Types of pulmonary hypertension

Pulmonary hypertension (PH) is a rare heart and lung condition where the pressure in the pulmonary arteries (the blood vessels that carry blood from heart to the lungs), is higher than normal. 

It's important to diagnose, treat and manage pulmonary hypertension correctly because it is a potentially life-threatening condition. PH can occur with or without an identifiable or known cause.

Sometimes referred to as 'high blood pressure in the lungs,' it's important to know that PH is very different to the kind of high blood pressure we measure using your arm. PH is a rare condition that affects approximately one in 20,000 people in the UK, unlike raised blood pressure (systemic hypertension), which is more common.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a type of PH which affects the smaller branches of the pulmonary arteries. When they are affected, it can cause high pressure in these blood vessels. Being put into this group will depend on your baseline tests. 

Chronic thromboembolic disease (CTEPH)

This is a subgroup of pulmonary hypertension brought on by the presence of chronic blood clots. 

PH and the body

To understand PH, it's useful to have an understanding of the normal flow of blood through the heart and lungs:

The right ventricle

This is one of the big pumping chambers of the heart. It pumps blood that has been circulated around the body through the pulmonary arteries and into the lungs. In the lungs, the blood picks up oxygen and flows back to the left side of the heart, where it is pumped around the body to begin the cycle again. 

The pulmonary arteries

If the pressure in the pulmonary arteries becomes higher than normal, the walls of the blood vessels may become thicker and less flexible. 

Over a period of time the right ventricle also becomes thick and stiff and has to work harder to pump blood through the lungs and the heart. This means the heart eventually works less effectively. This can take several years. 

Common symptoms

The most common symptoms of PF are shortness of breath and fatigue. Less common symptoms include:

• shortness of breath
• excessive tiredness/fatigue
• chest pains
• palpitations (a racing, thumping, or fluttering feeling in your chest)
• dizziness
• fainting or near fainting episodes, known as syncope

These symptoms can occur at rest or, more often, during periods of physical exertion, and have an impact on a person's day-to-day life. 

Causes

There are many different types of PH and sometimes the cause is unknown, which is called idiopathic pulmonary arterial hypertension (IPAH). 

More commonly, PH is linked to other diseases, such as:

• heart diseases you were born with (called congenital heart disease)
• connective tissue disease such as systemic sclerosis
• thromboembolic disease (blood clots in the lungs)
• human immuno-deficiency virus (HIV)

In some cases, PH can also be inherited. 

Diagnosis

If PH is suspected, you will be referred to one of seven designated specialist centres in the UK - we are one of them. Information is shared between these centres and we investigate patients for PH. Tests include:

• blood tests
• cardiopulmonary exercise test (CPET) (this asseses how your lungs, heart and muscles react when you exercise on a bike)
• chest x-ray
• echocardiogram
• CT scan
• MRI scan
• lung function test
• ECG
• walk test (a test to see how far you can walk in six minutes)
• right-heart catheter study (this measures blood pressures within your heart and lungs)
• V/Qscan
• Sleep study

Some of these tests may already have been performed at your local hospital and will only be repeated if necessary.

We sometimes ask patients to also see Dr James Hull, who runs the unexplained breathlessness service, and performs detailed supervised exercise tests in the Fulham Road wing of Royal Brompton hospital. He has a team of experts who specialise in patients who have breathlessness. 

A confirmed diagnosis of PH is usually made by carrying out a test called a right heart catheterisation, also known as cardiac catheterisation. Following that, you will be introduced to one of our pulmonary hypertension specialist nurses. 

The results of the tests will be explained to you and there may also be other procedures, depending on your situation. 

Available treatments

There is no cure for most types of PH but we can provide treatment which helps to manage your condition and help reduce your symptoms. Most patients who need treatment are started on tablets, but some people will start more complicated treatments due to the nature and severity of their condition. 

The treatments you have depend on your type of PH. If it's caused by another disease, then that must be treated also. 

Depending onthe cause of PH, you may have conventional therapy, such as:

• oxygen
• warfarin (blood-thinning medication)
• diuretics (water tablets)

But you may start on more specific therapies, such as:

• Sildenafil
• Tadalafil
• Bosentan
• Ambrisentan
• inhaled prostacyclin therapy (iloprost)
• intravenous prostacyclin therapy (Epoprostenol)

These disease-specific treatments, called pulmonary vasodilators, help to relax the arteries in the lungs. This allows blood to flow through the blood vessels more easily and reduces the blood pressure in your lungs. These treatments will be discussed with you in more detail during your consultation. 

In some cases of PH, disease-specific therapies may not be suitable for you to take. If this is the case, the reasons for this will be discussed with you, too. 

Treatment for PAH

If you have been diagnosed with PAH, your treatment will be:

• supported by the latest scientific evidence
• available for routine use on the NHS to treat pulmonary hypertension
• dependent on your local primary care trust agreeing to fund this therapy

Chronic thromboembolic disease (CTEPH)

If you have been diagnosed with CTEPH, you may be offered surgery to remove the blood clots. This procedure is called a pulmonary endarterctomy (PEA) and you would be referred to Papworth hospital in Cambridge. The staff at Papworth would find out more about you and decide whether this treatment is right for you. 

Find out more about our PH service.