Myocardial infarctions​

A) ​are commonly known as heart attacks.
B) ​are seldom life-threatening, but serve as a signal of possible heart disease.
C) ​result from loss of oxygen to the brain.
D) ​fit none of these descriptions.

Myocardial infarctions (MI) are commonly known as heart attacks. They occur when blood flow to a part of the heart muscle is blocked, leading to tissue damage and possible failure of the heart to pump effectively. MI can be life-threatening and are a major cause of death worldwide. Option B is incorrect because MI are a serious health concern and it's not true that they serve only as a signal of possible heart disease. Option C is incorrect because the brain is not affected directly by MI, but rather the heart muscle. Option D is incorrect because MI are a well-defined medical condition.