Enlarged right ventricular size at 11 years follow-up after closure of secundum type atrial septal defect in children

Objective

to assess ventricular dimensions, exercise capacity and rhythm-status of patients operated for secundum type atrial septal defect (ASD-II) and compare the results with those in healthy references.

Background

Long-term prognosis of children operated for ASD-II is excellent. It remains unclear whether right ventricular (RV) dimensions completely normalize after surgery and whether this may have implications for (timing of) treatment strategies.

Methods

Seventy-eight consecutive patients underwent surgical closure for ASD-II between 1990 and 1995. Forty-two patients were included in this study and underwent a cross-sectional evaluation including echocardiography, cardiovascular magnetic resonance (CMR) imaging, exercise testing, and 24-hours Holter monitoring. For comparison of the results, ASD-II patients were matched with healthy controls for gender, body surface area (BSA) and age.

Results

Mean age at surgery was 4.6 ± 2.8 years and mean age at follow-up 16 ± 3 years. There were no residual intracardiac lesions. Mean right ventricular end-systolic volume (RVESV) was significantly larger in patients (142 ± 26 ml) than in references (137 ± 28 ml) (p = 0.04). In 25% of the patients, RVESV was larger than the 95^th percentile for healthy controls. No relevant arrhythmias were detected. Exercise testing did not reveal differences between patients and healthy controls. Maximal workload (Watt) was 169 ± 43 for patients vs. 172 ± 53 for controls (p = 0.8), maximal oxygen uptake (ml/kg/min) was 38 ± 8 for patients vs. 41 ± 13 for controls (p = 0.1).

Conclusion

After surgical closure of ASD-II, RVESV 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.