Double atrioventricular valve replacement using Melody™ transcatheter valves in an infant with unbalanced atrioventricular septal defect: a case report.

BACKGROUND: To the best of our knowledge, this is the first report of a successful one-stage double atrioventricular valve (AVV) replacement using two Melody™ transcatheter valves in an infant.

CASE SUMMARY: We report a successful case of double AVV replacement with Melody™ transcatheter valves in a 9-month-old infant with a right ventricular dominant atrioventricular septal defect (AVSD). The boy initially presented with borderline sized left-sided heart structures, congenital left AVV stenosis, ventricular displacement of the right AVV with high-grade insufficiency and moderate valvar pulmonary stenosis. Double AVV replacement was performed 2 months after an unsuccessful attempt to repair the defect with persisting left AVV stenosis, underfilling of the small left ventricle and high-grade right AVV, and pulmonary valve regurgitation, resulting in low cardiac output. During double Melody™ AVV replacement, the right ventricular outflow tract was replaced with a pulmonary homograft. The boy was discharged on post-operative Day 28 and presented with competent valves, no ventricular outflow tract obstruction and no paravalvular leak at 11 months of follow-up.

DISCUSSION: The presented innovative approach allowed for biventricular correction of an unbalanced AVSD with unfavourable anatomy for standard techniques. The heart team should decide individualized, after careful assessment of cardiac anatomy and function, if the benefits of replacement of AVVs with Melody™ transcatheter valves may outweigh the benefits of univentricular palliation in case of unbalanced AVSD.