Heart attack is a disease of the heart. The coronary arteries supply blood and oxygen to the heart. When the coronary artery closes for any reason, the flow of blood and oxygen to the heart stops. The disease that results from this is called heart attack. Stroke, on the other hand , is a disease of the brain. If for some reason the blood vessels of the brain rupture and excess blood accumulates or the blood flow to the brain is obstructed , that condition is called stroke.