LUNG-FUNCTION AND SEPTAL-DEFECT SURGERY

Objectives: To assess pulmonary function and hemodynamic studies in pa tients with atrial septal defect. Methods: Pulmonary function and hemo dynamic studies were made preoperatively in 25 patients. A sequential postoperative follow-up of the pulmonary function was performed on pat ients at 10 and 50 weeks after surgical repair. Results: All patients had reduced preoperative values for forced vital capacity, forced expi ratory volume in one second, peak expiratory flow rate maximal flow af ter exhalation of 75, 50 and 25% of forced vital capacity, normal sing le breath carbon monoxide diffusing capacity and no increase in the ai rway resistance. There was significant correlation between the preoper ative pulmonary function parameters and the hemodynamic data. In the e arly postoperative period (10 weeks), deterioration of pulmonary funct ion was significant and at late postoperative (50 weeks), all patients showed progressive improvement. The patients in the study were divide d into two groups according to their mean pulmonary artery pressure, g roup 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 re duction of forced expiratory volume in one second preoperatively and r educed 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 correla ted to severity of cardiac dysfunction, and is reversible late after s urgery.