Incidence, Risk Factors, and Outcomes of Conduction Disturbances After Percutaneous Closure of Perimembranous Ventricular Septal Defects in Children and Adolescents: A Mid-term Follow-up

Background: Conduction disturbance (CD) is a major complication of percutaneous closure of the perimembranous ventricular septal defect (pmVSD). Objectives: This study aimed to investigate the incidence, predisposing factors, and outcomes of sustained CD following percutaneous closure of these defects. Methods: All patients whose pmVSD was closed successfully with percutaneous methods within April 2016 to April 2021 were enrolled in this cohort study. The defects’ size, septal aneurysms, and distance to the aortic valve annulus were determined with transthoracic echocardiography and catheterization. Continuous heart monitoring was performed during the procedures and one hour after, and standard 12-lead electrocardiograms were obtained regularly to determine any CD and arrhythmias. Results: A total of 260 patients who had successful pmVSD closure were enrolled in the study. In this study, 135 (52%) and 125 (48%) patients were male and female, respectively. The mean age of the patients was 75.66 ± 68.89 months. The patients’ median follow-up was 36 months (range: 9-210 months). Thirty-one patients (11.9%) developed sustained CD, and 25 cases recovered to normal conduction. Additionally, 7 patients (2.7%) had several permanent conduction abnormalities, including four right bundle branch blocks, two left bundle branch blocks, and one bi-fascicular block. No one had a permanent atrioventricular block. Closure of non-aneurysmal defects and more prolonged procedures were independent risk factors of CD. Using Amplatzer duct occluder type II was associated with less incidence of conduction abnormalities. Conclusions: The incidence of sustained CD after transcatheter closure was relatively high; however, most cases recovered to normal conduction. The use of softer devices and the placement of devices into the septal aneurysms might lower the risk of CD.