What EKG changes are typically seen in a late presentation STEMI?

In the context of a late presentation STEMI (ST-Elevation Myocardial Infarction), the presence of Q waves and ST elevation on the EKG is significant. A STEMI is characterized by the disruption of blood flow to a portion of the heart muscle, often leading to ischemia and subsequent injury.

In the early stages of a STEMI, the EKG shows ST elevation due to acute transmural ischemia. As the ischemic event evolves, particularly in a late presentation, the infarcted myocardial tissue begins to undergo necrosis, which is reflected in the development of Q waves. These Q waves indicate a previous myocardial infarction, marking the necrosis that has occurred in the heart muscle.

ST elevation remains present because it is a hallmark of the acute phase, signifying ongoing ischemia in surrounding myocardial tissues or acute injury. Thus, seeing Q waves alongside ST elevation indicates that the patient is experiencing a more chronic phase of ischemia or may have previously sustained damage that has now become clear on the EKG findings.

The other options do not represent the hallmark characteristics of a late presentation STEMI. Options involving ST depression, T wave inversion, or normal sinus rhythm do not accurately capture the critical findings associated with a STEM