What is the primary cause of a myocardial infarction (heart attack)?

A myocardial infarction, commonly known as a heart attack, primarily occurs due to a blockage of blood flow to the heart muscle. This blockage is often caused by the buildup of plaque—a mixture of fat, cholesterol, and other substances—within the coronary arteries. When these arteries become narrowed or blocked, the oxygen supply to the heart muscle is reduced or cut off, resulting in damage or death of the heart tissue.

This condition can lead to severe chest pain, discomfort, and even fatal consequences if not treated promptly. While other factors, such as high blood pressure or severe dehydration, can contribute to heart problems, they do not directly cause the blockage that characterizes a myocardial infarction. A blood clot that forms due to plaque rupture can indeed cause this blockage, but the correct answer addresses the broader and primary concept of reduced blood flow to the heart muscle. This understanding is crucial for recognizing the risk factors and potential preventative measures associated with heart disease.