Pre and Postoperative evaluation of the incidence of arrhythmia in patients undergoing corrective intervention for Ebstein anomaly

Background: Patients with Ebstein's anomaly frequently have troublesome cardiac arrhythmias. In particular, this malformation is the most common congenital defect associated with the Wolff-Parkinson-White syndrome. The aim of this study was to investigate the postoperative evolution of arrhythmias without the aid of any surgical techniques for arrhythmia.

Methods: Between 1980 and 1999, 48 patients (22 males, 26 females), with a preoperatively documented arrhythmia, underwent an operation for the correction of Ebstein's anomaly at the Hôpital Broussais. Of these, 24 had paroxysmal supraventricular tachycardia, 12 had atrial fibrillation or flutter, 8 had Wolff-Parkinson-White syndrome, 1 had non-sustained ventricular tachycardia, and the remaining 3 patients had atrioventricular block.

Results: The operative mortality was 8% (4/48). After operation 46% (20/44) of the patients regained permanent sinus rhythm (20/44 vs 2/48, p < 0.01), supraventricular tachyarrhythmia occurred in 16% of the patients (7/44), 8 patients (18%) had atrial fibrillation, and ventricular preexcitation syndrome was present in 3 patients (7%). The incidence of pacemaker implantation for complete heart block was 11% (5/44). Follow-up was achieved in 95% of patients (40/44) who survived the operation and the perioperative period. The mean follow-up was 63 +/- 54 months (range 4-226 months). During this time there were 6 additional deaths. Eight patients continued to have symptomatic arrhythmias (2 had paroxysmal supraventricular tachycardia, 6 had atrial fibrillation), but 55% of patients (20/36) reported no symptoms of arrhythmia (20/36 vs 2/48, p < 0.01).

Conclusions: Surgical repair improves the quality of life of these patients by reducing the incidence of arrhythmias, in fact less than one sixth of patients continued to have postoperative symptomatic arrhythmias. This can be explained by the interruption of accessory pathways that seem to be a major cause of arrhythmia in Ebstein's anomaly.