Pathologic Changes of Peripheral Pulmonary Arteries in Ventricular Septal Defect with Pulmonary Hypertension

ABSTRACT

Twelve patients with ventricular septal defect with pulmonary hypertension underwent lung biopsy to assess pulmonary obstructive vascular disease at the time of open heart surgery. According to the Heath and Edwards classification in grading of Pulmonary obstructive vasculr disease, there are eleven cases in grade 1 and one case in grade 3. Thickness of media was measured. It was expressed as percentage of medial thickness to outer diameter of artery. The medial thickness was correlated proportionally with elevation of pulmonary arterial pressure and pulmonary vascular resistance to systemic resistance ratio. In tolazoline test performed in 4 cases, one patients who had pulmonary obstructive vascular disease, had no change of pulmonary vascular resistance to systemic vascular resistance after intravenous injection of tolazoline during cardiac catheterization, but Rp/Rs of three cases was decreased significantly.