[Experience with repair of muscular trabecular ventricular septal defects].

We reviewed the records of 9 pediatric patients with muscular trabecular ventricular septal defects undergoing repair between April 1994 and June 1998 (mean age 2.6 +/- 3.1 years, mean weight 9.0 +/- 5.2 kg). The prevalence rate for muscular trabecular defects in the patients undergoing open-heart surgery for congenital heart disease was 2.0%. Although only 6 of the 9 patients were diagnosed as having muscular trabecular defects preoperatively, 60 degrees left anterior oblique and 30 cranially tilted projections of left ventricular cineangiocardiogram were useful to detect these defects. The technique of filling the left heart with blood by stopping to vent the left heart and inflating the lungs during the last one or two ligatures in closure of the defects was also useful to detect these defects intraoperatively. In closure of muscular trabecular defects, division of some trabeculations including a moderator band enabled complete repair through a right atriotomy. The nearer the inferior border of the ventricular septal defects were to the heart apex, the more postoperative residual shunts were left. We consider that apical left ventriculotomy may be needed in apical defects, although the right atrial approach is satisfactory for most muscular trabecular defects.