A Conduction-Sparing Atrial Patch Placement Technique During Atrioventricular Septal Defect Repair

Background Surgical repair of atrioventricular septal defect (AVSD) carries a persistent risk of postoperative complete heart block due to the close proximity of the atrioventricular conduction system to the inferior atrial septum during atrial patch placement. We evaluated a modified atrial patch placement technique designed to minimize conduction system injury during AVSD repair. Methods All patients undergoing AVSD repair between January 2019 and December 2024 were retrospectively reviewed. Patients were stratified according to the atrial patch placement technique. We evaluated a standard approach involving suturing along the inferior atrial septum adjacent to the hinge of the inferior bridging leaflet to the left of the inferior insertion of the atrial septum within the common junction, versus a modified conduction-sparing approach routing the atrial patch along the right atrial wall and around the orifice of the coronary sinus. The primary outcome was the incidence of postoperative complete heart block requiring permanent pacemaker implantation. Results A total of 208 patients underwent AVSD repair. Standard atrial patch placement was used in 132/208 patients (63.5%), and the modified technique was used in 76/208 patients (36.5%). Postoperative complete heart block occurred in 11/132 patients (8.3%) in the standard group and in none of the patients in the modified group. On multivariate analysis, the modified technique remained independently protective (odds ratio 0.022, 95% confidence interval 0.0008-0.61, P = .024). Conclusions A conduction-sparing atrial patch placement strategy during AVSD repair was associated with the elimination of postoperative complete heart block in this cohort.