Hypertrophic cardiomyopathy (HCM) is a form of cardiomyopathy. This is a condition in which the heart muscle thickens due to genetic problems with the muscle’s structure. As the muscle thickens, it must work harder to pump blood, which strains the heart muscle. Sometimes, the thickened muscle gets in the way of the blood leaving the heart and causes a blockage. This blockage can cause the nearby heart valve, called the mitral valve, to become leaky. HCM can cause uneven muscle growth which can cause the heart to pump in a disorganized way. Rarely, it can cause abnormal heart rhythms that can even be fatal.
There are two types of hypertrophic cardiomyopathy:
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Causes of HCM include:
In people over age 60, HCM is likely to be caused by or related to high blood pressure.
HCM is usually most severe when it occurs in yournger people, but it can occur at any age.
Other factors that may increase your chances of HCM include:
These symptoms can be caused by some of the side effects of the condition, including heart arrhythmias. The blocked or reduced blood flow is usually the cause of symptoms like lightheadedness, fainting, and difficulty breathing.
You will be asked about your symptoms and medical history. A physical exam will be done.
Your bodily fluids may be tested. This can be done with blood tests.
Your body's response to exercise may be tested. This can be done with a stress test.
Images may be taken of your bodily structures. This can be done with:
Your heart activity may be monitored. This can be done with a portable ECG.
Many individuals with HCM live a normal, healthy life with few symptoms. However, HCM does increase the risk of sudden death.
Treatment focuses on controlling symptoms and preventing complications. Talk with your doctor about the best treatment plan for you. Treatment may include:
Medications may be used to help maintain proper and regular heart function. These may include:
The thickened portion of the heart muscle is cut and removed. This may be needed if you have severely blocked blood flow from the heart.
If the mitral valve is leaking, surgery may also be done to repair or replace the mitral valve.
Alcohol is injected into the arteries of the thickened portion of the heart. This helps to reduce the blockage in the heart and improve blood flow out of the heart.
This ICD is implanted if you are at increased risk for sudden death.
To help reduce your chances of HCM:
American Heart Association
Canadian Cardiovascular Society
Heart and Stroke Foundation of Canada
Cardiomyopathy in adults. American Heart Association website. Available at: http://www.heart.org/HEARTORG/Conditions/More/Cardiomyopathy/Cardiomyopathy_UCM_444459_SubHomePage.jsp. Accessed September 15, 2017.
Explore cardiomyopathy. National Heart, Lung, and Blood Institute website. Available at: https://www.nhlbi.nih.gov/health/health-topics/topics/cm. Updated June 22, 2016. Accessed September 15, 2017.
Hypertrophic cardiomyopathy. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T115426/Hypertrophic-cardiomyopathy. Updated May 12, 2017. Accessed September 15, 2017.
What is HCM? St. Luke's Roosevelt Hospital Center website. Available at: http://www.hcmny.org/whatis/index.html. Accessed September 15, 2017.
Last reviewed September 2018 by EBSCO Medical Review Board Michael J. Fucci, DO, FACC Last Updated: 9/16/2016