[Pathophysiology of cor pulmonale]

Chronic cor pulmonale is defined as right-heart hypertrophy or right-ventricular dilatation and/or chronic right-heart failure, secondary to disorders of the respiratory system. Most cases of cor pulmonale are secondary to chronic obstructive pulmonary disease. Other etiologies include restrictive lung diseases (e.g. idiopathic pulmonary fibrosis) and multiple pulmonary emboli, with the important, although small group of patients with chronic major vessel thromboembolism. In some instances abnormal ventilatory drive, disorders of the thoracic cage or neuromuscular diseases will eventually lead to cor pulmonale. Pathogenetic mechanisms involve hypoxic pulmonary vasoconstriction, mechanical narrowing of vessels and obstruction of the pulmonary vascular bed, which are discussed in further detail.