Pulmonary Hypertension — Beyond Vasodilator Therapy

In 1891, Romberg described the autopsy findings in a patient with unexplained pulmonary hypertension.1 For decades thereafter, case reports and small series added to this original report. About a half-century later, after the introduction of right-heart catheterization in humans, Dresdale showed that the intravenous administration of tolazoline, a systemic vasodilator, could decrease pulmonary vascular resistance in patients with unexplained pulmonary hypertension, which he designated “primary” pulmonary hypertension. Others subsequently tested a variety of systemic vasodilators for their hemodynamic effects and embarked on short trials of therapy.1 However, until the 1990s, the only study in which drugs improved survival was a . . .