Left ventricular outflow tract obstruction due to tricuspid valve prolapse through a high ventricular septal defect.

A rare case is described of fixed subaortic obstruction due to a prolapsed redundant fibrous septal leaflet of the tricuspid valve, herniated through a membranous ventricular septal defect in a boy aged 11 years. The type of obstruction was not suspected before surgery and there was no shunt through the septal defect. Left ventriculography, was attempted and abandoned due to dangerous arrhythmia. Echocardiogram showed definite fixed subvalvular left ventricular outflow obstruction. Corrective surgery was carried out through aortotomy and right ventriculotomy. Ruptured chordae were resected and the tricuspid valve was replaced into the right ventricle. Redundant fibrous tissue was used to close the septal defect. The postoperative recovery was uneventful after complete AV block in the first 5 days.