Sometimes the first symptom of the heart muscle disease hypertrophic cardiomyopathy (HCM) is sudden cardiac death, and some of its most tragic victims are teenagers and young adults. HCM is a complex disease and it affects vastly different groups of people. HCM prevention and treatment save lives, but only if screening identifies those at risk. Some experts recommend screening for all children and teenagers before they participate in competitive sports.
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People with hypertrophic cardiomyopathy have abnormally thick heart muscle tissue. The disease most often affects the wall (septum) that divides the lower chambers (ventricles) of the heart.
Causes of HCM:
“Pay attention to any episodes of fainting, unusual shortness of breath or light-headedness that occur with or without exertion.”
- Genetic origins
- Heart valve disease or defects
- Years of chronic high blood pressure
Obstructive hypertrophic cardiomyopathy
When thickened heart tissue obstructs blood flow from the heart, people can experience shortness of breath and dizziness.
There are safe and effective surgical options for people who suffer from obstructive hypertrophic cardiomyopathy. To relieve symptoms, surgeons performing septal myectomy cut away excess tissue causing the blockage.
Sudden cardiac death
Sudden cardiac death can occur when the thickened septum interferes with the electrical signals that regulate heartbeat. When this happens, the heart quivers ineffectively, beating fast and erratically (arrhythmia), and blood circulation stops suddenly.
A patient suffering this deadly type of ventricular arrhythmia will lose consciousness in as little as 30 seconds and, without immediate intervention such as a shock sent from an external defibrillator to reset the heart, death follows.
Survival and prevention
Despite increased public awareness about CPR and availability of external defibrillator devices in public places, the prognosis for people suffering sudden cardiac arrest remains poor. Ninety-five percent of people who suffer cardiac arrest outside a hospital die.
Most people with HCM are not at risk for sudden cardiac death, but it’s important to identify those who are at higher risk:
- Patients who have a family history of sudden cardiac death
- Young patients who have had several episodes of syncope (fainting)
- Patients who experience an abnormal blood pressure response with exercise
- Patients who have a history of arrhythmia with a fast heart rate
- Patients with severe symptoms and poor heart function
The best solution to this deadly problem is prevention. Implantable cardioverter defibrillators (ICDs) can prevent sudden death with a shock sent to restart a flailing heart.
Electrocardiograms can identify potential problems that could lead to sudden cardiac arrest.
Because HCM can strike young people suddenly, Harry Lever, MD, medical director of Cleveland Clinic’s Hypertrophic Cardiomyopathy Clinic, urges vigilance on the part of parents, coaches and teachers. “Screening is advisable for any young person who has a strong family history of sudden cardiac arrest or heart valve disorders, or who has a heart murmur. Pay attention to any episodes of fainting, unusual shortness of breath or light-headedness that occur with or without exertion. Finally, be aware that young people, particularly athletes, might feel pressure to ‘train through’ problems. But, there is no such thing as toughing it out when hypertrophic cardiomyopathy initiates cardiac arrest,” Dr. Lever says.
He adds that this information is important for people of all ages. Although the risk decreases with age, there are still incidences of sudden cardiac death in older people.