A patient of myocardial Infarction dies after first few hours of infarction due to:

Myocardial infarction occurs due to the formation of occlusive thrombus at the site of rupture of an atheromatous plaque in a coronary artery. Sudden death from ventricular fibrillation or asystole, may occur immediately and many deaths occur within the first hour. Death in those who survive the first few hours of infarction occurs due to cardiac failure.