When should reperfusion therapy be performed after symptom onset for a STEMI?

Reperfusion therapy, such as percutaneous coronary intervention (PCI) or thrombolysis, is crucial for patients experiencing a STEMI (ST-Elevation Myocardial Infarction) as it significantly reduces morbidity and mortality by restoring blood flow to the affected myocardium.

The optimal window for administering reperfusion therapy is within 12 hours of symptom onset. Studies indicate that the greatest benefit is observed when treatment is initiated early, particularly within the first few hours after the onset of symptoms. The goal is to minimize myocardial necrosis and preserve heart function. After the 12-hour mark, the likelihood of successful reperfusion decreases, and the risks associated with thrombolytics may outweigh the potential benefits.

While reperfusion can be considered in select cases beyond 12 hours, such as in patients presenting with ongoing ischemic symptoms or those who have evidence of viability on imaging studies, the general guideline remains that therapy should ideally begin within this timeframe to achieve maximum benefit.