Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is one form of pulmonary hypertension (high blood pressure in your pulmonary arteries). Symptoms may not appear until the condition has gotten worse. Your provider will run many tests to diagnose you and plan your treatment. PAH medications can improve your quality of life and help you live longer.


What is pulmonary arterial hypertension?

Pulmonary arterial hypertension (PAH) is a condition in which the small blood vessels in your lungs become narrow. As a result, blood can’t flow through your lungs as well as it should. This leads to high blood pressure in your pulmonary arteries. These are the arteries that carry oxygen-poor blood from your heart to your lungs.

Eventually, your heart gets weaker because it has to work harder to pump blood to your lungs. Without treatment, PAH can cause a cascade of problems in your heart, lungs and the rest of your body.

PAH is one form of pulmonary hypertension. This is a general diagnosis for high blood pressure in your pulmonary arteries from any cause.

How does pulmonary arterial hypertension affect my body?

Pulmonary arterial hypertension strains the right side of your heart, which pumps oxygen-poor blood to your lungs. This strain can lead to right-sided heart failure.

Plus, PAH slows down blood flow between your heart and lungs. This means less blood can enter your lungs to gain fresh oxygen. As a result, blood flow to the rest of your body also slows down. So, your organs and tissues can’t get enough oxygen.

Without treatment, PAH can be fatal.

How serious is pulmonary arterial hypertension?

Pulmonary arterial hypertension is a serious condition that can be life-threatening. An early diagnosis and swift treatment can help you live longer and have a better quality of life.


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Who does pulmonary arterial hypertension affect?

Pulmonary arterial hypertension can affect adults at any age. It’s more common among women and people designated female at birth, who are usually diagnosed between age 30 and 60. Men over age 65 who develop PAH are more likely to have severe cases.

PAH can also affect infants. This condition is known as persistent pulmonary hypertension in the neonate (PPHN).

How common is pulmonary arterial hypertension?

PAH isn’t as common as other forms of pulmonary hypertension, including those caused by underlying heart or lung disease. Each year, about 500 to 1,000 people are diagnosed with PAH in the U.S.

In Western countries, about 25 per 1 million people are living with PAH.

Symptoms and Causes

What are the symptoms of pulmonary arterial hypertension?

You may not feel any symptoms early on. Most people with PAH begin to notice symptoms as the condition progresses. These symptoms can include:

  • Blue fingers or lips.
  • Chest pain or pressure.
  • Dizziness or fainting.
  • Fatigue.
  • Racing or pounding heartbeat.
  • Shortness of breath that gets worse over time.
  • Swelling (edema) in your feet and legs, later progressing to your belly and neck.

Without treatment, PAH symptoms continue to get worse over time. You may find it harder to do your usual activities without needing to catch your breath or rest.


What causes pulmonary arterial hypertension?

Damage to the lining of the blood vessels in your lungs leads to pulmonary arterial hypertension. It’s not always clear what causes this damage. When there’s no clear cause, you have what’s called “idiopathic” pulmonary arterial hypertension.

Other times, there is a clear cause. Known causes of PAH include associated medical conditions, genetic mutations and certain drugs.

Medical conditions that may lead to the development of PAH include:

Genetic mutations can also cause pulmonary arterial hypertension. Here’s what we know about genetics and PAH:

  • Mutations in your BMPR2 gene are usually responsible. This gene manages how many cells you have in specific tissues. When there’s a mutation in this gene, you can end up with too many cells in the small arteries of your lungs. This overcrowding of cells narrows the opening of your arteries.
  • PAH can run in families. This is called heritable PAH. About 80% of people with heritable PAH have mutations to their BMPR2 gene.
  • Some people carry an altered gene without ever developing PAH.
  • Some people develop PAH caused by genetic mutations even though they have no family history of the condition. This is called sporadic PAH.

Certain drugs can cause PAH, including:

  • Diet pills like “fen-phen.” This drug isn’t available anymore, since research has shown it’s dangerous. But it may cause PAH many years after you’ve stopped taking it.
  • Recreational drugs like cocaine and methamphetamine.

Diagnosis and Tests

How is pulmonary arterial hypertension diagnosed?

PAH can be hard to diagnose because its symptoms could be caused by many other conditions. Your provider will perform a physical exam and talk with you about your symptoms and medical history. You’ll likely need many tests (including imaging tests and blood tests) to find out if you have pulmonary hypertension and if so, which form.

Your provider may also refer you to a pulmonologist or cardiologist. These specialists will run specific tests to check your heart and lung function. They’ll determine what form of pulmonary hypertension you have (PAH or another form). They’ll also evaluate how far your condition has progressed.

PAH requires specific types of treatment that can’t be used for other forms of pulmonary hypertension. So, your care team must learn as much as possible about what’s happening in your lungs and your heart. This information helps them tailor treatment to your specific diagnosis and needs.

What tests diagnose pulmonary arterial hypertension?

Your care team will use a combination of different tests to rule out other conditions and diagnose PAH.

If your provider suspects you have PAH based on your physical exam, the first test they’ll order for you is a transthoracic echocardiogram. This test evaluates the overall structure and function of your heart.

Other tests may include:

  • Blood tests: To check organ function and hormone levels and identify underlying disorders. Specific blood tests include a complete metabolic panel and complete blood count.
  • Chest CT scan: To check for (and rule out) kidney disease.
  • Chest X-ray: To see if your heart or pulmonary arteries are bigger than they should be.
  • Heart MRI: To evaluate your right ventricle (the chamber of your heart that pumps blood to your pulmonary arteries).
  • Polysomnogram (PSG): To check if you have sleep apnea, which can make PAH worse. A PSG is one type of overnight sleep test.
  • Pulmonary function tests: To check your lung function.
  • Pulmonary ventilation/perfusion (VQ) scan: To check for blood clots in your lungs. This test can rule out chronic thromboembolic pulmonary hypertension.
  • Right heart catheterization: To measure your pulmonary artery pressures. This test is essential for diagnosing PAH.
  • Six-minute walk test: To see how much exercise you can handle and how much oxygen circulates in your blood while you move.

Talk with your provider about the tests you need and how to prepare for them.


What are the criteria for diagnosing pulmonary arterial hypertension?

Providers diagnose pulmonary hypertension based on the blood pressure in your pulmonary arteries. The criteria for diagnosis is pulmonary arterial pressure higher than 20 mmHg while you’re at rest. A right heart catheterization measures this number.

Management and Treatment

What is the treatment for pulmonary arterial hypertension?

Treatment for PAH focuses on slowing down its progression and giving you a better quality of life. There’s no one-size-fits-all approach to PAH treatment. Your provider will work with you to decide the best treatment for your specific needs.

Your individualized treatment plan for PAH may include:

  • Balloon atrial septostomy (BAS). This procedure typically treats babies with congenital heart defects, but it’s also sometimes used for adults with PAH. A septostomy helps take pressure off the right side of your heart and also allows more oxygen to circulate in your blood. It may serve as a bridge to a lung transplant.
  • Calcium channel blockers. These medications help lower the blood pressure in your pulmonary arteries and throughout your body.
  • Diuretics. These “water pills” get rid of extra fluid in your body and reduce swelling.
  • Oxygen therapy. You may need this treatment if you don’t have enough oxygen in your blood. Supplemental oxygen can help people during rest, sleep or exercise.
  • Pulmonary vasodilators. These medications help your pulmonary arteries relax and open up better. This relieves the strain on your heart and helps ease your symptoms.

A last resort option for some people with severe PAH is a lung transplant. This surgery may give you one or two new lungs. A heart-lung transplant gives you a new heart as well.

What medications treat pulmonary arterial hypertension?

Medications that treat PAH come in several different forms:

  • Oral. To help the blood vessels in your lungs relax, and to prevent them from becoming narrow. These medications may help you be more physically active.
  • Inhaled: To treat shortness of breath.
  • Portable infusion pump: To open up your blood vessels so more blood can flow through. This can help improve your symptoms.
  • Intravenous (IV): To open up your blood vessels and relieve symptoms like chest pain and trouble breathing.

The U.S. Food and Drug Administration (FDA) has approved the following drugs for people with PAH:

  • Ambrisentan (oral).
  • Bosentan (oral).
  • Epoprostenol (IV).
  • Iloprost (inhaled).
  • Macitentan (oral).
  • Riociguat (oral).
  • Selexipag (oral).
  • Sildenafil (oral).
  • Tadalafil (oral).
  • Treprostinil (oral, inhaled, infusion pump, IV).

Side effects of PAH medication

Common side effects of drugs that treat PAH include:

  • Feeling lightheaded or like you might faint.
  • Flushing (feeling warm in your head, neck or arms).
  • Gastrointestinal symptoms like bloating, nausea, vomiting and diarrhea.
  • Headache.
  • Hypotension (low blood pressure).
  • Pedal edema (swelling in your feet and ankles).
  • Rash.
  • Upper respiratory congestion.

Specific drugs may have additional side effects. Talk with your provider about how to manage any side effects. In some cases, your provider may need to adjust your dosage.

Can pulmonary arterial hypertension be reversed?

Currently, medications can slow down PAH progression but not reverse the damage already done. However, researchers are working on promising new medications that could help reverse PAH. Such medications would repair damage to the endothelial cells that line your pulmonary arteries.

Talk with your provider to learn more about the latest research and clinical trials for PAH therapies.


What raises a person’s risk of developing pulmonary arterial hypertension?

Risk factors for developing PAH include:

  • Connective tissue disease.
  • Down syndrome.
  • Family history of pulmonary hypertension.
  • HIV.
  • Use of diet medications such as “fen-phen” (dexfenfluramine and phentermine).
  • Use of street drugs.

If someone in your biological family has PAH, ask your provider about genetic testing. If you’re diagnosed with PAH, you may want to tell your family members so they can consider genetic testing.

How can I prevent pulmonary arterial hypertension?

Some risk factors for PAH (like genetic mutations) are beyond your control. However, avoiding street drugs can help lower your risk of PAH and many other health problems. Also, talk with your provider before taking any diet pills.

Depending on your risk factors, your provider may recommend preventive screenings for PAH.

Outlook / Prognosis

What is the outlook for people with pulmonary arterial hypertension?

Thanks to advances in treatment, people with PAH can live longer than ever before. Your life expectancy depends on many factors, including the severity of your condition and how early you’re diagnosed. Talk with your provider to learn your specific prognosis.

It’s important to keep up with your treatment and also closely follow your provider’s guidance. Steps you can take to improve your outlook include:

  • Create an emergency kit. You need to have certain supplies and information with you all the time. Ask your provider what you should include in your kit, and never leave home without it.
  • Get your seasonal vaccines as your provider recommends. It’s important to protect yourself against the flu and pneumonia.
  • Keep all your follow-up appointments. Regular testing is crucial to check your lung and heart function and measure treatment progress.
  • Take your medications as your provider prescribes, and at the same time every day. Don’t make any changes to your medication routine unless your provider tells you to do so.

Living With

What lifestyle changes should I make?

Follow your provider’s guidance for any lifestyle changes you should make. In general, some tips include:

  • Avoid hot tubs, saunas and traveling to areas at a high altitude.
  • Consider birth control options. Pregnancy can be dangerous for people with PAH. Talk with your provider if you’re planning a pregnancy or could become pregnant.
  • Exercise and stay active as much as you can. Talk with your provider about which exercises are safe for you and how much activity you should aim to get each day. Check with your provider before starting any new exercise routine.
  • Follow a heart-healthy diet. This includes eating foods low in saturated fat, trans fat and sodium.
  • Quit smoking and using tobacco products. Also, avoid secondhand smoke.
  • Seek support, and don’t try to handle your PAH journey alone. Ask your provider to recommend support groups and resources.

When should I call my healthcare provider?

Call your provider if you’re having problems with:

  • A fast heart rate (120 beats per minute).
  • A respiratory infection or cough that’s getting worse.
  • Constantly feeling dizzy or lightheaded.
  • Episodes of chest pain or discomfort with physical activity.
  • Extreme fatigue or decreased ability to do your normal activities.
  • Nausea or lack of appetite.
  • Restlessness or confusion.
  • Shortness of breath that’s gotten worse, especially if you wake up feeling short of breath.
  • Swelling in your ankles, legs or stomach that’s gotten worse.
  • Trouble breathing with regular activities or at rest.
  • Weight gain (2 pounds in one day or 5 pounds in one week).

When should I go to the ER?

Go to the emergency department or call your local emergency number if you have:

  • A fast heart rate (120-150 beats per minute) that won’t go down.
  • Fainting spells with loss of consciousness.
  • Complications with your IV or infusion pump. These include infection, catheter displacement, solution leak, bleeding and IV pump malfunction.
  • Shortness of breath that doesn’t go away when you rest.
  • Sudden and severe chest pain.
  • Sudden and severe headache.
  • Sudden weakness or paralysis in your arms or legs.

A note from Cleveland Clinic

Pulmonary arterial hypertension is a life-changing diagnosis. If you or a loved one are newly diagnosed, take time to learn about the condition and what you can expect. Ask your provider for resources that explain how PAH works and how treatment can help.

One of the most important resources you can have is the support of other people in your life. Don’t try to manage your condition alone. If your family and friends don’t live close by, ask your provider about support groups and community resources.

If your loved one was diagnosed, do whatever you can to make them feel supported, and help them connect with others. Illnesses isolate us in some ways, but they can also bring us closer together. Use this time to form a community that can help you or your loved one navigate the path forward.

Medically Reviewed

Last reviewed on 07/22/2022.

Learn more about our editorial process.

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