Congenital Innovation Session: Hot Topics in Congenital Heart Surgery

Objectives
The Cone procedure (CP) is now the procedure of choice for Ebstein's anomaly (EA). Follow-up studies of surgical treatment of EA demonstrate increased right ventricular (RV) and left ventricular stroke volume, albeit with reduction of the RV ejection fraction in comparison to pre-op assessment. The optimum timing of surgical intervention is unclear.
We advocate for surgery at an earlier age to preserve RV function. This study aims to evaluate the impact of age at surgery on RV functional recovery.
Methods
Patients with EA undergoing surgery were identified in our database. Retrospectively, we measured the postoperative RV fractional area change (FAC) on echo after discharge and at the latest follow up and calculated the delta (∆).
Results
Fifty-five patients underwent operation between 1996-2024 at a median age of 8 years (interquartile range (IQR) 2.6 to 14 y). Preoperative tricuspid regurgitation (TR) was severe in 43 and moderate in 12. EA was an isolated lesion in 49. 22 patients were asymptomatic and 25 were cyanosed at rest or during exercise. Transition from the Carpentier procedure to the CP occurred in 2009. Associated surgical resection of the atrialized portion as opposed to plication was introduced in 2006 and performed in 20 patients. Five patients required a cavopulmonary shunt and 6 underwent a repeat TV repair. Median follow-up was 7.5 years (IQR 3.6 to 13 years). There was no early death, 2 late deaths (patients with complex associated lesions), one proceeded to Fontan completion (Carpentier type D), one underwent heart transplant. Long-term follow up TR: absent or trivial n=10, mild n=31, moderate n=10.
Postoperative FAC improved significantly between early and late follow-up (p=0.0001) and the ∆ between assessments was inversely correlated with age at surgery (n=43) with an average decrease in ∆ FAC of 0.4% per year (95% CI -0.7 to -0.1) p=0.008. An operation at 4.5 years or younger was associated with a 5.8-fold increase in the odds of at least a 10% increase of the FAC over time compared to surgery at an older age (95% CI 1.4 to 26.8) p=0.015. We observed no significant difference between A, B, and C Carpentier classification.
Conclusion
Our data suggest that restoring normal preload and afterload of the RV at an early age in Ebstein's anomaly increases the potential for recovery of the residual RV function. Further prospective studies with iterative post operative cardiac MRI are warranted.

Authors
Federica Caldaroni (1), Edward Buratto (1), Diana Zannino (2), Gavin Wheaton (3), Terry Robertson (4), Patrick Disney (5), Bryn O. Jones (6), Igor Konstantinov (7), Stephanie Perrier (8), Michael M. H. Cheung (9), Christian Brizard (8)
Institutions
(1) Royal Children's Hospital Melbourne, Parkville, Victoria, (2) Murdoch Children's Research Institute, University of Melbourne, Melbourne, VIC, (3) Women and children's hospital, Adelaide, NA, (4) Department of Cardiology, Women’s and Children’s Hospital, Adelaide, NA, (5) Royal Adelaide Hospital, Women's and Children's Hospital, Adelaide, NA, (6) Royal Children's Hospital, Murdoch Children's Research Institute, University of Melbourne, Melbourne, VIC, (7) Royal Children's Hospital, Melbourne, Victoria, (8) Royal Children's Hospital, Parkville, Victoria, (9) The Royal Children's Hospital Melbourne, Parkville, NA 

Objective: This study aimed to investigate the short- and mid-term clinical outcomes of cone repair (CR) in patients with Ebstein's anomaly (EA). In addition, we evaluated the ventricular volumetric and functional outcomes after CR using cardiac CT.
Methods: From 2017 to 2023, 28 consecutive patients with EA who underwent CR performed by a single surgeon were included. The outcomes of interest included development of significant tricuspid valve (TV) regurgitation, reintervention or reoperation for TV dysfunction, and changes in conventional echocardiographic and cardiac CT volumetric measures. CT-derived cardiac strains were measured using multiphase images by the commercially available software to assess the postoperative function of the atrialized right ventricle (RV).
Results: The median age was 14.5 years (IQR: 3.75-51 years). The median follow-up duration was 34 months (IQR: 21-58 months). Atrialized RV plication was not performed during CR in all but one patient. There were no early or late deaths. One patient required reoperation for TV dehiscence 7 months after CR, and the freedom from TV reoperation at 3 years was 90.8%. At the latest echocardiography, the degree of tricuspid regurgitation was mild or less in 26 patients (92.9%). While tricuspid annular plane systolic excursion (TAPSE) significantly decreased immediately postoperatively (p<0.001), it improved over time (p<0.001) at a median interval of 35 months (IQR: 23-57 months) post-operation. In 23 patients (82.1%), CT volumetry was performed both preoperatively and postoperatively (median interval: 31 months, IQR: 34-55 months). The indexed systolic and diastolic RV volumes and stroke volume (SV) significantly decreased after CR (p<0.001), whereas indexed systolic and diastolic left ventricular (LV) volumes and LV SV significantly increased (p<0.001). Multiphasic images were obtained in 10 patients, none of whom underwent atrialized RV plication. The average strain of the atrialized RV was -14.3 ± 4.13%, indicating a reasonably well-functioning chamber.
Conclusions: Cone repair for EA consistently resulted in favorable clinical outcomes, characterized by extremely low mortality and reoperation rates, as well as significantly improved tricuspid valve function. Although RV function decreased immediately following CR, it recovered over time. Post-CR, RV volume decreased while LV volume and SV increased. The atrialized RV was functioning after CR, contributing to the total RV function.

Authors
Dong Hee Jang (1), Chun Soo Park (1), Tae-Jin Yun (1), Bo Sang Kwon (1), Eun Seok Choi (1), Dong-Hee Kim (1)
Institutions
(1) Asan Medical Center, Seoul, Korea 

Objective: This study aimed to compare the clinical outcomes of right ventricular outflow tract (RVOT) reconstruction using bovine jugular vein conduits and polytetrafluoroethylene (PTFE) valved conduits.
Methods: This study included patients who underwent RVOT reconstruction using bovine jugular vein conduits (Group C) and PTFE valved conduits (Group P) between 2013 and 2023. The median follow-up duration was 52.3 months. Conduit dysfunction was defined by either of the following two criteria: significant stenosis (flow velocity ≥ 3.5 m/sec), or significant regurgitation (≥ moderate). Excessive conduit dilation was defined as an increase in conduit diameter by more than 50% of its original size. Propensity score matching was performed using age, body weight, primary diagnosis, McGoon ratio, dual RVOT pathway, and conduit size as covariates. Kaplan-Meier estimates and the log-rank test were used to assess survival rates. Predictors of conduit dilation were determined using the Cox proportional hazards model.
Results: A total of 261 patients were included in the study (172 patients in Group C, 89 patients in Group P). Of these, 100 patients from Group C and 50 patients from Group P were matched using propensity score analysis. In the matched cohort, the median age and body weight at surgery were 9.9 months and 7.5 kg, respectively. The conduit sizes ranged from 12 to 18 mm. No significant differences were observed between Group C and Group P in 5-year overall survival (94.4% vs. 86.5%), conduit explantation-free survival (75.3% vs. 73.8%), or conduit dysfunction-free survival (51.5% vs. 44.3%) (Figure). In patients with smaller conduits (12 and 14 mm), the 5-year conduit stenosis-free survival rate was significantly lower in Group P (38.3% vs. 63.1%, P=0.027). Excessive conduit dilation was observed exclusively in Group C. On multivariable analysis, truncus arteriosus (HR 3.964; 95% CI, 1.553-10.123; P=0.004), the presence of MAPCA (HR 9.310; 95% CI, 3.671-23.611; P<0.001), and conduit size (HR 0.426; 95% CI, 0.289-.0629; P<0.001) were significant predictors of excessive conduit dilation.
Conclusions: The durability of small and medium-sized bovine jugular vein and PTFE valved conduits is comparable in RVOT reconstruction. Smaller PTFE valved conduits are associated with an increased probability of conduit stenosis. Bovine jugular vein conduits carry a risk of excessive dilation in patients with truncus arteriosus, MAPCA, and smaller conduits. 

Introduction:
A better understanding of the morphology of complete atrioventricular septal defects (CAVSD) has impacted on surgical techniques and results. Reoperation rate for residual atrioventricular (AV) valve regurgitation after repair of common atrioventricular canal defect (AVCD) is currently between 5% and 10%.

Objectives:
This video was conducted to evaluate a technique in which neo chords were used to convert of left AV valve cleft into a commissure with sliding plasty on the superior bridging leaflet.

Case Video Summary:
In order to improve the valve components and free up the leaflets, the inferior bridging leaflet attachment to the crest of the septum through Secondary cords were divided. In order to complete the conversion of cleft into a commissure, neo chords were placed between the septum and the superior and inferior Bridging leaflets. sliding plasty was performed on the superior bridging leaflet By Detachment from the annulus and Shifting it more towards the inferior bridging leaflet. Lastly, an annuloplasty was performed.

Conclusions:
This technique yields good anatomical repair. Allowing reconstruction of left AV valves in particular helpful in cases of restricted chordal function and deficient left AV valve tissue. 

Background Surgical septal myectomy is considered the primary therapeutic strategy for obstructive hypertrophic cardiomyopathy (oHCM) in majority of patients who were unresponsive to medical therapy. However, limited data on children and adolescents is currently available, largely due to the technical challenges associated with the operation in this particular age group.
Methods From May 2018 to July 2024, 36 patients with oHCM aged 5 to 18 years underwent conventional transaortic septal myectomy (TASM, n=5) or a novel transapical beating-heart septal myectomy (TA-BSM, n=31). All patients have completed clinical and multimodality imaging evaluations before operation and at 3-month follow up.
Results The age of patients was 13.8±2.9 (Mean ± SD) years and 9 of them (25%) were female. The median preoperative left ventricular outflow tract gradient (LVOTG) was 69 (IQR: 36-85) mmHg. About 67% of the patients had more than moderate mitral regurgitation (MR, TASM n=3, TA-BSM n=21). Both approaches demonstrated equivalent efficacy for resolution of LVOT obstruction, with a median postoperative LVOTG of 24 and 13 mmHg (p=0.14) in the TASM and TA-BSM groups, respectively. At 3-month follow up, the degree of MR was mild in majority of patients in both group (Table), whereas all patients showed improved NYHA class and quality of life. Compared to those in the TASM group, patients in the TA-BSM group experienced shorter operative time, shorter duration of postoperative mechanical ventilation, and shorter ICU stay (Table). The median weight of resected myocardium was 4.9 g in the TASM group and 6.7 g in the TA-BSM group (p<0.01). There was no in-hospital death, septal perforation, and pacemaker implantation in this cohort. One patient converted to urgent thoracoscopic mitral repair due to mitral chordae tendineae fracture during TA-BSM, and showed normal cardiac and valvular function upon 3-month follow-up.
Conclusion TA-BSM is a simple, safe, and effective septal reduction treatment for children and adolescents with oHCM. Compared with TASM, reduced surgical trauma led to quicker postoperative rehabilitation and recovery in the TA-BSM group. Moreover, the TA-BSM approach helps to overcome many challenges posed by the narrowed exposure with related difficulties in children and adolescents during conventional septal myectomy.

Authors
Xiang Wei (1), Yue Chen (2), Jing Fang (3), Yani Liu (4), Song Wan (5)
Institutions
(1) Tongji Hospital, Wuhan, Hubei, (2) Tongji hospital, Wuhan, Hubei, (3) Tongji Hospital, wuhan, China, (4) [email protected], Wuhan, Hubei, (5) Huazhong University of Science and Technology, Wuhan, Hubei 

Objective: Patients with either d- transposition of great arteries (TGA) or L-TGA and native left ventricular outflow obstruction (LVOTO) are at risk for aortic insufficiency (AI) following arterial switch operation (ASO) and LVOT resection due to thin pulmonary artery (neoaortic) wall. We hypothesize that patients with native LVOTO are more likely to develop neo-AI following ASO compared to those with antecedent pulmonary artery banding (PAB).
Methods: A single-institution, retrospective review was performed on 152 patients who underwent arterial switch operation (ASO) with native LVOTO (N=48) or following previous PAB (N=104) between 2010 and 2024. Freedom from reintervention for neo-AI was estimated with the Kaplan-Meier method.
Results: The median age at ASO was 1.4 (0.7–3.0) years in the LVOTO group and 2.0 (1.1–4.3) years in the PAB group, respectively. Simultaneous neo-aortic root reduction at the time of ASO was performed on 13 patients (27%) in the LVOTO group and 35 patients (34%) in the PAB group. Root reduction was performed on patients with larger neo-aortic root Z score (root Z) before ASO (mean root Z; root reduction +, 2.86 vs. root reduction -, -1.03, P <0.001). AI-related reoperation was required in 11 patients (23%) in the LVOTO group and 4 patients (4%) in the PAB group. Freedom from AI-related reoperation at 5 years was higher in the PAB group (PAB group, 92.8 [77.3-97.9]%; LVOTO group, 57.0 [¬31.3–76.2]%; P<0.001). All of the 11 patients who required AI-related reoperation in the LVOTO group demonstrated root Z ≥ -1 before ASO and central AI at the time of reoperation. In these patients, root Z became larger rapidly during admission (mean root Z; post-bypass, -1.16 vs. at discharge, 0.40, P=0.003). In the LVOTO group, when stratified by the combination of root reduction and root Z of -1 before ASO, freedom from AI-related reoperation was 100% in the patients with root Z <-1 (all did not undergo root reduction), 73.3 (24.3–93.4)% in the patients with root Z ≥-1 and root reduction, and 29.8 (6.2–59.0)% in the patients with root Z ≥-1 and without root reduction (P=0.015).
Conclusions: Neo-aortic root expansion occurred quickly, and AI-related reoperation was frequent among the patients with TGA and LVOTO. Simultaneous root reduction may help reduce the reoperation, but further surgical strategy, including LVOTO release plus PAB or root translocation, should be considered for TGA/LVOTO patients.

Authors
Yasuyuki Kobayashi (1), Rebecca Beroukhim (1), Sitaram Emani (1)
Institutions
(1) Boston Children's Hospital, Boston, MA