Frequency and outcomes of STEMI patients presenting between 12 and 24 h after symptom onset: Late-presenting STEMI.

Objectives: To assess the characteristics and prognosis of ST-elevation myocardial infarction (STEMI) patients, presenting between 12 and 24 h after symptom onset, in contemporary regional STEMI systems of care in the United States.

Background: Previous observational studies have been inconsistent regarding the benefit of primary percutaneous coronary intervention (PCI) compared with conservative management for late-presenting STEMI patients and the majority of randomized trials are from the fibrinolytic era.

Methods: Using a two-center registry-based cohort from March 2003 to December 2020, we evaluated the frequency, clinical characteristics, and outcomes of STEMI patients, stratified by symptom onset to balloon time: <3, 3-6, 6-12, and 12-24 h (late presenters).