Vasodilator Treatment of Primary Pulmonary Hypertension

Abstract

Primary pulmonary hypertension has been defined as pulmonary artery hypertension and normal pulmonary capillary wedge pressure with right ventricular hypertrophy for which no aetiology is apparent (1). The clinical diagnosis is made by excluding other causes of pulmonary hypertension, although differentiation from chronic pulmonary thromboembolic disease may be impossible ante-mortem. It predominantly affects young women causing their death after median period of 2 – 3 years (2) although long term follow up (3) and even spontaneous remission (4) have been reported in exceptional cases. Although its cause is unknown the pathological changes include medical hypertrophy and laminar intimai arteriolar fibrosis suggesting a vasoconstrictive element in the genesis of the disease (5). Some cases are familial (6) and as autoimmune disease is present in about the third of cases (7), immunological mechanisms have been suggested in the genesis of the disease. A disease indistinguishable from primary pulmonary hypertension occurred in patients in central Europe who took the weight reducing agent aminorex fumarate (8), and 4 others taking the antidiabetic agent phenformin (9,10).