Surgical treatment of atrial septal defect in adults: the effect of age at operation on postoperative cardiopulmonary exercise capacity

OBJECTIVES
We investigated the effect of age at the time of atrial septal defect (ASD) closure in adults on cardiopulmonary exercise capacity.

STUDY DESIGN
Fifty-one adult patients (12 men, 39 women; mean age 39 years) underwent surgical repair for isolated ASD. The patients were divided into two groups according to their ages at the time of surgery, i.e. group 1 <40 years, and group 2 ≥40 years of age. Cardiopulmonary exercise capacity was evaluated postoperatively. The results were compared with those of 37 healthy controls (12 men, 25 women; age range 17 to 60 years). The mean follow-up was 2.5±1.3 years (range 1.5 to 5 years).

RESULTS
Postoperatively, an improvement of at least one NYHA functional class was found in 32 patients (62.8%). The incidence of atrial fibrillation remained unchanged (16.1% in group 1, 25% in group 2). Pulmonary hypertension decreased from 22.6% to 16.1% in group 1, and from 45% to 30% in group 2. Compared to controls, peak oxygen uptake (VO2) and all other parameters of cardiopulmonary exercise capacity were significantly lower in the study group. Peak VO2 showed a higher improvement in group 1 than that in group 2 (76.5% vs 68.3% of peak VO2 in age-matched controls). Similarly, patients without pulmonary hypertension had a higher peak VO2 than those with pulmonary hypertension (78.1% vs 64.7% of peak VO2 in age-matched controls). Peak VO2 values of patients who had NYHA class 1, 2, and 3 functional capacity preoperatively were 92.7%, 78.6%, and 52.7% of that in the control group, respectively.

CONCLUSION
Limitations in exercise capacity of adult patients following ASD repair are associated with age at operation, pulmonary artery pressure, and preoperative functional capacity.