Everything‌ ‌You‌ ‌Need‌ ‌To‌ ‌Know‌ ‌About‌ ‌Pulmonary‌ ‌Hypertension‌ ‌

Pulmonary hypertension (PH) is a rare condition that affects 1%¹ of the global population. It affects the blood vessels that carry blood from the heart to the lungs.

Untreated, PH can cause several life-threatening complications, and some people are more at risk of developing the condition than others.

The condition can’t be cured, but diagnosis and treatment can help manage PH, improve quality of life, and reduce the risk of complications.

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What is pulmonary hypertension?

The heart’s right ventricle pumps blood to your lungs to be oxygenated. Pulmonary hypertension occurs when the pressure in these blood vessels is too high, forcing this part of the heart to work harder than it should and weakening it over time.

The condition is characterized by increased pulmonary arterial pressure of 25mm Hg or higher.²

Types of pulmonary hypertension

The World Health Organization (WHO) has categorized pulmonary hypertension into five categories:³

Group 1: pulmonary arterial hypertension (PAH)

WHO Group 1 PAH occurs when pulmonary vascular resistance increases as the blood vessels thicken, stiffen, or narrow. This causes the right ventricle to work much harder to pump blood through the arteries to reach the lungs and get oxygenated.

This category of pulmonary hypertension may eventually lead to right ventricular heart failure.

PAH can occur for unknown reasons (idiopathic PAH), or it can be linked to genes passed down from family members (heritable PAH).

Some cases of PAH are linked to other health conditions, such as congenital heart disease, liver disease, HIV, portal hypertension (the portal vein supplies blood to the liver), and drug use, including methamphetamines and some diet pills.

Conditions that affect the pulmonary blood vessels (pulmonary veno-occlusive disease and/or pulmonary capillary hemangiomatosis) can also cause PAH.

Group 2: PH caused by left-side heart diseases

This pulmonary hypertension category is caused by problems with the left side of the heart, either with its valves or how it squeezes or relaxes.

It’s typically caused by conditions like valvular disease and systolic or diastolic dysfunction.

Group 2 PH makes your heart less able to keep up with blood coming from the lungs, which causes a backup of blood and increased pressure on the lungs.

Group 3: PH caused by lung diseases

WHO Group 3 is PH caused by chronic lung disease and/or hypoxia (low oxygen levels). Chronic lung diseases that can cause Group 3 PH include:

  • Obstructive lung disease that limits exhalation, like sleep apnea, emphysema, or chronic obstructive pulmonary disease (COPD)

  • Restrictive lung disease that limits lung expansion and makes it difficult to inhale, like interstitial lung disease or pulmonary fibrosis

Pulmonary hypertension occurs when these conditions reduce the flow of oxygenated blood and cause hypoxia, which makes the arteries in the lungs constrict.

Hypoxia without lung disease (as a result of living in high altitudes for a long time, for example), can also contribute to the development of PH.

The elevation of pulmonary pressure is often mild in this category.

Group 4: PH caused by chronic blood clots in the lungs and other types of pulmonary artery blockage

WHO Group 4, also known as chronic thromboembolic pulmonary hypertension (CTEPH), occurs when the body fails to dissolve blood clots in the lungs.

The clots cause scar tissue to form inside the blood vessels connected to the lungs, blocking normal blood flow. This increases the resistance and forces the right side of the heart to overwork.

This category also includes other causes of pulmonary artery blockage, such as congenital pulmonary artery stenosis (narrowing of the arteries).

Group 5: PH caused by unclear complex mechanisms

WHO Group 5⁴ includes PH disorders caused by a combination of factors or unknown reasons, which may include some metabolic disorders like thyroid disease, hemolytic disorders like chronic hemolytic anemia, and splenectomy (spleen removal).

This group also includes systemic disorders, such as sarcoidosis (a rare inflammatory disease) and vasculitis (inflammation of the blood vessels), as well as tumors or kidney disease.

Risk factors for pulmonary hypertension

The following factors increase your risk of developing pulmonary hypertension:

  • Age

  • Living in high altitude areas

  • Use of drugs, including cocaine and methamphetamines

  • Certain medications, including some antiviral, antirheumatic, and diet medications, antidepressants, and chemotherapy

  • Family history of PH

  • Conditions such as liver, lung, and heart diseases

  • History of blood clots in the pulmonary arteries or lungs

  • HIV infection

  • Obesity

Pulmonary hypertension symptoms

Symptom severity varies from one person to another, and diagnosis may be challenging as initial symptoms tend to be mild or unclear.

You might experience the following pulmonary hypertension symptoms:

Dyspnea or shortness of breath

Pulmonary hypertension can cause difficulty breathing, accompanied by rapid breathing or panting. This symptom might be triggered by physical exertion, lying down, or other body position changes, such as sitting, standing up, or bending forward.

Dizziness, fainting, and lightheadedness

You might have dizziness accompanied by lightheadedness, unsteadiness, and a spinning sensation. Your symptoms can be severe enough to cause fainting.

Heart palpitations

With heart palpitations, you might feel as if your heart is racing or feel a fluttering sensation in your chest. This symptom may also appear alongside chest or upper abdomen pain.

Chest pain

A patient may experience shortness of breath and chest pain whenever blood flow to the lungs is needed (during physical activity, for example).

Swollen ankles (edema), legs, face, and abdomen (ascites)

Edema occurs when part of your body swells due to increased fluid volume. This is commonly experienced by people with advanced pulmonary hypertension, and it often affects the ankles or legs.

A swollen abdomen (ascites) is a sign of severe and progressive PH, and is characterized by a build-up of fluid within the abdomen.

Other symptoms

Other PH symptoms include:

  • Fainting

  • Blue lips or fingers

  • Dry cough (sometimes you may see blood stains)

As the condition progresses, you may start to notice symptoms during rest.

How advanced is your pulmonary hypertension?

Medical professionals use the WHO’s functional class system⁵ to work out how advanced and serious your PH is.

WHO Functional Class 1

Pulmonary hypertension does not affect you during ordinary physical activity. In other words, you don’t experience breathlessness, chest pains, tiredness, or faintness when you do everyday activities, like moving around the house, cooking, or going to the shop.

WHO Functional Class 2

You feel normal when you’re resting, but you might find it a little challenging to do everyday physical activities. For example, you might become breathless, tired, have chest pains, or feel like you might faint when you carry out everyday physical tasks.

WHO Functional Class 3

You don’t have any symptoms while resting, but PH is noticeably impacting your ability to carry out daily physical activities, even light ones. For example, you might become breathless, tired, faint, or have chest pains when you climb the stairs, make the bed, or go to the shop.

WHO Functional Class 4

As you start developing signs of right-sided heart failure, you can no longer carry out everyday physical activities without symptoms. You might feel breathless, tired, faint, or have chest pains even when you’re resting.

Pulmonary hypertension complications

Pulmonary hypertension is a serious disease that can affect your everyday life and cause life-threatening complications,⁶ including right-sided heart failure.

Right-sided heart failure occurs when the heart’s right ventricle becomes enlarged and weakened as it tries to pump blood through your narrowed arteries.

Other complications include pericardial effusion (fluid build-up around the heart), blood clots, and arrhythmia (irregular heartbeat).

When to see a doctor about pulmonary hypertension

Early diagnosis is crucial for improving the efficacy of treatment and outcomes, but signs and symptoms of PH are rarely noticeable in the early stages. It could take some time for severe symptoms to appear after the onset of the condition (from months to years depending on your overall health and the underlying causes).

Speak to your doctor if you experience pulmonary hypertension symptoms. Be aware that some symptoms suggest you need urgent medical attention straight away.

Get medical help immediately if you have any of these symptoms:

  • Shortness of breath during rest or activity

  • Chest pain or pressure in the center of your chest or behind your breastbone

  • Wheezing and coughing

  • Heart palpitations, dizziness, or lightheadedness

  • Swelling of the ankles, feet, and legs

How is pulmonary hypertension diagnosed?

Pulmonary hypertension symptoms are similar to symptoms of some lung and heart diseases, making it challenging to get a diagnosis. Your doctor may refer you to a pulmonologist or cardiologist, specialists who can diagnose PH in the following ways:


These tests show the heart’s electrical activity, which can help detect abnormalities. An electrocardiogram will also help your doctor detect signs of strain within the right side of your heart, which could suggest PH.

Blood tests

Blood tests can be used to detect health conditions that may cause pulmonary hypertension. Your doctor or specialist can order several types of tests, including complete blood count, basic metabolic panel, and tests that look at your liver, kidney, and thyroid function.

Right heart catheterization

This is an invasive procedure that provides the most accurate diagnostic test to measure pulmonary blood pressure.

A small tube called a catheter is inserted into one of the large veins in your arm, groin, or neck and is threaded through your body, into the right side of the heart, and into a pulmonary artery. This enables your medical team to measure the pressure in your pulmonary blood vessels.

Lung function tests

Also known as breathing tests, lung function tests are used to assess how your lungs are working and to check for lung conditions like emphysema and asthma.


This is an ultrasound examination of the heart to check the condition and size of its chambers. This test can also measure the pressure in your pulmonary arteries.

6-minute walk test

A 6-minute walk test⁷ measures how far you can walk in a fixed time period and determines how exercise affects your oxygen levels during and after activity.

Chest CT scan

This is an X-ray exam of the heart and the chest area which helps diagnose lung diseases, including interstitial lung disease, pulmonary embolism, cancer, or infections.

X-rays of the heart and lungs

An x-ray of your heart and lungs can assess their general condition.

Genetic tests

Genetic testing shows if you are more at risk of developing PH because it runs in your family.

How is pulmonary hypertension treated?

PH treatment depends on the severity of the condition and its cause.

Common treatment options include:


Your doctor may prescribe medication to treat pulmonary hypertension.


This medication helps to open blocked and narrowed blood vessels in the lungs, improving blood flow and reducing your risk of complications.

Endothelin receptor antagonists

These treat pulmonary hypertension by reducing the amount of endothelin in the blood vessels’ walls, which lowers pressure in the blood vessels.

Endothelin is made in the blood vessel walls, and your body secretes more of this substance if you have pulmonary hypertension. Increased endothelin causes the blood vessel walls to thicken and narrow.

Blood thinners or anticoagulants

Pulmonary hypertension increases your risk of blood clots. Taking blood-thinning or anticoagulant medication can prevent the formation of blood clots and stop them from getting bigger.

Diuretics or water pills

This type of medication helps reduce fluid retention caused by PH.

Other medicines

Your doctor may prescribe digitalis or digoxin to improve the strength of your heart and improve blood flow.

Health and lifestyle strategies

Your doctor may recommend you make changes to your everyday life to help manage pulmonary hypertension and avoid complications.

Although it might not cure the condition, maintaining a healthy lifestyle can help keep your heart, lungs, and blood vessels healthy and improve your response to treatment.

Health and lifestyle strategies for treating PH include:

If you snore loudly or have signs of sleep apnea, talk to your doctor about a sleep study to diagnose the condition and get suitable treatment.

Procedures and therapies

Atrial septostomy

A small opening is made in the heart’s atrial septum to help relieve pressure on the right side of the heart.

Cardiac resynchronization therapy

In cardiac resynchronization therapy (CRT),⁸ a device called a pacemaker is inserted into your chest to improve your heart’s pumping action.

A wire is connected to the device that can detect irregularities in your heart rate. If the device detects an irregularity, it will send electrical impulses to stimulate the heart’s chambers to synchronize and increase blood circulation throughout your body.

Heart or lung transplant

This may be recommended if you have advanced heart or lung failure and other treatments have not successfully improved your condition. It involves removing the diseased heart or lung and replacing it with a healthy one.

The lowdown

Pulmonary hypertension is a rare condition that affects the blood vessels carrying blood to the lungs. With PH, your heart works harder than it should to pump blood to your lungs to be oxygenated, which can cause complications like right-side heart failure.

PH can be hard to diagnose as early symptoms can be unnoticeable or mistaken for other conditions, but various treatments can help relieve symptoms and slow the disease’s progression.

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