EFFECT OF PROSTACYCLIN ON MICROVASCULAR PRESSURES IN A PATIENT WITH PULMONARY VENOOCCLUSIVE DISEASE

Continuous-infusion prostacyclin improves symptom scores and decreases mortality in patients with primary pulmonary hypertension, but use of prostacyclin in patients with pulmonary veno-occlusive disease may pr ecipitate pulmonary edema. A patient with pulmonary veno-occlusive dis ease received a graduated intravenous infusion of prostacyclin and pul monary capillary pressures were calculated during prostacyclin dose ra nging. Calculated capillary pressure increased with low-dose prostacyc lin (less than or equal to 6 ng/kg/min) but decreased,vith higher dose s. These data suggest that the post-capillary pulmonary venules in our patient had reversible vasomotor tone, but required a higher dose of prostacyclin to vasodilate than did the precapillary arterioles.