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41 Old myocardial infarct

Myocardial infarction
Age/sex: 81-year-old male
Size: 17.5 x 18.0 x 8.0 cm
The left ventricle has been opened to show a normal aortic valve (A) and posterior leaflet of the mitral valve (M). A large area of thickened white (W) endocardium overlies an infarct of the inter-ventricular septum. Short arrows show pale fibrous tissue (scar) in the myocardium of the adjacent anterior ventricular wall. A depressed area filled with thrombus (long arrow) represents early aneurysm formation.


Myocardial infarction

Tissue death that occurs because of a lack of blood flow (ischemia) is called infarction. Infarcts can occur in many organs but are particularly common in the heart and brain. In the first few days following infarction, the dead tissue typically appears reddish or yellowish (from either admixed blood or neutrophils, respectively). After several months, healing (scarring) occurs resulting in a grey or white appearance.

Most myocardial infarcts are caused by a sudden decrease in blood flow through a coronary artery caused by thrombus (blood clot) that forms next to a focus of atherosclerosis. In some cases, the affected individual dies rapidly because of an irregular heart beat (arrhythmia) or inability of the remaining normal heart muscle to pump enough blood to the body. In others, the amount of tissue damage is not enough to cause death and the individual may complain of chest pain or pressure, shortness of breath, and/or light-headedness – all symptoms of a heart attack.

Below: An illustration depicting a recent myocardial infarct in the inferior left ventricular wall (dark red).

Source: Lynch, P. (2006). Heart inferior wall infarct. Wikimedia Commons.

An illustration depicting a recent myocardial infarct in the inferior left ventricle (dark red).

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