Prognostic and therapeutic considerations in clinical primary pulmonary hypertension

Twenty-two patients with primary pulmonary hypertension were reviewed to assess the correlation of clinical and haemodynamic features with prognosis. A relationship between resting haemodynamic measurements and survival was sought in all 22 patients, and the effect of vasodilator therapy in 13 was reviewed. Those who survived 12 months or less (seven patients) or 40 months or more (seven patients) from catheterization were classified into short or long survival groups respectively. Clinical, haemodynamic and pulmonary angiographic features of patients in these groups were compared. In the whole group, mean pulmonary artery pressure and pulmonary vascular resistance were inversely related to survival. Multivariate analysis of mean pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR), mean right atrial pressure (RAP), systemic vascular resistance (SVR) and cardiac index (CI) in the whole group identified RAP and PVR as the model which best predicted survival time. The short survival group had a higher prevalence of electrocardiographic evidence of right ventricular hypertrophy, higher mean pulmonary artery pressure and pulmonary vascular resistance than the long survival group. Our experience with vasodilator therapy was less encouraging than that described by other workers. Two of six patients on long-term treatment appeared to stabilize. Two other untreated patients showed spontaneous improvement. Prediction of prognosis in the individual patient is difficult.