Heart disease is any disorder that affects the heart's ability to function normally. The most common cause of heart disease is narrowing or blockage of the coronary arteries, which supply blood to the heart itself. This happens slowly over time. (See coronary artery disease.)

Some heart diseases can be present at birth (congenital heart diseases).

Other causes include the following:

• Abnormal function of the heart valves
• Abnormal electrical rhythm of the heart
• Weakening of the heart's pumping function caused by infection or toxins

Various forms of heart disease include:

• Alcoholic cardiomyopathy
• Aortic regurgitation
• Aortic stenosis
• Arrhythmias
• Cardiogenic shock
• Congenital heart disease
• Coronary artery disease (CAD)
• Dilated cardiomyopathy
• Endocarditis
• Heart attack (myocardial infarction)
• Heart failure
• Heart tumor
• Hypertrophic cardiomyopathy
• Idiopathic cardiomyopathy
• Ischemic cardiomyopathy
• Mitral regurgitation; acute
• Mitral regurgitation; chronic
• Mitral stenosis
• Mitral valve prolapse
• Peripartum cardiomyopathy
• Pulmonary stenosis
• Stable angina
• Unstable angina
• Tricuspid regurgitation

See also chest pain.