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Pulmonary hypertension
Pulmonary hypertension is defined at right-heart catheterisation (mean pulmonary artery pressure above 20 mmHg), classified into five groups by cause, and treated by group — specific drugs only in pulmonary arterial hypertension (group 1) and in CTEPH.
Why it matters in the exam
Questions test the definitions: mean pressure above 20 mmHg; pulmonary vascular resistance above 2 Wood units; a wedge pressure (PAWP) of 15 or less in the pre-capillary form and above 15 in the post-capillary form — which points to left heart disease, the most common cause. Candidates are asked that echocardiography is the screening test (tricuspid regurgitant velocity above 2.8 m/s), but the diagnosis needs right-heart catheterisation.
Classification and work-up are also asked: group 1 — idiopathic, heritable (BMPR2), drug-induced (appetite suppressants, methamphetamine, dasatinib), connective-tissue disease (mainly scleroderma, where yearly screening is done), HIV, portal hypertension and shunt lesions; group 2 — left heart; group 3 — lung disease and hypoxia; group 4 — chronic obstruction of the pulmonary arteries (CTEPH); and group 5 — mixed mechanisms. The ventilation–perfusion scan is the most sensitive screening test for CTEPH.
In treatment, candidates are asked about vasoreactivity testing (responders are a minority and receive high-dose calcium blockers), initial combination of an endothelin receptor antagonist with a PDE5 inhibitor, adding a prostacyclin at high risk, and the ban on combining PDE5 inhibitors with nitrates. In CTEPH the treatment is surgical pulmonary endarterectomy, balloon angioplasty or riociguat, with lifelong anticoagulation.
Key points
- Definition: mean pulmonary artery pressure above 20 mmHg at right-heart catheterisation.
- PAWP 15 or less — pre-capillary; above 15 — left heart (the most common).
- Screening by echo; ventilation–perfusion scan to exclude CTEPH.
- PAH: endothelin receptor antagonist with a PDE5 inhibitor; prostacyclin at high risk.
- CTEPH: endarterectomy, balloon angioplasty or riociguat, and lifelong anticoagulation.
Summary table
| Group | Causes | Diagnosis | Treatment |
|---|---|---|---|
| 1 — PAH | Idiopathic, heritable, drugs, scleroderma, HIV, portal, shunt lesions | Right-heart catheter: PAWP 15 or less, resistance above 2 Wood | Endothelin receptor antagonist + PDE5 inhibitor; prostacyclin at high risk |
| 2 — Left heart (most common) | Heart failure, valve disease | PAWP above 15 | Treat the heart disease; PAH drugs not recommended |
| 3 — Lung and hypoxia | COPD, interstitial lung disease, sleep apnoea | Lung function, CT | Treat the disease and give oxygen |
| 4 — CTEPH | Previous emboli that did not resolve | Ventilation–perfusion scan, angiography | Endarterectomy, balloon angioplasty, riociguat; lifelong anticoagulation |
| 5 — Mixed | Sarcoidosis, myeloproliferative disease, chronic haemolysis | By the disease | Treat the underlying disease |
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Sources
- ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension, 2022 — Definitions, clinical classification, diagnostic algorithm and treatment of PAH and CTEPH
- Harrison's Principles of Internal Medicine, 21st edition (2022) — Pulmonary Hypertension
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.