The fate of right ventricular dimensions after surgical closure of secundum-type atrial septal defects remains unclear. The objectives of this study were to assess ventricular dimensions, exercise capability, and arrhythmias of patients operated for secundum-type atrial septal defect and compare the results with those in healthy references.

A total of 78 consecutive patients underwent surgical closure for a secundum-type atrial septal defect between 1990 and 1995. In all, 42 patients were included and underwent a cross-sectional evaluation including echocardiography, magnetic resonance imaging, exercise testing, and 24-hour ambulatory electrocardiography. Patients were matched with healthy controls for gender, body surface area, and age.

The mean age at surgery was 4.6 plus or minus 2.8 years, and the mean age at follow-up was 16 plus or minus 3 years. There were no residual intracardiac lesions. The mean right ventricular end-systolic volume was significantly larger in patients (142 ± 26 millilitres) than in references (137 ± 28 millilitres; p = 0.04). In 25% of the patients, right ventricular end-systolic volume was larger than the 95th percentile for references. No relevant arrhythmias were detected. Exercise testing did not reveal differences with healthy references: maximal power (169 ± 43 Watt patients versus 172 ± 53 controls; p = 0.8), maximal oxygen uptake (38 ± 8 versus 41 ± 13 millilitres per minute per kilogram; p = 0.1).

After surgical closure of secundum-type atrial septal defect, right ventricular end-systolic volume is increased. These findings have no impact on rhythm status or exercise capacity at this stage of follow-up, but may have implications for the timing of surgery or the technique of closure if confirmed in longer follow-up.