Hypertrophic Cardiomyopathy (HCM) affects an estimated 600,000 Americans each year—and claims the lives of roughly 6,000 of them—as the most common genetic heart defect and most frequent cause of cardiac sudden death in young people and athletes. The defect causes heart muscle to thicken and usually affects the muscle wall separating the two lower pumping chambers of the heart, an area known as the interventricular septum. One of the most frightening characteristics of this disease is that many patients have no symptoms. They lead normal, active lives, yet may succumb to sudden death as a first indication that the disease was even present.
“This can be a very frightening disease,” said Robert O. Bonow, MD, Northwestern Memorial’s chief of cardiology and co-director of the hospital’s Bluhm Cardiovascular Institute. “But thanks to today’s advances in the detection and treatment of HCM, it is now less concerning as more and more lives are being saved.”
World renowned for his treatment and medical management of patients with HCM, Dr. Bonow says knowing your family history is a best defense. “It is critical for individuals with a family history of the disease, or those who experience symptoms such as shortness of breath, chest pain or lightheadedness, to be evaluated by a physician who specializes in the testing and treatment of HCM. Many people dismiss cardiac symptoms in young people, which could be a fatal mistake.”
HCM is usually diagnosed during the late teens or early twenties as it most commonly develops in association with growth. Tests are usually performed when symptoms present or following the detection of a heart murmur. In addition, if a family member is discovered to have the disease, genetic testing can be done among parents, children and siblings. Diagnosis can be made through an echocardiogram, which is an ultrasound of the heart, or through an MRI which is more extensive testing to fully evaluate the amount and location of muscle thickening.
With HCM, the heart muscle thickness relates to the presence of disease within the muscle itself. This can be very problematic because when the heart muscle thickens it is forced to work harder. Because thickened heart muscle is also stiffer than normal, it does not relax easily to allow the heart to fill with blood between each heart beat. In some patients, the muscle thickening occurs in a critical place that narrows the outflow passage through which blood is pumped out of the heart; this creates an abnormal, extra sound (or murmur) that is made when the heart beats.
The treatment of HCM depends on the severity of muscle thickening, the presence or absence of a narrowing outflow passage, and the results of risk evaluation. Treatment options include:
The Bluhm Cardiovascular Institute’s Center for Heart Failure is one of nine specialty centers within the program. For the detection and management of HCM, the Center takes a multidisciplinary approach leveraging a team of experts including surgeons, cardiologists, advance practice nurses, cardiac rehabilitation specialists, psychologists and social workers. Their combined expertise offers cutting-edge diagnostic testing as well as medical and surgical treatment options. For more information about HCM and the Center for Heart Failure at the Bluhm Cardiovascular Institute, please visit www.nmh.org/heart.
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