[Reoperation following correction of partial defects of the endocardial cushion (indication, incidence, results)].

In the period between 1955 and 1982, 297 patients underwent surgical correction of a partial AV-canal. Closure of the ostium primum defect was performed either by direct suture or by patch (prosthetic material or pericardium). Only in cases with severe mitral incompetence was the cleft in the anterior leaflet of the mitral valve surgically treated. At an average of 6 years (range: 3 months - 22 years) after the initial procedure 21 patients (7.8 per cent) underwent reoperation. In 20 patients reoperation was necessary for hemodynamic reasons (recurrence of ASD: n = 8; severe AV-valve regurgitation: n = 3; or both: n = 9). One patient with moderate mitral valve incompetence suffered from severe "patch-hemolysis" due to direction of the blood-jet towards the prosthetic patch. Residual or recurrent atrial septal defects were closed by using a patch in cases with previous direct suture (39 patients - 8 reoperations) or by reinsertion or enlargement of the present patch (258 patients - 13 reoperations). AV-valve incompetence could be treated in all cases but two with reconstructive methods. In two patients implantation of a prosthetic valve was necessary. In the single case with "patch-hemolysis" the previous prosthetic patch was replaced by a pericardial one, together with a suture of the mitral cleft 3 months after operation. Mortality of reoperation was 14.5 per cent (3 early deaths). Major complications in the surviving patients did not occur, with one exception: one patient with postoperative total AV-block received a permanent pacemaker.