What is a heart attack characterized by?

A heart attack, or myocardial infarction, occurs when the blood flow to a part of the heart is blocked, usually by a clot in a coronary artery. This blockage prevents oxygen-rich blood from reaching heart muscle, which can lead to damage or death of the heart tissue. Therefore, the defining characteristic of a heart attack is indeed anything that obstructs blood vessels supplying the heart.

While an increase in heart rate, irregular heartbeat, or a drop in blood pressure may be symptoms or consequences of a heart attack, they do not encapsulate the fundamental cause of the event. The diverse range of potential symptoms and related conditions are often consequences of the heart's response to the blockage, rather than defining characteristics of a heart attack itself. Thus, understanding that a heart attack is primarily characterized by a blockage in the vessels supplying the heart is crucial for identifying this life-threatening condition.