How can a heart attack happen?

Heart attack: The usual event is a plaque in a coronary artery ruptures and a clot forms on it which then blocks off the artery. The downstream muscle becomes ischemic then dies. If you get to the hospital in time go get the vessel opened up, some muscle can be saved.

Gradual blockage: Avoid by: good personal habits no smoking regular exercize monitor blood pressure check cholesterol and general physical features know your family history the atherosclerosis is established over time and deposits and gets to the critical stage and clots, or the plaque disrupts like a trap door causing acute blockage and threatened or damaged heart muscle.