Primary percutaneous coronary intervention during on- vs off-hours in patients with ST-elevation myocardial infarction. Results from EUROTRANSFER Registry.

Background: Primary percutaneous coronary intervention (PPCI) is regarded as the treatment of choice for ST elevation myocardial infarction (STEMI) patients. It has been emphasised that only experienced centres with round-the-clock cathlab facilities should perform PPCI. Some investigators have doubted whether PPCI performed during 'off-hours' is as effective and safe as that performed during regular hours. Papers supporting both possibilities have been published.
Aim: To investigate whether off-hours PPCI is associated with impaired immediate and long-term outcomes based on a contemporary European registry study.
Methods: Consecutive data on STEMI patients referred for PPCI in hospital STEMI networks between November 2005 and January 2007 was gathered. Patients were divided into two groups: PPCI performed during 'on-hours' and PPCI performed during 'off-hours (including Saturdays and Sundays)'.
Results: Data from a total of 1,650 patients were collected in the EUROTRANSFER Registry. There were 1,005 patients in the off-hours group (61%) and 645 (39%) patients in the on-hours group. Patients in both groups did not differ in baseline demographics. Thrombolysis before admission to cathlab was more frequently administered to patients off-hours (4.1% vs 2.3%, p = 0.041). The PPCI complications were rare and occurred in similar frequency in the studied groups. Time from chest pain onset to diagnosis of STEMI was shorter in the off-hours group (173 ± 210 vs 183 ± 187, p = 0.007). In-hospital mortality was 3.4% in the on-hours group and 4.3% in the off-hours group (NS).
Conclusions: The PPCI performed in high-volume, experienced invasive cardiology centres in Europe during off-hours is associated with a comparable outcome and safety profile as PPCI performed during regular working hours.