Immediate versus staged complete myocardial revascularization in patients with ST-segment elevation myocardial infarction and multivessel disease: A post hoc analysis of the randomized FLOWER-MI trial.

BACKGROUND: In patients with ST-segment elevation myocardial infarction and multivessel disease, percutaneous coronary intervention for non-culprit lesions is superior to treatment of the culprit lesion alone. The optimal timing for non-infarct-related artery revascularization - immediate versus staged - has not been investigated adequately. AIM: We aimed to assess clinical outcomes at 1 year in patients with ST-segment elevation myocardial infarction with multivessel disease using immediate versus staged non-infarct-related artery revascularization. METHODS: Outcomes were analysed in patients from the randomized FLOWER-MI trial, in whom, after successful primary percutaneous coronary intervention, non-culprit lesions were assessed using fractional flow reserve or angiography during the index procedure or during a staged procedure during the initial hospital stay, ≤5 days after the index procedure. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction and unplanned hospitalization with urgent revascularization at 1year. RESULTS: Among 1171 patients enrolled in this study, 1119 (96.2%) had complete revascularization performed during a staged procedure, and 44 (3.8%) at the time of primary percutaneous coronary intervention. During follow-up, a primary outcome event occurred in one of the patients (2.3%) with an immediate strategy and in 55 patients (4.9%) with a staged strategy (adjusted hazard ratio 1.44, 95% confidence interval 0.39-12.69; P=0.64). CONCLUSIONS: Staged non-infarct-related artery complete revascularization was the strategy preferred by investigators in practice in patients with ST-segment elevation myocardial infarction with multivessel disease. This strategy was not superior to immediate revascularization, which, in the context of this trial, was used in a small proportion of patients. Further randomized studies are needed to confirm these observational findings.