Pulmonary hypertension

• Increased pressure in the pulmonary arteries. Diagnosed when mean pulmonary artery pressure ≥ 25 mmHg at rest.

• Group 1: Pulmonary arterial hypertension (PAH) – idiopathic, hereditary, drug and toxin-induced, associated with other conditions.
• Group 2: Due to left heart disease.
• Group 3: Due to lung disease and/or hypoxia.
• Group 4: Chronic thromboembolic pulmonary hypertension (CTEPH)
• Group 5: Unclear/multifactorial mechanisms.

• Rise in pulmonary vascular pressure, triggered by pulmonary vasoconstriction, leads to vascular wall remodelling and permanent damage to the pulmonary vasculature.

• Idiopathic (unknown cause).
• Heart diseases: left heart failure, valvular disease.
• Lung diseases: COPD, interstitial lung disease.
• Recurrent pulmonary embolism.
• Connective tissue disorders: systemic sclerosis, lupus.
• HIV, liver diseases, congenital heart diseases.

• Dyspnoea on exertion.
• Chest pain, often angina-like.
• Palpitations.
• Syncope (late-stage).

• Signs of right heart failure: Ankle swelling, raised JVP, hepatic enlargement.

• Echocardiography: Estimates pulmonary artery pressure, assesses RV function.
• Right heart catheterisation: Gold standard for diagnosis.
• ECG: Right ventricular hypertrophy, right axis deviation.
• Pulmonary function tests: To exclude lung disease.
• V/Q (Ventilation/Perfusion) scan: To rule out CTEPH.
• CT pulmonary angiography: To assess pulmonary vasculature and exclude other diseases.

• General measures: Oxygen therapy, diuretics for right heart failure, anticoagulation.
• Specific PAH therapies: Calcium channel blockers, endothelin receptor antagonists (e.g. Bosentan), phosphodiesterase type-5 inhibitors, prostacyclin analogues, soluble guanylate cyclase stimulators.
• Surgical: Atrial septostomy, lung transplantation.

• Depends on cause, severity, and response to treatment.
• Idiopathic PAH has a poorer prognosis.
• Monitoring is crucial: functional class, exercise capacity, and echocardiographic findings.

• Worsening right sided heart failure.
• Pericardial effusion and tamponade.
• Sudden cardiac death.
• Infection (e.g. pneumonia).

• Pulmonary hypertension is diagnosed when mean pulmonary artery pressure ≥ 25 mmHg at rest.  
• Pulmonary hypertension is classified into 5 groups.
• Right heart catheterisation is the gold standard method for diagnosis.
• Management includes: oxygen therapy, anticoagulation, diuretics for right sided heart failure, and specific PAH therapies.

Bousseau, S., Fais, R.S., Gu, S., Frump, A. and Lahm, T. (2023). Pathophysiology and new advances in pulmonary hypertension. BMJ Medicine, [online] 2(1). doi:https://doi.org/10.1136/bmjmed-2022-000137.

Mak, S.M., Strickland, N. and Gopalan, D. (2017). Complications of pulmonary hypertension: a pictorial review. The British Journal of Radiology, 90(1070), p.20160745. doi:https://doi.org/10.1259/bjr.20160745.