Diagnosing pulmonary hypertension  

Pulmonary hypertension can be difficult to diagnose, because symptoms are often similar to other conditions that affect the heart or lungs.

This means there can sometimes be a long delay before a correct diagnosis is made.

However, as pulmonary hypertension can be serious, it's important that you visit your GP if you have symptoms, such as breathlessness and fatigue (extreme tiredness). Your GP will ask about:

  • your symptoms and how they affect your life
  • your family history (some types of pulmonary arterial hypertension may run in families)
  • whether you are currently taking any medication 
  • whether you have any other medical conditions

Your GP may also perform a physical examination, to check for leg or ankle swelling, and listen to your heart and lungs with a stethoscope.


You may have several tests, either to diagnose pulmonary hypertension, or to identify an underlying condition that may be causing it. The initial tests, described below, may be carried out by your GP or a hospital specialist.


An echocardiogram is a type of scan that can determine how well your heart is working.

It uses high-frequency sound waves to create an image of an area inside your body, such as your heart. The image can be used to estimate the pressure in your pulmonary arteries.


An electrocardiogram (ECG) records your heart's rhythm and electrical activity.

A number of small, sticky patches called electrodes are stuck to your arms, legs and chest, and connected with wires to an ECG machine.

Every time your heart beats, it produces tiny electrical signals. The ECG machine traces these signals onto paper.

Chest X-ray

An X-ray is an imaging technique that uses high-energy radiation to highlight abnormalities in bones and other types of tissue.

A chest X-ray can look for other causes of your symptoms, such as scarring in your lungs, which can also cause shortness of breath.

A chest X-ray can also check whether your heart is larger than normal. Pulmonary hypertension makes the right-hand side of your heart work harder, causing it to become enlarged.

Lung function tests

Lung function tests, also known as breathing tests, assess how well your lungs work.

The tests measure how quickly you are able to move air in and out of your lungs, how much air they can hold, and how well they transfer oxygen into your blood and remove carbon dioxide from it.

During the tests, you will be asked to breathe into a lung function machine. The data collected will help diagnose any underlying lung conditions.

Exercise tests

Exercise tests involve carrying out some form of exercise while checking your symptoms.

For example, you may be asked to walk on a treadmill or up and down a corridor for six minutes while your heart rate, blood pressure and oxygen levels are monitored. This can help to determine whether there are any underlying causes of your symptoms.

Ventilation-perfusion scan

A ventilation-perfusion scan measures the amount of air and the blood flow in your lungs. This can be used to look for blood clots in your blood vessels that may be causing pulmonary hypertension.

Blood tests

A sample of blood may be taken and tested to rule out other possible conditions, such as thyroid and liver disease.

Read more about blood tests.

Confirming the diagnosis

The above tests may suggest that pulmonary hypertension is present, but the diagnosis can only be confirmed by measuring your blood pressure in:

  • the right ventricle (lower chamber) of your heart  which pumps blood to your lungs
  • your pulmonary arteries which carry blood from the right side of your heart to your lungs

Your blood pressure is measured using a procedure called right-heart catheterisation.

Right-heart catheterisation

In right-heart catheterisation, a thin flexible tube called a catheter is inserted into a vein in your neck, arm or groin. The catheter is then fed through into the right side of your heart and into your pulmonary arteries.

As well as measuring blood pressure, the catheter can be used to measure the:

  • amount of blood the right-hand side of your heart is pumping out to your lungs 
  • pressure your heart must work against to get blood to your lungs (pulmonary vascular resistance)
  • amount of oxygen in the blood that returns to your heart

If tests reveal an underlying cause, you will be diagnosed with a particular type of pulmonary hypertension. If no cause is found, you will be diagnosed with idiopathic pulmonary arterial hypertension.

Classifying pulmonary hypertension

As part of your diagnosis, your condition will be classified depending on its severity. This will help to determine the best treatment for you.

Pulmonary hypertension is classified into four types, where: 

  • ordinary physical activities do not cause any symptoms
  • ordinary physical activities cause symptoms, such as chest pain or fatigue, but you have no symptoms when resting 
  • even slight physical activities, such as moving your arms, cause symptoms, but you have no symptoms when resting 
  • you have symptoms when resting, which are increased with any type of physical activity

Newborn babies

Newborn babies can have a type of pulmonary hypertension called persistent pulmonary hypertension of the newborn.

This can be diagnosed using some of the same tests used for adults, such as an echocardiogram and right-heart catheterisation.

Media last reviewed:

Next review due:

Page last reviewed: 23/02/2015

Next review due: 23/02/2017