The cardiovascular system in cystic fibrosis.

Available evidence indicates that cystic fibrosis causes widespread involvement of the cardiovascular system. Aside from the heart, unusual aberrations have been observed in the bronchial arteries, the aorta, and the systemic capillaries. Of all cardiovascular complications, cor pulmonale is the most serious. Recognition of a significant degree of cor pulmonale is generally possible on the basis of the severity of the underlying disease. Although echocardiography and radionuclide angiography are valuable research tools in the study of cor pulmonale in cystic fibrosis, they add little, from a practical standpoint, to the management of the patient. The basis of cor pulmonale is hypoxemia and unless this is relieved, no enduring effect can be expected from therapy directed toward the heart. Inasmuch as cystic fibrosis is a progressive disease, cor pulmonale is also progressive. At best, cardiac treatment represents a delaying action that may provide more time to combat an intercurrent infection.