Is myocardial ischemia the same as myocardial infarction?
Apr 07, 2022
Source: Cainiu Health
Dr. Li Man
Introduction
Myocardial ischemia is not necessarily myocardial infarction. Myocardial ischemia generally refers to any condition that impairs blood supply to cardiomyocytes. The classic cause is coronary atherosclerosis, which leads to stenosis of the coronary arteries and consequently relative myocardial hypoperfusion. When coronary artery stenosis exceeds 50%, it is termed coronary artery disease (CAD).
Generally, myocardial ischemia in some patients develops due to prolonged inflammatory stimulation—for example, from prior conditions such as rheumatic heart disease, Kawasaki disease, or thromboangiitis obliterans. If timely and effective anti-inflammatory or antimicrobial treatment is not administered, the myocardium becomes subject to inflammatory injury, leading subsequently to ischemic changes. So—is myocardial ischemia the same as myocardial infarction? Below, we address this question.
Is Myocardial Ischemia the Same as Myocardial Infarction?
Myocardial ischemia is not necessarily myocardial infarction. Myocardial ischemia broadly refers to any condition causing inadequate blood supply to myocardial cells. The classic cause is coronary atherosclerosis, which leads to narrowing of the coronary arteries and consequently relative myocardial hypoperfusion. When coronary artery stenosis exceeds 50%, the condition is typically diagnosed as coronary artery disease (CAD).
Other causes may also induce myocardial ischemia—for instance, shock, poisoning, or severe infection. Carbon monoxide poisoning, for example, interferes with oxygen delivery and release, thereby precipitating myocardial ischemia. In contrast, myocardial infarction (MI) refers specifically to occlusion—either partial or complete—of one or more coronary arteries, resulting in myocardial ischemia severe enough to cause irreversible myocardial cell necrosis and ultimately manifesting clinically as myocardial infarction. Thus, MI represents a severe, life-threatening form of myocardial ischemia.
Therefore, while myocardial ischemia does not always progress to myocardial infarction, myocardial infarction invariably involves myocardial ischemia—and this distinction warrants careful clinical attention.
We hope the above information is helpful to you.
