Hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy is a thickening of the heart muscles (usually in the left ventricle) without any other underlying cause, resulting in an impairment of the function of the heart. It's one of the most common causes of sudden cardiac death of people of all ages, particularly young and athletic people. In fact, it is often asymptomatic under the patient dies. 
The thickening causes several functional issues in the heart, including disrupting the normal alignment of the cells of the muscle and the electrical signals that flow through the heart. Its most common underlying cause is a fault in one of nine genes that affect heart muscles. Exact figures are unknown, but it does affect 2-5 of every 1,000 people of all ages and ethnic groups.
It's difficult to diagnose as, if the patient is symptomatic, the symptoms are prosaic and non-distinctive such as shortness of breath, angina, palpitations, lightheadedness, fatigue, and fainting. Genetic tests are definitive, but are generally not a routine procedure. Cardiac catheterization is also useful in establishing a diagnosis.
Once diagnosed, the condition can be managed with medication, usually beta blockers to help alleviate the symptoms. In severe cases that do not respond to medication, surgery or a pacemaker may provide relief. Transplant is rare but may be necessary in some cases.
Hypertrophic cardiomyopathy at Wikipedia
Category:Cardiology