STEMI usually involves complete occlusion of which type of artery?

STEMI usually involves complete occlusion of which type of artery?

• A. Pulmonary artery
• B. Renal artery
• C. Coronary sinus
• D. Epicardial coronary artery

Answer: (D)

STEMI happens when a major artery supplying the heart muscle becomes completely blocked, cutting off blood flow to a region of the heart. The arteries that cause this are the epicardial coronary arteries—the large surface vessels that deliver oxygenated blood to the myocardium. When one is totally occluded by a thrombus (often after plaque rupture), the affected heart tissue undergoes full-thickness ischemia, producing the ST elevations seen on the ECG. The other vessels listed don’t supply the heart muscle in the way that causes a STEMI: the pulmonary artery carries blood from the heart to the lungs, so a blockage there affects the lungs, not the heart muscle; the renal artery supplies the kidneys; the coronary sinus is a venous channel draining blood from the heart. Occlusion of these would lead to different problems, not a transmural myocardial infarction.

STEMI happens when a major artery supplying the heart muscle becomes completely blocked, cutting off blood flow to a region of the heart. The arteries that cause this are the epicardial coronary arteries—the large surface vessels that deliver oxygenated blood to the myocardium. When one is totally occluded by a thrombus (often after plaque rupture), the affected heart tissue undergoes full-thickness ischemia, producing the ST elevations seen on the ECG.

The other vessels listed don’t supply the heart muscle in the way that causes a STEMI: the pulmonary artery carries blood from the heart to the lungs, so a blockage there affects the lungs, not the heart muscle; the renal artery supplies the kidneys; the coronary sinus is a venous channel draining blood from the heart. Occlusion of these would lead to different problems, not a transmural myocardial infarction.