[Pump function of the left ventricle during the stages of cor pulmonale development]

Cluster analysis was used to examine the nature and magnitude of changes in left ventricular pump function in relation to the severity of primary bronchial obstruction in patients with non-atopic bronchial asthma (n = 45) and chronic obstructive bronchitis (n = 45). In the patients with obstructive lung disease, central hemodynamic changes were found to be determined by the bronchial patency and independent of the pathogenesis of the obstruction. During a remission there was a significant reduction in total peripheral resistance as compared to the values seen in healthy subjects, whereas in moderate or severe obstruction there was a marked increase in total peripheral resistance and a decrease in stroke volume and cardiac output. A drastic bronchial obstruction was followed not only by central hemodynamic changes, but a fall in ejection fraction and a rise in left ventricular end-systolic and end-diastolic volumes.