• Comparison of the effect of ACE-I therapy with that of placebo on left ventricular size [ Time Frame: Measured after six months of therapy ] [ Designated as safety issue: Yes ]
  

• Comparison of the effect of ACE-I therapy with placebo on MR severity, left ventricular geometry, hemodynamics, and signs and symptoms of congestive heart failure [ Time Frame: 6 months on study drug ] [ Designated as safety issue: Yes ]
  
• Evaluation of the early natural history of MR in the six months after repair of an AVSD [ Time Frame: 6 months on study drug ] [ Designated as safety issue: Yes ]
  
• Comparison of the incidence of adverse events occurring in subjects treated with ACE-I therapy to that in subjects receiving placebo (measured after six months of therapy) [ Time Frame: 6 months on safety drug ] [ Designated as safety issue: Yes ]
  

BACKGROUND:

MR causes volume overload and hemodynamic burden on the left ventricle. Initial compensatory mechanisms may fail, leading to increased severity. Patients who have had repair of an atrioventricular septal defect (AVSD) are selected for this study as they have a relatively high incidence of moderate MR and their regurgitant orifice is mobile and dynamic, contributing to the likelihood that they might respond to medical therapy.

DESIGN NARRATIVE:

This is a randomized, double-blind, placebo-controlled trial of ACE-I therapy in children less than 18 years of age with at least moderate MR who are at least 6 months postoperative from repair of an AVSD. A non-randomized Observational Phase enrolled 181 children who were less than 6 months postoperative from repair of an AVSD, who were then evaluated at 6 months for trial eligibility.