What is a heart attack?

Coronary heart disease

Coronary heart disease (CHD) is the leading cause of heart attacks. CHD is a condition in which the coronary arteries (the major blood vessels that supply the heart with blood) become clogged with deposits of cholesterol. These deposits are called plaques.Before a heart attack, one of the plaques ruptures (bursts), causing a blood clot to form at the site of the rupture. The clot may block the supply of blood to the heart, triggering a heart attack.