What defines an "ischemic" cardiomyopathy?

An ischemic cardiomyopathy is specifically defined by a decrease in cardiac function that arises as a result of myocardial ischemia or infarction. Myocardial ischemia refers to a reduction in blood flow to the heart muscle, often due to coronary artery disease. This lack of adequate blood supply can lead to damage of heart tissue, resulting in impaired cardiac function. Over time, the heart can become weaker and less efficient, manifesting in symptoms of heart failure or reduced exercise tolerance. This concept is fundamental, as it directly ties the cardiac structural changes and functional decline to underlying ischemic events.

The other definitions provided do not accurately characterize ischemic cardiomyopathy. For instance, an increase in cardiac output due to chronic hypertension relates to a different pathological process, while enlargement of the left atrium with normal ventricular function typically describes a different abnormality. Additionally, a preserved ejection fraction alongside mechanical dysfunction suggests a scenario seen in conditions like heart failure with preserved ejection fraction (HFpEF), which is not synonymous with ischemic cardiomyopathy. Therefore, understanding the link between ischemia, infarction, and cardiac function is crucial for identifying and managing ischemic cardiomyopathy effectively.