Residual shunting in the early postoperative period after closure of atrial septal defect. Echocardiographic comparison of patch materials

Residual shunting after surgical closure of septal defects is a common postoperative complication. In this study, contrast echocardiography was used to assess the effect of different patch materials on early postoperative residual shunting. The study consisted of 44 patients (aged 3 days to 64 years) with simple or complex atrial septal defects. Total pulmonary-to-systemic flow ratios ranged from 1.8:1 to 4.0:1. Three methods were used to close the atrial septal defects: primary suture closure (n = 7), patching with thin, knit Teflon fabric (n = 13), and patching with thicker, low porosity, knit Teflon fabric (n = 24). Contrast echocardiographic injections were performed through central venous and left atrial lines positioned at operation for monitoring purposes. Ten of the 44 patients had residual shunts. In five of them, daily contrast studies showed progressive diminution in shunting with eventual resolution, but in the other five patients, shunting persisted beyond the first 5 postoperative days. Three of the latter five required reoperation for actual residual anatomic defects. No patient whose atrial septal defect was closed by either direct suture or thick, low porosity Teflon fabric had shunting detected at any time postoperatively. Our data confirmed temporary leakage across newly implanted intracardiac patches. However, shunts that persist beyond the first postoperative week indicate true anatomic residua and not porous patch material. If a patient's recovery is complicated, use of contrast echocardiography can determine whether a residual shunt is a causative factor. In patients with complex lesions in whom continued shunting during the early postoperative period may cause serious hemodynamic consequences, heavier, low porosity patch material can be useful.