How does NSTEMI differ from STEMI?

NSTEMI, or Non-ST Elevation Myocardial Infarction, is characterized by a specific subset of symptoms and ECG findings distinct from those of STEMI (ST-Elevation Myocardial Infarction). The statement that NSTEMI presents with symptoms but shows no ST elevation on ECG accurately captures the essence of this condition. In NSTEMI, the arterial blockage is typically less severe compared to STEMI, leading to partial occlusion of a coronary artery. This situation results in ischemia of the heart muscle, which can cause chest pain and other symptoms typical of a heart attack, but it does not manifest as ST elevation on the ECG tracing.

In contrast, the other options miss critical defining features of NSTEMI. For example, NSTEMI does not involve ST elevation; it often presents with a variety of symptoms including chest discomfort, shortness of breath, and fatigue. The assertion that NSTEMI is always resulting in heart failure is misleading, as not every patient with NSTEMI progresses to heart failure; the degree of heart damage can vary. Furthermore, stating that NSTEMI is caused by bacterial infections is inaccurate, as NSTEMI is primarily caused by obstructive coronary artery disease rather than infections.