Chronic cor pulmonale - Cardiac failure

Chronic cor pulmonale

Definition

Right-sided heart failure resulting from chronic lung disease.

Incidence

Commonest cause of pulmonary hypertensive heart disease.

Sex

M > F

Geography

Related to the extent of cigarette smoking.

Aetiology

The most common cause is chronic obstructive pulmonary disease.

Chronic lung disease: Chronic bronchitis, emphysema, asthma, pulmonary fibrosis, bronchiectasis, cystic fibrosis.

Pulmonary hypertension.

Recurrent pulmonary emboli. Obstructive sleep apnoea.

Pathophysiology

Hypoxia is a potent cause of pulmonary arterial vasoconstriction, this coupled with an effective loss of lung tissue results in progressive pulmonary hypertension and hence increased pressure load on the right ventricle. With time there is compromise of right ventricular function and development of right ventricular failure, often with tricuspid regurgitation.

Clinical features

Pulmonary hypertension, right ventricular failure and the chest disease together produce the clinical picture. Dyspnoea, cyanosis, elevated jugular venous pressure, peripheral oedema and hepatic congestion may occur.

Investigations

The ECG may be normal or may show tall peaked P waves in lead II, right ventricular hypertrophy, right axis deviation or right bundle branch block. The use of chest X-ray, CT scan and lung function tests may help identify the underlying lung disease. Echocardiography is used to exclude left-sided heart failure.

Management

Heart failure should be treated and the underlying lung pathology should be treated vigorously.

Acute chest infections should be treated promptly with antibiotics and steroids where appropriate.

Long-term oxygen therapy has been shown to improve prognosis in hypoxic chronic obstructive airways disease but must be maintained for >18 hours per day.

Atrial fibrillation is a common complication and should be treated appropriately.

Prognosis

This is related to the underlying lung pathology and extent of respiratory failure.