ConditionHeart & circulation
Pulmonary Hypertension
Pulmonary hypertension (PH) is high blood pressure in the arteries of the lungs. The right side of the heart has to work harder to pump blood through them and can eventually fail. The main symptom is breathlessness with exertion, followed by tiredness, chest pain, fainting and leg swelling. PH is most often caused by left-sided heart disease or lung disease, and less commonly by blood clots or a disease of the lung arteries themselves (pulmonary arterial hypertension, PAH). Diagnosis needs a right heart catheterization, and treatment depends on the cause.
Also called: PH, pulmonary arterial hypertension (PAH), high blood pressure in the lungs
At a glance
- What it is
- Raised pressure in the lung arteries: a mean pressure above 20 mmHg at rest on right heart catheterization.
- Five groups
- PAH; left heart disease; lung disease or low oxygen; chronic blood clots (CTEPH); unclear or multiple causes.
- Symptoms
- Breathlessness on exertion, fatigue, chest pain, dizziness or fainting, ankle swelling.
- Diagnosis
- Echocardiogram first; confirmed by right heart catheterization.
- Treatment
- Treat the cause; PAH-specific drugs; surgery or balloon procedures for CTEPH; oxygen, diuretics; lung transplant.
When to get help
Call 911 or go to the ER
- Fainting, especially during exertion
- Severe breathlessness at rest, chest pain or coughing up blood
- Sudden worsening of breathlessness with leg swelling or a racing heart
See a doctor within a day or two
- Breathlessness that is getting steadily worse over weeks
- Rapidly increasing leg or belly swelling, or weight gain of more than 2 to 3 lb (about 1 kg) in a day
- Dizziness or near-fainting with activity
Book a routine appointment
- Unexplained breathlessness or fatigue with exercise lasting more than a few weeks
- Known scleroderma, HIV, liver cirrhosis, sickle cell disease or previous blood clots in the lungs, with new breathlessness
- A family history of pulmonary arterial hypertension
What happens in pulmonary hypertension
The right side of the heart pumps blood through the lungs to pick up oxygen. Normally, this is a low-pressure circuit. In PH, the lung blood vessels become narrowed, stiff, blocked or face back-pressure from the left heart. The right ventricle thickens and enlarges to cope, and over time it can fail (cor pulmonale or right heart failure).
The five groups of pulmonary hypertension
| Group | Name | Common causes |
|---|---|---|
| 1 | Pulmonary arterial hypertension (PAH) | Idiopathic, inherited (BMPR2), drugs and toxins (methamphetamine, some diet drugs), scleroderma and connective tissue disease, HIV, portal hypertension, congenital heart disease |
| 2 | PH due to left heart disease | Heart failure, mitral or aortic valve disease. The most common group |
| 3 | PH due to lung disease or low oxygen | COPD, interstitial lung disease, sleep apnea, high altitude |
| 4 | Chronic thromboembolic PH (CTEPH) | Old pulmonary emboli that did not dissolve |
| 5 | Unclear or multifactorial | Sickle cell disease, sarcoidosis, kidney failure, some blood disorders |
Symptoms
Symptoms develop gradually and are often mistaken for being out of shape or for asthma:
- shortness of breath with activity, later at rest
- fatigue and weakness
- chest pain or pressure, especially with exertion
- dizziness or fainting, particularly during or right after exercise
- swelling of the ankles, legs and belly
- palpitations
- bluish lips or skin in advanced disease
- hoarseness or coughing blood (rare)
Diagnosis
Because symptoms are non-specific, diagnosis is often delayed. Steps include:
- echocardiogram: estimates lung artery pressure and shows right heart strain; the key screening test
- ECG, chest X-ray and blood tests including BNP or NT-proBNP
- lung function tests and chest CT to look for lung disease
- V/Q lung scan to screen for CTEPH, recommended in all patients with unexplained PH
- sleep study if sleep apnea is suspected
- right heart catheterization: a thin tube measures pressures directly in the heart and lung arteries. This confirms PH and its type
- tests for causes: autoimmune antibodies, HIV, liver tests, and genetic testing in some cases
People with scleroderma are screened regularly because their risk of PAH is high.
Treatment
General measures
- diuretics to reduce fluid buildup
- oxygen if blood oxygen levels are low
- anticoagulants for CTEPH
- supervised exercise and pulmonary rehabilitation
- vaccines against flu, COVID-19 and pneumococcus
- avoid pregnancy in PAH because of very high risk; effective contraception and specialist advice are essential
- avoid high altitudes and use supplemental oxygen when flying if advised
Treat the cause (groups 2, 3 and 5)
Optimizing treatment of heart failure, valve disease, COPD, lung fibrosis or sleep apnea is the main treatment for these groups. PAH-specific drugs are generally not recommended for group 2 and are used only selectively in group 3.
PAH-specific medicines (group 1)
Used at specialist PH centers, often in combination:
- endothelin receptor antagonists (ambrisentan, bosentan, macitentan)
- PDE5 inhibitors (sildenafil, tadalafil) or the sGC stimulator riociguat
- prostacyclin pathway drugs (epoprostenol, treprostinil, selexipag), given by continuous infusion, inhalation or tablets
- sotatercept, a newer injectable medicine added to background therapy
- calcium channel blockers for the small number of patients who respond to a vasoreactivity test
CTEPH (group 4)
- lifelong anticoagulation
- pulmonary endarterectomy: surgery to remove old clots, potentially curative
- balloon pulmonary angioplasty for inoperable cases
- riociguat
Advanced disease
Lung or heart-lung transplantation for people who do not respond to medical therapy.
Outlook
Outlook depends on the type, cause and how early treatment begins. PAH was once rapidly fatal, but modern combination therapies have greatly improved survival and quality of life. CTEPH can be cured by surgery in suitable patients. PH due to heart or lung disease reflects the severity of the underlying condition.
Frequently asked questions
What are the first symptoms of pulmonary hypertension?
The first symptom is usually shortness of breath during activity, often with tiredness. Chest pain, dizziness or fainting with exertion, and swelling of the ankles develop as the disease progresses.
What causes pulmonary hypertension?
The most common causes are left-sided heart disease and lung diseases such as COPD and pulmonary fibrosis. Other causes include old blood clots in the lungs, connective tissue diseases, HIV, liver disease, certain drugs, and inherited or unexplained pulmonary arterial hypertension.
How is pulmonary hypertension diagnosed?
An echocardiogram is usually the first test. The diagnosis is confirmed with a right heart catheterization, which measures pressures directly. Other tests, such as lung scans and blood tests, identify the cause.
Can pulmonary hypertension be cured?
Most types cannot be cured but can be managed. CTEPH can sometimes be cured with surgery to remove old clots. Lung transplantation is an option in severe cases. Modern medicines significantly improve symptoms and survival in PAH.
Sources
This guide was written from current patient and clinical guidance, including:
- European Society of Cardiology and European Respiratory Society: 2022 Guidelines for the diagnosis and treatment of pulmonary hypertension
- 7th World Symposium on Pulmonary Hypertension: definitions and classification
- National Heart, Lung, and Blood Institute: Pulmonary hypertension
- American Thoracic Society: Pulmonary hypertension patient information
- Pulmonary Hypertension Association: About PH