Renal Artery Involvement as a Reliable Indicator of Severe Branch Vessel Involvement and Malperfusion in Type A Aortic Dissection

Renal Artery Involvement as a Reliable Indicator of Severe Branch Vessel Involvement and Malperfusion in Type A Aortic Dissection | 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 Renal Artery Involvement as a Reliable Indicator of Severe Branch Vessel Involvement and Malperfusion in Type A Aortic Dissection Ling-chen Huang, Li-xi Gan, MD, Si-yu Zhang, Ze-hua Shao, Yang-xue Sun, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5730684/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Reliable indicators to assess the severity and extent of type A aortic dissection (TAAD) remain lacking. This study aimed to evaluate the role of renal artery involvement in this context. Methods: From January 2020 to June 2022, a total of 471 patients with TAAD who underwent open surgical repair were retrospectively analyzed. Based on computed tomography angiography, patients were categorized into two groups: those with renal involvement (RAI, n=289) and those without (non-RAI, n=182). To further validate the results, propensity score matching (PSM) was performed to minimize bias. A multivariate ordered logistic regression model was used to evaluate the association between renal involvement and the number of end-organ malperfusion. The incidence of dialysis dependence was calculated using the Kaplan-Meier method. Cox regression models were utilized to determine factors of overall and mid-term mortality. Results: The RAI group exhibited more extensive aortic branch involvement (all P<0.05) and required more concomitant branch procedures, with a higher incidence of end-organ malperfusion (P=0.006), as well as increased serious adverse events (P=0.009), which remain consistent after PSM matching. The multivariate ordered logistic regression model indicated that renal involvement was associated with malperfusion [Odds ratio=2.00, 95% confidence interval (CI):1.25-3.27]. Multivariable Cox regression analysis identified renal involvement as an independent risk factor for overall mortality [hazard ratio (HR)=3.48, 95%CI:1.15-10.47, P=0.027] and mid-term mortality (HR=3.42, 95%CI:1.14-10.31, P=0.029). Kaplan-Meier analysis revealed no significant difference in dialysis dependence. Conclusions: Renal artery involvement signifies more severe aortic branch compromise and malperfusion, and worse prognosis. Renal artery involvement Type A aortic dissection Compromised aortic branch vessels Figures Figure 1 Figure 2 Summary Type of Research: Single-centre ambidirectional cohort study Key Findings: Renal artery involvement (RAI) in 471 patients with type A aortic dissection (TAAD) was associated with more extensive aortic branch compromise and a higher incidence of end-organ malperfusion (P=0.006) compared to patients without renal involvement (non-RAI). Take home Message: Renal artery involvement signifies more severe aortic branch compromise and malperfusion, and worse prognosis. Table of Contents Summary Renal artery involvement (RAI) significantly associated with the incidence of end-organ malperfusion and overall mortality in this retrospective analysis of 471 patients with type A aortic dissection undergoing surgical repair. Early detection of renal involvement may enable timely interventions to improve surgical outcomes. Introduction Type A aortic dissection (TAAD) is a complex, systemic condition in which the intimal tear can extend along the entire length of the aorta, potentially affecting multiple aortic branches and leading to end-organ ischemia and malperfusion 1 . Malperfusion, resulting from end-organ ischemia, is the most significant factor contributing to adverse outcomes, with a direct correlation between the number of organs involved and poor prognosis 2 , 3 . However, a reliable indicator to assess the severity and extent of TAAD has yet to be well established. Research efforts to develop image-based aortic markers could help identify high-risk conditions and provide a wealth of information for optimizing optimal clinical diagnosis and treatment strategies for these patients 4 . The renal artery, located downstream from the primary aortic branches, has received relatively little attention in studies related to TAAD. We hypothesize that renal artery involvement in TAAD correlates with the severity of aortic branch compromise, leading to significant malperfusion. The objective of this study is to classify TAAD patients based on the presence or absence of renal involvement, and to evaluate whether renal artery involvement could be a reliable indicator of the extent of TAAD-related compromise, and to evaluate its impact on malperfusion. Patients and Methods Ethics approval and consent to participate: The study was approved and monitored by the ethics committee of Fuwai Hospital, and individual consent was waived due to its retrospective nature. Patient population From January 2020 to June 2022, a total of 510 consecutive TAAD patients who underwent open surgical repair at our institution were included as the initial participants in this study. Patients who met any of the following exclusion criteria were not included in this study: (1) patients with renal atrophy or renal agenesis; (2) patients with severe renal artery stenosis; (3) patients with chronic kidney disease requiring ongoing treatment. Consequently, a total of thirty-nine patients were excluded. Among them, two patients with left renal atrophy, one patient with right renal agenesis, and two patients with severe stenosis of bilateral renal arteries were excluded. Renal involvement was defined as: intimal tear extending to the level of renal artery, with the renal artery being involved either with both true and false lumens or originating from the false lumen, as indicated by computed tomography angiography (CTA) images. The final study population consisted of 471 patients, of whom 289 had renal artery involvement (RAI group) and 182 did not have aortic dissection involving the renal artery (non-RAI group). Definition of adverse outcomes and study end-points All CTA images and clinical CTA reports were independently reviewed by two experienced cardiologists, and evaluated by an experienced radiologist when there was a discrepancy in diagnosis. Aortic branch involvement was defined in accordance with previous literature 1 . Malperfusion was defined as end-organ ischemia due to TAAD involving the corresponding aortic branch, caused by loss of blood supply to vital organs. Serious adverse events (SAEs) were defined as a composite of postoperative complications occurring during hospitalization, including operative mortality, stroke, or cardiac dysfunction requiring extracorporeal membrane oxygenation or intra-aortic balloon pump. Operative mortality was defined as death occurring during hospitalization or within 30-day after surgery. Midterm mortality was defined as all-cause mortality excluding operative mortality. Postoperative serum creatinine (SCr) and blood urea nitrogen (BUN) levels were collected sequentially over time. Data were recorded at three time points: immediately after surgery, the highest values within 48 hours postoperatively, and the highest values during hospitalization. Surgical Technique All TAAD patients were placed in the supine position. The procedure was performed under cardiopulmonary bypass (CPB) with arterial cannulation via the axillary and/or femoral arteries. The differences in surgical strategies for TAAD patients primarily lie in the methods of arch reconstruction, which are mainly divided into total arch reconstruction and hemi-arch replacement. For TAAD patients undergoing total aortic arch reconstruction at our institution, either total aortic arch replacement combined with frozen elephant trunk implantation or type II hybrid total arch repair was performed 5-8 . The detailed protocol of total arch replacement in combination with frozen elephant trunk implantation has been well described 5,6 . Selective cerebral perfusion was employed during periods of circulatory arrest to protect the brain from hypoxia and ischemia, with a perfusion flow rate maintained between 6-10 mL/kg/min. We routinely applied regional cerebral oxygen monitoring, with nasopharyngeal temperature maintained at 25-28°C. During the implantation of the elephant trunk stent and the anastomosis of the proximal end of the stent elephant trunk to the distal end of the four-branch artificial graft, circulation was arrested in the lower body and only cerebral perfusion was maintained. The Hybrid II procedure followed the protocol described in previous literature 6,7 , with nasopharyngeal temperature maintained at approximately 28°C. Commercially available covered stents for thoracic aortic pathologies were applied for endovascular stent grafting, with supra-aortic branches reconstruction. Similarly, for patients who underwent hemi-arch replacement, deep hypothermic circulatory arrest and cerebral perfusion also were not required. The main difference between the different strategies was whether the patient underwent selective cerebral perfusion and hypothermic lower body circulatory arrest. Follow-up Among hospital survivors, information about the health status of patients after discharge was obtained through annual outpatient revisit records or through telephone interviews to inquire about their postoperative recovery. Follow-up ended in July 2024. Statistical analysis All statistical analyses were conducted using R statistical software (version 4.3.1). A two-tailed p-value < 0.05 was considered statistically significant. Continuous variables were presented as mean ± standard deviation if normally distributed, and as median with interquartile range if not. Categorical variables were presented as frequency and percentage. To minimize baseline differences, propensity score matching (PSM) was performed using the following covariates: age, gender, body mass index, hypertension, diabetes, coronary artery disease, anticoagulant use, bicuspid aortic valve, preoperative left ventricular ejection fraction, and total bilirubin. Nearest-neighbor 1:1 matching without replacement, with a calliper width of 0.1, resulted in 150 matched pairs (300 patients). Continuous variables were compared using the independent t-test or Mann-Whitney U test, and categorical variables using the chi-squared (χ²) or Fisher’s exact test. Ordinal variables were analyzed with rank sum tests. After PSM, paired t-tests, Wilcoxon signed-rank tests, and McNemar tests were used. Multivariable ordered logistic regression was used to report proportional odds ratios and the probabilities of malperfusion (including cerebral, coronary, spinal cord, visceral malperfusion). Multivariable Cox proportional hazards models were employed to identify risk factors for overall survival and mid-term mortality, as well as life-long dialysis. Results Pre-operative demographic data are summarized in Table 1. Before PSM, significant differences were observed in baseline characteristics, including age, gender, body mass index, coronary artery disease, pericardial tamponade, and aortic valve regurgitation(p<.05). After PSM, these differences became non-significant (standardized mean difference < 10%), indicating successful matching (Figure 1). Regarding the characteristics of the renal and the aortic branch vessels (Table 2), 225 patients had left renal involvement, and 104 had right renal involvement. The RAI group had a significantly higher proportion of aortic branch involvement, including the right coronary artery, supra-aortic branches, celiac artery, mesenteric artery, and lower extremities, except for the left coronary artery, demonstrating statistical differences (all p<.05). In terms of malperfusion, the number of end-organ malperfusion showed significant differences (p=.006). Additionally, renal function in the RAI group was significantly worse compared to the non-RAI group, as evidenced by higher serum creatinine levels (90.65 μmol/L vs. 83.98 μmol/L, p=.004). These findings remained significant after PSM. Intra-operative data are detailed in Table 3. Surgical strategies for the aortic root and aortic arch did not significantly differ between the two groups. However, the RAI group underwent a higher proportion of aortic branch procedures (21.11% vs. 8.79%, p<0.001). Consequently, total operative time, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, and lower body circulatory time were longer for patients in RAI group before PSM. After PSM, significant differences persisted in operative time, CPB time, and circulatory arrest time. Early outcomes Early surgical outcomes, as outlined in Table 4, indicate favorable survival rates, with ten deaths during hospitalization. However, significant discrepancies emerged in SAEs, with 23 cases (7.96%) in the RAI group compared to 4 cases (2.20%) in the non-RAI group (P=0.009). Despite employing PSM to address baseline differences, the disparities persisted (10.00% vs. 2.00%, p=.004). Additionally, the incidence of post-operative dialysis was more frequently in the RAI group (11.07% vs. 3.30%, p=.003). In the RAI group, SCr levels at three postoperative time points, as well as immediate postoperative BUN levels, were elevated, along with prolonged intensive care unit stays, all demonstrating statistically significant differences. After PSM, these differences remained significant. The adjusted proportional ordered logistic regression model (covariates: age, gender, renal involvement) revealed that renal involvement was associated with a larger number of end-organ malperfusion [odds ratio 2.00, 95% confidence interval (CI):1.25-3.27, p=.005] in the adjusted model (Table S1). Follow-up The follow-up completion rate was 95.33%, with 22 patients and their families unreachable despite multiple attempts. The median follow-up time was 156 weeks (interquartile range: 124-184 weeks), with 11 recorded deaths among the surgical survivors. Preoperative renal artery involvement was identified as a significant risk factor for overall mortality in the multivariable Cox proportional hazards model [Hazard ratio (HR)=3.48, 95% CI: 1.15-10.47, p=0.027), as illustrated in Figure 2. It was also identified as risk factor for midterm mortality (HR=3.42, 95% CI: 1.14-10.31, p=0.029). The Kaplan-Meier method indicated no statistical difference in postoperative dialysis dependence across all surgical patients (log-rank p=.18) and among surgical survivors (log-rank p=.16) (Figure S1 A-B). Discussion This study revealed that renal artery involvement in TAAD indicates more severe and extensive aortic branch compromise and is associated with worse malperfusion. Additionally, renal involvement is linked to poorer short-term surgical outcomes and affects mid-term mortality but does not increase the risk of postoperative dialysis dependence during the follow-up period. TAAD frequently involves aortic branch vessels. Previous studies have highlighted that aortic branch involvement is a serious condition with significant potential for lethal end-organ malperfusion, which adversely affects clinical outcomes in patients with TAAD 1,9 . More extensive and severe branch vessel compromise is associated with worse clinical outcomes. Therefore, identifying a reliable indicator to evaluate the severity and extent of TAAD is crucial. Our study suggests that renal involvement has the potential to serve as a reliable indicator in this regard. Assessing the severity and extent of TAAD is challenging due to the complex morphology of the dissected aorta, and current indicators are inadequate. Existing classifications, such as the 301 and Fuwai classifications, are complex and difficult to apply, with limited validation 10,11 . We found that the aortic branches were more severely compromised in the RAI group, accompanied by greater end-organ malperfusion. This is attributed to the mechanisms of TAAD development, where high-velocity blood enters the intimal tear, creating a false lumen that expands under the impact of antegrade blood flow. Branch vessels divert and reduce the flow impact. When the false lumen expands and reaches the thoracoabdominal aorta at the level of the renal artery, it indicates a stronger blood flow impact 12 , signalling a greater extent of the intimal tear and more severe branch vessel compromise, which aligns with the CTA findings. Therefore, we conclude that the extent and severity of TAAD is greater when the renal artery is involved. Furthermore, as the operative outcomes indicated, the proportion of patients requiring combined branch procedures was higher in the RAI group, primarily due to more severe corresponding branch vessel compromise. Additionally, longer operation times resulted from combined branch procedures in the RAI group also reflect the higher severity of branch involvement. Overall, renal involvement is a straightforward and effective indicator for assessing the severity and extent of aortic branch compromise in TAAD. Our study reveals that TAAD patients with renal involvement had worse short-term surgical outcomes compared to those without renal involvement. This is primarily due to the fact that renal involvement indicates broader aortic branch involvement, often leading to increased end-organ malperfusion and complications, while also necessitating additional surgical interventions, thereby impacting surgical prognosis 13,14 . However, renal involvement does not equate to long-term renal injury. Postoperative dialysis dependence rates did not differ significantly. First, bilateral renal artery involvement is infrequent, and the compensatory function of the kidneys often mitigates the need for long-term dialysis. Second, acute kidney injury is often reversible; postoperative dialysis is usually caused by acute renal injury resulting from systemic factors such as pre-renal hypoperfusion, hypothermia, nephrotoxic drugs, or visceral ischemia. As a result, dialysis requirements usually decrease over time, as renal injury can often be detected early and intervened in promptly. Overall, renal artery involvement does not significantly increase the likelihood of lifelong dialysis dependence. We did not use SCr, or renal malperfusion as indicators, as elevated SCr levels are common in TAAD and can result from various factors, such as metabolic acidosis, adverse effects of hypothermic circulatory arrest, or hypotension caused by cardiac tamponade, which could not accurately reflect the extent of TAAD compromise branches vessel. Additionally, previous research has noted that “differential enhancement of the kidney as seen on the CTA is predictive, but not prescriptive for renal malperfusion” 15 limiting the value of renal malperfusion as indicators for the extent of TAAD compromise. Limitations Our study has some limitations, TAAD patients with more severe and extensive conditions may face a higher risk of death before surgery can be performed, potentially introducing Berkson’s bias in our cohort. Nevertheless, the study provides significant clinical value, offering a reliable indicator for identifying the extent and severity of TAAD. Conclusion Renal artery involvement in TAAD is a reliable indicator of more extensive and severe aortic branch compromise, strongly associated with end-organ malperfusion. Patients with renal involvement experience worse short-term surgical outcomes due to broader aortic branch vessel compromise. However, renal involvement does not increase the likelihood of postoperative dialysis dependence. Early detection of renal involvement may be beneficial for enabling timely intervention for compromised branch arteries, thereby mitigating the risks of malperfusion and improving surgical outcomes in TAAD patients. Abbreviations TAAD=type A aortic dissection CTA=computer tomograph angiography SAEs=Serious adverse events SCr=Serum creatinine BUN=Blood urea nitrogen PSM=Propensity score matching CPB=cardiopulmonary bypass Declarations Competing interests No competing interests. Funding statement No funding. Disclosures Availability of data and materials Data sharing was applicable from the first authors. The anonymous raw data that support the findings of this study are available from the first authors upon reasonable request and with permission of Fuwai hospital but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. The full R script for data wrangling and data analysis could be shared per reasonable request. Acknowledgements Long Deng, Dong Zhao et.al (Surgeons) served as excellent consultants for this article. To all colleagues we express our sincerely grateful and best wishes. References Yang B, Patel HJ, Williams DM, Dasika NL, Deeb GM. Management of type A dissection with malperfusion. Ann Cardiothorac Surg. 2016;5(4):265-274. Norton EL, Khaja MS, Williams DM, Yang B. Type A aortic dissection complicated by malperfusion syndrome. Curr Opin Cardiol. 2019;34(6):610-615. Berretta P, Trimarchi S, Patel HJ, Gleason TG, Eagle KA, Di Eusanio M. Malperfusion syndromes in type A aortic dissection: what we have learned from IRAD. J Vis Surg. 2018;4:65. Published 2018 Mar 31. Isselbacher EM, Preventza O, Hamilton Black J 3rd, et al. 2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines. Circulation. 2022;146(24):e334-e482. Liu ZG, Sun LZ, Chang Q, et al. Should the "elephant trunk" be skeletonized? Total arch replacement combined with stented elephant trunk implantation for Stanford type A aortic dissection. J Thorac Cardiovasc Surg. 2006;131(1):107-113. Sun L, Qi R, Chang Q, et al. Surgery for marfan patients with acute type a dissection using a stented elephant trunk procedure. Ann Thorac Surg. 2008;86(6):1821-1825. Chang Q, Tian C, Wei Y, Qian X, Sun X, Yu C. Hybrid total arch repair without deep hypothermic circulatory arrest for acute type A aortic dissection (R1). J Thorac Cardiovasc Surg. 2013;146(6):1393-1398. Zhang L, Yu C, Yang X, et al. Hybrid and frozen elephant trunk for total arch replacement in DeBakey type I dissection. J Thorac Cardiovasc Surg. 2019;158(5):1285-1292. Czerny M, Schoenhoff F, Etz C, et al. The Impact of Pre-Operative Malperfusion on Outcome in Acute Type A Aortic Dissection: Results From the GERAADA Registry. J Am Coll Cardiol. 2015;65(24):2628-2635. Ge YY, Rong D, Ge XH, et al. The 301 Classification: A Proposed Modification to the Stanford Type B Aortic Dissection Classification for Thoracic Endovascular Aortic Repair Prognostication. Mayo Clin Proc. 2020;95(7):1329-1341. Qiu J, Luo X, Wu J, et al. A New Aortic Arch Dissection Classification: The Fuwai Classification. Front Cardiovasc Med. 2021;8:710281. Published 2021 Sep 14. Mikich B. Dissection of the aorta: a new approach [published correction appears in Heart. 2003 Mar;89(3):328. Mikich M [corrected to Mikich B]]. Heart. 2003;89(1):6-8. Matalanis G, Ip S. Total aortic repair for acute type A aortic dissection: a new paradigm. J Vis Surg. 2018;4:79. Published 2018 Apr 26. Yang B, Rosati CM, Norton EL, et al. Endovascular Fenestration/Stenting First Followed by Delayed Open Aortic Repair for Acute Type A Aortic Dissection With Malperfusion Syndrome. Circulation. 2018;138(19):2091-2103. van Bakel PAJ, Henry M, Kim KM, et al. Imaging features of renal malperfusion in aortic dissection. Eur J Cardiothorac Surg. 2022;61(4):805-813. Tables Tables 1 to 4 are available in the Supplementary Files section Additional Declarations The authors declare no competing interests. Supplementary Files Table.docx Tables SupplementalFigure1A.jpg Figure S1. Kaplan–Meier survival curves for postoperative dialysis dependence in two groups: A. Dialysis among all surgical patients. SupplementalFigure1B.jpg Figure S1. Kaplan–Meier survival curves for postoperative dialysis dependence in two groups: B. Chronic dialysis among surgical survivors. 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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-5730684","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":395491663,"identity":"932f54aa-0f81-4619-b710-dad402c6ad7e","order_by":0,"name":"Ling-chen Huang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ling-chen","middleName":"","lastName":"Huang","suffix":""},{"id":395491664,"identity":"c1a957d4-db5f-4ecf-842b-a8fd9803f8cb","order_by":1,"name":"Li-xi Gan, MD","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Li-xi","middleName":"","lastName":"Gan","suffix":"MD"},{"id":395491665,"identity":"d198496c-f488-4557-9f7f-50407fc8cf87","order_by":2,"name":"Si-yu Zhang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Si-yu","middleName":"","lastName":"Zhang","suffix":""},{"id":395491666,"identity":"c3e19662-c57a-4a89-b614-75d967c50daf","order_by":3,"name":"Ze-hua Shao","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Ze-hua","middleName":"","lastName":"Shao","suffix":""},{"id":395491667,"identity":"541af93e-b57e-428f-9bc5-2bd56c624204","order_by":4,"name":"Yang-xue Sun","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yang-xue","middleName":"","lastName":"Sun","suffix":""},{"id":395491668,"identity":"d9f44144-718b-42c5-9047-14c920c78604","order_by":5,"name":"Yuan-rui Gu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Yuan-rui","middleName":"","lastName":"Gu","suffix":""},{"id":395491669,"identity":"97ab3407-030a-4bc5-b91d-68532fde20be","order_by":6,"name":"Xiang-yang Qian","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xiang-yang","middleName":"","lastName":"Qian","suffix":""},{"id":395491670,"identity":"096f47d6-b79c-4a6d-aefe-f23da495a71e","order_by":7,"name":"Xiao-gang Sun","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Xiao-gang","middleName":"","lastName":"Sun","suffix":""},{"id":395491671,"identity":"ffd708b9-903d-41f6-8bbc-2cf185578fa0","order_by":8,"name":"Cun-tao Yu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Cun-tao","middleName":"","lastName":"Yu","suffix":""},{"id":395491672,"identity":"da9721a5-32dc-4116-b3f2-75719ab553c9","order_by":9,"name":"Hong Liu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Hong","middleName":"","lastName":"Liu","suffix":""},{"id":395491673,"identity":"15f4eab5-48a7-47b0-a165-cf855f338cbe","order_by":10,"name":"Hongwei Guo","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAoUlEQVRIiWNgGAWjYDACCRCqYOAhVcsZkrUwtpHiLvnoHsPblfPqZMzZDzB++JhDhBbDO2eMLc9uO8xj2ZPALDlzGzFaZuRuk2zcdoDH4EACGzMv8Vrm1PEYnH9ApBZ5CZCWBmYegxvE2mIgkf/ZsuHYYaCWh83E+UV+RlrizYaaOnuD88kHP3wkypYDcCZjAxHqQbYQqW4UjIJRMApGMgAAGD40gtOPv44AAAAASUVORK5CYII=","orcid":"","institution":"","correspondingAuthor":true,"prefix":"","firstName":"Hongwei","middleName":"","lastName":"Guo","suffix":""}],"badges":[],"createdAt":"2024-12-29 15:27:52","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-5730684/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5730684/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":72738961,"identity":"59d8d2fc-89a5-4be7-a7fb-3f8b5c79bf8c","added_by":"auto","created_at":"2025-01-01 09:22:57","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":869570,"visible":true,"origin":"","legend":"\u003cp\u003eAll variables have an SMD \u0026lt; 0.1, indicating well baseline matching.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/713265adf66ca662f3726dcd.jpg"},{"id":72738631,"identity":"bcf219ac-99b8-4cbf-b0ae-1d9368574d33","added_by":"auto","created_at":"2025-01-01 09:14:57","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":555006,"visible":true,"origin":"","legend":"\u003cp\u003eForest plot shows the risk factors for all-cause mortality in patients received surgical by multivariable Cox proportional hazards model.\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/00743c9da138a330e941032c.jpg"},{"id":72740353,"identity":"fcac15b9-da08-4d90-bded-6086842522e8","added_by":"auto","created_at":"2025-01-01 09:30:57","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1802214,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/8629188c-d230-4cd2-8781-cbe1ac86e742.pdf"},{"id":72738957,"identity":"d9520e6a-d170-4c9e-8187-4d5897322595","added_by":"auto","created_at":"2025-01-01 09:22:57","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":43389,"visible":true,"origin":"","legend":"\u003cp\u003eTables\u003c/p\u003e","description":"","filename":"Table.docx","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/c59e7f0b1c24cc444223fcc7.docx"},{"id":72738628,"identity":"b03f9929-4ef3-45a8-a11e-1c96c94c87d9","added_by":"auto","created_at":"2025-01-01 09:14:57","extension":"jpg","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":613536,"visible":true,"origin":"","legend":"\u003cp\u003eFigure S1. Kaplan–Meier survival curves for postoperative dialysis dependence in two groups: A. Dialysis among all surgical patients.\u003c/p\u003e","description":"","filename":"SupplementalFigure1A.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/ddde7aeaa13b4bdff1c6195f.jpg"},{"id":72738635,"identity":"74065c4f-5e13-4d2d-98ea-d35cb7f9b204","added_by":"auto","created_at":"2025-01-01 09:14:57","extension":"jpg","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":613988,"visible":true,"origin":"","legend":"\u003cp\u003eFigure S1. Kaplan–Meier survival curves for postoperative dialysis dependence in two groups: B. Chronic dialysis among surgical survivors.\u003c/p\u003e","description":"","filename":"SupplementalFigure1B.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/9728c465992389e7d352043e.jpg"},{"id":72738636,"identity":"1e6fe6ec-621e-427c-abc4-7e52660263fc","added_by":"auto","created_at":"2025-01-01 09:14:57","extension":"jpg","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":2264656,"visible":true,"origin":"","legend":"\u003cp\u003eGraphical abstract: Overview of the study, created by FiGDRAW.\u003c/p\u003e","description":"","filename":"Graphicalabstract.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5730684/v1/00130fb485862c5e5a81e9b0.jpg"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eRenal Artery Involvement as a Reliable Indicator of Severe Branch Vessel Involvement and Malperfusion in Type A Aortic Dissection\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Summary","content":"\u003cp\u003e\u003cstrong\u003eType of Research:\u0026nbsp;\u003c/strong\u003eSingle-centre ambidirectional cohort study\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eKey Findings:\u0026nbsp;\u003c/strong\u003eRenal artery involvement (RAI) in 471 patients with type A aortic dissection (TAAD) was associated with more extensive aortic branch compromise and a higher incidence of end-organ malperfusion (P=0.006) compared to patients without renal involvement (non-RAI).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTake home Message:\u0026nbsp;\u003c/strong\u003eRenal artery involvement signifies more severe aortic branch compromise and malperfusion, and worse prognosis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable of Contents Summary\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRenal artery involvement (RAI) significantly associated with the incidence of end-organ malperfusion and overall mortality in this retrospective analysis of 471 patients with type A aortic dissection undergoing surgical repair. Early detection of renal involvement may enable timely interventions to improve surgical outcomes.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eType A aortic dissection (TAAD) is a complex, systemic condition in which the intimal tear can extend along the entire length of the aorta, potentially affecting multiple aortic branches and leading to end-organ ischemia and malperfusion\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Malperfusion, resulting from end-organ ischemia, is the most significant factor contributing to adverse outcomes, with a direct correlation between the number of organs involved and poor prognosis\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. However, a reliable indicator to assess the severity and extent of TAAD has yet to be well established.\u003c/p\u003e \u003cp\u003eResearch efforts to develop image-based aortic markers could help identify high-risk conditions and provide a wealth of information for optimizing optimal clinical diagnosis and treatment strategies for these patients\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. The renal artery, located downstream from the primary aortic branches, has received relatively little attention in studies related to TAAD. We hypothesize that renal artery involvement in TAAD correlates with the severity of aortic branch compromise, leading to significant malperfusion. The objective of this study is to classify TAAD patients based on the presence or absence of renal involvement, and to evaluate whether renal artery involvement could be a reliable indicator of the extent of TAAD-related compromise, and to evaluate its impact on malperfusion.\u003c/p\u003e"},{"header":"Patients and Methods","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eThe study was approved and monitored by the ethics committee of Fuwai Hospital, and individual consent was waived due to its retrospective nature.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient population\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFrom January 2020 to June 2022, a total of 510 consecutive TAAD patients who underwent open surgical repair at our institution were included as the initial participants in this study. Patients who met any of the following exclusion criteria were not included in this study: (1) patients with renal atrophy or renal agenesis; (2) patients with severe renal artery stenosis; (3) patients with chronic kidney disease requiring ongoing treatment. Consequently, a total of thirty-nine patients were excluded. Among them, two patients with left renal atrophy, one patient with right renal agenesis, and two patients with severe stenosis of bilateral renal arteries were excluded. Renal involvement was defined as: intimal tear extending to the level of renal artery, with the renal artery being involved either with both true and false lumens or originating from the false lumen, as indicated by computed tomography angiography (CTA) images. The final study population consisted of 471 patients, of whom 289 had renal artery involvement (RAI group) and 182 did not have aortic dissection involving the renal artery (non-RAI group).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDefinition of adverse outcomes and study end-points\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll CTA images and clinical CTA reports were independently reviewed by two experienced cardiologists, and evaluated by an experienced radiologist when there was a discrepancy in diagnosis. Aortic branch involvement was defined in accordance with previous literature\u003csup\u003e1\u003c/sup\u003e. Malperfusion was defined as end-organ ischemia due to TAAD involving the corresponding aortic branch, caused by loss of blood supply to vital organs. Serious adverse events (SAEs) were defined as a composite of postoperative complications occurring during hospitalization, including operative mortality, stroke, or cardiac dysfunction requiring extracorporeal membrane oxygenation or intra-aortic balloon pump. Operative mortality was defined as death occurring during hospitalization or within 30-day after surgery. Midterm mortality was defined as all-cause mortality excluding operative mortality.\u003c/p\u003e\n\u003cp\u003ePostoperative serum creatinine (SCr) and blood urea nitrogen (BUN) levels were collected sequentially over time. Data were recorded at three time points: immediately after surgery, the highest values within 48 hours postoperatively, and the highest values during hospitalization.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSurgical Technique\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll TAAD patients were placed in the supine position. The procedure was performed under cardiopulmonary bypass (CPB) with arterial cannulation via the axillary and/or femoral arteries. The differences in surgical strategies for TAAD patients primarily lie in the methods of arch reconstruction, which are mainly divided into total arch reconstruction and hemi-arch replacement.\u003c/p\u003e\n\u003cp\u003eFor TAAD patients undergoing total aortic arch reconstruction at our institution, either total aortic arch replacement combined with frozen elephant trunk implantation or type II hybrid total arch repair was performed\u003csup\u003e5-8\u003c/sup\u003e. The detailed protocol of total arch replacement in combination with frozen elephant trunk implantation has been well described\u003csup\u003e5,6\u003c/sup\u003e. Selective cerebral perfusion was employed during periods of circulatory arrest to protect the brain from hypoxia and ischemia, with a perfusion flow rate maintained between 6-10 mL/kg/min. We routinely applied regional cerebral oxygen monitoring, with nasopharyngeal temperature maintained at 25-28°C. During the implantation of the elephant trunk stent and the anastomosis of the proximal end of the stent elephant trunk to the distal end of the four-branch artificial graft, circulation was arrested in the lower body and only cerebral perfusion was maintained.\u003c/p\u003e\n\u003cp\u003eThe Hybrid II procedure followed the protocol described in previous literature\u003csup\u003e6,7\u003c/sup\u003e, with nasopharyngeal temperature maintained at approximately 28°C. Commercially available covered stents for thoracic aortic pathologies were applied for endovascular stent grafting, with supra-aortic branches reconstruction. Similarly, for patients who underwent hemi-arch replacement, deep hypothermic circulatory arrest and cerebral perfusion also were not required. The main difference between the different strategies was whether the patient underwent selective cerebral perfusion and hypothermic lower body circulatory arrest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFollow-up\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAmong hospital survivors, information about the health status of patients after discharge was obtained through annual outpatient revisit records or through telephone interviews to inquire about their postoperative recovery. Follow-up ended in July 2024.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll statistical analyses were conducted using R statistical software (version 4.3.1). A two-tailed p-value \u0026lt; 0.05 was considered statistically significant. Continuous variables were presented as mean ± standard deviation if normally distributed, and as median with interquartile range if not. Categorical variables were presented as frequency and percentage.\u003c/p\u003e\n\u003cp\u003eTo minimize baseline differences, propensity score matching (PSM) was performed using the following covariates: age, gender, body mass index, hypertension, diabetes, coronary artery disease, anticoagulant use, bicuspid aortic valve, preoperative left ventricular ejection fraction, and total bilirubin. Nearest-neighbor 1:1 matching without replacement, with a calliper width of 0.1, resulted in 150 matched pairs (300 patients).\u003c/p\u003e\n\u003cp\u003eContinuous variables were compared using the independent t-test or Mann-Whitney U test, and categorical variables using the chi-squared (χ²) or Fisher’s exact test. Ordinal variables were analyzed with rank sum tests. After PSM, paired t-tests, Wilcoxon signed-rank tests, and McNemar tests were used. Multivariable ordered logistic regression was used to report proportional odds ratios and the probabilities of malperfusion (including cerebral, coronary, spinal cord, visceral malperfusion). Multivariable Cox proportional hazards models were employed to identify risk factors for overall survival and mid-term mortality, as well as life-long dialysis.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003ePre-operative demographic data are summarized in Table 1. Before PSM, significant differences were observed in baseline characteristics, including age, gender, body mass index, coronary artery disease, pericardial tamponade, and aortic valve regurgitation(p\u0026lt;.05). After PSM, these differences became non-significant (standardized mean difference \u0026lt; 10%), indicating successful matching (Figure 1).\u003c/p\u003e\n\u003cp\u003eRegarding the characteristics of the renal and the aortic branch vessels (Table 2), 225 patients had left renal involvement, and 104 had right renal involvement. The RAI group had a significantly higher proportion of aortic branch involvement, including the right coronary artery, supra-aortic branches, celiac artery, mesenteric artery, and lower extremities, except for the left coronary artery, demonstrating statistical differences (all p\u0026lt;.05). In terms of malperfusion, the number of end-organ malperfusion showed significant differences (p=.006). Additionally, renal function in the RAI group was significantly worse compared to the non-RAI group, as evidenced by higher serum creatinine levels (90.65\u0026nbsp;\u0026mu;mol/L vs. 83.98\u0026nbsp;\u0026mu;mol/L, p=.004). These findings remained significant after PSM.\u003c/p\u003e\n\u003cp\u003eIntra-operative data are detailed in Table 3.\u0026nbsp;Surgical strategies for the aortic root and aortic arch did not significantly differ between the two groups. However, the RAI group underwent a higher proportion of aortic branch procedures (21.11% vs. 8.79%, p\u0026lt;0.001). Consequently, total operative time, cardiopulmonary bypass (CPB) time, aortic cross-clamp time, and lower body circulatory time were longer for patients in RAI group before PSM. After PSM, significant differences persisted in operative time, CPB time, and circulatory arrest time.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEarly outcomes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEarly surgical outcomes, as outlined in Table 4, indicate favorable survival rates, with ten deaths during hospitalization. However, significant discrepancies emerged in SAEs, with 23 cases (7.96%) in the RAI group compared to 4 cases (2.20%) in the non-RAI group (P=0.009). Despite employing PSM to address baseline differences, the disparities persisted (10.00% vs. 2.00%, p=.004). Additionally, the incidence of post-operative dialysis was more frequently in the RAI group (11.07% vs. 3.30%, p=.003). In the RAI group, SCr levels at three postoperative time points, as well as immediate postoperative BUN levels, were elevated, along with prolonged intensive care unit stays, all demonstrating statistically significant differences. After PSM, these differences remained significant.\u003c/p\u003e\n\u003cp\u003eThe adjusted proportional ordered logistic regression model (covariates: age, gender, renal involvement) revealed that renal involvement was associated with a larger number of end-organ malperfusion [odds ratio 2.00, 95% confidence interval (CI):1.25-3.27, p=.005] in the adjusted model (Table S1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFollow-up\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe follow-up completion rate was 95.33%, with 22 patients and their families unreachable despite multiple attempts. The median follow-up time was 156 weeks (interquartile range: 124-184 weeks), with 11 recorded deaths among the surgical survivors. Preoperative renal artery involvement was identified as a significant risk factor for overall mortality in the multivariable Cox proportional hazards model [Hazard ratio (HR)=3.48, 95% CI: 1.15-10.47, p=0.027), as illustrated in Figure 2. It was also identified as risk factor for midterm mortality (HR=3.42, 95% CI: 1.14-10.31, p=0.029). The Kaplan-Meier method indicated no statistical difference in postoperative dialysis dependence across all surgical patients (log-rank p=.18) and among surgical survivors (log-rank p=.16) (Figure S1 A-B).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study revealed that renal artery involvement in TAAD indicates more severe and extensive aortic branch compromise and is associated with worse malperfusion. Additionally, renal involvement is linked to poorer short-term surgical outcomes and affects mid-term mortality but does not increase the risk of postoperative dialysis dependence during the follow-up period.\u003c/p\u003e\n\u003cp\u003eTAAD frequently involves aortic branch vessels. Previous studies have highlighted that aortic branch involvement is a serious condition with significant potential for lethal end-organ malperfusion, which adversely affects clinical outcomes in patients with TAAD\u003csup\u003e1,9\u003c/sup\u003e. More extensive and severe branch vessel compromise is associated with worse clinical outcomes. Therefore, identifying a reliable indicator to evaluate the severity and extent of TAAD is crucial. Our study suggests that renal involvement has the potential to serve as a reliable indicator in this regard.\u003c/p\u003e\n\u003cp\u003eAssessing the severity and extent of TAAD is challenging due to the complex morphology of the dissected aorta, and current indicators are inadequate. Existing classifications, such as the 301 and Fuwai classifications, are complex and difficult to apply, with limited validation\u003csup\u003e10,11\u003c/sup\u003e. We found that the aortic branches were more severely compromised in the RAI group, accompanied by greater end-organ malperfusion. This is attributed to the mechanisms of TAAD development, where high-velocity blood enters the intimal tear, creating a false lumen that expands under the impact of antegrade blood flow. Branch vessels divert and reduce the flow impact. When the false lumen expands and reaches the thoracoabdominal aorta at the level of the renal artery, it indicates a stronger blood flow impact\u003csup\u003e12\u003c/sup\u003e, signalling a greater extent of the intimal tear and more severe branch vessel compromise, which aligns with the CTA findings. Therefore, we conclude that the extent and severity of TAAD is greater when the renal artery is involved. Furthermore, as the operative outcomes indicated, the proportion of patients requiring combined branch procedures was higher in the RAI group, primarily due to more severe corresponding branch vessel compromise. Additionally, longer operation times resulted from combined branch procedures in the RAI group also reflect the higher severity of branch involvement. Overall, renal involvement is a straightforward and effective indicator for assessing the severity and extent of aortic branch compromise in TAAD.\u003c/p\u003e\n\u003cp\u003eOur study reveals that TAAD patients with renal involvement had worse short-term surgical outcomes compared to those without renal involvement. This is primarily due to the fact that renal involvement indicates broader aortic branch involvement, often leading to increased end-organ malperfusion and complications, while also necessitating additional surgical interventions, thereby impacting surgical prognosis\u003csup\u003e13,14\u003c/sup\u003e. However, renal involvement does not equate to long-term renal injury. Postoperative dialysis dependence rates did not differ significantly. First, bilateral renal artery involvement is infrequent, and the compensatory function of the kidneys often mitigates the need for long-term dialysis.\u0026nbsp;Second, acute kidney injury is often reversible; postoperative dialysis is usually caused by acute renal injury resulting from systemic factors such as pre-renal hypoperfusion, hypothermia, nephrotoxic drugs, or visceral ischemia. As a result, dialysis requirements usually decrease over time, as renal injury can often be detected early and intervened in promptly. Overall, renal artery involvement does not significantly increase the likelihood of lifelong dialysis dependence.\u003c/p\u003e\n\u003cp\u003eWe did not use SCr, or renal malperfusion as indicators, as elevated SCr levels are common in TAAD and can result from various factors, such as metabolic acidosis, adverse effects of hypothermic circulatory arrest, or hypotension caused by cardiac tamponade, which could not accurately reflect the extent of TAAD compromise branches vessel. Additionally, previous research has noted that “differential enhancement of the kidney as seen on the CTA is predictive, but not prescriptive for renal malperfusion”\u003csup\u003e15\u003c/sup\u003e limiting the value of renal malperfusion as indicators for the extent of TAAD compromise.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur study has some limitations, TAAD patients with more severe and extensive conditions may face a higher risk of death before surgery can be performed, potentially introducing Berkson’s bias in our cohort. Nevertheless, the study provides significant clinical value, offering a reliable indicator for identifying the extent and severity of TAAD.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eRenal artery involvement in TAAD is a reliable indicator of more extensive and severe aortic branch compromise, strongly associated with end-organ malperfusion. Patients with renal involvement experience worse short-term surgical outcomes due to broader aortic branch vessel compromise. However, renal involvement does not increase the likelihood of postoperative dialysis dependence. Early detection of renal involvement may be beneficial for enabling timely intervention for compromised branch arteries, thereby mitigating the risks of malperfusion and improving surgical outcomes in TAAD patients.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eTAAD=type A aortic dissection\u003c/p\u003e\n\u003cp\u003eCTA=computer tomograph angiography\u003c/p\u003e\n\u003cp\u003eSAEs=Serious adverse events\u003c/p\u003e\n\u003cp\u003eSCr=Serum creatinine\u003c/p\u003e\n\u003cp\u003eBUN=Blood urea nitrogen\u003c/p\u003e\n\u003cp\u003ePSM=Propensity score matching\u003c/p\u003e\n\u003cp\u003eCPB=cardiopulmonary bypass\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclosures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData sharing was applicable from the first authors. The anonymous raw data that support the findings of this study are available from the first authors upon reasonable request and with permission of Fuwai hospital but restrictions apply to the availability of these data, which were used under license for the current study, and so are not publicly available. The full R script for data wrangling and data analysis could be shared per reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eLong Deng, Dong Zhao et.al (Surgeons) served as excellent consultants for this article. To all colleagues we express our sincerely grateful and best wishes.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eYang B, Patel HJ, Williams DM, Dasika NL, Deeb GM. Management of type A dissection with malperfusion. Ann Cardiothorac Surg. 2016;5(4):265-274.\u003c/li\u003e\n \u003cli\u003eNorton EL, Khaja MS, Williams DM, Yang B. 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The 301 Classification: A Proposed Modification to the Stanford Type B Aortic Dissection Classification for Thoracic Endovascular Aortic Repair Prognostication. Mayo Clin Proc. 2020;95(7):1329-1341.\u003c/li\u003e\n \u003cli\u003eQiu J, Luo X, Wu J, et al. A New Aortic Arch Dissection Classification: The Fuwai Classification. Front Cardiovasc Med. 2021;8:710281. Published 2021 Sep 14.\u003c/li\u003e\n \u003cli\u003eMikich B. Dissection of the aorta: a new approach [published correction appears in Heart. 2003 Mar;89(3):328. Mikich M [corrected to Mikich B]]. Heart. 2003;89(1):6-8.\u003c/li\u003e\n \u003cli\u003eMatalanis G, Ip S. Total aortic repair for acute type A aortic dissection: a new paradigm. J Vis Surg. 2018;4:79. Published 2018 Apr 26.\u003c/li\u003e\n \u003cli\u003eYang B, Rosati CM, Norton EL, et al. Endovascular Fenestration/Stenting First Followed by Delayed Open Aortic Repair for Acute Type A Aortic Dissection With Malperfusion Syndrome. Circulation. 2018;138(19):2091-2103.\u003c/li\u003e\n \u003cli\u003evan Bakel PAJ, Henry M, Kim KM, et al. Imaging features of renal malperfusion in aortic dissection. Eur J Cardiothorac Surg. 2022;61(4):805-813.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 4 are available in the Supplementary Files section\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Fuwai hospital","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Renal artery involvement, Type A aortic dissection, Compromised aortic branch vessels","lastPublishedDoi":"10.21203/rs.3.rs-5730684/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5730684/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Reliable indicators to assess the severity and extent of type A aortic dissection (TAAD) remain lacking. This study aimed to evaluate the role of renal artery involvement in this context.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e From January 2020 to June 2022, a total of 471 patients with TAAD who underwent open surgical repair were retrospectively analyzed. Based on computed tomography angiography, patients were categorized into two groups: those with renal involvement (RAI, n=289) and those without (non-RAI, n=182). To further validate the results, propensity score matching (PSM) was performed to minimize bias. A multivariate ordered logistic regression model was used to evaluate the association between renal involvement and the number of end-organ malperfusion. The incidence of dialysis dependence was calculated using the Kaplan-Meier method. Cox regression models were utilized to determine factors of overall and mid-term mortality.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The RAI group exhibited more extensive aortic branch involvement (all P\u0026lt;0.05) and required more concomitant branch procedures, with a higher incidence of end-organ malperfusion (P=0.006), as well as increased serious adverse events (P=0.009), which remain consistent after PSM matching. The multivariate ordered logistic regression model indicated that renal involvement was associated with malperfusion [Odds ratio=2.00, 95% confidence interval (CI):1.25-3.27]. Multivariable Cox regression analysis identified renal involvement as an independent risk factor for overall mortality [hazard ratio (HR)=3.48, 95%CI:1.15-10.47, P=0.027] and mid-term mortality (HR=3.42, 95%CI:1.14-10.31, P=0.029). Kaplan-Meier analysis revealed no significant difference in dialysis dependence.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eRenal artery involvement signifies more severe aortic branch compromise and malperfusion, and worse prognosis.\u003c/p\u003e","manuscriptTitle":"Renal Artery Involvement as a Reliable Indicator of Severe Branch Vessel Involvement and Malperfusion in Type A Aortic Dissection","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-01 09:14:52","doi":"10.21203/rs.3.rs-5730684/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"74b0f066-9b7b-4141-9250-7c40fce71039","owner":[],"postedDate":"January 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-01-01T09:14:52+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-01 09:14:52","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5730684","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5730684","identity":"rs-5730684","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}