Three-year outcomes with fractional flow reserve- or angiography-guided multivessel percutaneous coronary intervention for myocardial infarction

Background In multivessel disease (MVD) patients with successful primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI), the Flow Evaluation to Guide Revascularization in Multivessel ST-Elevation Myocardial Infarction (FLOWER-MI) trial showed that a fractional flow reserve (FFR)-guided strategy was not superior to an angiography-guided strategy for treatment of non-infarct-related artery lesions regarding the one-year risk of death from any cause, MI, or unplanned hospitalization leading to urgent revascularization. The extension phase of the trial was planned using the same primary outcome to determine whether a difference in outcomes would be observed with a longer follow-up. Methods In this multicenter trial, we randomly assigned patients with STEMI and MVD with successful PCI of the infarct-related artery to receive complete revascularization guided by either FFR (n=586) or angiography (n=577). Results After 3 years, a primary outcome event occurred in 52 of 498 patients in the FFR-guided group and in 44 of 502 patients in the angiography-guided group (hazard ratio[HR], 1.19; 95% confidence interval [CI], 0.79-1.77; P=0.4 ). Death occurred in 22 patients in the FFR-guided group and in 23 in the angiography-guided group (HR, 0.96; 95% CI 0.53-1.71); nonfatal MI in 23 and 14), respectively (HR, 1.63; 95% CI 0.84-3.16); and unplanned hospitalization leading to urgent revascularization in 21 and 18 (HR, 1.15; 95% CI 0.61-2.16), respectively. Conclusions Although event rates in the trial were lower than expected, in patients with STEMI undergoing complete revascularization, an FFR-guided strategy had not a significant benefit over an angiography-guided strategy with respect to the risk of death, MI, or urgent revascularization up to 3 years. (Funded by the French Ministry of Health and Abbott; FLOWER-MI [ClinicalTrials.gov][1] number, [NCT02943954][2].) CLINICAL PERSPECTIVE What Is New? What Are the Clinical Implications? ### Competing Interest Statement FLOWER-MI is an academic study, funded by a grant from the "Programme Hospitalier de Recherche Clinique" (PHRC) issued by the French Ministry of Health. The study was sponsored by Assistance Publique-Hopitaux de Paris, with an unrestricted grant from St. Jude Medical (now Abbott), which provided the coronary pressure guidewire (Radi Medical Systems). The authors are solely responsible for the design and conduct of this study, all study analyses, the drafting and editing of the paper and its final contents. None of the funders had a role in the design and conduct of the study, data collection and management. The steering committee vouches for the accuracy and completeness of the data and analyses and for the fidelity of the trial to the protocol. ### Clinical Trial Trial Registration: FLOWER-MI ClinicalTrials.gov number, [NCT02943954][2] ### Funding Statement FLOWER-MI is an academic study, funded by a grant from the "Programme Hospitalier de Recherche Clinique" (PHRC) issued by the French Ministry of Health. The study was sponsored by Assistance Publique-Hôpitaux de Paris, with an unrestricted grant from St. Jude Medical (now Abbott), which provided the coronary pressure guidewire (Radi Medical Systems). The authors are solely responsible for the design and conduct of this study, all study analyses, the drafting and editing of the paper and its final contents. None of the funders had a role in the design and conduct of the study, data collection and management. The steering committee vouches for the accuracy and completeness of the data and analyses and for the fidelity of the trial to the protocol. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The study protocol has been approved by an ethics committee (CPP Ile de France XI, April 14, 2016). It is registered in the Clinicaltrials.gov registry ([NCT02943954][2]). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The FLOWER MI trial is planning to continue analysis, including post hoc subgroup analysis. Any relevant inquiry should be emailed to Dr. Etienne PUYMIRAT (Email: etienne.puymirat{at}aphp.fr) * ACS : acute coronary syndrome CCS : chronic coronary syndrome COMPLETE : Complete versus Culprit-Only Revascularization Strategies to Treat Multivessel Disease after Early PCI for STEMI FFR : fractional flow reserve FLOWER-MI : Flow Evaluation to Guide Revascularization in Multivessel ST-Elevation Myocardial Infarction MVD : multivessel disease FRAME-AMI : Fractional Flow Reserve vs. Angiography-Guided Strategy for Management of Non-Infarction Related Artery Stenosis in Patients with Acute Myocardial Infarction IRA : infarct-related coronary arteries MACE : major adverse cardiac events PCI : percutaneous coronary intervention STEMI : ST-elevation myocardial infarction [1]: http://ClinicalTrials.gov [2]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02943954&atom=%2Fmedrxiv%2Fearly%2F2023%2F08%2F31%2F2023.08.30.23294648.atom