Repair of complete atrioventricular septal defects “single patch” technique

The first repair of a complete atrioventricular septal defect was performed in 1954 by Lillehei using a single patch technique and controlled cross circulation. Initial results were disappointing with a very high operative mortality and postoperative complications including complete heart block, left ventricular outflow tract obstruction, and persistent or recurrent mitral regurgitation. The single patch technique continues to be frequently utilized with the assistance of cardiopulmonary bypass, moderate hypothermia, and cold blood cardioplegia for myocardial protection. Transesophageal echocardiography is extremely important in assessing the anatomy preoperatively and immediately after the operation is completed. In the single patch technique the common atrioventricular valve is divided into mitral and tricuspid components, and the ventricular septal defect (and subsequently the atrial septal defect) are repaired with a bovine pericardial patch. The leaflets of the newly created left (mitral) and right (tricuspid) valve are resuspended to the pericardial patch, and the “cleft” in the left AV valve is closed with interrupted sutures. Meticulous attention is paid to assuring left AV valve competence. Utilization of these techniques have resulted in a current operative mortality of 2–4% and markedly decreased incidences of LVOT obstruction and complete heart block. Persistent/recurrent mitral regurgitation continues to be a problem in approximately 5–10% of survivors. It is hoped that further refinements of operative technique will result in a decrease in such mitral regurgitation