What occurs if blood supply to the myocardium is interrupted?

When blood supply to the myocardium is interrupted, the area of heart muscle without adequate blood flow is deprived of oxygen and nutrients essential for cellular metabolism. This localized lack of blood supply typically leads to ischemia, which can result in cellular injury and, eventually, cell death if the interruption continues for too long.

In the case of myocardial infarction, or a heart attack, only the specific region of the myocardium that is fed by the affected coronary artery will be impacted. This means that while the deprived area may die due to necrosis, the rest of the heart muscle, which receives adequate blood supply from other arteries, can remain viable and functional. This is why the answer identifies that only the deprived area dies, as it reflects the concept that the impact of arterial blockage is localized to the specific area supplied by that artery.

The other scenarios likened to complete muscle death, heart stopping, or syncope are less accurate. In a situation where blood supply is compromised, the heart may continue to beat, and collateral circulation might even provide some compensatory blood flow, preventing widespread myocardial death or total heart failure immediately.