• Clinical science

Pulmonary hypertension and cor pulmonale

Abstract

Pulmonary hypertension (PH) is elevated pressure in the pulmonary arteries ≥ 25 mm Hg at rest. It can be idiopathic or due to chronic pulmonary (e.g., COPD, chronic sleep apnea) and/or cardiac disease (e.g., mitral valve disease). Over time, the rise in pressure may result in structural changes (e.g., dilation or hypertrophy) or impaired function of the right ventricle. If these changes are secondary to diseases of the lungs or the pulmonary artery system, the condition is referred to as cor pulmonale. While PH and cor pulmonale are often asymptomatic in early stages, symptoms like dyspnea on exertion, fatigue, cyanosis, and syncope appear in later stages. In decompensated cor pulmonale, the risk of arrhythmias and death is high. Echocardiograms are used as an initial non-invasive test to estimate the pulmonary artery pressure and to demonstrate an altered structure of the right ventricle. Right heart catheterization provides the definite diagnosis and the exact mean pulmonary arterial pressure (mPAP). Treatment mainly consists of management of the underlying causes of PH and cor pulmonale. Supplemental oxygen, pulmonary vasodilators, and diuretics may be given to reduce pulmonary artery hypertension and improve blood oxygenation. Lung transplantation is the treatment of last resort in refractory cases.

Definition

References:[1][2][3][4]

Epidemiology

References:[3]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

Classification of pulmonary hypertension (WHO) by cause

Chronic pulmonary and cardiac diseases can lead to pulmonary hypertension!

Cor pulmonale

References:[5][6][2][3][7][4][8][9]

Pathophysiology

Increased pressure in pulmonary circuit → elevated right ventricular afterload → dilatation and/or hypertrophy of the right heartright heart failure and arrhythmias → death.

References:[5][7][10][4][11]

Clinical features

Clinical symptoms may be inconspicuous, especially, in early stages (the symptoms of underlying diseases such as COPD may eclipse those of PH)!

References:[12][5][2][3][13][14][4]

Diagnostics

The diagnostic evaluation of cor pulmonale is inseparable from the evaluation of PH. Testing aims at confirming PH with or without cor pulmonale and determining its severity and underlying pathology.

References:[12][15][13][16]

Treatment

Initial therapy should be directed at the underlying cause of PH or cor pulmonale. Patients with persistent pulmonary hypertension and cor pulmonale despite treatment of the underlying cause should be evaluated for pulmonary vasodilator therapy in a specialized center.

Over-diuresis may result in under-filling of the right ventricle and a decrease in cardiac output, leading to further complications such as prerenal failure!

Therapy should be initiated early before irreversible changes in the pulmonary vessels occur!

References:[3][14][17]