DCM – Dilated Cardiomyopathy

What is dilated cardiomyopathy?

Dilated Cardiomyopathy (DCM) is a condition which affects the heart muscle and can lead to the heart chambers (particularly the left ventricle which is the main pumping chamber in the heart) becoming enlarged and not pumping effectively. Around 25-35% of patients with a DCM will have an inherited form (familial) but other causes include viral infections, high blood pressure, excessive alcohol consumption, pregnancy and certain medicines (particularly those used for chemotherapy).

In familial DCM the condition usually affects a first degree family member such as parent, child or sibling in 50% of cases. Therefore if someone is found to have an inherited dilated cardiomyopathy doctors would usually recommend their family members are tested. There are many genes which are known to cause DCM but the most common are Lamin A/C mutations and occasionally doctors might suggest a patient has genetic testing looking for these genes.


The symptoms can be quite variable; some patients may have no symptoms whereas others may have quite severe symptoms.

Symptoms include:

• Shortness of breath
• Ankle swelling
• Tiredness
• Palpitations (a sensation of the heart beating fast or abnormally)

How is dilated cardiomyopathy diagnosed?

It is likely that the doctors will perform an electrocardiogram or ECG which is tracing of the electrical activity of the heart. They will also perform an echocardiogram (an ultrasound of the heart) which gives information about the heart size and how well it pumps. If these tests have shown that you have a DCM, you may go on to have more specialist tests. These include a 24-hour ECG monitor to look for abnormal heart rhythms, an exercise test and occasionally a cardiac MRI which gives more in-depth information about the heart structure and function. Routine screening of family members to assess for the condition usually includes an ECG and echocardiogram.

What treatment is available?

• Most patients with DCM will be put onto a beta-blocker tablet and another drug known as an ACE-inhibitor. If the symptoms are quite severe other tablets such as diuretics (which help get rid of fluid in the body) are added.

• Rarely some patients require a pacemaker to help regulate the heart beat or an Implantable cardioverter-defibrillator or ICD which is used to protect patients from a cardiac arrest who are at risk of life-threatening abnormal heart rhythms.