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

Abstract

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 AM and 6 PM, Monday to Friday, or else the procedure was defined as performed during off-hours. The primary endpoint 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 endpoints. We evaluated multiplicative and additive interactions between on- vs. off-hours and randomized treatment.The BIOVASC trial enrolled 1097 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 < 0.001). The composite primary outcome occurred in 8.4% and 10.1% of patients randomized to ICR and SCR respectively during on-hours (HR 0.80, 95% CI 0.54 to 1.19). During off-hours the primary composite outcome occurred in 5.4% and 7.7% in ICR and SCR (0.69, 95% CI 0.32 to 1.46) with no evidence of a differential effect (interaction pmultiplicative = 0.70, padditive = 0.56). No differential effect was found between treatment allocation and on- versus off-hours in any of the secondary outcomes.In conclusion, no differential treatment effect was found when comparing immediate complete revascularization versus staged complete revascularization in patients presenting with acute coronary syndrome and multivessel disease during on- or off-hours.