Mitral and tricuspid valve closure in congenital heart disease.

Echocardiography was used to evaluate mitral and tricuspid valve closure in patients 1 day to 20 years of age. When possible, simultaneous phonocardiograms were obtained. The difference in time between the Q wave of the electrocardiogram and mitral closure and between Q and tricuspid closure was designated the delta value. Four groups of patients were assessed: 1) normals (40), secundum atrial septal defect (ASD) (10), mitral valve prolapse syndrome (Barlow's syndrome) (13), pulmonary hypertension (12), and pulmonic stenosis (6); 2) Ebstein's anomaly (10); 3) transposition of the great vessels (15); 4) right bundle branch block (RBBB) (25). Ten patients with surgically induced right bundle branch block were studied by phonocardiography alone. Group I had values of 50 msec or less (-5 to 50 milliseconds) and served as controls. Ebstein's anomaly showed prolongation of the delta value to 65 msec or greater in eight out of ten patients. Patients with transposition of the great vessels showed a striking difference from the preceding groups in that an average negative delta value was obtained. Twenty-two patients of group 4 (RBBB) had delta values within the normal range. This study has shown that a delta value greater than 65 msec is suggestive of Ebstein's anomaly. In addition, if the delta value is negative, transposition of the great vessels can be suspected.