Significance of lung biopsy in determining surgical indication in cases of congenital cardiac anomalies with pulmonary hypertension.

Correlation between the grade of pulmonary arterial change and pulmonary arterial pressure was studied in 60 patients with congenital cardiac anomalies associated with pulmonary hypertension. Of the 60, 45 specimens of pulmonary arteries were obtained by autopsy and 15 by biopsy. Pulmonary arterial pressure was correlated with the products of the medial thickness and intimal lesions of small pulmonary arteries both in the autopsy and in the biopsy specimens. Also, medial thickness and intimal lesions were independently correlated to the pulmonary arterial pressure. However, the regression equation was not identical among the kinds of diseases, although significant correlation was found between the degree of intimal lesions and pulmonary arterial pressure. Medial hypertrophy was reversible after corrective surgery, but intimal lesions were irreversible except for cellular proliferation. Therefore, to determine the indication for corrective surgery, it should be emphasized that intimal change of the small pulmonary arteries should be carefully evaluated. Since the degree of intimal lesions is not accurately diagnosed from hemodynamic parameters alone, diagnosis of intimal lesions by lung biopsy is indispensable to determine the possibility of corrective surgery in the congenital heart disease with severe pulmonary hypertension.