What term refers to damage to a layer of the heart muscle?

The term that refers specifically to damage to a layer of the heart muscle is cardiomyopathy. This condition involves a deterioration of the myocardial tissue, which can affect the heart's ability to pump blood effectively. In cardiomyopathy, damage can be due to various factors, including genetic predispositions, prolonged high blood pressure, or the effects of certain infections and toxins. This damage can lead to significant heart dysfunction, heart failure, and other complications related to the heart's functionality.

While other medical conditions listed may affect the heart or its function, they do not directly specify damage to the heart muscle itself. For instance, cardiac arrest refers to a sudden stop in heart function, while myocarditis is inflammation of the heart muscle usually due to an infection or autoimmune response. Coronary artery disease primarily involves the narrowing or blockage of the coronary arteries, which supply blood to the heart muscle but does not specifically refer to damage of the muscle layer itself. Thus, cardiomyopathy is the most appropriate term for this description.