Cardiomyopathy may be inherited and run in families, and can affect children and younger people. Some people develop cardiomyopathy due to another condition or risk factor, but in some cases the cause is unknown.

The way that the heart is affected depends on the type of cardiomyopathy, and the chambers of the heart may become:

• stretched, thin and weak
• thick, stiff and fibrous

The three main types of cardiomyopathy are:

• hypertrophic cardiomyopathy
• dilated cardiomyopathy
• arrhythmogenic right ventricular cardiomyopathy (ARVC)

A rarer, fourth type is Takotsubo cardiomyopathy, or ‘broken heart’ syndrome, which is usually temporary and reversible. It is triggered by severe emotional or physical stress, and is thought to be caused by a surge in stress hormones, particularly adrenaline.

Although some people have cardiomyopathy without any symptoms, others might experience symptoms such as:

• breathlessness
• swelling of the abdomen, legs and/or feet
• feeling lightheaded or faint
• abnormal heart rhythms
• chest pain

There is no cure for cardiomyopathy, but early diagnosis is important, and treatments can help to control symptoms and prevent complications. Some people may need to take medicines to decrease the heart rate, or anticoagulants to prevent the formation of blood clots. Sometimes a pacemaker is implanted to control the heart rate or an implantable cardioverter defibrillator (ICD) to shock the heart if it goes into a dangerous rhythm. In rare cases, heart surgery or a heart transplant may be needed.