Impact of day versus night as intervention time on the outcomes of primary angioplasty for acute myocardial infarction.

BACKGROUND

Conflicting datas exist regarding the outcomes of primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) when the intervention is performed during night hours.

METHODS AND RESULTS

2,644 consecutive patients with STEMI (mean age 56.7 +/- 11.9, years, 2,188 male) undergoing primary PCI between October 2003 and March 2008 were retrospectively enrolled into this study (single high-volume center: >3,000 PCIs/year). Day time was defined according to intervention between 08:00 am and 06:00 pm and night as intervention time between 06:00 pm and 08:00 am. 1,141 patients (43.2%) were treated during the day and 1,503 (56.8%) at night. The baseline characteristics of both groups were similar except for more frequent hypertension (42.6 vs. 36.5%; P = 0.002), women (19.7 vs. 15.4%; P = 0.003), and old (> or =75 y) patients (9.6 vs. 7.4; P = 0.046) in the day time group. Compared with those treated during night time, day time patients had longer angina-reperfusion times (mean, 205 vs. 188 minutes, P = 0.016). Door-to-balloon times were similar (P = 0.87), and less than 90 minutes in both groups. There were no differences concerning clinical events and PCI success between the two groups. Hospital mortality was 6.1% during the day and 5.2% during the night (OR 0.98, 95% CI 0.7-1.36; P = 0.89). The median follow-up time was 21 months. The Kaplan-Meier survival plot for long-term cardiovascular death was not different for both groups (P = 0.78). In-hospital and long-term cardiovascular mortality was also similar in shock and nonshock subgroups.

CONCLUSIONS

Primary PCI can be performed safely during the night at a high-volume PCI center with suitable and effective organization of cardiology department and catheterisation laboratory with 24 hours per day, 7 days per week onsite staffing.