Hypertrophic cardiomyopathy (HCM)
What is hypertrophic cardiomyopathy?
Hypertrophic cardiomyopathy is a condition where the heart muscle becomes abnormally thickened (hypertrophied). This usually affects the left ventricle, which is the main pumping chamber of the heart.
Hypertrophic cardiomyopathy is an inherited condition that is estimated to affect between one in 200 and one in 500 people.
What are the symptoms of hypertrophic cardiomyopathy?
Symptoms of hypertrophic cardiomyopathy may include:
- chest pain, particularly during exercise
- shortness of breath, particularly during exercise
- lightheadedness or dizziness
- fainting
- heart palpitations
- irregular heart rhythm (arrhythmia)
- fatigue
- swelling in feet, ankles, legs, abdomen, or neck
Some people with hypertrophic cardiomyopathy may experience only minor symptoms, or no symptoms at all.
What causes hypertrophic cardiomyopathy?
Hypertrophic cardiomyopathy is an inherited condition, meaning it is usually passed down through families.
A parent with the gene mutation has a 50 percent chance of passing it on to their child. However, not everyone with the gene mutation will go on to develop an enlarged heart muscle, and those who do may have varying degrees of disease severity.
What is the difference between hypertrophic cardiomyopathy and obstructive hypertrophic cardiomyopathy?
There are two types of HCM:
- Obstructive HCM (HOCM) refers to muscle thickening that blocks (obstructs) blood flow
- Nonobstructive HCM refers to muscle thickening that does not block (obstruct) blood flow
How is hypertrophic cardiomyopathy diagnosed?
Your doctor will likely discuss any family history of hypertrophic cardiomyopathy. They may also perform some of the following tests:
- echocardiogram
- electrocardiogram (ECG)
- chest x-ray
- blood tests
- stress test
- genetic testing (other family members may be advised to be tested as well)
How is hypertrophic cardiomyopathy treated?
Treatment for hypertrophic cardiomyopathy aims to manage symptoms. This may include:
- medications - such as beta-blockers, calcium channel blockers, anti-arrhythmics, and blood thinners
- procedures - such as septal myectomy, septal ablation, implantable cardioverter defibrillator (ICD)
- management of other conditions - such as diabetes, high cholesterol etc
- lifestyle changes – avoiding strenuous activity when advised to do so, limiting alcohol consumption, eating a healthy diet and quitting smoking
How can hypertrophic cardiomyopathy be prevented?
As hypertrophic cardiomyopathy is a genetic condition, there is currently no way to prevent it. For those with hypertrophic cardiomyopathy in their family, genetic testing may be appropriate. Regular screening via echocardiogram may also be recommended for those with first degree relatives with the condition.
Hypertrophic cardiomyopathy patient stories
Read the stories of these amazing heart warriors who've experienced hypertrophic cardiomyopathy and complications in their heart disease battles.
Acknowledgement of Country
The Victor Chang Cardiac Research Institute acknowledges Traditional Owners of Country throughout Australia and recognises the continuing connection to lands, waters and communities. We pay our respect to Aboriginal and Torres Strait Islander cultures; and to Elders past and present.