Correlation of Acute Prostacyclin Response in Primary (Unexplained) Pulmonary Hypertension with Efficacy of Treatment with Calcium Channel Blockers and Survival

Needed was a prospective, longitudinal study in a relatively large group of patients, where the magnitude of the vasoconstrictive component could be measured acutely and compared to results of long term treatment.

Abstract

Unexplained, or primary, pulmonary hypertension, is usually a rapidly fatal disease, in which the use of vasodilator therapy is controversial (14, 22, 25). While some authors have proposed that there may be a significant vasoconstrictive component to the increased pulmonary arterial pressure and resistance (2, 7, 11, 19), others have indicated that such a component is usually small and/or unimportant (13). This controversy has likely arisen because the disease is relatively uncommon, its pathogenesis is not understood, it is usually diagnosed late in the natural history, and the rate of progression is variable between patients. Yet investigation into the problem is important because persons afflicted are often young and otherwise healthy. Needed was a prospective, longitudinal study in a relatively large group of patients, where the magnitude of the vasoconstrictive component could be measured acutely and compared to results of long term treatment.