Gold standard case presentation

Cor pulmonale

Cor pulmonale is better termed pulmonary arterial hypertension (PAH) secondary to intrinsic or extrinsic lung pathology. It is not possible to determine the true prevalence of cor pulmonale due to the fact that right heart catheterization in everyone who is suspected of having cor pulmonale is not feasible. However figures can vary from 20% to up to 90%. The most common lung disease that we see causing right heart failure is in severe COPD patients.

Cor pulmonale is due to vasoconstriction of the pulmonary vasculature secondary to hypoxia or a primary reduction in the vasculature of the pulmonary system from, for example emphysema. This leads to an increased blood viscosity and pulmonary blood flow that can then lead to PAH.

It is also important to note that PAH with and without left ventricular failure are different and difficult to manage.

Causes of cor pulmonale:

• Lung disease
• COPD (most commonly)
• cystic fibrosis (younger patients)
• interstitial lung diseases
• Pulmonary circulation disease
• acute or more commonly chronic pulmonary embolic disease
• primary pulmonary hypertension
• Neuromuscular disease
• amyotrophic lateral sclerosis
• myasthenia gravis
• Poliomyelitis
• bilateral diaphragmatic paralysis
• Thoracic cage deformities
• kyphoscoliosis

Clinical features (difficult to diagnose purely clinically):

• classic loud P2 S3 gallop rhythm
• tricuspid regurgitation
• peripheral pitting oedema (if concomitant left heart failure also present)

Investigations

• baseline blood tests including brain natriuretic peptide
• lung function tests
• plain chest radiograph
• increased size of right descending pulmonary artery
• electrocardiogram
• Right axis deviation
• P-pulmonale
• incomplete or complete right bundle branch block
• echocardiogram
• cardiac MRI
• right heart catheterization

Management

Many medications are licensed for the management of PAH, however, there is no specific data on the optimal management course.

• oxygen therapy
• long-term home oxygen therapy in hypoxic COPD patients does improve survival
• Medications
• digoxin if there is concomitantly atrial fibrillation
• vasodilators including nitrates and ACE inhibitors