Primary pulmonary hypertension: natural history and the importance of thrombosis.

TLDR

The study aimed to elucidate the natural history and pathogenetic mechanisms of primary pulmonary hypertension. It followed 120 patients retrospectively, all diagnosed by strict clinical and hemodynamic criteria, to gather long‑term data. Only 21 % survived five years; autopsy showed thromboembolic pulmonary hypertension in 57 % and plexogenic arteriopathy in 32 %, and multivariate analysis identified low pulmonary arterial oxygen saturation and anticoagulant therapy as the sole significant prognostic factors, prompting a recommendation for anticoagulation.

Abstract

A long-term retrospective follow-up study was made of 120 patients (33 male, 87 female patients) with primary pulmonary hypertension--diagnosed by strict clinical and hemodynamic criteria--to obtain a better understanding of the natural history and possible pathogenetic mechanisms of the disease. The mean age at diagnosis was 34 (3 to 64) years, but only 24 patients (21%) remained alive 5 years later. Lung tissue obtained at autopsy from 56 patients revealed two major pathologic types: thromboembolic pulmonary hypertension in 32 patients (57%) and plexogenic pulmonary arteriopathy in 18 (32%). Thus, in more than half the patients undergoing autopsy the major histologic feature was thrombi without any evidence of plexiform lesions. The two groups were similar with respect to their clinical and hemodynamic features and short survival. Of the variables tested for prognostic importance by stepwise multivariate analysis, only two were significant: pulmonary arterial oxygen saturation (p less than .00001) and anticoagulant therapy (p = .01). Anticoagulant therapy is recommended for patients with primary pulmonary hypertension.