The inciting event for a heart attack is the rupture of an “unstable” plaque in one of the arteries feeding blood with oxygen and nutrients to the heart muscle. Once this happens, the tissues of the arterial wall are exposed to the circulating blood and its components, one of which is platelets. The tissues contain collagen, which are potent activators of the clotting mechanism. One of these, collagen, activates platelets, which stick to the arterial wall tissues, stimulate other platelets to join in the action, and develop a clot at the site where the “unstable” plaque ruptured. The degree to which the artery is clogged with clot determines the extent of the heart attack.
