Arrhythmias after repair of secundum atrial septal defect: the influence of surgical modification.

A retrospective study performed in our institution showed a significant correlation between venous cannulation and the incidence of arrhythmias after atrial septal defect (ASD) repair. We now report the results of a prospective study in 50 children operated on for ASD with selective cannulation of the superior vena cava. ECGs and Holter recordings were made before and after surgery, with a mean follow-up of 2.6 years. We found a significant decrease in postoperative arrhythmias (p less than 0.05) after changing the cannulation technique. Severe arrhythmias, present in 10% of the children in the retrospective group, were not found in the prospective study. Six children had asymptomatic arrhythmias on the Holter recording 1 year after surgery. Three of them, however, already had arrhythmias before the operation. We conclude that the incidence and severity of arrhythmias after ASD repair can be reduced significantly by surgical modifications, at least for the follow-up period of this study. The long-term significance has to be awaited.