Pulmonary vascular disorders explained

The lungs receive blood from the right side of the heart through the pulmonary arteries. These vessels are low-pressure and normally stretch easily to let blood through. Pulmonary vascular disorders are conditions in which that circuit becomes blocked, stiffened, narrowed or overloaded.

This page covers the two groups most patients meet, with sources: pulmonary hypertension in its five groups, and pulmonary embolism. Related conditions such as congenital narrowing of the pulmonary valve, interstitial lung disease and heart failure have their own pages.

The NHS describes pulmonary hypertension as high blood pressure in the blood vessels that supply the lungs. The walls of the pulmonary arteries become thick and stiff and cannot expand as well, so the right side of the heart has to work harder and may gradually weaken, leading to heart failure. It can affect people of all ages and is more common in people with another heart or lung condition.

Symptoms listed by the NHS are shortness of breath, tiredness, feeling faint or dizzy, chest pain, palpitations and swelling in the legs, ankles, feet or abdomen. They often worsen with exercise. Asthma + Lung UK adds that people may look well and notice symptoms only with everyday activities such as climbing stairs.

Pulmonary hypertension has several causes, grouped so that doctors can choose the right treatment. PHA UK and Asthma + Lung UK describe five groups. Identifying the group is a core step in diagnosis, because treatment for one group may not suit another.

A pulmonary embolism is a blood clot blocking a blood vessel in the lungs. The NHS says symptoms include difficulty breathing that comes on suddenly, chest pain that is worse when you breathe in and coughing up blood, sometimes with pain, redness and swelling in one calf from a deep vein thrombosis. It often happens when part of a clot dislodges from a leg and travels to the lungs.

Call 999 or go to A&E for severe difficulty breathing, pain in the chest or upper back, a very fast heartbeat or if someone has passed out. For sudden breathing difficulty or coughing up blood without those features, ask for an urgent GP appointment or contact NHS 111. Do not drive yourself to A&E.

Anticoagulant injections are started in hospital, often before test results, and the NHS says you continue them for at least 5 days and take anticoagulant tablets for at least 3 months. The NHS says a full recovery is expected if it is spotted and treated early.

Pulmonary hypertension can take time to diagnose because its symptoms resemble many other heart and lung conditions, according to the NHS. Tests include an echocardiogram and right heart catheterisation, where a thin flexible tube is placed in the pulmonary artery. PHA UK lists further tests such as lung function tests, CT scanning, ventilation-perfusion scanning and walk tests.

Asthma + Lung UK advises speaking to your GP if you are worried about breathlessness on activity or marked tiredness, as the GP can check for other causes and refer you. It stresses that the sooner you are referred, the sooner you can be diagnosed and start treatment. For suspected pulmonary embolism, the NHS says a GP will send you to hospital for tests and treatment.

The NHS says pulmonary hypertension cannot be cured but treatment can reduce symptoms, and that if another condition is causing it, that condition should be treated first. Treatments may include anticoagulants, diuretics for fluid, medicines to widen blood vessels and home oxygen if blood oxygen is low. PHA UK also lists oral, intravenous and subcutaneous treatments and surgical options, with care at specialist centres.

Asthma + Lung UK says risks from pulmonary hypertension include heart failure, complications with surgery and anaesthetic, complications in pregnancy and birth, and worse symptoms on long flights. Early diagnosis and knowing your type can lower the risk of complications. PHA UK classifies severity using WHO functional classes based on how much activity brings on symptoms.

For clot prevention the NHS advises hospital teams to take steps to prevent deep vein thrombosis for inpatients, and notes risk rises with flights over 4 hours. Moving regularly, drinking water, loose clothing and flexing the legs help on long journeys.

Asthma + Lung UK says newborn babies, young children and teenagers can have pulmonary hypertension, although it is less common than in adults, with around 300 children in the UK living with it. Treatments used for adults can work well for children, and the charity says that as a child grows they may need different treatments.

With a specialist team and the right treatment, the outlook for children can be better than for adults, the charity says. PHA UK has information and support for families.