Pre- and postoperative exercise capacity associated with hemodynamics in adult patients with atrial septal defect: a retrospective study.

OBJECTIVE

This study evaluated the pre- and postoperative exercise capacity in adult patients with atrial septal defect (ASD) associated with hemodynamic variables.

METHODS

Adults (70) with ASD underwent symptom-limited exercise tests. Peak O2 uptake (Peak VO2) and % peak VO2, that is the percentage of predicted value, were measured. These patients were divided into three groups according to pulmonary-to-systemic flow ratio (Qp/Qs) and systolic pulmonary arterial pressure (PAs); Group A: Qp/Qs < or = 3, PAs < or = 50 mm Hg, Group B: Qp/Qs > 3, any PAs, Group C: Qp/Qs < or = 3, PAs > 50 mm Hg. Exercise test was repeated in 22 patients after surgical closure of ASD (mean 4.6 +/- 2.0 months).

RESULTS

Peak VO2 was significantly lower in group B (P < 0.01) and group C (P < 0.01) than in group A (19.3 +/- 5.7, 17.6 +/- 3.6, 27.6 +/- 6.3 ml/min/kg, respectively). In patients except those in group C, there were a weak negative correlation between PAs and % peak VO2 (r = 0.61) and a significant negative correlation between Qp/Qs and % peak VO2 (r = 0.86). Postoperative peak VO2 increased significantly in group A (27.2 +/- 5.1-31.1 +/- 5.1 ml/min/kg, P < 0.05) and group B (16.7 +/- 3.3-21.5 +/- 2.1 ml/min/kg, P < 0.01). However, there was no significant difference between pre- and postoperative peak VO2 in group C (16.8 +/- 1.3-17.8 +/- 2.8 ml/min/kg, NS).

CONCLUSIONS

In ASD patients except those with small or moderate left-to-right shunt and high pulmonary arterial pressure, there was a significant negative correlation between Qp/Qs and peak VO2 corrected by age and gender. Patients with large left-to-right shunt and/or high pulmonary arterial pressure had reduced exercise capacity. However, exercise capacity in patients with large left-to-right shunt increased after closure of ASD regardless of whether they had high pulmonary arterial pressure.