Explain Sinus Venosus Defect with Partial Anomalous Venous Connection ?
In this defect the atrial septal defect is situated just below the orifice of superior vena cava above the limbus tissue. It is usually associated with anomalous connections of right superior pulmonary vein to the SVC or its junction with the right atrium.
Initial steps of the operation are not different from those described for secundum defect. Pericardium is harvested. Care should be taken while taping SVC above all the pulmonary veins joining anomalously. Direct cannulation or the SVC high up or at its junction with innominate vein will be required. In some cases direct cannulation of innominate vein with a right-angled cannula is preferable. The patient is connected to cardio pulmonary bypass, aorta clamped and cold cardioplegia administered to the aortic root. Caval tapes are snared and atriotomy done which is extended superiorly away from the sinoatrial node without injuring it. Pericnrdial baffle is sutured to direct pulmonary venous blood into the left atrium. Care is taken not to narrow the pulmontlry venous opening to tlie lelt atrium. At times SVC needs widening and this call be achieved by pericardial patch or from right atrial tissue as a V-Y plasty. Inferior vena caval defect with anomalous connection of inferior pulmonary vein is corrected in a similar manner using pericardial baffle.