Outcomes after tetralogy of Fallot repair with preservation of intact pulmonary valve structure

Outcomes after tetralogy of Fallot repair with preservation of intact pulmonary valve structure | 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 Outcomes after tetralogy of Fallot repair with preservation of intact pulmonary valve structure Seung Woo Ryu, Dong Hee Jang, Su Jin Kwon, Dong-Hee Kim, Eun Seok Choi, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8868645/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract The optimal post-repair pulmonary valve annulus (PVA) diameter in tetralogy of Fallot (TOF) may be far smaller than anticipated. Therefore, selected patients can undergo repair without manipulating the PV structure. Of the 347 patients who underwent TOF repair with PVA preservation (AP) from January 2016 to December 2023, 100 had AP while leaving the PV structure untouched. Median age, weight, and PVA (Z) at repair were 125 days (interquartile range [IQR], 96.5–167.5), 6.3 kg (IQR, 5.1–7.1), and −0.8 (IQR, −1.8 to 0.3), respectively. One non-cardiac late death occurred 9 months after repair. During a median 46.2 months follow-up, 14 patients (14%) required reinterventions for significant right ventricular outflow tract obstruction (RVOTO): balloon pulmonary valvuloplasty (BPV) in 6, surgical RVOTO relief in 4, and BPV followed by surgery in 4 (including 1 who received a right ventricle to pulmonary artery conduit to bypass a left anterior descending coronary artery crossing the RVOT). Except for the conduit recipient, only 2 patients showed significant RVOTO (n = 1) and significant pulmonary regurgitation (PR) (n = 1) at the last follow-up. On Cox regression, neonatal repair (hazard ratio [HR], 5.12, P = 0.02) and a higher P RV/LV (post-repair pressure ratio of the right ventricle to the left ventricle) (HR 1.61 per 0.1 increase, P = 0.04) were risk factors for decreased time to reintervention. The post-repair P RV/LV cutoff predicting reintervention was 0.52. Preserving an intact PV during TOF repair is feasible in a subset. Post-repair RVOTO, when it occurs, can be relieved by a timely reintervention without inducing significant PR. Tetralogy of Fallot Pulmonary valve annulus Annulus preservation Outcomes Right ventricular outflow tract obstruction Figures Figure 1 Figure 2 Figure 3 Figure 4 INTRODUCTION Optimal management of tetralogy of Fallot (TOF) entails precise surgical algorithm. Because both excessive post-repair pulmonary stenosis (PS) and pulmonary regurgitation (PR) can lead to significant right ventricular (RV) dysfunction from long-term exposure to pressure and volume overloads, balancing PS and PR (i.e. incurring the minimal sum of PS and PR) may be crucial, particularly when the pulmonary valve annulus (PVA) is marginally small [1–3]. In ToF repair with PVA preservation, surgical manipulation on the pulmonary valve (PV) is generally inevitable to alleviate postoperative RV outflow tract obstruction (RVOTO). However, excessive PV intervention for patients with a relatively sizable PVA can induce superfluous PR [3–5]. We previously reported that, when TOF is repaired employing aggressive PVA preservation strategy, the smallest acceptable PVA diameter can be substantially smaller than the patient’s normal annulus size [5]. Accordingly, a subset of patients with a relatively sizable PVA and PV orifice may forgo any surgical manipulation on the PVA and leaflets, preserving the structural integrity of the PV. This ‘intentionally biased strategy in favor of PVA-preservation’ aims to avoid any unnecessary PR at the expense of an ‘acceptable’ degree of pulmonary stenosis (PS). Potential trade-offs of this apparently ‘overly aggressive’ strategy include subsequent RVOTO and the need for RVOT reintervention. We aimed to (1) characterize the outcomes when the PV structure was left untouched at repair−specifically focusing on residual RVOTO, PR, and the need for reintervention− and (2) identify the risk factors for these adverse events. PATIENTS AND METHODS The Institutional Review Board of Asan Medical Center approved the study (2025 − 0210) and waived the need for informed consent owing to its retrospective design. Between January 2016 and December 2023, 376 consecutive patients underwent TOF repair at our institution, and PVA preservation (AP) was achieved in 347 patients (347/378, 91.8%). Of these 347 patients, 100 patients (100/347, 28.8%) underwent AP without any surgical intervention on the PV leaflets and commissures. Median age and body weight at repair were 125 days (interquartile range [IQR], 96.5–167.5) and 6.3 kg (IQR, 5.1–7.1), respectively. Sixty patients (60%) were male; 10 underwent neonatal repairs. Three patients underwent pre-repair palliation: a central shunt for a symptomatic neonate to promote growth of a small PVA [6] and branch pulmonary arteries (PAs) (n = 1); a left modified Blalock−Taussig shunt to establish blood flow to an interrupted left PA without a ductus (n = 1), and a ductal stent for a disconnected left pulmonary artery with ductus-dependent flow (n = 1). Urgent operation was performed due to increasing episodes of desaturation in 19 patients, and 39 patients had long narrow infundibulum necessitating pre-repair oral propranolol administration to prevent hypoxic spell. Pre-repair echocardiography showed a median PVA diameter of 8.4 mm (IQR, 6.8−9.7) and a PVA z-score of −0.8 (IQR, −1.8 to 0.3) (Table 1 ) [7]. The primary outcomes were the need for catheter-based or surgical reintervention for significant RVOTO (RVOT flow velocity ≥ 3.5 m/s) and significant PR (grade ≥ III/IV). Table 1 Patient characteristics Variables n (%) or median (IQR) Preoperative variables Male sex 60 (60%) Age at repair, days 125 (96.5–167.5) Birth weight, kg 3.1 (2.7–3.4) Low birth weight (< 2.5 kg) 20 (20%) Gestational age (weeks) 39 (38.0–39.4) Prematurity (gestational age < 37 weeks) 13 (13%) Body weight at repair (kg) 6.3 (5.1–7.1) Pre-repair PVA (Z) -0.81 (-1.78–-0.29) Operative variables Pre-repair palliative surgery 2 (2%) RVOT patch augmentation 71 (71%) Isolated infundibular patch 37 (37%) Infundibular plus MPA patch 29 (29%) Isolated MPA patch 5 (5%) Intraoperatively measured PVA converted to z-score −1.64 (−2.21 to −0.86) P RV/LV 0.42 (0.35–0.49) CPB time, min 90.5 (81.5–105.0) ACC time, min 59.5 (47.0–68.8) ACC, aortic cross-clamp; CPB, cardiopulmonary bypass; IQR, interquartile range; MPA, main pulmonary artery; P RV/LV , pressure ratio of the right ventricle to the left ventricle; PVA (Z), z-score of the pulmonary valve annulus diameter; RVOT, right ventricular outflow tract. Surgical techniques TOF repair was performed under cardiopulmonary bypass with moderate hypothermia (28°C) and intermittent cold blood cardioplegia delivered via the aortic root. Through an oblique right atriotomy or a vertical right ventriculotomy, the parietal extension of the infundibular septum was extensively resected until the PV was clearly visualized from the RV inlet or through the right ventriculotomy. Surgical strategy to maintain the intact PV structure is determined in the operating theater. After patch closure of the ventricular septal defect, a Hegar dilator was introduced through the PV to measure the PVA diameter. If the measured PV orifice diameter exceeded the normal PVA dimension (based on echocardiographic nomograms) minus 4 mm, we chose to preserve the intact PV structure [5]. If the PV orifice diameter was between the normal PVA dimension minus 5 mm and 4 mm, the main PA was incised longitudinally to assess PV morphology. If the valve leaflets appeared thin and functional, the PV was left untouched to preserve valve integrity. However, if the leaflets looked thickened and dysfunctional, strategy of preserving the intact PV was abandoned and appropriate surgical intervention was performed on the commissures and leaflets. Following weaning from cardiopulmonary bypass, the pressure ratio of the right ventricle to the left ventricle (P RV/LV) and the pressure gradient between the RV and the main PA were measured directly using a pressure needle. If the P RV/LV exceeded 0.8 with a notable trans-RVOT gradient, cardiopulmonary bypass was reinstituted. If high RV pressure was attributed to the subvalvar obstruction and a right ventriculotomy had not been performed at repair, a limited (< 10 mm) infundibular incision was made to permit additional muscle resection and RVOT patch augmentation using a double-layered polytetrafluoroethylene patch (Gore Acuseal cardiovascular patch, Gore-Tex, CA, USA). If a right ventriculotomy had been performed for RVOTO relief, the strategy of ‘leaving the PV structure untouched’ was abandoned and extensive PV commissurotomy was performed. The main PA arteriotomy made for PV exploration was closed with an elliptical Acuseal patch in the same manner. Statistical analysis Categorical variables are presented as counts with percentages, and continuous variables are presented as medians with interquartile ranges (IQRs) owing to non-normal distribution. Normality was assessed using the Shapiro−Wilk test. Freedom from time-related adverse events was estimated with the Kaplan-Meier method. A Cox proportional hazards model was fit to identify univariable and multivariable risk factors for decreased time to reintervention for RVOTO after repair. A cutoff predicting RVOTO reintervention was derived using area under the receiver operating characteristic curve analysis. Patients were dichotomized by cutoff for Kaplan–Meier analysis with log-rank testing. A P -value ≤ 0.05 was considered statistically significant. All statistical analyses were performed with R software version 4.4.1 (R Foundation for Statistical Computing, Vienna, Austria). RESULTS The PV morphology was bicuspid in 77 patients and tricuspid in 23 patients. For RVOT reconstruction above or below the PV, 71 patients required subvalvar or supravalvar patch augmentation: isolated infundibular patching in 37, isolated supravalvar patching in 5, and combined infundibular plus supravalvar patching in 29. Median intraoperative PVA diameter, measured with a Hegar dilator and converted to a PVA (Z), was −1.64 (IQR, −2.21 to −0.86), which was consistently smaller than PVA (Z) measured by pre-repair echocardiography. Median immediate post-bypass P RV/LV measured directly with a pressure needle was 0.42 (IQR, 0.35–0.49) (Table 1 ). On immediate postoperative echocardiography, median RVOT velocity was 2.4 m/s (IQR, 1.9−2.7 m/s). Median follow-up duration after repair was 46.2 months (IQR, 23.5–73.5 months). There was one late death in a girl born prematurely (birth weight of 1.79 kg) with multiple genetic problems, including Edwards syndrome, VACTERL (vertebral anomalies, anal atresia, cardiac defects, tracheoesophageal fistula with esophageal atresia, renal anomalies, and limb anomalies) association, bronchomalacia, and a congenital left diaphragmatic hernia requiring surgical repair. TOF was repaired at post-natal 3.5 months (body weight at repair: 3.8 kg) with preservation of PV integrity. Intraoperative measurement of P RV/LV was 0.41.Postoperative echocardiography at post-repair 6 months showed RVOT flow velocity of 3.0 m/s with acceptable biventricular function and no PR. Despite excellent postoperative cardiac status, she developed progressive chronic lung disease and died at 7 months after repair. Fourteen patients (14%) required reintervention for significant RVOTO during follow-up, including balloon pulmonary valvuloplasty (BPV, n = 6), surgical reintervention (n = 4), and BPV followed by surgery (n = 4) (Fig. 1 ; Table 2 ). Of the eight patients who required surgical reintervention, seven underwent infundibular muscle resection without transannular patch placement. One patient required implantation of an RV−PA conduit to avoid violation of an anomalous left anterior descending coronary artery crossing the RVOT. Excluding the late death and the RV−PA conduit recipient, significant residual RVOTO (RVOT flow velocity ≥ 3.5 m/s) was observed in only one patient (1/98, 1%) on last follow-up echocardiography at median 37.4 months (IQR, 17.0−64.0 months) after repair. Significant PR (≥ grade III/IV) likewise occurred in one patient (1/98, 1%). Freedom from reintervention for RVOTO was 92.7% at 1 year and 85.0% at 5 years (Fig. 2 a). Freedom from significant PR remained 100% at 1 and 5 years and 92.9% at 7 years (Fig. 2 b). On Cox regression, neonatal repair (hazard ratio [HR]: 5.12, 95% confidence interval, CI: 1.32−19.77, P = 0.02) and a higher immediate post-repair P RV/LV (HR 1.61 per 0.1 increase, CI: 1.03−2.50, P = 0.04) were associated with decreased time to RVOT reintervention (Table 3 ). Receiver operating characteristic curve analysis identified 0.52 as the P RV/LV cutoff predicting RVOT reintervention (area under the curve, 0.739; sensitivity, 57.1%; specificity, 87.8%) (Fig. 3 ). Patients with P RV/LV ≤ 0.52 (n = 82, P < 0.001) and those with non-neonatal repair (n = 90, P 0.52 (n = 18) and neonatal repair (n = 10) (Fig. 4 a and 4 b). Table 2 Characteristics of patients with RVOT reintervention No Age at repair (days) Previous shunt Preoperative echocardiography MPA patching Infundibular patching Intraoperative measurement P RV/LV Pre-reintervention echocardiography Reintervention Echocardiography at last follow-up PVA (mm) PVA (Z) PVA (mm) PVA (Z) RVOT flow velocity (m/s) PR BPV Reoperation RVOT flow velocity (m/s) PR #1 175 No 10.3 0.04 Yes Yes 7.0 −2.62 0.45 4.6 None Yes 3.2 trivial #2 182 No 8.8 −0.43 Yes Yes 7.0 −2.45 0.53 4.5 None Yes Yes 2.6 III/IV #3 262 Yes 11.0 0.06 Yes Yes 9.0 −1.29 0.37 4.2 None Yes 3.3 trivial #4 77 No 5.8 −3.06 Yes Yes 7.0 −1.75 0.38 3.5 None Yes 2.7 trivial #5 7 No 5.7 −1.89 Yes Yes 6.0 −1.61 0.65 5.2 None Yes Yes 2.9 I/IV (valved conduit)* #6 178 No 8.2 −0.90 No No 7.0 −2.21 0.53 3.8 None Yes 2.7 I/IV #7 115 No 10.2 0.54 No No 7.0 −1.87 0.57 4.1 None Yes 3.2 trivial #8 205 No 11.4 0.71 No No 10.0 −0.05 0.56 4.3 None Yes 2.4 trivial #9 7 No 5.0 −3.03 Yes Yes 4.0 −4.36 0.42 4.3 None Yes 3.1 II/IV #10 176 No 7.5 −1.13 No Yes 6.0 −2.56 0.44 4.4 None Yes 1.9 I/IV #11 14 No 6.5 −1.70 No Yes 5.0 −3.30 0.35 4.3 None Yes 3.7 trivial #12 16 No 4.3 −3.33 Yes Yes 4.0 −3.76 0.87 4.3 None Yes Yes 2.4 II/IV #13 6 No 6.7 −1.64 No Yes 6.0 −0.05 0.54 3.5 None Yes Yes 2.6 I/IV #14 72 No 7.4 −1.09 No Yes 7.0 −1.47 0.61 3.9 None Yes 3.0 trivial BPV, balloon pulmonary valvuloplasty; MPA, main pulmonary artery; PR, pulmonary regurgitation; P RV/LV , post-repair pressure ratio of the right ventricle and the left ventricles; PVA, pulmonary valve annulus diameter; PVA (Z), z-score of pulmonary valve annulus diameter; RVOT, right ventricular outflow tract. ∗ This patient underwent right ventricle to pulmonary artery conduit implantation to establish a dual RVOT pathway because the left anterior descending coronary artery was crossing the RVOT. Table 3 Cox regression analysis to identify risk factors for RVOT reintervention Variable Univariable Multivariable HR (95% CI) P -value HR (95% CI) P -value Sex (male) 2.51 (0.70-9.00) 0.16 Age at repair 0.99 (0.98-1.00) 0.10 Neonatal repair 8.42 (2.78–25.48) < 0.001 5.12 (1.32–19.77) 0.02 Body weight at repair 0.73 (0.52–1.04) 0.08 Preoperative PVA (Z) (0.1 increase) 0.98 (0.94–1.02) 0.24 Intraoperative PVA (Z) (0.1 increase) 0.94 (0.89-1.00) 0.06 P RV/LV (0.1 increase) 2.15 (1.42–3.27) < 0.001 1.61 (1.03–2.50) 0.04 MPA patching 1.79 (0.63–5.11) 0.28 Infundibular patching 2.25 (0.63–8.07) 0.21 CI, confidence interval; HR, hazard ratio; MPA, main pulmonary artery; P RV/LV , post-repair pressure ratio of the right ventricle to the left ventricle; PVA (Z), z-score of pulmonary valve annulus; RVOT, right ventricular outflow tract. DISCUSSION Surgical management of TOF has evolved with a growing emphasis on the PVA preservation to alleviate long-term complications such as PR, RV dilation, and ventricular arrhythmia [8.9]. Despite the theoretical advantages of PVA preservation, however, placement of a transannular patch remains common in practice, primarily due to concerns about residual RVOTO [10]. Although previous studies have underscored that PV-sparing or PVA preservation may offer several benefits [8,9,11,12], even minimal interventions on the PV, such as limited commissurotomy, can disrupt the structural integrity of the native valve and lead to progressive PR over time. Unlike conventional valve-sparing techniques that involve some degree of surgical manipulation on the leaflets and commissures, our strategy in patients with relatively sizable PV orifice was to leave the whole native PV structure (i.e. valve annulus, leaflets and commissures) entirely untouched. This approach may yield favorable long-term outcomesࣧbetter preservation of native valve function and prevention of progressive PRࣧultimately reducing the need for late PV implantation [13,14]. A central practical question for applying this seemingly too aggressive valve sparing strategy is, How small is too small? Whether to preserve the PVA at TOF repair remains debated, particularly regarding the optimal PVA (Z) threshold that guarantees effective PV function while minimizing postoperative RVOTO [5,11,15,16]. In this study, pre-repair PVA (Z) and the intraoperatively measured PVA diameter (or corresponding PVA z-score) did not predict later RVOT reintervention after repair. Instead, intraoperative hemodynamics—specifically, the post-repair P RV/LV —independently predicted PV reintervention. These findings align with prior reports on the utility of P RV/LV in intraoperative decision-making for RVOT reconstruction [5,17]. Because residual RVOTO is often driven by subvalvar muscle hypertrophy, complete resection of subvalvar aberrant muscle bundles at the initial repair is essential. Inadequate relief of subvalvar obstruction can lead to persistent RVOTO and additional interventions. Notably, none of eight patients who underwent surgical reintervention for RVOTO required conversion to a transannular patch, substantiating the importance of adequate subvalvar resection at the initial operation. Neonatal repair constituted 10% of the cohort but accounted for more than one-third of RVOT reinterventions. This finding accords with prior reports that neonatal repair confers a higher risk of recurrent RVOTO after primary repair [17,18]. This greater susceptibility of neonates may reflect unfavorable anatomical disposition prompting early repair and technical challenges inherent to small hearts. In this study, most of the reinterventions for RVOTO after neonatal repair were attributed to residual subvalvar obstruction rather than inadequate PVA growth. These observations underscore the need for meticulous relief of subvalvar obstruction at the initial repair in neonates, even when the PVA appears sizable. In this cohort, infundibular incisions were performed in approximately two-thirds of patients (66%). Although RV incisions have been implicated in ventricular dilation, dysfunction, and arrhythmias [2], RV remodeling appears to be driven more by the severity of PR rather than by the ventricular incision per se [5,9,11,19]. Infundibular patching is often necessary to achieve complete resection of aberrant subvalvar muscle bundles and a nonrestrictive subvalvar outflow tract. However, aneurysmal dilatation of the infundibulumࣧparticularly in the setting of residual RVOTOࣧremains a concern. To mitigate this risk, we limit the incision to the extent of the deviated conal septum and use stout and rigid patch materials, such as an Acuseal patch. Study limitations This study had limitations, including its retrospective, single-center design. The relatively short follow-up period limited assessment of long-term outcomes, particularly the risk of progressive RVOTO and PR over longer time frames. Additionally, the decision to preserve the PV structure intact was based on intraoperative surgical judgment, which may have introduced selection bias. Furthermore, the optimal timing and criteria for reintervention remain uncertain, and the detection of RVOTO or PR depends on the timing and frequency of echocardiographic follow-up. Conclusions A substantial subset of TOF patients can undergo repair with PVA preservation and no PV intervention. When significant residual RVOTO occurs, timely catheter-based or surgical reintervention can relieve obstruction without inducing significant PR. Because subvalvar muscle hypertrophy is the principal cause of post-repair RVOTO, complete subvalvar relief at the initial repair is essential when PV integrity is to be preserved intact. Declarations Acknowledgements: none Author contributions Conceptualization: [Tae-Jin Yun], [Seung Woo Ryu] [Eun Seok Choi], [Bo Sang Kwon]; Methodology: [Seung Woo Ryu], [Dong-Hee Kim] [Su Jin Kwon] [Chun Soo Park]; Formal analysis and investigation: [Seung Woo Ryu], [Dong-Hee Kim]: Writing-original draft preparation: [Seung Woo Ryu]; Writing-review and editing [Tae-Jin Yun], [Seung Woo Ryu]: Supervision: [Tae-Jin Yun]. Declaration of Funding and Competing interests None of the authors has a financial relationship with a commercial entity with an interest in the subject matter of this manuscript or other conflicts of interest to disclose, and no funding was received for this study. Disclosure statement: The authors report no financial relationships or other conflicts of interest. Funding statement : No funding was received for this study. References Frigiola A, Redington AN, Cullen S, Vogel M (2004) Pulmonary regurgitation is an important determinant of right ventricular contractile dysfunction in patients with surgically repaired tetralogy of Fallot. Circulation 110(11 Suppl 1):II153-7. https://doi.org/10.1161/01.CIR.0000138397.60956.c2. Gatzoulis MA, Balaji S, Webber SA et al (2000) Risk factors for arrhythmia and sudden cardiac death late after repair of tetralogy of Fallot: a multicentre study. Lancet 356(9234):975–981. https://doi.org/10.1016/S0140-6736(00)02714-8. 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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-8868645","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":592666412,"identity":"22627d10-aa01-4cb1-80a1-1cae2199310c","order_by":0,"name":"Seung Woo Ryu","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Seung","middleName":"Woo","lastName":"Ryu","suffix":""},{"id":592666417,"identity":"deada42f-0707-4983-a3d8-10ba18b18f15","order_by":1,"name":"Dong Hee Jang","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Dong","middleName":"Hee","lastName":"Jang","suffix":""},{"id":592666418,"identity":"51fbca0c-4e09-42b9-9c35-16495df94108","order_by":2,"name":"Su Jin Kwon","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Su","middleName":"Jin","lastName":"Kwon","suffix":""},{"id":592666419,"identity":"1206c75a-1633-4875-99d2-7d9a51a96a33","order_by":3,"name":"Dong-Hee Kim","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Dong-Hee","middleName":"","lastName":"Kim","suffix":""},{"id":592666426,"identity":"0f8f0254-1841-4848-ad93-93df4314697c","order_by":4,"name":"Eun Seok Choi","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Eun","middleName":"Seok","lastName":"Choi","suffix":""},{"id":592666428,"identity":"35606f19-8c04-4d07-87fe-b494cf1ff525","order_by":5,"name":"Bo Sang Kwon","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Bo","middleName":"Sang","lastName":"Kwon","suffix":""},{"id":592666430,"identity":"d9fe7409-c05c-475e-a473-f0e4d7b40124","order_by":6,"name":"Chun Soo Park","email":"","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":false,"prefix":"","firstName":"Chun","middleName":"Soo","lastName":"Park","suffix":""},{"id":592666431,"identity":"4b22b25f-4494-4db5-b05c-de2fa1ea7974","order_by":7,"name":"Tae-Jin Yun","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxUlEQVRIiWNgGAWjYFCCA0BcAedZMEgQ0sAD1nIGzpcgRgsQMLaRosWe8YyZdOE8u2j+BvaHDz62STBIzj5AyBaglpnbknNnHOAxNpwJ1CLNl0CEFt5tzLkbGHjYpHmBWuR4CPoFpGVOPVAL+/PfJGhpOAzUwmDGDNIiTVDLgWPF1jzHjufOOMxjLDnjnASPZA8BLewzDm+8zVNTndvf3v7ww4cyGzmJMwS0MEicMIAwmGEuJQj42x8QVjQKRsEoGAUjGwAAPTY3Sy/YvuQAAAAASUVORK5CYII=","orcid":"","institution":"Asan Medical Center, University of Ulsan","correspondingAuthor":true,"prefix":"","firstName":"Tae-Jin","middleName":"","lastName":"Yun","suffix":""}],"badges":[],"createdAt":"2026-02-13 07:24:45","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8868645/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8868645/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103167351,"identity":"9c415ed0-fa7e-4eee-a35f-989b05ca9515","added_by":"auto","created_at":"2026-02-22 12:47:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":63760,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of outcomes following TOF repair without PV intervention.\u003c/p\u003e\n\u003cp\u003eBPV, balloon pulmonary valvuloplasty; PR, pulmonary regurgitation; PV, pulmonary valve; RVOTO, right ventricular outflow tract obstruction.\u003c/p\u003e","description":"","filename":"Fig1.png","url":"https://assets-eu.researchsquare.com/files/rs-8868645/v1/a3eaf0d7c05bec4f49137b2e.png"},{"id":103504910,"identity":"da5aacbc-20c3-430d-b697-92191b007904","added_by":"auto","created_at":"2026-02-26 13:22:03","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":120243,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan-Meier curves showing freedom from reintervention for RVOTO (a) and freedom from significant PR (b) following TOF repair without PV intervention. Shaded areas denote 95% confidence intervals.\u003c/p\u003e\n\u003cp\u003ePR, pulmonary regurgitation; RVOTO, right ventricular outflow tract obstruction.\u003c/p\u003e","description":"","filename":"Fig2.png","url":"https://assets-eu.researchsquare.com/files/rs-8868645/v1/1921a8b5a893e767469952e6.png"},{"id":103504991,"identity":"439b1946-a65a-4f9b-92be-d5f872b41070","added_by":"auto","created_at":"2026-02-26 13:22:21","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":51532,"visible":true,"origin":"","legend":"\u003cp\u003eReceiver operating characteristic curve for predicting RVOT reintervention using the P\u003csub\u003eRV/LV \u003c/sub\u003eas the predictor. The optimal cut-off value was 0.52, with an area under the curve of 0.739. Sensitivity and specificity were 57.1% and 87.8%, respectively.\u003c/p\u003e\n\u003cp\u003eP\u003csub\u003eRV/LV\u003c/sub\u003e, pressure ratio of the right ventricle to the left ventricle; PV, pulmonary valve; RVOT, right ventricular outflow tract.\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-8868645/v1/be3c46b786ebf3d28678de7a.png"},{"id":103167352,"identity":"de9a62e6-a818-4f56-b98e-790b64029a89","added_by":"auto","created_at":"2026-02-22 12:47:02","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":130139,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan-Meier curve for freedom from RVOT reintervention stratified by P\u003csub\u003eRV/LV \u003c/sub\u003e(A) and neonatal vs. non-neonatal repair (B). Shaded areas denote 95% confidence intervals.\u003c/p\u003e\n\u003cp\u003eP\u003csub\u003eRV/LV\u003c/sub\u003e, pressure ratio of the right ventricle to the left ventricle; RVOT, right ventricular outflow tract.\u003c/p\u003e","description":"","filename":"Fig4.png","url":"https://assets-eu.researchsquare.com/files/rs-8868645/v1/e53ceab1838d3b91d00f8a04.png"},{"id":103509259,"identity":"3032adca-ce3c-46df-a92e-17c06ba00c9e","added_by":"auto","created_at":"2026-02-26 13:57:44","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1131280,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8868645/v1/20f360f0-0d7d-4280-90fd-824848eabc34.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Outcomes after tetralogy of Fallot repair with preservation of intact pulmonary valve structure","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eOptimal management of tetralogy of Fallot (TOF) entails precise surgical algorithm. Because both excessive post-repair pulmonary stenosis (PS) and pulmonary regurgitation (PR) can lead to significant right ventricular (RV) dysfunction from long-term exposure to pressure and volume overloads, balancing PS and PR (i.e. incurring the minimal sum of PS and PR) may be crucial, particularly when the pulmonary valve annulus (PVA) is marginally small [1\u0026ndash;3]. In ToF repair with PVA preservation, surgical manipulation on the pulmonary valve (PV) is generally inevitable to alleviate postoperative RV outflow tract obstruction (RVOTO). However, excessive PV intervention for patients with a relatively sizable PVA can induce superfluous PR [3\u0026ndash;5].\u003c/p\u003e \u003cp\u003eWe previously reported that, when TOF is repaired employing aggressive PVA preservation strategy, the smallest acceptable PVA diameter can be substantially smaller than the patient\u0026rsquo;s normal annulus size [5]. Accordingly, a subset of patients with a relatively sizable PVA and PV orifice may forgo any surgical manipulation on the PVA and leaflets, preserving the structural integrity of the PV. This \u0026lsquo;intentionally biased strategy in favor of PVA-preservation\u0026rsquo; aims to avoid any unnecessary PR at the expense of an \u0026lsquo;acceptable\u0026rsquo; degree of pulmonary stenosis (PS). Potential trade-offs of this apparently \u0026lsquo;overly aggressive\u0026rsquo; strategy include subsequent RVOTO and the need for RVOT reintervention. We aimed to (1) characterize the outcomes when the PV structure was left untouched at repair\u0026minus;specifically focusing on residual RVOTO, PR, and the need for reintervention\u0026minus; and (2) identify the risk factors for these adverse events.\u003c/p\u003e"},{"header":"PATIENTS AND METHODS","content":"\u003cp\u003e The Institutional Review Board of Asan Medical Center approved the study (2025\u0026thinsp;\u0026minus;\u0026thinsp;0210) and waived the need for informed consent owing to its retrospective design. Between January 2016 and December 2023, 376 consecutive patients underwent TOF repair at our institution, and PVA preservation (AP) was achieved in 347 patients (347/378, 91.8%). Of these 347 patients, 100 patients (100/347, 28.8%) underwent AP without any surgical intervention on the PV leaflets and commissures. Median age and body weight at repair were 125 days (interquartile range [IQR], 96.5\u0026ndash;167.5) and 6.3 kg (IQR, 5.1\u0026ndash;7.1), respectively. Sixty patients (60%) were male; 10 underwent neonatal repairs. Three patients underwent pre-repair palliation: a central shunt for a symptomatic neonate to promote growth of a small PVA [6] and branch pulmonary arteries (PAs) (n\u0026thinsp;=\u0026thinsp;1); a left modified Blalock\u0026minus;Taussig shunt to establish blood flow to an interrupted left PA without a ductus (n\u0026thinsp;=\u0026thinsp;1), and a ductal stent for a disconnected left pulmonary artery with ductus-dependent flow (n\u0026thinsp;=\u0026thinsp;1). Urgent operation was performed due to increasing episodes of desaturation in 19 patients, and 39 patients had long narrow infundibulum necessitating pre-repair oral propranolol administration to prevent hypoxic spell. Pre-repair echocardiography showed a median PVA diameter of 8.4 mm (IQR, 6.8\u0026minus;9.7) and a PVA z-score of \u0026minus;0.8 (IQR, \u0026minus;1.8 to 0.3) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) [7]. The primary outcomes were the need for catheter-based or surgical reintervention for significant RVOTO (RVOT flow velocity\u0026thinsp;\u0026ge;\u0026thinsp;3.5 m/s) and significant PR (grade \u0026ge; III/IV).\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 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\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003en (%) or median (IQR)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative variables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale sex\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e60 (60%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge at repair, days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e125 (96.5\u0026ndash;167.5)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBirth weight, kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.1 (2.7\u0026ndash;3.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLow birth weight (\u0026lt;\u0026thinsp;2.5 kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (20%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGestational age (weeks)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39 (38.0\u0026ndash;39.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrematurity (gestational age\u0026thinsp;\u0026lt;\u0026thinsp;37 weeks)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 (13%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody weight at repair (kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.3 (5.1\u0026ndash;7.1)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePre-repair PVA (Z)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.81 (-1.78\u0026ndash;-0.29)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eOperative variables\u003c/b\u003e\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\u003ePre-repair palliative surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (2%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRVOT patch augmentation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e71 (71%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIsolated infundibular patch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37 (37%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInfundibular plus MPA patch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29 (29%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIsolated MPA patch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (5%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIntraoperatively measured PVA converted to z-score\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026minus;1.64 (\u0026minus;2.21 to \u0026minus;0.86)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP\u003csub\u003eRV/LV\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.42 (0.35\u0026ndash;0.49)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCPB time, min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e90.5 (81.5\u0026ndash;105.0)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eACC time, min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59.5 (47.0\u0026ndash;68.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eACC, aortic cross-clamp; CPB, cardiopulmonary bypass; IQR, interquartile range; MPA, main pulmonary artery; P\u003csub\u003eRV/LV\u003c/sub\u003e, pressure ratio of the right ventricle to the left ventricle; PVA (Z), z-score of the pulmonary valve annulus diameter; RVOT, right ventricular outflow tract.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSurgical techniques\u003c/h2\u003e \u003cp\u003eTOF repair was performed under cardiopulmonary bypass with moderate hypothermia (28\u0026deg;C) and intermittent cold blood cardioplegia delivered via the aortic root. Through an oblique right atriotomy or a vertical right ventriculotomy, the parietal extension of the infundibular septum was extensively resected until the PV was clearly visualized from the RV inlet or through the right ventriculotomy. Surgical strategy to maintain the intact PV structure is determined in the operating theater. After patch closure of the ventricular septal defect, a Hegar dilator was introduced through the PV to measure the PVA diameter. If the measured PV orifice diameter exceeded the normal PVA dimension (based on echocardiographic nomograms) minus 4 mm, we chose to preserve the intact PV structure [5]. If the PV orifice diameter was between the normal PVA dimension minus 5 mm and 4 mm, the main PA was incised longitudinally to assess PV morphology. If the valve leaflets appeared thin and functional, the PV was left untouched to preserve valve integrity. However, if the leaflets looked thickened and dysfunctional, strategy of preserving the intact PV was abandoned and appropriate surgical intervention was performed on the commissures and leaflets. Following weaning from cardiopulmonary bypass, the pressure ratio of the right ventricle to the left ventricle (P\u003csub\u003eRV/LV)\u003c/sub\u003e and the pressure gradient between the RV and the main PA were measured directly using a pressure needle. If the P\u003csub\u003eRV/LV\u003c/sub\u003e exceeded 0.8 with a notable trans-RVOT gradient, cardiopulmonary bypass was reinstituted. If high RV pressure was attributed to the subvalvar obstruction and a right ventriculotomy had not been performed at repair, a limited (\u0026lt;\u0026thinsp;10 mm) infundibular incision was made to permit additional muscle resection and RVOT patch augmentation using a double-layered polytetrafluoroethylene patch (Gore Acuseal cardiovascular patch, Gore-Tex, CA, USA). If a right ventriculotomy had been performed for RVOTO relief, the strategy of \u0026lsquo;leaving the PV structure untouched\u0026rsquo; was abandoned and extensive PV commissurotomy was performed. The main PA arteriotomy made for PV exploration was closed with an elliptical Acuseal patch in the same manner.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eCategorical variables are presented as counts with percentages, and continuous variables are presented as medians with interquartile ranges (IQRs) owing to non-normal distribution. Normality was assessed using the Shapiro\u0026minus;Wilk test. Freedom from time-related adverse events was estimated with the Kaplan-Meier method. A Cox proportional hazards model was fit to identify univariable and multivariable risk factors for decreased time to reintervention for RVOTO after repair. A cutoff predicting RVOTO reintervention was derived using area under the receiver operating characteristic curve analysis. Patients were dichotomized by cutoff for Kaplan\u0026ndash;Meier analysis with log-rank testing. A \u003cem\u003eP\u003c/em\u003e-value \u0026le; 0.05 was considered statistically significant. All statistical analyses were performed with R software version 4.4.1 (R Foundation for Statistical Computing, Vienna, Austria).\u003c/p\u003e \u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThe PV morphology was bicuspid in 77 patients and tricuspid in 23 patients. For RVOT reconstruction above or below the PV, 71 patients required subvalvar or supravalvar patch augmentation: isolated infundibular patching in 37, isolated supravalvar patching in 5, and combined infundibular plus supravalvar patching in 29. Median intraoperative PVA diameter, measured with a Hegar dilator and converted to a PVA (Z), was \u0026minus;1.64 (IQR, \u0026minus;2.21 to \u0026minus;0.86), which was consistently smaller than PVA (Z) measured by pre-repair echocardiography. Median immediate post-bypass P\u003csub\u003eRV/LV\u003c/sub\u003e measured directly with a pressure needle was 0.42 (IQR, 0.35\u0026ndash;0.49) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). On immediate postoperative echocardiography, median RVOT velocity was 2.4 m/s (IQR, 1.9\u0026minus;2.7 m/s). Median follow-up duration after repair was 46.2 months (IQR, 23.5\u0026ndash;73.5 months). There was one late death in a girl born prematurely (birth weight of 1.79 kg) with multiple genetic problems, including Edwards syndrome, VACTERL (vertebral anomalies, anal atresia, cardiac defects, tracheoesophageal fistula with esophageal atresia, renal anomalies, and limb anomalies) association, bronchomalacia, and a congenital left diaphragmatic hernia requiring surgical repair. TOF was repaired at post-natal 3.5 months (body weight at repair: 3.8 kg) with preservation of PV integrity. Intraoperative measurement of P\u003csub\u003eRV/LV\u003c/sub\u003e was 0.41.Postoperative echocardiography at post-repair 6 months showed RVOT flow velocity of 3.0 m/s with acceptable biventricular function and no PR. Despite excellent postoperative cardiac status, she developed progressive chronic lung disease and died at 7 months after repair. Fourteen patients (14%) required reintervention for significant RVOTO during follow-up, including balloon pulmonary valvuloplasty (BPV, n\u0026thinsp;=\u0026thinsp;6), surgical reintervention (n\u0026thinsp;=\u0026thinsp;4), and BPV followed by surgery (n\u0026thinsp;=\u0026thinsp;4) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e; Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Of the eight patients who required surgical reintervention, seven underwent infundibular muscle resection without transannular patch placement. One patient required implantation of an RV\u0026minus;PA conduit to avoid violation of an anomalous left anterior descending coronary artery crossing the RVOT. Excluding the late death and the RV\u0026minus;PA conduit recipient, significant residual RVOTO (RVOT flow velocity\u0026thinsp;\u0026ge;\u0026thinsp;3.5 m/s) was observed in only one patient (1/98, 1%) on last follow-up echocardiography at median 37.4 months (IQR, 17.0\u0026minus;64.0 months) after repair. Significant PR (\u0026ge;\u0026thinsp;grade III/IV) likewise occurred in one patient (1/98, 1%). Freedom from reintervention for RVOTO was 92.7% at 1 year and 85.0% at 5 years (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). Freedom from significant PR remained 100% at 1 and 5 years and 92.9% at 7 years (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb). On Cox regression, neonatal repair (hazard ratio [HR]: 5.12, 95% confidence interval, CI: 1.32\u0026minus;19.77, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02) and a higher immediate post-repair P\u003csub\u003eRV/LV\u003c/sub\u003e (HR 1.61 per 0.1 increase, CI: 1.03\u0026minus;2.50, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.04) were associated with decreased time to RVOT reintervention (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Receiver operating characteristic curve analysis identified 0.52 as the P\u003csub\u003eRV/LV\u003c/sub\u003e cutoff predicting RVOT reintervention (area under the curve, 0.739; sensitivity, 57.1%; specificity, 87.8%) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Patients with P\u003csub\u003eRV/LV\u003c/sub\u003e \u0026le; 0.52 (n\u0026thinsp;=\u0026thinsp;82, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and those with non-neonatal repair (n\u0026thinsp;=\u0026thinsp;90, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001) had higher freedom from RVOT reintervention than those with P\u003csub\u003eRV/LV\u003c/sub\u003e \u0026gt; 0.52 (n\u0026thinsp;=\u0026thinsp;18) and neonatal repair (n\u0026thinsp;=\u0026thinsp;10) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb).\u003c/p\u003e \u003cp\u003e \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\u003eCharacteristics of patients with RVOT reintervention\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"16\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c14\" colnum=\"14\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c15\" colnum=\"15\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c16\" colnum=\"16\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge at repair (days)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003ePrevious shunt\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003ePreoperative echocardiography\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eMPA patching\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eInfundibular patching\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eIntraoperative measurement\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP\u003csub\u003eRV/LV\u003c/sub\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c12\" namest=\"c11\"\u003e \u003cp\u003ePre-reintervention echocardiography\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003eReintervention\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003eEchocardiography at last follow-up\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePVA (mm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePVA (Z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003ePVA (mm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePVA (Z)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eRVOT flow velocity (m/s)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003ePR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c13\"\u003e \u003cp\u003eBPV\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c14\"\u003e \u003cp\u003eReoperation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c15\"\u003e \u003cp\u003eRVOT flow velocity (m/s)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c16\"\u003e \u003cp\u003ePR\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\u003e#1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;2.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e182\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eIII/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#4\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;3.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;1.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;1.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eI/IV (valved conduit)*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#6\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e178\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;2.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eI/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e115\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;1.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e205\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;3.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;4.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eII/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#10\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e176\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;2.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eI/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#11\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;3.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#12\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;3.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;3.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eII/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#13\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e2.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003eI/IV\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003e#14\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;1.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026minus;1.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003eNone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c16\"\u003e \u003cp\u003etrivial\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"16\" nameend=\"c16\" namest=\"c1\"\u003e \u003cp\u003eBPV, balloon pulmonary valvuloplasty; MPA, main pulmonary artery; PR, pulmonary regurgitation; P\u003csub\u003eRV/LV\u003c/sub\u003e, post-repair pressure ratio of the right ventricle and the left ventricles; PVA, pulmonary valve annulus diameter; PVA (Z), z-score of pulmonary valve annulus diameter; RVOT, right ventricular outflow tract.\u003c/p\u003e \u003cp\u003e\u0026lowast; This patient underwent right ventricle to pulmonary artery conduit implantation to establish a dual RVOT pathway because the left anterior descending coronary artery was crossing the RVOT.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \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\u003eCox regression analysis to identify risk factors for RVOT reintervention\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eUnivariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eMultivariable\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHR (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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\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\u003eSex (male)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.51 (0.70-9.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.16\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAge at repair\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.99 (0.98-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.10\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eNeonatal repair\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.42 (2.78\u0026ndash;25.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.12 (1.32\u0026ndash;19.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBody weight at repair\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.73 (0.52\u0026ndash;1.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.08\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePreoperative PVA (Z) (0.1 increase)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.98 (0.94\u0026ndash;1.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.24\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eIntraoperative PVA (Z) (0.1 increase)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.94 (0.89-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.06\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eP\u003c/b\u003e\u003csub\u003e\u003cb\u003eRV/LV\u003c/b\u003e\u003c/sub\u003e \u003cb\u003e(0.1 increase)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.15 (1.42\u0026ndash;3.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.61 (1.03\u0026ndash;2.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMPA patching\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.79 (0.63\u0026ndash;5.11)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.28\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eInfundibular patching\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.25 (0.63\u0026ndash;8.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.21\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 \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eCI, confidence interval; HR, hazard ratio; MPA, main pulmonary artery; P\u003csub\u003eRV/LV\u003c/sub\u003e, post-repair pressure ratio of the right ventricle to the left ventricle; PVA (Z), z-score of pulmonary valve annulus; RVOT, right ventricular outflow tract.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eSurgical management of TOF has evolved with a growing emphasis on the PVA preservation to alleviate long-term complications such as PR, RV dilation, and ventricular arrhythmia [8.9]. Despite the theoretical advantages of PVA preservation, however, placement of a transannular patch remains common in practice, primarily due to concerns about residual RVOTO [10]. Although previous studies have underscored that PV-sparing or PVA preservation may offer several benefits [8,9,11,12], even minimal interventions on the PV, such as limited commissurotomy, can disrupt the structural integrity of the native valve and lead to progressive PR over time. Unlike conventional valve-sparing techniques that involve some degree of surgical manipulation on the leaflets and commissures, our strategy in patients with relatively sizable PV orifice was to leave the whole native PV structure (i.e. valve annulus, leaflets and commissures) entirely untouched. This approach may yield favorable long-term outcomesࣧbetter preservation of native valve function and prevention of progressive PRࣧultimately reducing the need for late PV implantation [13,14]. A central practical question for applying this seemingly too aggressive valve sparing strategy is, How small is too small?\u003c/p\u003e \u003cp\u003eWhether to preserve the PVA at TOF repair remains debated, particularly regarding the optimal PVA (Z) threshold that guarantees effective PV function while minimizing postoperative RVOTO [5,11,15,16]. In this study, pre-repair PVA (Z) and the intraoperatively measured PVA diameter (or corresponding PVA z-score) did not predict later RVOT reintervention after repair. Instead, intraoperative hemodynamics\u0026mdash;specifically, the post-repair P\u003csub\u003eRV/LV\u003c/sub\u003e\u0026mdash;independently predicted PV reintervention. These findings align with prior reports on the utility of P\u003csub\u003eRV/LV\u003c/sub\u003e in intraoperative decision-making for RVOT reconstruction [5,17].\u003c/p\u003e \u003cp\u003eBecause residual RVOTO is often driven by subvalvar muscle hypertrophy, complete resection of subvalvar aberrant muscle bundles at the initial repair is essential. Inadequate relief of subvalvar obstruction can lead to persistent RVOTO and additional interventions. Notably, none of eight patients who underwent surgical reintervention for RVOTO required conversion to a transannular patch, substantiating the importance of adequate subvalvar resection at the initial operation.\u003c/p\u003e \u003cp\u003eNeonatal repair constituted 10% of the cohort but accounted for more than one-third of RVOT reinterventions. This finding accords with prior reports that neonatal repair confers a higher risk of recurrent RVOTO after primary repair [17,18]. This greater susceptibility of neonates may reflect unfavorable anatomical disposition prompting early repair and technical challenges inherent to small hearts. In this study, most of the reinterventions for RVOTO after neonatal repair were attributed to residual subvalvar obstruction rather than inadequate PVA growth. These observations underscore the need for meticulous relief of subvalvar obstruction at the initial repair in neonates, even when the PVA appears sizable.\u003c/p\u003e \u003cp\u003eIn this cohort, infundibular incisions were performed in approximately two-thirds of patients (66%). Although RV incisions have been implicated in ventricular dilation, dysfunction, and arrhythmias [2], RV remodeling appears to be driven more by the severity of PR rather than by the ventricular incision per se [5,9,11,19]. Infundibular patching is often necessary to achieve complete resection of aberrant subvalvar muscle bundles and a nonrestrictive subvalvar outflow tract. However, aneurysmal dilatation of the infundibulumࣧparticularly in the setting of residual RVOTOࣧremains a concern. To mitigate this risk, we limit the incision to the extent of the deviated conal septum and use stout and rigid patch materials, such as an Acuseal patch.\u003c/p\u003e\n\u003ch3\u003eStudy limitations\u003c/h3\u003e\n\u003cp\u003eThis study had limitations, including its retrospective, single-center design. The relatively short follow-up period limited assessment of long-term outcomes, particularly the risk of progressive RVOTO and PR over longer time frames. Additionally, the decision to preserve the PV structure intact was based on intraoperative surgical judgment, which may have introduced selection bias. Furthermore, the optimal timing and criteria for reintervention remain uncertain, and the detection of RVOTO or PR depends on the timing and frequency of echocardiographic follow-up.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eA substantial subset of TOF patients can undergo repair with PVA preservation and no PV intervention. When significant residual RVOTO occurs, timely catheter-based or surgical reintervention can relieve obstruction without inducing significant PR. Because subvalvar muscle hypertrophy is the principal cause of post-repair RVOTO, complete subvalvar relief at the initial repair is essential when PV integrity is to be preserved intact.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enone\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization: [Tae-Jin Yun], [Seung Woo Ryu] [Eun Seok Choi], [Bo Sang Kwon]; Methodology: [Seung Woo Ryu], [Dong-Hee Kim] [Su Jin Kwon] [Chun Soo Park]; Formal analysis and investigation: [Seung Woo Ryu], [Dong-Hee Kim]: Writing-original draft preparation: [Seung Woo Ryu]; Writing-review and editing [Tae-Jin Yun], [Seung Woo Ryu]: Supervision: [Tae-Jin Yun].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDeclaration of Funding and Competing interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone of the authors has a financial relationship with a commercial entity with an interest in the subject matter of this manuscript or other conflicts of interest to disclose, and no funding was received for this study.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eDisclosure statement:\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors report no financial relationships or other conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding statement\u003c/strong\u003e: No funding was received for this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFrigiola A, Redington AN, Cullen S, Vogel M (2004) Pulmonary regurgitation is an important determinant of right ventricular contractile dysfunction in patients with surgically repaired tetralogy of Fallot. Circulation 110(11 Suppl 1):II153-7. https://doi.org/10.1161/01.CIR.0000138397.60956.c2.\u003c/li\u003e\n\u003cli\u003eGatzoulis MA, Balaji S, Webber SA et al (2000) Risk factors for arrhythmia and sudden cardiac death late after repair of tetralogy of Fallot: a multicentre study. Lancet 356(9234):975\u0026ndash;981. https://doi.org/10.1016/S0140-6736(00)02714-8.\u003c/li\u003e\n\u003cli\u003eTae-Jin Yun (2018) Valve-sparing repair to alleviate pulmonary regurgitation may lead to as much right ventricular dilatation as a transannular patch: A catch-22? J Thorac Cardiovasc Surg 155(3):1174-5.https://doi.org/10.1016/j.jtcvs.2017.09.116. Epub 2017 Oct 7.\u003c/li\u003e\n\u003cli\u003eUebing A, Fischer G, Bethge M et al (2002) Influence of the pulmonary annulus diameter on pulmonary regurgitation and right ventricular pressure load after repair of tetralogy of Fallot. Heart 88(5):510\u0026ndash;4.https://doi.org/10.1136/heart.88.5.510.\u003c/li\u003e\n\u003cli\u003eKim DH, Lee JH, Choi ES, Park CS, Yun TJ (2018) Optimal pulmonary valve annulus diameter for annulus preservation in tetralogy of Fallot may be far smaller than normal annulus size. Semin Thorac Cardiovasc Surg 31(3):253\u0026ndash;63.https://doi.org/10.1053/j.semtcvs.2018.10.014. Epub 2018 Nov 5.\u003c/li\u003e\n\u003cli\u003eChong BK, Baek JS, Im YM et al (2016) Systemic-pulmonary shunt facilitates the growth of the pulmonary valve annulus in patients with tetralogy of Fallot. Ann Thorac Surg 102(4):1322\u0026ndash;8.https://doi.org/10.1016/j.athoracsur.2016.05.064. Epub 2016 Aug 3.\u003c/li\u003e\n\u003cli\u003ePettersen MD, Du W, Skeens ME, Humes RA (2008) Regression equations for calculation of z scores of cardiac structures in a large cohort of healthy infants, children, and adolescents: an echocardiographic study. J Am Soc Echocardiogr 21(8):922\u0026ndash;34.https://doi.org/10.1016/j.echo.2008.02.006. Epub 2008 Apr 11.\u003c/li\u003e\n\u003cli\u003eBacha E (2017) Valve-sparing or valve reconstruction options in tetralogy of Fallot surgery. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu 20:79\u0026ndash;83.https://doi.org/10.1053/j.pcsu.2016.09.001.\u003c/li\u003e\n\u003cli\u003eLatus H, Gummel K, Rupp S et al (2013) Beneficial effects of residual right ventricular outflow tract obstruction on right ventricular volume and function in patients after repair of tetralogy of Fallot. Pediatr Cardiol 34(2):424\u0026ndash;30.https://doi.org/10.1007/s00246-012-0476-4. Epub 2012 Aug 23.\u003c/li\u003e\n\u003cli\u003eClarke NS, Thibault D, Alejo D et al (2023) Contemporary patterns of care in tetralogy of Fallot: Analysis of The Society of Thoracic Surgeons data. Ann Thorac Surg 116(3):768\u0026ndash;77.https://doi.org/10.1016/j.athoracsur.2023.05.035. Epub 2023 Jun 22.\u003c/li\u003e\n\u003cli\u003eStewart RD, Backer CL, Young L, Mavroudis C (2005) Tetralogy of Fallot: results of a pulmonary valve-sparing strategy. Ann Thorac Surg 80(4):1431\u0026ndash;8.https://doi.org/ 10.1016/j.athoracsur.2005.04.016.\u003c/li\u003e\n\u003cli\u003eHoashi T, Kagisaki K, Meng Y et al (2014) Long-term outcomes after definitive repair for tetralogy of Fallot with preservation of the pulmonary valve annulus. J Thorac Cardiovasc Surg 148(3):802\u0026ndash;8.https://doi.org/ 10.1016/j.jtcvs.2014.06.008.\u003c/li\u003e\n\u003cli\u003eKim GS, Han S, Yun TJ (2015) Pulmonary annulus preservation lowers the risk of late postoperative pulmonary valve implantation after the repair of tetralogy of Fallot. Pediatr Cardiol 36(2):402\u0026ndash;8.https://doi.org/ 10.1007/s00246-014-1021-4. \u003c/li\u003e\n\u003cli\u003ePadalino MA, Pradegan N, Azzolina D et al (2020) The role of primary surgical repair technique on late outcomes of tetralogy of Fallot: a multicentre study. \u003cem\u003eEur J Cardiothorac Surg\u003c/em\u003e 57(3):565\u0026ndash;73.https://doi.org/ 10.1093/ejcts/ezz270.\u003c/li\u003e\n\u003cli\u003eAwori MN, Leong W, Artrip JH, O\u0026rsquo;Donnell C (2013) Tetralogy of Fallot repair: optimal z-score use for transannular patch insertion. Eur J Cardiothorac Surg 43(3):483\u0026ndash;6.https://doi.org/ 10.1093/ejcts/ezs372. Epub 2012 Jul 4.\u003c/li\u003e\n\u003cli\u003eChoi KH, Sung SC, Kim H et al (2016) A novel predictive value for the transannular patch enlargement in repair of tetralogy of Fallot. Ann Thorac Surg 101(2):703\u0026ndash;9.https://doi.org/ 10.1016/j.athoracsur.2015.10.050. Epub 2015 Dec 22.\u003c/li\u003e\n\u003cli\u003eAlexiou C, Mahmoud H, Al-Khaddour A et al (2001) Outcome after repair of tetralogy of Fallot in the first year of life. Ann Thorac Surg 71(2):494\u0026ndash;500.https://doi.org/ 10.1016/s0003-4975(00)02444-9.\u003c/li\u003e\n\u003cli\u003eBalasubramanya S, Zurakowski D, Borisuk M et al (2018) Right ventricular outflow tract reintervention after primary tetralogy of Fallot repair in neonates and young infants. J Thorac Cardiovasc Surg 155(2):726\u0026ndash;34.https://doi.org/ 10.1016/j.jtcvs.2017.09.019. Epub 2017 Sep 19.\u003c/li\u003e\n\u003cli\u003eYoo BW, Kim JO, Kim YJ et al (2012) Impact of pressure load caused by right ventricular outflow tract obstruction on right ventricular volume overload in patients with repaired tetralogy of Fallot. J Thorac Cardiovasc Surg 143(6):1299\u0026ndash;1304.https://doi.org/ 10.1016/j.jtcvs.2011.12.033. Epub 2012 Jan 12.\u003c/li\u003e\n\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":"pediatric-cardiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pedc","sideBox":"Learn more about [Pediatric Cardiology](http://link.springer.com/journal/246)","snPcode":"246","submissionUrl":"https://submission.nature.com/new-submission/246/3","title":"Pediatric Cardiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Tetralogy of Fallot, Pulmonary valve annulus, Annulus preservation, Outcomes, Right ventricular outflow tract obstruction","lastPublishedDoi":"10.21203/rs.3.rs-8868645/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8868645/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe optimal post-repair pulmonary valve annulus (PVA) diameter in tetralogy of Fallot (TOF) may be far smaller than anticipated. Therefore, selected patients can undergo repair without manipulating the PV structure. Of the 347 patients who underwent TOF repair with PVA preservation (AP) from January 2016 to December 2023, 100 had AP while leaving the PV structure untouched. Median age, weight, and PVA (Z) at repair were 125 days (interquartile range [IQR], 96.5\u0026ndash;167.5), 6.3 kg (IQR, 5.1\u0026ndash;7.1), and \u0026minus;0.8 (IQR, \u0026minus;1.8 to 0.3), respectively. One non-cardiac late death occurred 9 months after repair. During a median 46.2 months follow-up, 14 patients (14%) required reinterventions for significant right ventricular outflow tract obstruction (RVOTO): balloon pulmonary valvuloplasty (BPV) in 6, surgical RVOTO relief in 4, and BPV followed by surgery in 4 (including 1 who received a right ventricle to pulmonary artery conduit to bypass a left anterior descending coronary artery crossing the RVOT). Except for the conduit recipient, only 2 patients showed significant RVOTO (n\u0026thinsp;=\u0026thinsp;1) and significant pulmonary regurgitation (PR) (n\u0026thinsp;=\u0026thinsp;1) at the last follow-up. On Cox regression, neonatal repair (hazard ratio [HR], 5.12, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.02) and a higher P\u003csub\u003eRV/LV\u003c/sub\u003e (post-repair pressure ratio of the right ventricle to the left ventricle) (HR 1.61 per 0.1 increase, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.04) were risk factors for decreased time to reintervention. The post-repair P\u003csub\u003eRV/LV\u003c/sub\u003e cutoff predicting reintervention was 0.52. Preserving an intact PV during TOF repair is feasible in a subset. Post-repair RVOTO, when it occurs, can be relieved by a timely reintervention without inducing significant PR.\u003c/p\u003e","manuscriptTitle":"Outcomes after tetralogy of Fallot repair with preservation of intact pulmonary valve structure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-22 12:46:57","doi":"10.21203/rs.3.rs-8868645/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-16T19:47:34+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-12T15:47:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"276920517250140743369479557239349368687","date":"2026-03-04T23:06:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"130615926073415834406554939310422366660","date":"2026-03-03T05:36:50+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-01T08:20:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"140874301724590584522958703685993613007","date":"2026-03-01T05:07:00+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-17T10:12:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-14T03:26:54+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-14T03:26:13+00:00","index":"","fulltext":""},{"type":"submitted","content":"Pediatric Cardiology","date":"2026-02-13T07:12:07+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"pediatric-cardiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pedc","sideBox":"Learn more about [Pediatric Cardiology](http://link.springer.com/journal/246)","snPcode":"246","submissionUrl":"https://submission.nature.com/new-submission/246/3","title":"Pediatric Cardiology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"fedf77c0-a4d7-4091-950e-c35e5d69fe7f","owner":[],"postedDate":"February 22nd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-29T15:39:12+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-22 12:46:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8868645","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8868645","identity":"rs-8868645","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}