Incidence of atrial flutter/fibrillation in adults with atrial septal defect before and after surgery

Background. There is controversy about the benefit of surgical repair for atrial septal defect in adults, especially its effect on the incidence of supraventricular dysrhythmias, atrial nutter and fibrillation. We studied their incidence before and after operation. Methods. We examined surface and 24-hour Holter electrocardiograms before, early (between 3 and 7 days), and late (more than 6 months) after operation, performed at age 42.2 years (range, 18.5 to 74.9 years), in 211 adults with atrial septal defect. Patients were arbitrarily divided into three groups: age 18 to 40 years (n = 101), age 40 to 60 years (n = 83), and age more than 60 years (n = 27). All consecutive patients operated on between January 1988 and December 1996 and having a pulmonary to systemic now ratio of 1.5:1 or greater were included in this study. Results, The age of patients without arrhythmias before or after atrial septal defect closure (39 +/- 13 years) was significantly lower than that of patients with flutter (54 +/- 12 years) or fibrillation (59 +/- 8 years). The incidence of atrial flutter was influenced by surgical repair as atrial flutter converted to sinus rhythm late after operation in 10 of 18 patients. However, there was no change in the incidence of atrial fibrillation before (n = 28) and after (n = 21) operation. Conclusions. Our data show that surgical correction of atrial septal defect leads to regression of the incidence of atrial flutter but not fibrillation. Thus, surgical repair of atrial septal defect to abolish supraventricular tachyarrhythmias in adults is warranted, but in patients with fibrillation, it may have to be combined with a Maze operation in the future. (C) 1999 by The Society of Thoracic Surgeons.