Consistent benefit of physiology-guided complete revascularization across the spectrum of frailty in older patients with myocardial infarction: a prespecified analysis of the FIRE trial

BACKGROUND: The number of older patients admitted with myocardial infarction (MI) is increasing, and their clinical profiles range from very fit to frail and functionally impaired. OBJECTIVES: To evaluate whether the benefits of complete revascularization are consistent across subpopulations of older MI patients stratified by the Clinical Frailty Scale (CFS). METHODS: In the FIRE trial, 1445 patients aged ≥75 years with MI and multivessel disease were randomized to either complete or culprit-only revascularization. Overall, 1010 patients (70%) were stratified according to CFS (scores 1-3 non-frail, 4 pre-frail, 5-9 frail). The primary endpoint was a 3-year composite of death, MI, stroke, or ischemia-driven revascularization. RESULTS: Of the stratified cohort, 523 (52%) were non-frail, 304 (30%) pre-frail, and 183 (18%) frail. Increasing frailty was significantly associated with a higher risk of the primary endpoint (HR 1.62, 95% CI 1.19-2.20; P = .002). Complete revascularization reduced the primary endpoint with no significant interaction between revascularization strategy and CFS category (p for interaction = 0.769). The benefit of complete versus culprit-only revascularization remained consistent across the full range of CFS scores. Similar findings were observed for secondary endpoints, and no significant interaction emerged for safety outcomes. CONCLUSIONS: Frailty, as assessed by the CFS, was independently associated with adverse outcomes. Complete revascularization was effective regardless of frailty status and should be considered in all older MI patients with multivessel disease undergoing an invasive strategy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03772743.