Does Down syndrome affect prognosis of surgically managed atrioventricular canal defects?

The appropriateness of surgical correction of complete atrioventricular canal defect in patients with Down syndrome has been questioned on a cost-benefit basis. Our experience with nonselective correction of all patients with atrioventricular canal defects gave us the opportunity to evaluate the impact of Down syndrome on postoperative survival. Between January 1, 1975, and December 31, 1989, we operated on 94 patients with Down syndrome and on 127 genetically normal patients. One hundred thirty-four patients had partial or intermediate atrioventricular canal defect (28% Down patients) and 87 had complete atrioventricular canal defect (74% Down patients). Thirty-two patients died perioperatively and 10 patients died during the 15-year follow-up. The actuarial survival was 90% in the genetically normal patients and 57% in patients with Down syndrome (p < 0.0001). Nonetheless, when the confounding effects of pulmonary vascular resistance and the prevalence of more severe anatomic forms in patients with Down syndrome were eliminated with a multivariable analysis in the hazard domain, Down syndrome was not a significant independent incremental risk factor. This was verified by fitting parametric survival to actuarial survival graphically and by a testing of fit. Patients with Down syndrome underwent fewer reoperations and fared as well as or even better, on clinical and echocardiographic investigation, than their genetically normal counterparts.