Hypertrophic cardiomyopathy (HCM) is a disease in which the walls of the heart muscle become abnormally thick. When the walls of the heart are thick it makes it difficult to pump blood. HCM can affect men and women of any age. HCM often goes undiagnosed because people often have few symptoms. Some may experience symptoms such as shortness of breath, chest pain, fainting, dizziness, fatigue, heart murmur or sensation of a racing heart beat. A physician can typically diagnose HCM using a heart function test called an echocardiogram. Additional tests, such as a treadmill stress test, may be needed. Medication and certain medical procedures can help manage symptoms and prevent sudden cardiac death. People with HCM often lead normal lives with no significant problems.