Recognition of residual ventricular septal defect by intraoperative contrast echocardiography

Intraoperative two-dimensional contrast echocardiography was used to detect a residual shunt in 50 patients after surgical repair of ventricular septal defect. Contrast injections were performed following termination of the extracorporeal circulation. In the presence of a shunt the intensity of opacification of both left and right ventricular cavities was compared. In 40 patients no ventricular shunting was observed; insignificant shunting was noted in five patients. Follow-up of these 45 patients proved uneventful. Significant opacification of the right ventricle was noted in five patients. This finding, however, does not necessarily indicate a residual shunt of significant volume. In two patients the residual shunt was confirmed postoperatively by pulsed Doppler echocardiography but clinically there was no need for surgery. Three other patients subsequently required reoperation and partial patch dehiscence was confirmed in all. Thus, intraoperative two-dimensional contrast echocardiography is a sensitive technique to detect a residual ventricular septal defect, an observation which may warrant reoperation before chest closure.