What is pulmonary hypertension?
Pulmonary hypertension is where you have high blood pressure in your pulmonary arteries. These are the blood vessels that go to your lungs.
It’s a rare condition, affecting 7000 to 8000 people in the UK. Pulmonary hypertension can affect people of all ages, including babies and children.
Pulmonary hypertension is not the same as high blood pressure (systemic hypertension), which is measured by a cuff on your arm.
If you have pulmonary hypertension:
- your pulmonary arteries get stiff and narrow
- blood cannot flow well through your arteries
- your heart has to work harder to pump blood.
Pulmonary hypertension is a serious condition and cannot usually be cured. But there are treatments that can reduce your symptoms and help you manage your condition.
There are five main groups of pulmonary hypertension, as it can be caused by different things.
Pulmonary Hypertension Association UK (PHA-UK) has a helpful video explaining pulmonary hypertension and how it affects the body.
Symptoms of pulmonary hypertension
The main symptoms of pulmonary hypertension include:
- breathlessness
- feeling very tired
- chest pain
- palpitations (a racing heartbeat)
- swollen ankles, legs or tummy
- feeling dizzy or fainting.
You may look well with pulmonary hypertension and only notice symptoms when you do everyday activities, like climbing the stairs.
If you have a type of pulmonary hypertension called pulmonary arterial hypertension (PAH) you may not have symptoms at first. The symptoms may start once you’ve had the condition for some time.
You can speak to your GP if you’re worried about symptoms, like feeling breathless when you’re active or feeling very tired.
They can check if your symptoms could be due to other conditions. For example, breathlessness is also a symptom of other lung conditions, including asthma, COPD (chronic obstructive pulmonary disease) and pulmonary fibrosis.
If they think you could have pulmonary hypertension they can refer you for more tests.
The sooner you see your GP and get a referral, the quicker you can get diagnosed. Early diagnosis is important so you can start treatment, improve symptoms, and stop your pulmonary hypertension getting worse.
Types and causes of pulmonary hypertension
Pulmonary arterial hypertension (PAH) affects the smaller branches of the pulmonary arteries. It can be a complication of other conditions including:
- scleroderma and some other connective tissue diseases
- liver disease
- congenital heart defects (heart problems you’re born with)
- sickle cell disease
- HIV.
Certain medicines and recreational drugs have also been shown to increase the risk of developing PAH.
PAH can be passed down from your parents, but this is very rare.
If there’s no known cause for your PAH it’s called ‘idiopathic PAH’.
Left heart disease, such as mitral valve problems, is a common reason why people get pulmonary hypertension.
If you have a problem with the left side of your heart, the right side has to work harder to pump blood through your lungs. This increases the blood pressure in the pulmonary arteries in your lungs.
When oxygen levels are low, the pulmonary arteries get narrow. This means blood cannot flow freely causing high blood pressure in the arteries.
Pulmonary hypertension is more common in people who have a lung condition, like COPD or interstitial lung disease.
Both conditions can reduce the amount of oxygen in the blood, and cause the lung blood vessels get tight and narrow, causing hypertension in the pulmonary arteries.
Other conditions that reduce the amount of oxygen getting to your lungs include:
Pulmonary hypertension caused by blood clots is called chronic thromboembolic pulmonary hypertension (CTEPH).
A blood clot blocking one of the blood vessels supplying your lungs is called a pulmonary embolism). A pulmonary embolism usually dissolves well with anticoagulant drugs.
With CTEPH, a blood clot does not dissolve and forms scars in your pulmonary arteries instead. The scars block the flow of blood and cause more pressure in the lungs.
This type of pulmonary hypertension has more rare causes. They’re grouped together because their causes are less clear, or because there’s more than one cause.
Some of the rarer causes of pulmonary hypertension include:
- sarcoidosis and other conditions that cause inflammation, like vasculitis
- chronic kidney disease
- blood disorders, like sickle cell disease
- compression of the arteries in the lungs (for example, as the result of a tumour).
Risks and complications from pulmonary hypertension
Some of the risks from pulmonary hypertension include:
- heart failure
- complications with surgery and general anaesthetic
- complications during pregnancy and birth
- air travel can make symptoms worse, especially long flights
- worse symptoms and outlook for other lung conditions, including COPD.
Getting an early diagnosis, and knowing the type of pulmonary hypertension you have, can lower your risk from complications.
Your doctor or specialist will make a pulmonary hypertension treatment plan for you, including any lifestyle changes. Following this plan can help your condition and lower your risk.
Children and pulmonary hypertension
Newborn babies, young children and teenagers can have pulmonary hypertension.
Pulmonary hypertension is less common in children than in adults. There are around 300 children in the UK living with pulmonary hypertension.
Treatments used for adults can work well for children too. As your child changes and grows, they may need different treatments. With the support of a specialist pulmonary hypertension team, and the right treatment, the outlook for children with pulmonary hypertension can be better than for adults.
Pulmonary Hypertension Association UK (PHA UK) has more information and support for parents of children who have been diagnosed with pulmonary hypertension, including a free guide, and interviews with parents and children living with pulmonary hypertension.
You may also want to join our Parent and Carer Support Network which provides support and a space for parents and carers of children with lung conditions to come together.

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