Scintigraphic determination of severity in pulmonary parenchymal damage in patients with atrial septal defect.

According to the pattern observed on a lung perfusion scan, patients with atrial septal defect (ASD) were classified into three stages: stage I, normal perfusion (n = 15); stage II, apical prone perfusion (n = 22); and stage III, mottled perfusion (n = 23). These stages were compared with hemodynamic data obtained from cardiac catheterization and with the right ventricular ejection fraction (RVEF). Staging from I to III correlated well with pulmonary arterial pressure, and patients in stage III showed a significant increase in pulmonary arteriolar resistance and a significant decrease in Qp/Qs. There was no significant difference in RVEF between the stages. We concluded that the scintigraphic severity determined by lung perfusion scan could be valid for evaluating the extent of pulmonary parenchymal damage in patients with ASD.