Respiratory dysfunction following acute and chronic pump failure of the heart.

Abstract

In order to explore pulmonary dysfunction originating in cardiac decompensation, acquired heart diseases were classified into three selected categories; chronic compensated heart, chronic decompensated heart and acute decompensated heart with severe alveolar edema. Pathophysiology in each category was investigated. Hemodynamic variables were measured by cardiac catheterizations and a variety of pulmonary functions based on respiratory physiology were studied. Severe alveolar edema due to acute pump failure of the heart revealed a significant inverse correlation between PaO2 and PaCO2 indicating the appearance of decreased effective alveolar ventilation with markedly decreased PaO2. A-aDO2 remained still high despite a complete resolution of alveolar edema. There are some possibilities that pulmonary dysfunction might be accelerated by repetition of acute cardiac decompensation in chronic heart diseases. Chronic pulmonary involvements caused by chronically decompensated heart must be stressed most important for comprehensive treatments of cardiac pump failure. Lung volumes considerably decreased but ordinarily there was no obvious airflow obstruction in the large central airways. Chronic compromised lung with giant left atrium, however, showed appreciable decrease in FEV1% (FEV1/FVC), MMF, V50 and V25, indicating an apparent evidence of both central and peripheral airway obstructions. Patients with CTR over 70% were more seriously involved with a significant reduction in lung volumes in addition to total airway obstructions. Under these situations an inverse correlation between PaO2 and PaCO2 in chronic decompensated heart was observed showing a contrast difference in chronic compensated heart.