Introduction Mortality amongst emergency medical admissions has been reported to be higher when patients are admitted to hospital at nights and weekends. We studied the mortality for STEMI patients presenting at different times to a large cardiothoracic centre in the UK with a 24/7 primary PCI (PPCI) service delivered by senior medical staff.

Methods We included all patients who underwent PPCI from September 2009 to November 2011. We divided them into three groups according to the time of admission to our unit as group 1: in-hours (08:00–18: weekdays), group 2: out-of-hours (18:00–08:00 week nights) and group 3: weekend (Saturday 08:00 to Monday 08:00) and bank holidays.

Results Of the 1471 patients who were admitted and underwent PPCI in our unit during the study period, 605 (41.1%), 397 (27%) and 469 (31.9%) were included in group 1, 2 and 3 respectively. Pre-procedure cardiogenic shock was significantly higher in group 1 compared to group 2 (8.9% vs 5.5%, p 0.05), but no other significant difference was noted in the baseline and procedural characteristics between the groups (table 1).

When compared to group 1, door to balloon (DTB) time (median, IQR 29, 24–39 min) was significantly prolonged in group 2 (33, 24–36 min, p 0.004) and group 3 (36, 28–47 min, p<0.0001). There was no difference in DTB time between groups 2 and 3 (p 0.15). However, there was no significant difference in in-hospital mortality (grp 1 vs grp 2 vs grp3: 4.6% vs 4.3% vs 5.3%, p NS), 30-day mortality (6.4% vs 6.3% vs 7%, p NS) or stent thrombosis (0.8% vs 0.8% vs 0.2%, p NS) between the groups (table 2).

Conclusions In this consecutive series of patients admitted to a high volume primary PCI centre, there was no difference in mortality when patients were admitted at night, at the weekend or during regular office hours. The involvement of senior medical staff early in the patients' admission may have contributed to these consistent outcomes.