Influence of chronic pulmonary disease on the heart and circulation

Abstract

1. 1. Studies of both cardiac and pulmonary function were made in forty-eight cases of chronic pulmonary disease. The pathogenesis of pulmonary hypertension and the evolution of chronic cor pulmonale have been considered. 2. 2. Pulmonary arterial hypertension was present at rest in thirty-nine of the forty-eight patients studied. 3. 3. In chronic pulmonary emphysema anoxia was shown to be the important abnormality since it was directly or indirectly responsible for the circulatory complications found in these patients. The reversible nature of these circulatory complications in emphysema was demonstrated and its importance with regard to therapy was stressed. It would appear that in patients with chronic cor pulmonale and emphysema cardiac failure is generally characterized by a high cardiac output. 4. 4. In patients with silicosis and emphysema the pulmonary hypertension is less likely to be reversible since it stems from anatomic alterations in the pulmonary vascular bed rather than from anoxia. When chronic cor pulmonale and cardiac failure develop in this type of patient, the cardiac output is not elevated. This emphasizes the point that chronic cor pulmonale in failure is not always of the high output type. 5. 5. The circulatory changes found in the group of patients with diffusion fibrosis do not appear to be related to anoxia but probably spring from the anatomic lesions produced by the disease processes themselves.