Restrictive cardiomyopathy: a rare stiff-heart condition, symptoms and care

Cardiomyopathy is a general term for diseases of the heart muscle, where the walls of the heart chambers have become stretched, thickened or stiff, which affects the heart's ability to pump blood around the body. The NHS says most types are inherited and that it can also be caused by other conditions, or for some people the cause is unknown. It can affect people of all ages.

The NHS describes four main types in addition to broken heart syndrome: dilated, hypertrophic, restrictive and arrhythmogenic. In restrictive cardiomyopathy the walls of the main heart chambers become stiff and rigid and cannot relax properly after contracting. The heart therefore cannot fill up properly with blood, which reduces blood flow from the heart and can lead to symptoms of heart failure and heart rhythm problems.

This differs from dilated cardiomyopathy, where the walls become stretched and thin, and from hypertrophic cardiomyopathy, where the heart muscle cells enlarge and the walls thicken. In the restrictive form the main problem is stiffness that prevents filling rather than a failure to squeeze.

According to the NHS, restrictive cardiomyopathy can lead to symptoms of heart failure, such as breathlessness, tiredness and ankle swelling, as well as heart rhythm problems. Heart failure more generally typically causes shortness of breath, extreme tiredness and ankle swelling, according to the NHS description under dilated cardiomyopathy.

The NHS describes dizziness, chest pain, shortness of breath and temporary loss of consciousness as features of hypertrophic cardiomyopathy. Chest pain that starts suddenly, or comes with difficulty breathing or a fast heartbeat, should be treated as an emergency: the NHS advises calling 999 for chest pain with those features.

• Breathlessness, especially on exertion.

• Tiredness and low energy.

• Swollen ankles, legs or tummy.

• Palpitations or irregular heartbeat.

• Dizziness or fainting, which needs urgent assessment.

The NHS says in many cases of restrictive cardiomyopathy the cause is unknown, although sometimes it can be inherited. Because it can be inherited, the NHS says people with an inherited type of cardiomyopathy may be advised to have a genetic test to identify the faulty gene, so that relatives can be tested for the same mutation and, if they have it, monitored and managed early.

Cardiomyopathy UK lists related disorders such as cardiac amyloidosis, myocarditis and haemochromatosis on its information pages. The NHS says some types of cardiomyopathy have specific treatments, which is why finding the cause matters.

The NHS says some cases of cardiomyopathy can be diagnosed after heart scans and tests such as an electrocardiogram (ECG), an echocardiogram, an MRI scan, a heart rhythm monitor (24 or 48-hour ECG monitor) and exercise tests, and that a detailed family tree drawn by specialists may be required.

These tests show the thickness and movement of the heart walls and how well the chambers fill. If an inherited type is suspected, genetic testing and testing of close relatives may follow.

The NHS says there is usually no cure for cardiomyopathy, but the treatments can be effective at controlling symptoms and preventing complications. Some types have specific treatments, and early diagnosis is very important. Not everyone needs treatment, and some people with a mild form control it with a few lifestyle changes.

General lifestyle advice from the NHS is to eat a healthy diet and do gentle exercise, quit smoking, lose weight if overweight, avoid or reduce alcohol, get plenty of sleep, manage stress and make sure any underlying condition such as diabetes is well controlled. Medicines may be needed to control blood pressure, correct an abnormal heart rhythm, remove excess fluid or prevent blood clots. Those with heart rhythm problems may need arrhythmia ablation or a device such as a pacemaker or an implantable cardioverter defibrillator, and as a last resort a heart transplant may be necessary.

The NHS says people with some types of cardiomyopathy need regular appointments so the condition can be monitored. Cardiomyopathy UK, the specialist charity, provides information on types, treatments, genetics, lifestyle and exercise, emotional wellbeing, benefits, driving, returning to work, and has a nurse helpline and support groups.

Because restrictive cardiomyopathy is rare, many people have contact with a specialist cardiomyopathy service, and children and families may also have paediatric cardiology and genetics input.

On the NHS, suspected cardiomyopathy is investigated through cardiology with echocardiography and MRI, and inherited forms may be referred to inherited cardiac conditions services for genetic testing and family screening.

Private cardiology can offer faster imaging, but because the condition is rare and management is specialised, care is often shared with NHS specialist centres. Ask which team will coordinate long-term monitoring and who to contact if symptoms change.