Arrhythmogenic Cardiomyopathy


What is Arrhythmogenic cardiomyopathy (ACM)?

  • ACM is a genetic heart muscle condition which affects the right ventricle, left ventricle, or both.
  • ACM has been referred to in the past as Arrhythmogenic Right Ventricular Cardiomyopathy as it was initially thought that it exclusively affected this pumping chamber of the heart.


What are the symptoms of ACM?

Some of the symptoms are related to the electrical activity of the heart as well as the structure of the heart and how well it pumps. 

Symptoms can include the following:

  • Palpitations (or 'arrhythmias') - feeling your heart beating too fast, too hard or like it is ‘fluttering’ – this is caused by abnormal heart rhythms. 
  • Light-headedness and fainting (loss of consciousness or 'syncope') – reduced oxygen levels or blood flow to the brain can be caused by abnormal heart rhythms. 
  • Swollen legs, ankles and tummy – as the heart isn’t pumping effectively.
  • Breathlessness – as fluid builds up around the lungs.
How is ACM diagnosed?

ACM can be difficult to diagnose as the changes in the heart can be subtle and the fat deposits can be hard to see. The heart chambers can become enlarged, meaning that it is sometimes misdiagnosed as dilated cardiomyopathy.

  • Medical history – to look at symptoms and whether other family members have this condition (as it can be genetic).
  • Physical exam – to see what physical symptoms, if any, are happening.
  • ECG (electrocardiogram) – this looks at the electrical activity of the heart and whether abnormal heart rhythms are happening.
How is ACM treated and managed?

Although there is no cure for ACM, treatments are used to reduce and control symptoms, and reduce the risk of complications. Treatment focuses on improving the pumping of the heart and controlling abnormal heart rhythms. 

Treatments include medication, implantable devices, surgery, exercise restriction and lifestyle management

Heart with ACM


Support for Arryhythmogenic Cardiomyopathy (ACM)

We have an online support group for people diagnosed with ACM and their families. This group is hosted by Cardiomyopathy UK Specialist Nurse Jayne.

Find out more