Percutaneous coronary intervention during on- and off-hours in patients with ST-segment elevation myocardial infarction

Introduction There are conflicting data on the clinical outcomes of percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) based on time of intervention. Concerns have been postulated regarding equally effective in-hospital outcomes for STEMI patients treated with PCI during normal working hours as compared to group treated off-hours. Purpose The aim of this study was to assess clinical outcomes in “real-world” patients with STEMI treated with PCI during off-hours and regular hours of work. Methods To avoid possible bias related to the non-randomized design, a propensity score was calculated to compare off- and on-hours groups. The study group consisted of 37, 469 matched pairs in STEMI treated with PCI and stent implantation between 2014 and 2018 during regular hours (weekdays 7:00 AM to 16:59 PM) and off-hours (weekdays between 17:00 PM and 06:59AM, weekends, and holidays) in 151 tertiary invasive cardiology centers in Poland (the ORPKI Polish National Registry). Results No differences were reported between both groups in baseline characteristics after the propensity score match (PSM). There were no differences in time from pain to first contact (p=0.2) and door to balloon time between both groups (p=0.7). After PSM higher radiation dose was observed in off-hours group (1055.18 (±1006.52) vs. 1081.59 (±1003.25)[mGy]; p=0.001). However, there was no difference in total amount of contrast (on-hours vs. off-hours: 175.69 (±74.71) vs. 176.48 (±74.41)[ml]; p=0.1, respectively). Similar rate of periprocedural complications was observed between both groups of patients, includind stroke, access-site-related bleeding, allergic reaction and coronary artery perforation. However, procedures performed during off-hours were associated with higher incidence of periprocedural death (1.17% (439) vs. 1.49% (559); p=0.001) and periprocedural cardiac arrest (1.76% (658) vs.1.97% (740); p=0.001) as compared to PCI conducted within normal working hours. Conclusions Percutaneous coronary intervention in STEMI performed durgin off-hours might be associated with higher rate of periprocedural mortality and higher radiation dose as compared to procedures conducted during regular working hours. Funding Acknowledgement Type of funding source: None