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Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a genetically determined heart disease that involves thickening (hypertrophy) of the heart muscle, most commonly involving the interventricular septum. The septum is the heart muscle wall that separates the two ventricles (two lower pumping chambers of the heart).

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Heart Muscle Thickening

The term "cardiomyopathy" indicates that the increase in muscle thickness is related to a disease of the muscle itself and is not caused by other conditions that are known to make the heart muscle thicken because it is forced to work harder. The thickened heart muscle is also stiffer than normal and thus does not relax easily to fill with blood between each heartbeat.

  • HCM is the most common genetic disease of the heart (prevalence: 1 in 500).
  • HCM is the most common cause of sudden cardiac death in young people and athletes.
  • HCM is most commonly diagnosed in the second or third decade of life, but may be diagnosed at any age.

Outflow Tract Obstruction

In some patients, the muscle is thickened in a critical place that narrows the outflow passage through which blood is pumped out of the heart. This condition is called "outflow tract obstruction." This creates the murmur (abnormal extra sound made when the heart beats) that is heard in many, but not all, patients with HCM. The abnormally thickened heart muscle is composed of disorganized muscle cells and may also contain scar tissue. The abnormal muscle cells and scar tissue can cause abnormal heart rhythms.

Treatment Options for Hypertrophic Cardiomyopathy

The Center for Heart Failure offers cutting edge diagnostic testing as well as medical and surgical treatment options for patients with HCM. Robert O. Bonow, MD is a world-renowned cardiologist in the medical management of patients with HCM. Dr. Bonow is joined by fellow cardiologist Lubna Choudhury, MD who has extensive experience in the management of HCM. Patrick M. McCarthy, MD is an internationally known cardiac surgeon who performs cardiac surgical procedures for HCM, including septal myectomy (surgical removal of thickened septal tissue) and the Maze procedure, for patients who continue to experience severe symptoms with medical management. Drs. Bonow and McCarthy lead an expert team of surgeons, cardiologists, advance practice nurses, cardiac rehabilitation specialists, psychologists and social workers who contribute their expertise in the management of this disease.


For more information regarding HCM and available treatments, please contact the Bluhm Cardiovascular Institute at 1-866-662-8467 or request a first time appointment online.

In addition, the most credible source of information about HCM is the Hypertrophic Cardiomyopathy Association (HCMA). Please visit the HCMA Web site.

Last UpdateJuly 10, 2012