Cor pulmonale is the alteration of the structure and function of the right ventricle as the result of a primary respiratory disorder. Pulmonary hypertension generally results from the connection between the primary lung dysfunction and the heart.

Of all patients in the United States with heart disease concomitant with a form of chronic obstructive pulmonary disease (COPD), approximately 6% to 7% will develop cor pulmonale. Exact determination of the incidence of this disease is difficult since not all patients with COPD develop cor pulmonale. The incidence is heavily dependent on “local” conditions, such as local air quality, cigarette smoking, and many other lung disease risk factors.

Numerous pathophysiologic mechanisms may produce pulmonary hypertension (see box below). Cor pulmonale is a subsequent pathophysiologic development. The involvement of the right ventricle is somewhat different, depending on whether the underlying condition is chronic or acute. In chronic cor pulmonale, the right ventricle hypertrophies over time; in an acute development situation, the right ventricle becomes dilated to the point of dysfunction.