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Highland Hospital / Departments - Centers / Cardiology / Conditions We Treat / Hypertrophic Obstructive Cardiomyopathy

Hypertrophic Obstructive Cardiomyopathy (HOCM)

Hocm VideoHypertrophic Obstructive Cardiomyopathy (HOCM) is a cardiac abnormality which leads to the muscle in the wall of the heart growing and thickening to the point that it blocks blood flow exiting the heart.

  • During periods of strenuous exertion and/or dehydration, the degree of obstruction to blood flow progresses and can prevent the heart from pumping blood to the rest of the body, including the heart itself. This can then cause heart rhythm abnormalities, cardiac arrest (the heart stops) and death. HOCM is the leading cause of sudden cardiac death in athletes.


Normal HeartHypertrophic Cardiomyopathy

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  • Often, this condition is asymptomatic until someone passes out or suffers cardiac arrest, unfortunately.
  • If a young person is having dizziness, chest pain or passes out during exercise, this condition should be considered.

Diagnostic Tests


  • Sometimes patients will be placed on drugs such as beta-blockers (metoprolol, atenolol, etc) to prevent heart rhythm abnormalities and to relax the heart.
  • Patients may require surgery or a cardiac catheterization procedure (angiogram) to remove the excess muscle tissue in the heart.
  • This problem may require implantation of a defibrillator to prevent life-threatening arrhythmias.

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