Dilemmas in atrioventricular septal defect repair

Abstract

This thesis reports upon clinical outcomes of atrioventricular septal defect (AVSD) repair and of left atrioventricular valve (LAVV) replacement in neonates, infants and adults and reports upon outcomes hypoplastic left heart complex (HLHC) repair. Complete AVSD is a congenital heart defect and consists of a ventricular septal defect (VSD), an atrial septal defect, and a single or common AV valve orifice. One of our analysis revealed that presence of residual lesions before discharge, as measured by a technical performance score, was accurately able to identify AVSD patients who had complications, prolonged days on a ventilator, and required post-discharge reinterventions. Residual AV valve regurgitation and abnormal conduction at discharge were among the subcomponents strongly associated with reinterventions. Another study shows that AVSD subtype is associated with timing of LAVV replacement. In complete AVSD, LAVV is typically replaced within a few years after AVSD repair whereas in patients with partial AVSD, replacement was performed much later (> 10 years after initial surgery). Analysis of outcomes after mitral valve replacement with 15-17 mm mechanical prostheses revealed that small sized mechanical prosthesis may be an important treatment option in critically ill neonates and infants. In another study we were able to show that VSD in AVSD can be safely closed with untreated autologous pericardium. In our cohort of HLHC patients, all left-sided heart structures showed catch-up growth after biventricular repair. Growth rate was most prominent during the first year after repair with lower growth rate of the mitral valve compared to the aortic valve.