Ostium primum atrioventricular septal defect: an anatomical and surgical review.

The results of surgical repair of ostium primum atrioventricular septal defect show continued improvement. This improvement reflects the advances in open-heart surgery in general and, in particular, the better understanding of the anatomy of the conduction tissue and the morphology and function of the left atrioventricular valve. We have corrected this defect in 84 patients over a ten-year period. There were 2 early deaths (2.4%) and 2 late deaths (2.4%). Two patients had problems related to conduction. Our surgical approach has been to place the interatrial baffle in such a way as to avoid the displaced atrioventricular node and thereby leave the coronary sinus in the left atrium. Our approach to repair of the so-called cleft in the left atrioventricular valve (in reality the space between the ventricular components of the bridging leaflets), is based on the unequivocal triple-leaflet morphology of this valve.