Repair Of The Left Atrio-Ventricular Valve In Atrio-Ventricular Septal Defect

The operative mortality for atrio-ventricular septal defect (AVSD) has fallen dramatically over the last 15 years as the preferred age of surgery has fallen. For the survivor, the long-term function of the left atrio ventricular valve (LAVV) is crucial in determining quality of life and to avoid re-operation. It is now well established that the zone of apposition (‘cleft’) between the superior and inferior bridging leaflets should be closed at initial repair. What are less well described are the other morphological features of the LAVV and the modes of repair of LAVV variations. This paper describes some of these morphological features and our concepts of the principles involved in LAVV function in AVSD. Important morphologic variants are described and suggestions given for modes of repair. The importance of the quality of LAVV repair for the patient’s future is emphasised.