Five groups, defined by the cause rather than the pressure
Expansion
Five groups
- Pulmonary arterial hypertension - idiopathic, heritable, drug induced (appetite suppressants), connective tissue disease (scleroderma), HIV, portal hypertension, congenital shunts (Eisenmenger)
- Left heart disease - the commonest overall. Left ventricular failure, valve disease
- Lung disease and hypoxia - COPD, interstitial lung disease, sleep apnoea, altitude
- Chronic thromboembolic disease
- Multifactorial or unclear - sarcoid, haematological and metabolic disorders
“Group 1 is the arteries, 2 is the left heart, 3 is the lungs, 4 is clot, 5 is everything else.”
Definition is a mean pulmonary artery pressure above 20 mmHg at right heart catheterisation, which remains the diagnostic standard; echocardiography estimates it and screens.
Signs: loud P2, right ventricular heave, raised JVP with giant v waves if there is tricuspid regurgitation, peripheral oedema, ascites and hepatomegaly.
Cor pulmonale is right heart failure resulting from lung disease, so it is the consequence of group 3.
Treatment differs completely by group: group 1 uses endothelin antagonists, phosphodiesterase-5 inhibitors and prostanoids; group 2 requires treatment of the left heart, and vasodilators are harmful; group 3 requires oxygen and treatment of the lung disease; group 4 may be curable by pulmonary endarterectomy.