Lung function and septal defect surgery

Objectives: To assess pulmonary function and hemodynamic studies in patients with atrial septal defect. Methods: Pulmonary function and hemodynamic studies were made preoperatively in 25 patients. A sequential postoperative follow-up of the pulmonary function was performed on patients at 10 and 50 weeks after surgical repair. Results: All patients had reduced preoperative values for forced vital capacity, forced expiratory volume in one second, peak expiratory flow rate maximal flow after exhalation of 75, 50 and 25% of forced vital capacity, normal single breath carbon monoxide diffusing capacity and no increase in the airway resistance. There was significant correlation between the preoperative pulmonary function parameters and the hemodynamic data. In the early postoperative period (10 weeks), deterioration of pulmonary function was significant and at late postoperative (50 weeks), all patients showed progressive improvement. The patients in the study were divided into two groups according to their mean pulmonary artery pressure, group 1 had a pressure of less than or equal to 15 mmHg and group 2 had a pressure of 16-26 mmHg. Patients in group 2 showed a significant reduction of forced expiratory volume in one second preoperatively and reduced diffusing capacity significantly at late postoperative period. Conclusion: It is concluded that the deteriorated restrictive pattern of pulmonary function in patients with atrial septal defect is correlated to severity of cardiac dysfunction, and is reversible late after surgery.