Intermediate-term clinical outcomes of primary biventricular repair for left ventricular outflow tract obstruction and ventricular septal defect

Abstract

Objective: Primary biventricular repair for left ventricular outflow tract obstruction and ventricular septal defect remains challenging. The intermediate-term outcomes and risk factors for mortality remain undefined.

Methods: All patients undergoing primary biventricular repair of left ventricular outflow tract obstruction and ventricular septal defect from 1995 to 2008 at the C. S. Mott Children's Hospital, University of Michigan Health Systems were analyzed.

Results: Thirty-one patients (mean age, 18 days; 20 male) with a median follow-up of 6.7 years (range, 0.3-13.5 years) were identified. The ventricular septal defect was enlarged in 15 patients, and a limited atrial septal defect was constructed in 16 patients. There were 6 hospital and 2 late deaths. Ten-year patient survival was 72.3%. Lower body weight (P = .040), complete atrial septal defect closure (P = .026), and longer cardiopulmonary bypass time (P = .026) were risk factors of hospital mortality. An atrial septal defect was patent in 16 patients at discharge, 2 of whom required later surgical closure. Relief of recurrent left ventricular outflow tract obstruction was performed in 1 patient. No patient required pacemaker implantation. Five-year freedom from right ventricle-to-pulmonary artery conduit replacement was 39.3%. Smaller-sized conduit (P = .020) and use of aortic allograft (P = .048) were risk factors for early failure.

Conclusion: Primary biventricular repair for patients with left ventricular outflow tract obstruction and ventricular septal defect provides good early and intermediate-term outcomes. Maintaining a small atrial septal defect may improve hospital mortality. Selective ventricular septal defect enlargement and careful construction of the intraventricular pathway result in a low incidence of recurrent left ventricular outflow tract obstruction, as well as avoidance of heart block. Maximizing valve diameter and avoiding aortic allografts may lengthen conduit longevity.