Symptoms:

• Chest pain
• Dizziness
• Fainting, especially during exercise
• Heart failure (in some patients)
• High blood pressure (hypertension)
• Light-headedness, especially with or after activity or exercise
• Sensation of feeling the heart beat (palpitations)
• Shortness of breath

Other symptoms that may occur are:

• Fatigue, reduced activity tolerance
• Shortness of breath when lying down

Some patients have no symptoms. They may not even realize they have the condition until it is found during a routine medical exam.

The first symptom of hypertrophic cardiomyopathy among many young patients is sudden collapse and possible death. This is caused by very abnormal heart rhythms (arrhythmias), or from the blockage of blood leaving the heart to the rest of the body.

Hypertrophic cardiomyopathy is a major cause of death in young athletes who seem completely healthy but die during heavy exercise. However, certain normal changes in athletes' hearts can confuse the diagnosis.

Signs and tests:

The health care provider will perform a physical exam and listen to the heart and lungs with a stethoscope. Listening with a stethoscope may reveal abnormal heart sounds or a murmur. These sounds may change with different body positions.

The pulse in your arms and neck will also be checked. The doctor may feel an abnormal heartbeat in the chest.

Tests used to diagnose heart muscle thickness, problems with blood flow, or leaky heart valves (mitral valve regurgitation) may include:

• 24-hour Holter monitor (heart monitor)
• Cardiac catheterization
• Chest x-ray
• ECG
• Echocardiography (the most common test) with Doppler ultrasound
• MRI of the heart
• Transesophageal echocardiogram (TEE)

Not all of these tests are useful for evaluating all of these conditions.

Blood tests may be done to rule out other possible diseases.

If you are diagnosed with hypertrophic cardiomyopathy, your health care provider may recommend that your close blood relatives (family members) be screened for the condition.