Spontaneous reperfusion (SR) in ST-elevation myocardial infarction has traditionally been assessed by coronary angiography. Recently, spontaneous reperfusion would be defined by reduction of ST-segment elevation and resolution of pain. In our study, we undertook a systematic assessment of SR using both clinical and angiographic techniques.

To determine predictors of better prognosis in spontaneous reperfused STEMI.

This was a retrospective study which included all patients diagnosed with STEMI and hospitalized in the cardiology department of Monastir hospital, Tunisia and treated by primary PCI, between 2008 and 2017. We compared clinical characteristics and outcomes in the two groups.

Three hundred fifty-five patients are treated by primary percutaneous coronary intervention (PCI) and were studied: Electrocardiographic SR (>/=70% ST-segment resolution) occurred in 18% of patients and angiographic SR (pre-PCI Thrombolysis in Myocardial Infarction (TIMI) 3 flow) in 17.7% of patients. Thirty-day clinical outcomes of patients with ECG SR versus no ECG SR tended to have lower mortality (0% vs. 2.4%, P=.061), a lower composite of death/shock/congestive heart failure (6.9% vs. 12.2%, P=.148), and significant reductions in death/reinfarction (0% vs. 5.6%, P=.014). By contrast, no such significative differences were evident in patients with angiographic SR versus no SR for death (2.8% vs. 3.0%, P=1.00), death/shock/congestive heart failure (10.3% vs. 11.8%, P=.498), or death/reinfarction (2.3% vs. 5.2%, P=.409).

The frequency of SR was comparable using either ECG or angiographic criteria. Clinical outcomes were better assessed with ECG SR. These results support the role of ECG in detecting reperfusion versus infract-related artery epicardial patency alone.