Is captopril effective in primary pulmonary hypertension?

Several vasodilating agents have been used for the treatment of primary pulmonary hypertension (PPH). However, no effective therapy is currently available for this distressful disease. We tried to use an angiotensin-I converting enzyme inhibitor, captopril, for one woman suffering from PPH. Her initial treatment with furosemide, digoxin and spironolactone had shown little effect. Further administration of captopril improved her clinical condition from NYHA IV to II and made it possible to treat her at our out-clinic. No adverse effect has been found. We would like to appreciate captopril as one of the effective drugs in the treatment of PPH.