兄妹にみられた原発性肺高血圧症—prazosinとisosorbide dinitrate併用療法を含めて

Primary pulmonary hypertension in brother and sister

　原発性肺高血圧症（PPH）とは原因不明な肺高血圧症の総称であり，成因に関する仮説の1つとして遺伝的素因が想定されている。これは内外あわせて20数家系の報告が，その根拠となっている。そのうち我が国では，4家系8例が知られている。

　今回，我々は20歳代前半に相ついで発生したPPHの兄弟例（兄はすでに他界）を経験した。また妹例ではprazosin （Minipres^R）とisosorbide dinitrate （Nitorol^R）の併用療法によって臨床症状と肺循環動態の改善をみたので報告する。

The patients with primary pulmonary hyper-tension (PPH) noted in brother and sister were reported. Patient 1 is a 26 year old woman who spent daily usual life until three years previously when she initially noted dyspnea on exertion. At 26 year old, cyanosis of the nail beds and edema of lower legs developed after delivery. Although she was diagnosed as PPH in another hospital and treated properly, she was reffered to this hospital for further evaluation and therapy. Right heart catheterization revealed pulmonary artery pressure of 77/33 (mean 46) mmHg, pulmonary artery capillary wedge pressure of 11 mmHg.

Patient 2 is an older brother (24 year old man) of patient 1. He enjoyed good health until 7 months before entry when he initially noted dyspnea on exertion. He developed right heart failure and died 7 months after he was diagnosed as PPH. Pulmonary artery pressure was 80/36 (mean 50) mmHg.

In both patients, electrocardiogram showed right axis deviation and right ventricular hyper-trophy. Chest roentgenogram showed prominence of the central pulmonary artery trunk and decreased peripheral pulmonary vasculature. Neither patient showed immunological ab-normalities.

In patient 1, the combination therapy of daily dosage of prazosin 4 mg and isosorbide dinitrate 20 mg qid was effective : pulmonary artery pressure decreased from 75/27 (42) to 56/20 (34) mmHg and total pulmonary vascular resistance from 688 to 476 dyne sec cm -5 immediately before and 3 months after the therapy without any adverse effects.