Hypertrophic cardiomyopathy can affect each individual differently with no uniquely diagnostic symptoms; the symptoms of HCM are generally the same as those of coronary artery disease or heart failure. Many people never develop symptoms; others are profoundly affected by the symptoms. Often the symptoms appear later in one's life. The severity of those symptoms varies widely, but for most people, the disease doesn't affect the quality or length of their lives.
Usually, the symptoms come and go. They may initially be attributed to other more common conditions. The symptoms may vary depending upon a variety of factors, such as the temperature of the room, the timing and salt content of the last meal, body position, and exertion.
One important but rare symptom, occurring in 1 percent of the people with HCM, is sudden death. Sudden death frequently occurs in otherwise healthy individuals during athletic training or exertion, and it may be the only symptom experienced by an individual who has not yet been diagnosed with hypertrophic cardiomyopathy.
There are four primary symptoms of HCM:
- Dyspnea, or shortness of breath, is the most common symptom of HCM and can be associated with fatigue. For most people, dyspnea does not limit lifestyle or exercise capacity; however, severe shortness of breath may occur while lying down in a minority of people with HCM.
- Angina, or chest pain or pressure, is also frequently reported by people with HCM, usually right after exertion. Chest pain results when the oxygen demands of the overgrown heart muscle are not met or obstruction within the heart limits the circulation of blood and oxygen to the body, including the heart.
- Syncope, or fainting, may occur. The heart's less efficient pumping and changes in its rhythm both contribute to lightheadedness, dizziness, and syncope. Usually, these episodes occur during or right after exercise when the demand on the heart muscle increases, causing it to contract harder and faster, which can decrease blood flow out of the heart to the body, including the brain.
- Palpitations, or changes in the rhythm of heart, may feel like a rapid heartbeat, a skipped or extra heartbeat, or just an uncomfortable awareness of one's heartbeat. Palpitations can be associated with sweating or lightheadedness.
Hypertrophic cardiomyopathy is a complex disease causing a variety of highly individualized symptoms that initially may be attributed to other diseases. The most common misdiagnoses are:
- Exercise-induced asthma. Because the common symptom of HCM, shortness of breath, may happen with exertion, it is not uncommon for individuals to be diagnosed with exercise-induced asthma. This is especially true for young, otherwise healthy individuals whose first symptom is shortness of breath during or following exertion.
- Mitral valve prolapse. The heart murmur caused by regurgitating blood back through the mitral valve in patients with HCM sounds similar to that caused by the regurgitation resulting from mitral valve prolapse, a condition associated with a structural defect in the mitral valve. Mitral valve prolapse can also cause shortness of breath as well as dizziness, fatigue, and palpitations.
- Anxiety and/or depression. In addition, the palpitations, shortness of breath, and chest pain may be attributed to anxiety attacks, panic attacks, or even some forms of depression.
Last reviewed on 2/11/2009