Timing of Complete Revascularization Stratified by Index Presentation During On- and Off-Hours

Recent trials suggested immediate complete revascularization (ICR) as a safe alternative to staged complete revascularization (SCR), but the impact of the respective percutaneous coronary intervention strategies between on- versus off-hours is unclear. On-hours was defined as an index revascularization performed between 8:00 a.m. and 6:00 p.m., Monday to Friday, or else the procedure was defined as performed during off-hours. The primary end point consisted of a composite of all-cause mortality, myocardial infarction, unplanned ischemia-driven revascularization, and cerebrovascular events at 1-year follow-up. We used Cox regression models to relate randomized treatment with study end points. We evaluated multiplicative and additive interactions between on- versus off-hours and randomized treatment. The BIOVASC (Percutaneous Complete Revascularization Strategies Using Sirolimus Eluting Biodegradable Polymer Coated Stents in Patients Presenting With Acute Coronary Syndromes and Multivessel Disease) trial enrolled 1,097 and 428 patients during on- and off-hours, respectively. Patients randomized during off-hours were more likely to present with ST-segment elevation myocardial infarction (66.4% vs 29.5%, p