Effects of heparin treatment on collateral development and regional myocardial function in acute myocardial infarction

Myocardial infarction (MI, heart attack) is the deterioration of heart tissue due to cessation of the heart's blood supply, which may result from a blood clot obstructing the coronary arteries, the major blood vessels supplying the heart. Heparin is a polysaccharide, or glucose compound, that prevents the coagulation of blood and the formation of blood clots. The effects of heparin on the development of coronary collaterals (small blood vessels that supplement circulation to the heart when a coronary artery is blocked) and on the function of the heart were examined in 18 patients recovering from an MI. Collateral development was greater in patients receiving heparin than in patients without this treatment. Heart function was indicated by measurements of left ventricular ejection fraction, or the amount of blood emptied from the left ventricle during contraction, and muscle shortening of the infarcted heart tissue. These characteristics improved to a greater extent in patients receiving heparin treatment, compared with patients receiving no treatment. The results demonstrate that heparin preserves left ventricular function as a result of collateral development in patients who have sustained an MI. (Consumer Summary produced by Reliance Medical Information, Inc.)