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Acute MI

Acute MI

Overview

A heart attack or acute myocardial infarction (MI) occurs when one of the arteries that supplies the heart muscle becomes blocked. Blockage may be caused by spasm of the artery or by atherosclerosis with acute clot formation. The blockage results in damaged tissue and a permanent loss of contraction of this portion of the heart muscle.

Review Date 3/31/2024

Updated by: Larry A. Weinrauch MD, Assistant Professor of Medicine, Harvard Medical School, Cardiovascular Disease and Clinical Outcomes Research, Watertown, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.