MedlinePlus Medical Encyclopedia: Acute MI

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Acute MI

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.

Update Date: 2/20/2007

Updated by: Updated by A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously reviewed by Alan Berger, MD, Assistant Professor, Divisions of Cardiology and Epidemiology, University of Minnesota, Minneapolis, MN. Review provided byVeriMed Healthcare Network. (2006)

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