[Progressive pulmonary hypertension following repair of pseudotruncus arteriosus with major aorto-pulmonary collateral arteries in a 20-year-old patient].

External conduit operation was performed for a 20 year-old woman with pseudotruncus arteriosus with major aorto-pulmonary collateral arteries (MAPCAs). Immediate postoperative pulmonary to systemic peak pressure ratio was 0.70, and decreased to 0.53 on the second postoperative day. She had episodes of pulmonary hypertensive crisis soon after the operation, and injection of tolazoline hydrochloride was effective on them. Seven months after surgery, cardiac catheterization revealed severe pulmonary hypertension (PH) above the systemic level. Pulmonary arterial pressure did not respond to any drug nor to inhalation of oxygen. The progression of PH may be due to the pulmonary obstructive disease, and its causes were thought to be the repetition of constriction of pulmonary arterioles, hypoxia due to the giant bullae, diminished pulmonary vascular beds due to ligation of arborized MAPCAs, and relatively high age at operation.