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.

Keywords: Adult, age factors, exercise test, heart septal defects, atrial/surgery; oxygen consumption