Cor Pulmonale: A Disease of the Whole Heart

¹ Laboratory of Clinical Physiology, McLean Hospital, Waverley, Mass.

Although the term "chronic cor pulmonale" is widely used in clinical cardiology, its meaning varies greatly from clinician to clinician. The idea that chronic cor pulmonale is a disease in which the strain is solely on the right ventricle is, however, widespread. Nevertheless, this view has no basis in observation: abnormal physiologic factors present in chronic cor pulmonale are known to increase the work of both ventricles. Thus hypoxia and acidosis by increasing blood flow increase the work of both ventricles equally. However, hypoxia causes pulmonary vasoconstriction, which increases the work of the right ventricle alone. On the other hand, the development of shunts from bronchiolar arteries to pulmonary veins such as occurs particularly in fibrosing pulmonary diseases increases the work of the left ventricle alone.

The manifestations of chronic cor pulmonale are the summation and results of several diverse factors.