Pulmonary hypertension and cor pulmonale in COPD.

Pulmonary artery hypertension (PAH) is the primary cardiovascular complication encountered in chronic obstructive pulmonary disease (COPD). Cor pulmonale can range clinically from mild changes in right ventricular function to frank right heart failure. The prevalence of PAH increases as COPD worsens, and the development of PAH and cor pulmonale appears to affect survival of patients with COPD. Potential causes proposed to explain the development of PAH in COPD include gas exchange abnormalities, destruction of the pulmonary vascular bed, alterations in respiratory mechanics, changes in intrinsic pulmonary vessel tone, and increased blood viscosity. Standard clinical evaluation, including history, physical examination, spirometry, electrocardiography, and chest radiography, is generally inadequate in identifying right ventricular dysfunction. Noninvasive techniques, such as echocardiography, radionuclide ventriculography, and magnetic resonance imaging, have largely replaced invasive pulmonary artery catheterization in the initial assessment of cor pulmonale. The goals of therapy consist of attenuation of PAH, enhancement of right ventricular function, alleviation of clinical symptoms, and improvement in survival. The agents that have been most extensively evaluated for these purposes include oxygen, vasodilators, theophylline, and inotropic medications.