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:
Hypertrophic obstructive cardiomyopathy (HOCM)—the muscle between the two valves of the heart becomes so enlarged that it obstructs the blood flow in the heart
Non-obstructive hypertrophic cardiomyopathy—non-obstructive form, the enlarged muscle is not large enough to block blood flow
Normal Heart and Heart with Hypertrophic Cardiomyopathy
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:
Having a family member with HCM
Being over age 60 and having hypertension
Fainting, particularly during exercise
Lightheadedness, particularly following exercise
Shortness of breath or difficulty breathing
Tiring easily during exercise or activity
Shortness of breath when lying down
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
Images may be taken of your bodily structures. This can be done with:
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.
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