 0.014-, 0.018-, or 0.035-inch GW with a microcatheter or back-up support catheter. A bidirectional approach was adopted if conventional antegrade GW crossing failed. After successful GW passage, the balloon size for pre- and post-dilatation, as well as the type and diameter of stents, were determined based on quantitative vascular angiography and/or intravascular ultrasound (IVUS) evaluation. Stents were implanted from a healthy-to-healthy segment to ensure full coverage of the atherosclerotic lesion. Device selection—including the guiding sheath, GW, balloon catheter, and stent type—was left to the discretion of the treating operator. Procedural success was defined as successful recanalization of the target lesion with < 30% residual stenosis on final angiography. Hemostasis at the access site was achieved using either manual compression or a closure device, according to access route and operator preference. Study endpoints and definitions The primary endpoint of this study was clinical success, defined as < 30% residual stenosis without angiographic flow limitation. The secondary endpoints were the 12-month rate of freedom from clinically driven target lesion revascularization (CD-TLR), successful antegrade GW passage, procedure time, need for femoral sheath insertion, and procedural or perioperative complications. All procedures and clinical event assessments were conducted at our institution by at least three specialists certified by the Japanese Association of Cardiovascular Intervention and Therapeutics. Statistical analysis Statistical analyses were performed using JMP software version 13.0 (SAS Institute, Cary, NC, USA). Continuous variables are presented as mean ± standard deviation, and categorical variables are presented as count and percentage. A p value of < 0.05 was considered statistically significant, and 95% confidence intervals (CIs) are reported where appropriate. Differences in baseline characteristics among groups were tested using one-way analysis of variance for continuous variabilities and the chi-squared test for categorical variables. The rate of freedom from CD-TLR was estimated using the Kaplan–Meier method. The association between baseline characteristics and failure of antegrade GW passage was evaluated using a Cox proportional hazards regression model. Variables showing statistical significance in the univariable analysis were entered into the subsequent multivariable model. Results Baseline characteristics The patients’ clinical characteristics are summarized in Table 1 . In total, 46 patients who underwent EVT for AI CTO via the TRA were included in the analysis. Their mean age was 74.4 ± 9.2 years, and 39 patients (84.8%) were male. Twelve patients (26.1%) presented with chronic limb-threatening ischemia. The mean patient height was 161.2 ± 8.4 cm, and the mean body weight was 53.6 ± 11.4 kg. Ambulatory status was preserved in 91.3% of patients. Regarding comorbidities, hypertension was present in 78.3%, diabetes mellitus in 32.6%, and hemodialysis in 4.4% of patients. The mean number of treated lesions per patient was 2.2 ± 1.2. The most frequent lesion distribution was common iliac artery (CIA)–external iliac artery (EIA) (39.1%), followed by CIA alone (21.7%) and CIA–CFA (10.9%). The mean lesion length was 121.9 ± 44.1 mm. According to the Trans-Atlantic Inter-Society Consensus (TASC) II classification, 37 lesions (80.4%) were categorized as type C or D, indicating high lesion complexity. Preprocedural enhanced computed tomography (CT) was performed in 87.0% of patients, and a shaggy aorta was identified in 4.3%. A proximal blunt cap was observed in 56.5% of cases, while proximal calcification—defined as bilateral calcification at the proximal cap of the CTO, identified either on preprocedural CT or intra-procedural angiography—was present in 26.1%. Table 1 Patient and lesion characteristics Patient and lesion characteristics n = 46 Age, years 74.4 ± 9.2 Male 39 (84.8) CLTI 12 (26.1) Height, cm 161.2 ± 8.4 Weight, kg 53.6 ± 11.4 Ambulatory 42 (91.3) CAD 18 (39.1) CVD 17 (38.0) HT 36 (78.3) DL 26 (56.5) DM 15 (32.6) CKD 9 (19.6) HD 2 (4.4) Smoking 39 (84.8) Rutherford classification 3 31 (67.4) 4 3 (6.5) 5 11 (23.9) 6 1 (2.2) Number of treated lesions 2.2 ± 1.2 Aorta limited 0 (0.0) Aorta–CIA 2 (4.3) Aorta–EIA 2 (4.3) CIA 10 (21.7) CIA–EIA 18 (39.1) CIA–CFA 5 (10.9) EIA 6 (13.0) EIA–CFA 2 (4.3) Lesion length 121.9 ± 44.1 TASC II A 0 (0.0) B 9 (19.6) C 8 (17.4) D 29 (63.0) C/D 37 (80.4) Preprocedural enhanced CT 40 (87.0) Shaggy aorta 2 (4.3) Proximal cap blunt 26 (56.5) Proximal calcification 12 (26.1) Data are presented as mean ± standard deviation or n (%). CLTI, chronic limb-threatening ischemia; CAD, coronary artery disease; CVD, cerebrovascular disease; HT, hypertension; DM, diabetes mellitus; DL, dyslipidemia; CKD, chronic kidney disease; HD, hemodialysis; CIA, common iliac artery; EIA, external iliac artery; CFA, common femoral artery; TASC, Trans-Atlantic Inter-Society Consensus; CT, computed tomography Outcome measures The procedural outcomes are summarized in Table 2 . The left RA was the predominant access site, used in 91.3% of cases, while the right RA and distal RA were each used in 8.7%. The mean guiding sheath size was 6.0 ± 0.2 Fr. Femoral sheath insertion was performed in 52.2% of patients, and a bidirectional approach was required in 65.2%. In 13.0% of cases, a sheathless femoral technique was employed. IVUS was used in nearly all procedures (97.8%). Table 2 Procedure characteristics Lt RA 42 (91.3) Rt RA 4 (8.7) DRA 4 (8.7) Guiding sheath Fr 6.0 ± 0.2 Destination SL 36 (78.3) Slenguide 9 (19.6) Parent 45 1 (2.2) Femoral sheath insertion 24 (52.2) Bi-directional 30 (65.2) Sheathless femoral technique 6 (13.0) Support or diagnostic catheter use 26 (56.5) Micro catheter use 44 (95.7) IVUS use 45 (97.8) Subintimal involvement 2 (4.3) CTf3D-RM 29 (63.0) Antegrade wiring success 26 (56.5) Guidewire tip load, g 16.3 ± 19.4 Guidewires, n 2.7 ± 1.6 Guidewire crossing time, min 38.0 ± 42.1 Procedure time, min 97.2 ± 52.3 Stent use 46 (100) Stents, n 2.3 ± 1.2 Stent diameter, mm 9.0 ± 0.7 Stent length, mm 136.3 ± 48.8 Final device Misago 27 (58.7) SMART 3 (6.5) BNS only 36 (78.3) CS use 10 (21.7) CFA DCB use 10 (21.7) Data are presented as n (%) or mean ± standard deviation. Lt, left; Rt, right; RA, radial artery; DRA, distal radial artery; SL, Slender; IVUS, intravascular ultrasound; CTf3D-RM, computed tomography fusion three-dimensional roadmap; BNS, bare nitinol stent; CS, covered stent; CFA, common femoral artery; DCB, drug-coated balloon Antegrade GW passage was successful in 56.5% of cases. The mean GW tip load was 16.3 ± 19.4 g, and the mean number of GWs used per case was 2.7 ± 1.6. The mean GW crossing time was 38.0 ± 42.1 minutes, while the mean total procedure time was 97.2 ± 52.3 minutes. Stents were implanted in all patients (100%). The mean number of stents per patient was 2.3 ± 1.2, with a mean diameter of 9.0 ± 0.7 mm and a mean total stent length of 136.3 ± 48.8 mm. The Misago stent (Terumo Corp.) was the most frequently used device, implanted in 58.7% of cases. A balloon-expandable covered stent was used in 21.7%, and drug-coated balloon angioplasty for the CFA was performed in another 21.7%. The clinical outcomes are summarized in Table 3 . Clinical success was achieved in all 46 patients (100%). Procedural complications occurred in 6.6% of cases, including two cases of vessel perforation (4.3%) and one case of distal embolism (2.2%). All three were successfully managed with intra-procedural bailout measures, and none resulted in major postoperative adverse events. No puncture site complications, cerebral infarction, blue toe syndrome, or RA occlusion were observed (all 0%). Periprocedural complications occurred in three patients (6.6%), while non-procedural adverse events included urinary tract infection (2.2%), cerebral hemorrhage (2.2%), and death due to congestive heart failure (2.2%). Table 3 Clinical outcomes Clinical success 46 (100) Procedural complication 3 (6.6) Vessel perforation 2 (4.3) Distal embolism 1 (2.2) Periprocedural complication 3 (6.6) Puncture site complication 0 (0.0) Cerebral infarction 0 (0.0) Blue toe syndrome 0 (0.0) Radial artery occlusion 0 (0.0) UTI 1 (2.2) Cerebral hemorrhage 1 (2.2) Death due to CHF 1 (2.2) Time of bed rest, min 218.5 ± 155 Pre-ABI 0.52 ± 0.18 Post-ABI 0.99 ± 0.12 Follow up, days 576.5 (342.3–1031) Data are presented as n (%), mean ± standard deviation, or median (range). UTI, urinary tract infection; CHF, congestive heart failure; ABI, ankle–brachial index The mean bed rest time was 218.5 ± 155 minutes (less than 4 hours in most cases). The ankle-brachial index significantly improved from 0.52 ± 0.18 before EVT to 0.99 ± 0.12 after the procedure. At 12 months, the Kaplan–Meier estimate demonstrated a rate of freedom from CD-TLR of 96.9% (Fig. 2 ). Table 4 summarizes the risk factors for unsuccessful antegrade GW passage. In the univariable analysis, CIA–EIA occlusion (odds ratio [OR] 0.30, 95% CI 0.09–1.04, p = 0.07), lesion length of ≥ 125 mm (OR 0.21, 95% CI 0.06–0.75, p = 0.02), TASC II type C/D (OR 0.12, 95% CI 0.01–1.04, p = 0.06), and CFA involvement (OR 0.24, 95% CI 0.05–1.10, p = 0.08) were identified as potential predictors of failure in antegrade GW passage. In the multivariable analysis, CIA–EIA CTO (adjusted OR 0.09, 95% CI 0.02–0.53, p = 0.008) and CFA involvement (adjusted OR 0.05, 95% CI 0.006–0.39, p = 0.005) emerged as independent predictors of unsuccessful antegrade GW passage. These findings suggest that long CTOs and CFA involvement are key determinants of the need for a bidirectional strategy. Table 4 Predictors of antegrade guidewire passage Univariable analysis Multivariable analysis Odds ratio (95% CI) p value Odds ratio (95% CI) p value CFA involvement 0.24 (0.05–1.10) 0.08 0.05 (0.006–0.39) 0.005 CIA 4.0 (0.74–21.49) 0.15 CIA–EIA 0.30 (0.09–1.04) 0.07 0.09 (0.02–0.53) 0.008 CIA–CFA 0.16 (0.02–1.56) 0.15 EIA 4.52 (0.48–42.27) 0.21 CTf-3DRM 0.39 (0.11–1.39) 0.22 Lesion length ≥ 125 mm 0.21 (0.06–0.75) 0.02 TASC II C/D 0.12 (0.01–1.04) 0.06 Blunt type occlusion 1.12 (0.34–3.61) 1.00 Proximal calcification 0.44 (0.16–1.69) 0.31 0.19 (0.03–1.12) 0.07 Preprocedural CT 3.0 (0.49–18.36) 0.38 Ambulatory 4.41 (0.42–46.65) 0.30 CAD 0.94 (0.28–3.09) 1.00 CVD 0.79 (0.24–2.65) 0.76 HT 0.83 (0.20–3.47) 1.00 DM 0.55 (0.16–1.92) 0.53 DL 0.54 (0.16–1.78) 0.38 CKD 1.70 (0.37–7.85) 0.71 HD 0.76 (0.04–12.95) 1.00 Smoking 0.18 (0.02–1.60) 0.12 CI, confidence interval; CFA, common femoral artery; CIA, common iliac artery; EIA, external iliac artery; CTf-3DRM, computed tomography fusion three-dimensional roadmap; TASC, Trans-Atlantic Inter-Society Consensus; CT, computed tomography; CAD, coronary artery disease; CVD, cerebrovascular disease; HT, hypertension; DM, diabetes mellitus; DL, dyslipidemia; CKD, chronic kidney disease; HD, hemodialysis Discussion In this single-center study, we demonstrated that the TRA for EVT of AI CTO is both feasible and effective, achieving a high rate of clinical success with a low incidence of access site–related complications. Previous studies of the TRA for AI lesions have primarily focused on simpler cases, leaving its role in complex lesions such as CTO insufficiently defined [ 6 , 9 , 10 , 13 – 15 ]. The present findings suggest that EVT via the TRA is feasible when appropriate patient selection and technical adjustments are made. To our knowledge, no prior clinical study has focused exclusively on AI CTOs treated via the TRA while also examining both procedural feasibility and predictors of antegrade GW passage failure. Careful preprocedural assessment is essential for the safe and effective application of the TRA in CTO treatment. Cases that are generally considered challenging for transradial EVT include patients on hemodialysis and those with a type III aortic arch, a shaggy aorta, or marked aortic tortuosity. The reverse wire technique for type III arch anatomy and the distal RA approach in patients undergoing hemodialysis are reported strategies to overcome these difficulties; however, in the present study, the vast majority of procedures were performed via the RA, and only 4.4% of patients were on hemodialysis; therefore, the need for such techniques was limited [ 16 , 17 ]. In any case, careful preprocedural access evaluation—including CT imaging—remains crucial when planning the TRA for CTO interventions. Furthermore, the routine use of preprocedural CT imaging (87.0%) allowed detailed evaluation of proximal cap morphology, calcification, and overall lesion anatomy, which may have contributed to improved procedural efficiency and more informed access planning [ 18 ]. In cases approached via the RA, CT imaging also likely supported risk stratification for antegrade access and prediction of procedural difficulty. When anatomical factors such as aortic tortuosity suggested that an antegrade-only strategy would be challenging, femoral sheath insertion was likely considered from the outset. Importantly, our analysis identified specific lesion characteristics—namely CIA–EIA involvement and CFA inclusion—as independent predictors of unsuccessful antegrade GW passage. These findings suggest that while the TRA can be successfully applied in a considerable proportion of complex iliac lesions, patients with long CTOs, combined CIA–EIA occlusions, or CFA involvement may benefit from an upfront bidirectional strategy rather than attempting the TRA alone. A combined TRA and retrograde approach has been reported as an effective option for complex iliac lesions, with the retrograde route established either with or without a sheath [ 12 ]. Although IVUS was used in nearly all cases in this study, its efficacy in AI stenting has not always been clearly demonstrated in previous research [ 19 ]. However, those earlier studies included a broad spectrum of AI lesions—many of which were stenotic rather than totally occluded—and did not specifically address CTOs. In the context of CTOs, where GW crossing and accurate evaluation of lesion morphology, calcification, and vessel diameter are particularly challenging, the clinical value of IVUS may be especially significant. Indeed, prior studies have demonstrated the benefits of IVUS-guided EVT for complex AI occlusions [ 20 ]. In our cohort, despite the high lesion complexity—with more than 80% classified as TASC II type C/D—the high procedural success rate and relatively short procedure time may, at least in part, be attributable to the consistent use of IVUS. Bed rest time was remarkably short (< 4 hours in most patients), underscoring one of the major clinical advantages of the TRA compared with transfemoral access. Although more than half of the cases required a bidirectional approach, the relatively short bed rest duration may be explained by the fact that nearly 10% of patients underwent a sheathless femoral technique [ 12 ]. Even when a femoral sheath was used, hemostasis was often achieved intraoperatively using closure devices, in combination with balloon inflation from the TRA to temporarily occlude blood flow and facilitate hemostasis at the femoral puncture site. Although 65.2% of patients required a bidirectional approach, this strategy was not uniformly employed as a last resort following exhaustive antegrade wiring attempts. Rather, the decision to introduce femoral access was made at the operator’s discretion and often at an appropriate timing—before prolonged or excessive antegrade attempts. This likely contributed to the observation that both GW crossing time (38.0 ± 42.1 minutes) and total procedural time (97.2 ± 52.3 minutes) remained within acceptable limits despite the high lesion complexity. These findings suggest that timely transition to a bidirectional strategy was effective in maintaining both procedural efficiency and safety. Conversely, it is possible that if operators had persisted longer with the antegrade-only strategy, a greater number of cases might have achieved technical success without additional access. However, such an approach would likely have increased procedure time and the risk of complications. Thus, our results emphasize the importance of balancing persistence with antegrade strategies against the timely adoption of a bidirectional approach—tailored to lesion morphology, procedural progress, and overall patient safety. In the present study, the high procedural success rate was accompanied by a favorable rate of 1-year freedom from CD-TLR. Although the Misago stent was predominantly used, our findings align with the report by Tsuchida et al. [ 8 ], which demonstrated favorable outcomes of Misago stent implantation via the TRA in the AI segment. In addition, covered stents were employed in 21.7% of cases. Previous studies have reported excellent results with balloon-expandable covered stents in complex lesions [ 21 – 23 ]. With the growing availability of these devices for use via the TRA in recent years, EVT can now be performed even in more challenging situations, such as heavily calcified disease or long contiguous occlusions extending from the aorta—factors that may partly explain the favorable outcomes observed in this cohort. In this study, both intraprocedural and periprocedural complications were relatively infrequent. All intraprocedural complications were successfully managed with bailout strategies and did not adversely affect postoperative outcomes. For major complications such as vessel perforation or distal embolization, the expanded availability of covered stents via the TRA has increased therapeutic flexibility; nonetheless, it remains essential to employ the TFA without hesitation when complications arise. Furthermore, no cases of RA occlusion, periprocedural stroke, or access-site bleeding complications were observed—results that are even more favorable than those reported previously. Although the small sample size is a limitation, these findings may partly reflect careful preprocedural access evaluation and the predominant use of the left radial approach [ 5 , 6 , 9 ]. Limitations This study has several limitations. First, it was a single-center, retrospective, nonrandomized analysis with a relatively small sample size, which limits the generalizability of the results. Second, the choice of access strategy, timing of conversion to a bidirectional approach, and device selection (including the type of stent or covered stent) were left to the operator’s discretion, without a standardized protocol. Third, patient selection was based on operator judgment of RA feasibility, which may have introduced selection bias. Fourth, all angiographic findings, IVUS evaluations, and clinical outcomes were assessed on-site, without adjudication by an independent core laboratory or clinical events committee. Fifth, although IVUS was used in nearly all procedures, its interpretation and procedural contribution were not systematically analyzed, so its specific impact cannot be definitively determined. Finally, the relatively short follow-up period limits the ability to evaluate long-term patency and clinical durability beyond 12 months. Future prospective, multicenter studies with larger cohorts, standardized procedural protocols, and independent outcome adjudication are needed to validate these findings and further define the role of the TRA and bidirectional strategies in complex AI CTO interventions. Conclusions Our study has demonstrated that EVT for AI CTO using the TRA is feasible and achieves a high procedural success rate. Nevertheless, a substantial proportion of cases required the addition of a bidirectional approach with the TFA. Lesion characteristics—particularly long CTOs (> 125 mm) and CIA–EIA occlusion—were associated with antegrade failure, suggesting that a planned bidirectional strategy should be considered in such situations. Taken together, these findings support the concept that the TRA may serve as a first-line access option in selected patients with AI CTO, provided that lesion complexity and access planning are carefully assessed. Abbreviations EVT endovascular therapy AI aortoiliac TRA transradial approach CTO chronic total occlusion CD-TLR clinically driven target lesion revascularization TFA transfemoral approach GW guidewire RA radial artery CFA common femoral artery IVUS intravascular ultrasound Cis confidence intervals CIA common iliac artery EIA external iliac artery TASC Trans-Atlantic Inter-Society Consensus CT computed tomography Declarations Ethical approval and consent to participate: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional review board, independent ethics committee, or research ethics board applicable to each study site, and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Consent for publication: For this type of study, consent for publication is not required. Competing interests: NH received honoraria from Reflow Medical, Terumo, Kaneka Medics, Medicos Hirata, Boston Scientific, Medtronic, Abbott vascular, Cordis, and Becton, Dickinson and Company. The other authors report no conflicts of interest. Funding: No specific grants from any funding agency in the public, commercial, or not-for-profit sectors were received for this study. Authors’ contributions: NH is the corresponding author and wrote the paper. NH, HM, SI, SH, MA, and YI performed the procedures and pre- and post-procedure follow-ups. SK drafted the manuscript and revised it critically for important intellectual content. SK provided the final approval of the submitted manuscript. All authors read and approved the final manuscript. Acknowledgments: We thank Angela Morben, DVM, ELS, from Edanz ( https://jp.edanz.com/ac ), for editing a draft of this manuscript. Authors’ information : Not applicable. Availability of data and materials: The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request. References Soga Y, Iida O, Kawasaki D, Yamauchi Y, Suzuki K, Hirano K et al (2012) REAL-AI Investigators. Contemporary outcomes after endovascular treatment for aorto-iliac artery disease. Circ J 76(11):2697–2704 Yamauchi Y, Takahara M, Shintani Y, Iida O, Sugano T, Yamamoto Y et al (2019) OMOTENASHI Investigators. One-year outcomes of endovascular therapy for aortoiliac lesions. Circ Cardiovasc Interv 12(2):e007441 Ortiz D, Jahangir A, Singh M, Allaqaband S, Bajwa TK, Mewissen MW (2014) Access site complications after peripheral vascular interventions: incidence, predictors, and outcomes. Circ Cardiovasc Interv 7(6):821–828 Rao SV, Ou FS, Wang TY, Roe MT, Brindis R, Rumsfeld JS et al (2008) Trends in the prevalence and outcomes of radial and femoral approaches to percutaneous coronary intervention: A report from the National Cardiovascular Data Registry. JACC Cardiovasc Interv 1(4):379–386 Kwan TW, Patel VG, Banerjee S, Brilakis ES (2024) Radial artery access for peripheral vascular interventions: Current evidence and future directions. Ann Vasc Surg 96:34–42 Iida O, Takahara M, Fujihara M, Higashino N, Hayakawa N, Horie K et al (2024) COMFORT Investigators. Clinical outcomes of transradial vs nontransradial aortoiliac endovascular therapy. JACC Cardiovasc Interv 17(16):1891–1901 Horie K, Takahara M, Iida O, Kohsaka S, Nakama T, Shinke T et al (2025) Comparing the safety and feasibility of endovascular therapy via transradial and transfemoral approaches in patients with aortoiliac occlusive disease: A propensity score-matched analysis of the nationwide registry. J Endovasc Ther 32(3):756–765 Endo T, Saito K, Sakai S, Horiuchi D, Matsui H (2025) Comparison of procedural efficiency between transradial and transfemoral access in iliac artery EVT: A retrospective study. Cardiovasc Interv Ther. 10.1007/s12928-025-01182-x Epub ahead of print Tsuchida Y, Hayakawa N, Miwa H, Ichihara S, Maruta S, Kushida S (2025) Three-year clinical outcomes of the Misago stent via transradial intervention for aorto-iliac arterial disease. Heart Vessels. 10.1007/s00380-025-02562-2 Epub ahead of print Shinozaki N, Iwasaki Y, Doi H, Imoto Y, Ikari Y (2025) Results from a multicenter retrospective study of transradial iliac artery stenting in Japan. Cardiovasc Interv Ther 40(1):89–94 Lorenzoni R, Lisi C, Lorenzoni G, Tessandori L, Bovenzi F (2018) Endovascular treatment of iliac and common femoral arteries disease by the transradial access: A prospective, feasibility study. Cardiovasc Revasc Med 19(3 Pt B):314–318 Ruzsa Z, Tóth K, Nemes B, Édes IF, Nardai S, Berta B, Kovács N, Hüttl K, Merkely B (2016) Transradial and transulnar access for iliac artery interventions using sheathless guiding systems: A feasibility study. Catheter Cardiovasc Interv 88(6):923–931 Hayakawa N, Kodera S, Takanashi K, Ichihara S, Hirano S, Arakawa M et al (2022) Combining transradial access and sheathless femoral access for complex iliac artery chronic total occlusions. CVIR Endovasc 5(1):56 Shinozaki N, Minowa T, Murakami T, Ohno Y, Nakano M, Fujii T et al (2019) Slender transradial iliac artery stenting using a 4.5 French guiding sheath. Cardiovasc Interv Ther 34(1):9–13 Meertens MM, Ng E, Loh SEK, Samuel M, Mees BME, Choong AMTL (2018) Transradial approach for aortoiliac and femoropopliteal interventions: A systematic review and meta-analysis. J Endovasc Ther 25(5):599–607 Touma J, Coscas R, Javerliat I, Lamas H, Coggia M, Goëau-Brissonniere O (2016) Radial access for endovascular ilio-femoral procedures. J Cardiovasc Surg (Torino) 57(2):302–310 Yamazaki D, Matsumoto K, Yuzurihara M (2025) Transradial lower limb arteriography of the type III aortic arch: A reverse technique. Cureus 17(2):e78771 Shinozaki N, Ikari Y (2022) Distal radial artery approach for endovascular therapy. Cardiovasc Interv Ther 37(3):533–537 Hayakawa N, Kodera S, Ohki N, Sakkya S, Kanda J (2021) Efficacy of three-dimensional road mapping by fusion of computed tomography angiography and fluoroscopy in endovascular treatment of aorto-iliac chronic total occlusion. Heart Vessels 36(3):359–365 Tsujimura T, Takahara M, Iida O, Yamauchi Y, Shintani Y, Sugano T et al (2021) Intravascular ultrasound imaging during aortoiliac stenting: No impact on outcomes at 1 year. J Endovasc Ther 28(1):139–145 Pua U, Quek LHH, Yong E, Tan GWL (2020) Intravascular ultrasound-guided revascularization of chronic juxtarenal aortoiliac occlusion. Ann Vasc Surg 69:441–446 Mwipatayi BP, Sharma S, Daneshmand A, Thomas SD, Vijayan V, Altaf N et al (2016) COBEST co-investigators. Durability of the balloon-expandable covered versus bare-metal stents in the Covered versus Balloon Expandable Stent Trial (COBEST) for the treatment of aortoiliac occlusive disease. J Vasc Surg 64(1):83–94e1 Fujihara M, Takahara M, Yamaoka T, Iida O, Kojima T, Tobita K et al (2021) Clinical outcomes of endovascular procedure using VIABAHN® VBX covered stent in complex aortoiliac artery disease: Result from AVOCADO study. Catheter Cardiovasc Interv 98(5):928–937 Tomoi Y, Takahara M, Soga Y, Hata Y, Iida O, Yamaoka T et al (2023) AVOCADO II Investigators. Clinical outcome of endovascular therapy using a VIABAHN VBX-covered stent for complex aortoiliac artery disease: The AVOCADO II study. Heart Vessels 38(10):1288–1297 Cite Share Download PDF Status: Published Journal Publication published 13 Dec, 2025 Read the published version in CVIR Endovascular → Version 1 posted Reviewers agreed at journal 10 Oct, 2025 Reviewers invited by journal 10 Oct, 2025 Editor assigned by journal 10 Oct, 2025 First submitted to journal 07 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7799822","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":527747158,"identity":"ec86366b-5e6c-4529-afc8-51de08a745cb","order_by":0,"name":"Naoki 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1","display":"","copyAsset":false,"role":"figure","size":28900,"visible":true,"origin":"","legend":"\u003cp\u003eStudy flow chart.\u003c/p\u003e","description":"","filename":"OnlineFigure1.png","url":"https://assets-eu.researchsquare.com/files/rs-7799822/v1/390471fcfecc78c9bbb767d7.png"},{"id":94398981,"identity":"0a5e84db-77c5-4c0e-90e7-ebec031322c4","added_by":"auto","created_at":"2025-10-27 13:57:18","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":14379,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan–Meier curves of freedom from clinically driven target lesion revascularization.\u003c/p\u003e","description":"","filename":"OnlineFigure2.png","url":"https://assets-eu.researchsquare.com/files/rs-7799822/v1/aefc456668c535e1380e884a.png"},{"id":98245242,"identity":"bb270a67-d7c5-4e1f-a6e7-5e235cc3f8f2","added_by":"auto","created_at":"2025-12-15 16:17:18","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1140713,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7799822/v1/cdc89fef-d720-482c-875d-d3bafa90b4dd.pdf"}],"financialInterests":"","formattedTitle":"Clinical outcomes of endovascular therapy for aortoiliac artery chronic total occlusion via the transradial approach","fulltext":[{"header":"Background","content":"\u003cp\u003eEndovascular therapy (EVT) for the aortoiliac (AI) region plays a pivotal role in the treatment of lower extremity artery disease and has become the first-line therapy for AI occlusive disease [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Traditionally, the transfemoral approach (TFA) has been the standard access site for EVT; however, puncture-related complications and the need for prolonged bed rest remain significant concerns [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. By contrast, the transradial approach (TRA)\u0026mdash;well established in coronary interventions for its safety and patient comfort\u0026mdash;has recently been adopted for peripheral vascular interventions [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The TRA is associated with fewer bleeding complications, earlier ambulation, and improved patient satisfaction. Recent studies have shown that in the AI region, the TRA offers perioperative safety comparable to the TFA, while providing the added benefits of easier hemostasis and earlier mobilization [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Moreover, the TRA has been reported to result in shorter procedural times than the TFA [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Regarding long-term durability, Tsuchida et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e8\u003c/span\u003e] recently reported favorable 3-year outcomes using the TRA-specific bare-nitinol stent Misago for AI lesions. Similarly, a multicenter study from Japan demonstrated that TRA stenting for iliac artery lesions was as safe and feasible as TFA, underscoring the clinical applicability of TRA in this vascular territory [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eNevertheless, several technical challenges persist in EVT for iliac arteries, particularly in complex chronic total occlusion (CTO) lesions [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These include insufficient device support, limited guidewire (GW) maneuverability, and difficulty delivering large-caliber devices. To address these limitations, a recent report demonstrated the safety and feasibility of a bidirectional strategy combining the TRA with sheathless femoral access, thereby compensating for the device support and reach limitations of the TRA [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDespite these advances, evidence specifically focused on iliac CTOs remains limited. In particular, which CTO cases can be successfully treated with the TRA alone and which require a bidirectional approach has not been fully clarified. Therefore, the aim of the present study was to evaluate the clinical outcomes of EVT for AI artery CTOs performed via TRA and to clarify its feasibility.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy population and design\u003c/h2\u003e\u003cp\u003eThis single-center, retrospective study was conducted at Asahi General Hospital. Between November 2019 and December 2024, a total of 2,527 patients underwent EVT at our institution. After excluding 2,029 patients treated for lesions outside the iliac artery, 33 patients with acute limb ischemia, 37 patients who underwent hemostasis-related procedures, and 323 patients with non-CTO lesions, 105 patients with AI CTO were identified for analysis. Of these, 59 patients treated with non-transradial approaches were excluded, leaving 46 patients with AI CTO treated via the TRA included in the final analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe choice of TRA was determined at the discretion of each operator. Patients were excluded if the TRA was considered infeasible during pre-procedural assessment, defined as the absence of a palpable radial pulse, a radial artery (RA) diameter of less than 2 mm on ultrasound, or unsuitability as judged by the operator.\u003c/p\u003e\u003cp\u003e The study protocol was approved by the local ethics committee of Asahi General Hospital and conducted in accordance with the Declaration of Helsinki. The requirement for informed consent was waived because of the retrospective design using existing medical records; however, patients were given the opportunity to opt out. Relevant study information was made publicly available in accordance with the Ethical Guidelines for Medical and Health Research Involving Human Subjects.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eProcedural protocol\u003c/h3\u003e\n\u003cp\u003eTwo antithrombotic agents were administered at least 24 hours before the procedure. Aspirin, clopidogrel, or prasugrel was primarily used. In cases of allergy or previous bleeding events associated with these drugs, cilostazol was used as an alternative antiplatelet agent. Anticoagulants were prescribed when indicated, such as in patients with atrial fibrillation or other clinical needs.\u003c/p\u003e\u003cp\u003eEVT was performed for AI CTO lesions. The primary access site was the RA, selected according to the pre-procedural feasibility assessment described above. When lesion crossing or device delivery was judged difficult with TRA alone, femoral puncture was performed to establish a bidirectional approach. The decision to insert a sheath or microcatheter from the femoral access, as well as the choice of sheath size, was made at the operator\u0026rsquo;s discretion based on lesion characteristics and procedural requirements.\u003c/p\u003e\u003cp\u003eAfter sheath insertion into the RA and/or common femoral artery (CFA), 5,000 IU of unfractionated heparin was administered. When procedures were performed via the TRA, a Slender sheath with guiding catheter (Slenguide; Terumo Corp. Tokyo, Japan), a Destination Slender guiding sheath (Terumo Corp.), or a Parent 45 guiding sheath (Medikit Corp.) was used. Lesion crossing was attempted using a 0.014-, 0.018-, or 0.035-inch GW with a microcatheter or back-up support catheter. A bidirectional approach was adopted if conventional antegrade GW crossing failed. After successful GW passage, the balloon size for pre- and post-dilatation, as well as the type and diameter of stents, were determined based on quantitative vascular angiography and/or intravascular ultrasound (IVUS) evaluation. Stents were implanted from a healthy-to-healthy segment to ensure full coverage of the atherosclerotic lesion. Device selection\u0026mdash;including the guiding sheath, GW, balloon catheter, and stent type\u0026mdash;was left to the discretion of the treating operator.\u003c/p\u003e\u003cp\u003eProcedural success was defined as successful recanalization of the target lesion with \u0026lt;\u0026thinsp;30% residual stenosis on final angiography. Hemostasis at the access site was achieved using either manual compression or a closure device, according to access route and operator preference.\u003c/p\u003e\n\u003ch3\u003eStudy endpoints and definitions\u003c/h3\u003e\n\u003cp\u003eThe primary endpoint of this study was clinical success, defined as \u0026lt;\u0026thinsp;30% residual stenosis without angiographic flow limitation. The secondary endpoints were the 12-month rate of freedom from clinically driven target lesion revascularization (CD-TLR), successful antegrade GW passage, procedure time, need for femoral sheath insertion, and procedural or perioperative complications. All procedures and clinical event assessments were conducted at our institution by at least three specialists certified by the Japanese Association of Cardiovascular Intervention and Therapeutics.\u003c/p\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eStatistical analyses were performed using JMP software version 13.0 (SAS Institute, Cary, NC, USA). Continuous variables are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and categorical variables are presented as count and percentage. A \u003cem\u003ep\u003c/em\u003e value of \u0026lt;\u0026thinsp;0.05 was considered statistically significant, and 95% confidence intervals (CIs) are reported where appropriate. Differences in baseline characteristics among groups were tested using one-way analysis of variance for continuous variabilities and the chi-squared test for categorical variables. The rate of freedom from CD-TLR was estimated using the Kaplan\u0026ndash;Meier method. The association between baseline characteristics and failure of antegrade GW passage was evaluated using a Cox proportional hazards regression model. Variables showing statistical significance in the univariable analysis were entered into the subsequent multivariable model.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eBaseline characteristics\u003c/h2\u003e\u003cp\u003eThe patients\u0026rsquo; clinical characteristics are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. In total, 46 patients who underwent EVT for AI CTO via the TRA were included in the analysis. Their mean age was 74.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.2 years, and 39 patients (84.8%) were male. Twelve patients (26.1%) presented with chronic limb-threatening ischemia. The mean patient height was 161.2\u0026thinsp;\u0026plusmn;\u0026thinsp;8.4 cm, and the mean body weight was 53.6\u0026thinsp;\u0026plusmn;\u0026thinsp;11.4 kg. Ambulatory status was preserved in 91.3% of patients. Regarding comorbidities, hypertension was present in 78.3%, diabetes mellitus in 32.6%, and hemodialysis in 4.4% of patients. The mean number of treated lesions per patient was 2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2. The most frequent lesion distribution was common iliac artery (CIA)\u0026ndash;external iliac artery (EIA) (39.1%), followed by CIA alone (21.7%) and CIA\u0026ndash;CFA (10.9%). The mean lesion length was 121.9\u0026thinsp;\u0026plusmn;\u0026thinsp;44.1 mm. According to the Trans-Atlantic Inter-Society Consensus (TASC) II classification, 37 lesions (80.4%) were categorized as type C or D, indicating high lesion complexity. Preprocedural enhanced computed tomography (CT) was performed in 87.0% of patients, and a shaggy aorta was identified in 4.3%. A proximal blunt cap was observed in 56.5% of cases, while proximal calcification\u0026mdash;defined as bilateral calcification at the proximal cap of the CTO, identified either on preprocedural CT or intra-procedural angiography\u0026mdash;was present in 26.1%.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePatient and lesion characteristics\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePatient and lesion characteristics\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;46\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge, years\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e74.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e39 (84.8)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCLTI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12 (26.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHeight, cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e161.2\u0026thinsp;\u0026plusmn;\u0026thinsp;8.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWeight, kg\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e53.6\u0026thinsp;\u0026plusmn;\u0026thinsp;11.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAmbulatory\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e42 (91.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCAD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18 (39.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCVD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e17 (38.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHT\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36 (78.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e26 (56.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e15 (32.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCKD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9 (19.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSmoking\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e39 (84.8)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRutherford classification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31 (67.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3 (6.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e11 (23.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNumber of treated lesions\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAorta limited\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAorta\u0026ndash;CIA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAorta\u0026ndash;EIA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCIA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10 (21.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCIA\u0026ndash;EIA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18 (39.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCIA\u0026ndash;CFA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5 (10.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEIA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6 (13.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEIA\u0026ndash;CFA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLesion length\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e121.9\u0026thinsp;\u0026plusmn;\u0026thinsp;44.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTASC II\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9 (19.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8 (17.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29 (63.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eC/D\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e37 (80.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePreprocedural enhanced CT\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40 (87.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eShaggy aorta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProximal cap blunt\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e26 (56.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProximal calcification\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e12 (26.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eData are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation or n (%).\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eCLTI, chronic limb-threatening ischemia; CAD, coronary artery disease; CVD, cerebrovascular disease; HT, hypertension; DM, diabetes mellitus; DL, dyslipidemia; CKD, chronic kidney disease; HD, hemodialysis; CIA, common iliac artery; EIA, external iliac artery; CFA, common femoral artery; TASC, Trans-Atlantic Inter-Society Consensus; CT, computed tomography\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eOutcome measures\u003c/h3\u003e\n\u003cp\u003eThe procedural outcomes are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The left RA was the predominant access site, used in 91.3% of cases, while the right RA and distal RA were each used in 8.7%. The mean guiding sheath size was 6.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2 Fr. Femoral sheath insertion was performed in 52.2% of patients, and a bidirectional approach was required in 65.2%. In 13.0% of cases, a sheathless femoral technique was employed. IVUS was used in nearly all procedures (97.8%).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eProcedure characteristics\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLt RA\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e42 (91.3)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRt RA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4 (8.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDRA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4 (8.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGuiding sheath Fr\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDestination SL\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36 (78.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSlenguide\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9 (19.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParent 45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemoral sheath insertion\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e24 (52.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBi-directional\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e30 (65.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSheathless femoral technique\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6 (13.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSupport or diagnostic catheter use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e26 (56.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMicro catheter use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e44 (95.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIVUS use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e45 (97.8)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSubintimal involvement\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCTf3D-RM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e29 (63.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAntegrade wiring success\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e26 (56.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGuidewire tip load, g\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e16.3\u0026thinsp;\u0026plusmn;\u0026thinsp;19.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGuidewires, n\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGuidewire crossing time, min\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e38.0\u0026thinsp;\u0026plusmn;\u0026thinsp;42.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProcedure time, min\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e97.2\u0026thinsp;\u0026plusmn;\u0026thinsp;52.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStent use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e46 (100)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStents, n\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStent diameter, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStent length, mm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e136.3\u0026thinsp;\u0026plusmn;\u0026thinsp;48.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFinal device\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMisago\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e27 (58.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSMART\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3 (6.5)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBNS only\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36 (78.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCS use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10 (21.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCFA DCB use\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10 (21.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eData are presented as n (%) or mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eLt, left; Rt, right; RA, radial artery; DRA, distal radial artery; SL, Slender; IVUS, intravascular ultrasound; CTf3D-RM, computed tomography fusion three-dimensional roadmap; BNS, bare nitinol stent; CS, covered stent; CFA, common femoral artery; DCB, drug-coated balloon\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAntegrade GW passage was successful in 56.5% of cases. The mean GW tip load was 16.3\u0026thinsp;\u0026plusmn;\u0026thinsp;19.4 g, and the mean number of GWs used per case was 2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;1.6. The mean GW crossing time was 38.0\u0026thinsp;\u0026plusmn;\u0026thinsp;42.1 minutes, while the mean total procedure time was 97.2\u0026thinsp;\u0026plusmn;\u0026thinsp;52.3 minutes.\u003c/p\u003e\u003cp\u003eStents were implanted in all patients (100%). The mean number of stents per patient was 2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2, with a mean diameter of 9.0\u0026thinsp;\u0026plusmn;\u0026thinsp;0.7 mm and a mean total stent length of 136.3\u0026thinsp;\u0026plusmn;\u0026thinsp;48.8 mm. The Misago stent (Terumo Corp.) was the most frequently used device, implanted in 58.7% of cases. A balloon-expandable covered stent was used in 21.7%, and drug-coated balloon angioplasty for the CFA was performed in another 21.7%.\u003c/p\u003e\u003cp\u003eThe clinical outcomes are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Clinical success was achieved in all 46 patients (100%). Procedural complications occurred in 6.6% of cases, including two cases of vessel perforation (4.3%) and one case of distal embolism (2.2%). All three were successfully managed with intra-procedural bailout measures, and none resulted in major postoperative adverse events. No puncture site complications, cerebral infarction, blue toe syndrome, or RA occlusion were observed (all 0%). Periprocedural complications occurred in three patients (6.6%), while non-procedural adverse events included urinary tract infection (2.2%), cerebral hemorrhage (2.2%), and death due to congestive heart failure (2.2%).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eClinical outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eClinical success\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e46 (100)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProcedural complication\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3 (6.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVessel perforation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2 (4.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDistal embolism\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePeriprocedural complication\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3 (6.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePuncture site complication\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCerebral infarction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBlue toe syndrome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRadial artery occlusion\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0 (0.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eUTI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCerebral hemorrhage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDeath due to CHF\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1 (2.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTime of bed rest, min\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e218.5\u0026thinsp;\u0026plusmn;\u0026thinsp;155\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePre-ABI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePost-ABI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFollow up, days\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e576.5 (342.3\u0026ndash;1031)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eData are presented as n (%), mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, or median (range).\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"2\"\u003eUTI, urinary tract infection; CHF, congestive heart failure; ABI, ankle\u0026ndash;brachial index\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe mean bed rest time was 218.5\u0026thinsp;\u0026plusmn;\u0026thinsp;155 minutes (less than 4 hours in most cases). The ankle-brachial index significantly improved from 0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18 before EVT to 0.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 after the procedure.\u003c/p\u003e\u003cp\u003eAt 12 months, the Kaplan\u0026ndash;Meier estimate demonstrated a rate of freedom from CD-TLR of 96.9% (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e summarizes the risk factors for unsuccessful antegrade GW passage. In the univariable analysis, CIA\u0026ndash;EIA occlusion (odds ratio [OR] 0.30, 95% CI 0.09\u0026ndash;1.04, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.07), lesion length of \u0026ge;\u0026thinsp;125 mm (OR 0.21, 95% CI 0.06\u0026ndash;0.75, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02), TASC II type C/D (OR 0.12, 95% CI 0.01\u0026ndash;1.04, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.06), and CFA involvement (OR 0.24, 95% CI 0.05\u0026ndash;1.10, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.08) were identified as potential predictors of failure in antegrade GW passage. In the multivariable analysis, CIA\u0026ndash;EIA CTO (adjusted OR 0.09, 95% CI 0.02\u0026ndash;0.53, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.008) and CFA involvement (adjusted OR 0.05, 95% CI 0.006\u0026ndash;0.39, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.005) emerged as independent predictors of unsuccessful antegrade GW passage. These findings suggest that long CTOs and CFA involvement are key determinants of the need for a bidirectional strategy.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePredictors of antegrade guidewire passage\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eUnivariable analysis\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003eMultivariable analysis\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOdds ratio (95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eOdds ratio (95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003ep\u003c/em\u003e value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCFA involvement\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.24 (0.05\u0026ndash;1.10)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.08\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.05 (0.006\u0026ndash;0.39)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.005\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCIA\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e4.0 (0.74\u0026ndash;21.49)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.15\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCIA\u0026ndash;EIA\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.30 (0.09\u0026ndash;1.04)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.07\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.09 (0.02\u0026ndash;0.53)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCIA\u0026ndash;CFA\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.16 (0.02\u0026ndash;1.56)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.15\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eEIA\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e4.52 (0.48\u0026ndash;42.27)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.21\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCTf-3DRM\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.39 (0.11\u0026ndash;1.39)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.22\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eLesion length\u0026thinsp;\u0026ge;\u0026thinsp;125 mm\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.21 (0.06\u0026ndash;0.75)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.02\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eTASC II C/D\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.12 (0.01\u0026ndash;1.04)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.06\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eBlunt type occlusion\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e1.12 (0.34\u0026ndash;3.61)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e1.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eProximal calcification\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.44 (0.16\u0026ndash;1.69)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.31\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.19 (0.03\u0026ndash;1.12)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.07\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePreprocedural CT\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e3.0 (0.49\u0026ndash;18.36)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.38\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAmbulatory\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e4.41 (0.42\u0026ndash;46.65)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.30\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCAD\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.94 (0.28\u0026ndash;3.09)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e1.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCVD\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.79 (0.24\u0026ndash;2.65)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.76\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eHT\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.83 (0.20\u0026ndash;3.47)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e1.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDM\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.55 (0.16\u0026ndash;1.92)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.53\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDL\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.54 (0.16\u0026ndash;1.78)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.38\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCKD\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e1.70 (0.37\u0026ndash;7.85)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.71\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eHD\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.76 (0.04\u0026ndash;12.95)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e1.00\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSmoking\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.18 (0.02\u0026ndash;1.60)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.12\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eCI, confidence interval; CFA, common femoral artery; CIA, common iliac artery; EIA, external iliac artery; CTf-3DRM, computed tomography fusion three-dimensional roadmap; TASC, Trans-Atlantic Inter-Society Consensus; CT, computed tomography; CAD, coronary artery disease; CVD, cerebrovascular disease; HT, hypertension; DM, diabetes mellitus; DL, dyslipidemia; CKD, chronic kidney disease; HD, hemodialysis\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this single-center study, we demonstrated that the TRA for EVT of AI CTO is both feasible and effective, achieving a high rate of clinical success with a low incidence of access site–related complications. Previous studies of the TRA for AI lesions have primarily focused on simpler cases, leaving its role in complex lesions such as CTO insufficiently defined [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan additionalcitationids=\"CR14\" citationid=\"CR14\" class=\"CitationRef\"\u003e13\u003c/span\u003e–\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The present findings suggest that EVT via the TRA is feasible when appropriate patient selection and technical adjustments are made. To our knowledge, no prior clinical study has focused exclusively on AI CTOs treated via the TRA while also examining both procedural feasibility and predictors of antegrade GW passage failure.\u003c/p\u003e\u003cp\u003eCareful preprocedural assessment is essential for the safe and effective application of the TRA in CTO treatment. Cases that are generally considered challenging for transradial EVT include patients on hemodialysis and those with a type III aortic arch, a shaggy aorta, or marked aortic tortuosity. The reverse wire technique for type III arch anatomy and the distal RA approach in patients undergoing hemodialysis are reported strategies to overcome these difficulties; however, in the present study, the vast majority of procedures were performed via the RA, and only 4.4% of patients were on hemodialysis; therefore, the need for such techniques was limited [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In any case, careful preprocedural access evaluation—including CT imaging—remains crucial when planning the TRA for CTO interventions.\u003c/p\u003e\u003cp\u003eFurthermore, the routine use of preprocedural CT imaging (87.0%) allowed detailed evaluation of proximal cap morphology, calcification, and overall lesion anatomy, which may have contributed to improved procedural efficiency and more informed access planning [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In cases approached via the RA, CT imaging also likely supported risk stratification for antegrade access and prediction of procedural difficulty. When anatomical factors such as aortic tortuosity suggested that an antegrade-only strategy would be challenging, femoral sheath insertion was likely considered from the outset.\u003c/p\u003e\u003cp\u003eImportantly, our analysis identified specific lesion characteristics—namely CIA–EIA involvement and CFA inclusion—as independent predictors of unsuccessful antegrade GW passage. These findings suggest that while the TRA can be successfully applied in a considerable proportion of complex iliac lesions, patients with long CTOs, combined CIA–EIA occlusions, or CFA involvement may benefit from an upfront bidirectional strategy rather than attempting the TRA alone. A combined TRA and retrograde approach has been reported as an effective option for complex iliac lesions, with the retrograde route established either with or without a sheath [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eAlthough IVUS was used in nearly all cases in this study, its efficacy in AI stenting has not always been clearly demonstrated in previous research [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. However, those earlier studies included a broad spectrum of AI lesions—many of which were stenotic rather than totally occluded—and did not specifically address CTOs. In the context of CTOs, where GW crossing and accurate evaluation of lesion morphology, calcification, and vessel diameter are particularly challenging, the clinical value of IVUS may be especially significant. Indeed, prior studies have demonstrated the benefits of IVUS-guided EVT for complex AI occlusions [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. In our cohort, despite the high lesion complexity—with more than 80% classified as TASC II type C/D—the high procedural success rate and relatively short procedure time may, at least in part, be attributable to the consistent use of IVUS.\u003c/p\u003e\u003cp\u003eBed rest time was remarkably short (\u0026lt; 4 hours in most patients), underscoring one of the major clinical advantages of the TRA compared with transfemoral access. Although more than half of the cases required a bidirectional approach, the relatively short bed rest duration may be explained by the fact that nearly 10% of patients underwent a sheathless femoral technique [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Even when a femoral sheath was used, hemostasis was often achieved intraoperatively using closure devices, in combination with balloon inflation from the TRA to temporarily occlude blood flow and facilitate hemostasis at the femoral puncture site.\u003c/p\u003e\u003cp\u003eAlthough 65.2% of patients required a bidirectional approach, this strategy was not uniformly employed as a last resort following exhaustive antegrade wiring attempts. Rather, the decision to introduce femoral access was made at the operator’s discretion and often at an appropriate timing—before prolonged or excessive antegrade attempts. This likely contributed to the observation that both GW crossing time (38.0 ± 42.1 minutes) and total procedural time (97.2 ± 52.3 minutes) remained within acceptable limits despite the high lesion complexity. These findings suggest that timely transition to a bidirectional strategy was effective in maintaining both procedural efficiency and safety.\u003c/p\u003e\u003cp\u003eConversely, it is possible that if operators had persisted longer with the antegrade-only strategy, a greater number of cases might have achieved technical success without additional access. However, such an approach would likely have increased procedure time and the risk of complications. Thus, our results emphasize the importance of balancing persistence with antegrade strategies against the timely adoption of a bidirectional approach—tailored to lesion morphology, procedural progress, and overall patient safety.\u003c/p\u003e\u003cp\u003eIn the present study, the high procedural success rate was accompanied by a favorable rate of 1-year freedom from CD-TLR. Although the Misago stent was predominantly used, our findings align with the report by Tsuchida et al. [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e8\u003c/span\u003e], which demonstrated favorable outcomes of Misago stent implantation via the TRA in the AI segment. In addition, covered stents were employed in 21.7% of cases. Previous studies have reported excellent results with balloon-expandable covered stents in complex lesions [\u003cspan additionalcitationids=\"CR22\" citationid=\"CR22\" class=\"CitationRef\"\u003e21\u003c/span\u003e–\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. With the growing availability of these devices for use via the TRA in recent years, EVT can now be performed even in more challenging situations, such as heavily calcified disease or long contiguous occlusions extending from the aorta—factors that may partly explain the favorable outcomes observed in this cohort.\u003c/p\u003e\u003cp\u003eIn this study, both intraprocedural and periprocedural complications were relatively infrequent. All intraprocedural complications were successfully managed with bailout strategies and did not adversely affect postoperative outcomes. For major complications such as vessel perforation or distal embolization, the expanded availability of covered stents via the TRA has increased therapeutic flexibility; nonetheless, it remains essential to employ the TFA without hesitation when complications arise. Furthermore, no cases of RA occlusion, periprocedural stroke, or access-site bleeding complications were observed—results that are even more favorable than those reported previously. Although the small sample size is a limitation, these findings may partly reflect careful preprocedural access evaluation and the predominant use of the left radial approach [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e"},{"header":"Limitations","content":"\u003cp\u003eThis study has several limitations. First, it was a single-center, retrospective, nonrandomized analysis with a relatively small sample size, which limits the generalizability of the results. Second, the choice of access strategy, timing of conversion to a bidirectional approach, and device selection (including the type of stent or covered stent) were left to the operator’s discretion, without a standardized protocol. Third, patient selection was based on operator judgment of RA feasibility, which may have introduced selection bias. Fourth, all angiographic findings, IVUS evaluations, and clinical outcomes were assessed on-site, without adjudication by an independent core laboratory or clinical events committee. Fifth, although IVUS was used in nearly all procedures, its interpretation and procedural contribution were not systematically analyzed, so its specific impact cannot be definitively determined. Finally, the relatively short follow-up period limits the ability to evaluate long-term patency and clinical durability beyond 12 months. Future prospective, multicenter studies with larger cohorts, standardized procedural protocols, and independent outcome adjudication are needed to validate these findings and further define the role of the TRA and bidirectional strategies in complex AI CTO interventions.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eOur study has demonstrated that EVT for AI CTO using the TRA is feasible and achieves a high procedural success rate. Nevertheless, a substantial proportion of cases required the addition of a bidirectional approach with the TFA. Lesion characteristics\u0026mdash;particularly long CTOs (\u0026gt;\u0026thinsp;125 mm) and CIA\u0026ndash;EIA occlusion\u0026mdash;were associated with antegrade failure, suggesting that a planned bidirectional strategy should be considered in such situations. Taken together, these findings support the concept that the TRA may serve as a first-line access option in selected patients with AI CTO, provided that lesion complexity and access planning are carefully assessed.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eEVT\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eendovascular therapy\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eAI\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eaortoiliac\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eTRA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003etransradial approach\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCTO\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003echronic total occlusion\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCD-TLR\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eclinically driven target lesion revascularization\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eTFA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003etransfemoral approach\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eGW\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eguidewire\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eRA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eradial artery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCFA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ecommon femoral artery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eIVUS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eintravascular ultrasound\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCis\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003econfidence intervals\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCIA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ecommon iliac artery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eEIA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eexternal iliac artery\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eTASC\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eTrans-Atlantic Inter-Society Consensus\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCT\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ecomputed tomography\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate:\u003c/strong\u003e\u003cp\u003e All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional review board, independent ethics committee, or research ethics board applicable to each study site, and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication:\u003c/strong\u003e\u003cp\u003e For this type of study, consent for publication is not required.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eCompeting interests:\u003c/h2\u003e\u003cp\u003eNH received honoraria from Reflow Medical, Terumo, Kaneka Medics, Medicos Hirata, Boston Scientific, Medtronic, Abbott vascular, Cordis, and Becton, Dickinson and Company. The other authors report no conflicts of interest.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e\u003cp\u003eNo specific grants from any funding agency in the public, commercial, or not-for-profit sectors were received for this study.\u003c/p\u003e\u003ch2\u003eAuthors\u0026rsquo; contributions:\u003c/h2\u003e\u003cp\u003eNH is the corresponding author and wrote the paper. NH, HM, SI, SH, MA, and YI performed the procedures and pre- and post-procedure follow-ups. SK drafted the manuscript and revised it critically for important intellectual content. SK provided the final approval of the submitted manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgments:\u003c/h2\u003e\u003cp\u003eWe thank Angela Morben, DVM, ELS, from Edanz (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://jp.edanz.com/ac\u003c/span\u003e\u003cspan address=\"https://jp.edanz.com/ac\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e), for editing a draft of this manuscript.\u003c/p\u003e\u003cp\u003e\u003cb\u003eAuthors\u0026rsquo; information\u003c/b\u003e: Not applicable.\u003c/p\u003e\u003ch2\u003eAvailability of data and materials:\u003c/h2\u003e\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSoga Y, Iida O, Kawasaki D, Yamauchi Y, Suzuki K, Hirano K et al (2012) REAL-AI Investigators. Contemporary outcomes after endovascular treatment for aorto-iliac artery disease. Circ J 76(11):2697\u0026ndash;2704\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYamauchi Y, Takahara M, Shintani Y, Iida O, Sugano T, Yamamoto Y et al (2019) OMOTENASHI Investigators. One-year outcomes of endovascular therapy for aortoiliac lesions. Circ Cardiovasc Interv 12(2):e007441\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOrtiz D, Jahangir A, Singh M, Allaqaband S, Bajwa TK, Mewissen MW (2014) Access site complications after peripheral vascular interventions: incidence, predictors, and outcomes. Circ Cardiovasc Interv 7(6):821\u0026ndash;828\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRao SV, Ou FS, Wang TY, Roe MT, Brindis R, Rumsfeld JS et al (2008) Trends in the prevalence and outcomes of radial and femoral approaches to percutaneous coronary intervention: A report from the National Cardiovascular Data Registry. JACC Cardiovasc Interv 1(4):379\u0026ndash;386\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKwan TW, Patel VG, Banerjee S, Brilakis ES (2024) Radial artery access for peripheral vascular interventions: Current evidence and future directions. Ann Vasc Surg 96:34\u0026ndash;42\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eIida O, Takahara M, Fujihara M, Higashino N, Hayakawa N, Horie K et al (2024) COMFORT Investigators. Clinical outcomes of transradial vs nontransradial aortoiliac endovascular therapy. JACC Cardiovasc Interv 17(16):1891\u0026ndash;1901\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHorie K, Takahara M, Iida O, Kohsaka S, Nakama T, Shinke T et al (2025) Comparing the safety and feasibility of endovascular therapy via transradial and transfemoral approaches in patients with aortoiliac occlusive disease: A propensity score-matched analysis of the nationwide registry. J Endovasc Ther 32(3):756\u0026ndash;765\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eEndo T, Saito K, Sakai S, Horiuchi D, Matsui H (2025) Comparison of procedural efficiency between transradial and transfemoral access in iliac artery EVT: A retrospective study. Cardiovasc Interv Ther. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s12928-025-01182-x\u003c/span\u003e\u003cspan address=\"10.1007/s12928-025-01182-x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub ahead of print\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTsuchida Y, Hayakawa N, Miwa H, Ichihara S, Maruta S, Kushida S (2025) Three-year clinical outcomes of the Misago stent via transradial intervention for aorto-iliac arterial disease. Heart Vessels. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00380-025-02562-2\u003c/span\u003e\u003cspan address=\"10.1007/s00380-025-02562-2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub ahead of print\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShinozaki N, Iwasaki Y, Doi H, Imoto Y, Ikari Y (2025) Results from a multicenter retrospective study of transradial iliac artery stenting in Japan. Cardiovasc Interv Ther 40(1):89\u0026ndash;94\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLorenzoni R, Lisi C, Lorenzoni G, Tessandori L, Bovenzi F (2018) Endovascular treatment of iliac and common femoral arteries disease by the transradial access: A prospective, feasibility study. Cardiovasc Revasc Med 19(3 Pt B):314\u0026ndash;318\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRuzsa Z, T\u0026oacute;th K, Nemes B, \u0026Eacute;des IF, Nardai S, Berta B, Kov\u0026aacute;cs N, H\u0026uuml;ttl K, Merkely B (2016) Transradial and transulnar access for iliac artery interventions using sheathless guiding systems: A feasibility study. Catheter Cardiovasc Interv 88(6):923\u0026ndash;931\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHayakawa N, Kodera S, Takanashi K, Ichihara S, Hirano S, Arakawa M et al (2022) Combining transradial access and sheathless femoral access for complex iliac artery chronic total occlusions. CVIR Endovasc 5(1):56\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShinozaki N, Minowa T, Murakami T, Ohno Y, Nakano M, Fujii T et al (2019) Slender transradial iliac artery stenting using a 4.5 French guiding sheath. Cardiovasc Interv Ther 34(1):9\u0026ndash;13\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMeertens MM, Ng E, Loh SEK, Samuel M, Mees BME, Choong AMTL (2018) Transradial approach for aortoiliac and femoropopliteal interventions: A systematic review and meta-analysis. J Endovasc Ther 25(5):599\u0026ndash;607\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTouma J, Coscas R, Javerliat I, Lamas H, Coggia M, Go\u0026euml;au-Brissonniere O (2016) Radial access for endovascular ilio-femoral procedures. J Cardiovasc Surg (Torino) 57(2):302\u0026ndash;310\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYamazaki D, Matsumoto K, Yuzurihara M (2025) Transradial lower limb arteriography of the type III aortic arch: A reverse technique. Cureus 17(2):e78771\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShinozaki N, Ikari Y (2022) Distal radial artery approach for endovascular therapy. Cardiovasc Interv Ther 37(3):533\u0026ndash;537\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHayakawa N, Kodera S, Ohki N, Sakkya S, Kanda J (2021) Efficacy of three-dimensional road mapping by fusion of computed tomography angiography and fluoroscopy in endovascular treatment of aorto-iliac chronic total occlusion. Heart Vessels 36(3):359\u0026ndash;365\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTsujimura T, Takahara M, Iida O, Yamauchi Y, Shintani Y, Sugano T et al (2021) Intravascular ultrasound imaging during aortoiliac stenting: No impact on outcomes at 1 year. J Endovasc Ther 28(1):139\u0026ndash;145\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePua U, Quek LHH, Yong E, Tan GWL (2020) Intravascular ultrasound-guided revascularization of chronic juxtarenal aortoiliac occlusion. Ann Vasc Surg 69:441\u0026ndash;446\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMwipatayi BP, Sharma S, Daneshmand A, Thomas SD, Vijayan V, Altaf N et al (2016) COBEST co-investigators. Durability of the balloon-expandable covered versus bare-metal stents in the Covered versus Balloon Expandable Stent Trial (COBEST) for the treatment of aortoiliac occlusive disease. J Vasc Surg 64(1):83\u0026ndash;94e1\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eFujihara M, Takahara M, Yamaoka T, Iida O, Kojima T, Tobita K et al (2021) Clinical outcomes of endovascular procedure using VIABAHN\u0026reg; VBX covered stent in complex aortoiliac artery disease: Result from AVOCADO study. Catheter Cardiovasc Interv 98(5):928\u0026ndash;937\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTomoi Y, Takahara M, Soga Y, Hata Y, Iida O, Yamaoka T et al (2023) AVOCADO II Investigators. Clinical outcome of endovascular therapy using a VIABAHN VBX-covered stent for complex aortoiliac artery disease: The AVOCADO II study. Heart Vessels 38(10):1288\u0026ndash;1297\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"cvir-endovascular","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cire","sideBox":"Learn more about [CVIR Endovascular](https://www.springer.com/journal/42155)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/cire/default.aspx","title":"CVIR Endovascular","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Chronic total occlusion, Endovascular therapy, Transradial approach, Intravascular ultrasound, Aortoiliac artery","lastPublishedDoi":"10.21203/rs.3.rs-7799822/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7799822/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Endovascular therapy (EVT) for the aortoiliac (AI) artery using the transradial approach (TRA) has become increasingly common with the availability of radial-specific devices. However, the feasibility of treating AI chronic total occlusion (CTO) via the TRA remains unclear.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e This was a single-center, retrospective study. From October 2019 to November 2024, among 105 cases of AI CTO treated with EVT, 46 procedures performed via the TRA were analyzed. The primary endpoint was clinical success. The secondary endpoints were 12-month freedom from clinically driven target lesion revascularization (CD-TLR), successful antegrade guidewire passage, procedure time, need for femoral sheath insertion, and procedural or perioperative complications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The mean age was 74.4 ± 9.2 years. Mean lesion length was 121.9 ± 44.1 mm, and 80.4% were classified as Trans-Atlantic Inter-Society Consensus II type C/D. The left radial approach was used in 91.3% of cases. Stent implantation was successful in all patients. Bare nitinol stents were used in 78.3% and covered stents in 21.7%. Intravascular ultrasound was used in 97.8% of procedures. The TRA alone was performed in 34.8%, the TRA with sheathless femoral access in 13.0%, and femoral sheath insertion in 52.2%. The 12-month rate of freedom from CD-TLR was 94.7%. Mean procedure time was 97.2 ± 52.3 minutes. Successful antegrade guidewire passage was achieved in 56.5%. Procedural and perioperative complications each occurred in 6.6%. No cases of radial artery occlusion, cerebral infarction, or blue toe syndrome were observed. In the multivariable analysis, common-to-external iliac artery CTO (adjusted odds ratio 0.09, 95% confidence interval 0.02–0.53, \u003cem\u003ep\u003c/em\u003e = 0.008) and common femoral artery involvement (adjusted odds ratio 0.05, 95% confidence interval 0.006–0.39, \u003cem\u003ep\u003c/em\u003e= 0.005) were independently associated with unsuccessful antegrade guidewire passage.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e EVT for AI CTO via the TRA is feasible and achieves high procedural success; however, many cases required an additional bidirectional approach using the transfemoral route.\u003c/p\u003e","manuscriptTitle":"Clinical outcomes of endovascular therapy for aortoiliac artery chronic total occlusion via the transradial approach","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-26 00:41:58","doi":"10.21203/rs.3.rs-7799822/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2025-10-10T22:42:25+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-10T14:44:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-10T08:21:02+00:00","index":"","fulltext":""},{"type":"submitted","content":"CVIR Endovascular","date":"2025-10-07T09:07:13+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"cvir-endovascular","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cire","sideBox":"Learn more about [CVIR Endovascular](https://www.springer.com/journal/42155)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/cire/default.aspx","title":"CVIR Endovascular","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"dc22d72b-abe3-4a13-815e-8215a25f5924","owner":[],"postedDate":"October 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-15T16:13:30+00:00","versionOfRecord":{"articleIdentity":"rs-7799822","link":"https://doi.org/10.1186/s42155-025-00629-9","journal":{"identity":"cvir-endovascular","isVorOnly":false,"title":"CVIR Endovascular"},"publishedOn":"2025-12-13 15:57:53","publishedOnDateReadable":"December 13th, 2025"},"versionCreatedAt":"2025-10-26 00:41:58","video":"","vorDoi":"10.1186/s42155-025-00629-9","vorDoiUrl":"https://doi.org/10.1186/s42155-025-00629-9","workflowStages":[]},"version":"v1","identity":"rs-7799822","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7799822","identity":"rs-7799822","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}