Patient delay and benefit of timely reperfusion in ST-segment elevation myocardial infarction.

Background: In patients with ST-segment elevation myocardial infarction (STEMI), it is unknown how patient delay modulates the beneficial effects of timely reperfusion.

Aims: To assess the prognostic significance of a contact-to-balloon time of less than 90 min on in-hospital mortality in different categories of symptom-onset-to-first-medical-contact (S2C) times.

Methods: A total of 20 005 consecutive patients from the Feedback Intervention and Treatment Times in ST-segment Elevation Myocardial Infarction (FITT-STEMI) programme treated with primary percutaneous coronary intervention (PCI) were included.

Results: There were 1554 deaths (7.8%) with a J-shaped relationship between mortality and S2C time. Mortality was 10.0% in patients presenting within 1 hour, and 4.9%, 6.0% and 7.3% in patient groups with longer S2C intervals of 1-2 hours, 2-6 hours and 6-24 hours, respectively. Patients with a short S2C interval of less than 1 hour (S2C<60 min) had the highest survival benefit from timely reperfusion with PCI within 90 min (OR 0.27, 95% CI 0.23 to 0.31, p<0.0001) as compared with the three groups with longer S2C intervals of 1 hour
Conclusions: Timely reperfusion with a contact-to-balloon time of less than 90 min is most effective in patients presenting with short S2C intervals of less than 1 hour, but has also beneficial effects in patients with S2C intervals of up to 24 hours.

Trial Registration Number: NCT00794001.