A STEMI results from which type of occlusion?

A STEMI, or ST-Elevation Myocardial Infarction, results from a complete occlusion of a coronary artery. This condition is characterized by a blockage that significantly reduces or completely stops blood flow to a portion of the heart muscle. The lack of oxygenated blood can cause the heart tissue to become ischemic and ultimately die if not treated promptly.

In the context of a STEMI, a complete occlusion is typically due to a ruptured atherosclerotic plaque that leads to the formation of a thrombus (blood clot) at the site of the rupture. This process completely obstructs blood flow, leading to the characteristic ST elevations seen on an ECG.

Understanding the nature of the occlusion is crucial for timely and effective treatment. Complete occlusion necessitates urgent interventions such as percutaneous coronary interventions (PCI) or thrombolysis to restore blood flow and minimize heart damage. Other options like partial blockage, temporary spasms, or inflammation do not result in the same acute presentation and severity as a complete blockage does, which is why the correct answer focuses on complete occlusion.