In patients with acute myocardial infarction (AMI) and multivessel disease, fractional flow reserve (FFR) is better than angiography to select non-culprit lesions for intervention, according to new randomized trial results. Joo-Yong Hahn, MD, PhD, of Samsung Medical Center, Seoul, South Korea, reported these findings from the FRAME-AMI study Sunday at the European Society of Cardiology (ESC) Congress 2022 in Barcelona, Spain. FRAME-AMI was an investigator-initiated, randomized, multicenter trial at 14 sites in South Korea. Patients were eligible if they had AMI and non-infarct-related artery (IRA) lesions (>50% diameter stenosis by visual estimation) amenable to percutaneous coronary intervention (PCI). Non-IRA lesions with an FFR of 0.80 or lower were to be treated with PCI in the FFR group, while non-IRA lesions with diameter stenosis >50% on visual estimation were treated with PCI in the angiography group. The primary endpoint was a composite of all-cause death, MI or unplanned revascularization. Between August 2016 and December 2020, a total of 562 patients underwent randomization. The average age was 63 years, and 16% were women. Non-IRA lesions were treated by immediate PCI after successful treatment of IRA in 337 patients (60.0%) and by staged procedure during the same hospitalization in 225 patients (40.0%). During a median follow-up of 3.5 years (interquartile range: 2.7–4.1 years), the primary endpoint occurred in 18 of 284 patients in the FFR group and 40 of 278 patients in the angiography group (Kaplan-Meier event rates at 4 years, FFR 7.4% vs. angiography 19.7%; hazard ratio [HR] 0.43; 95% confidence interval [CI] 0.25–0.75; p=0.003). The incidence of death was significantly lower in the FFR group compared with the angiography group, occurring in five patients versus 16 patients, respectively (Kaplan-Meier event rates at 4 years, FFR 2.1% vs. 8.5%; HR 0.30; 95% CI 0.11–0.83; p=0.020). The incidence of myocardial infarction was also significantly lower in the FFR group compared with the angiography group, occurring in seven patients versus 21 patients, respectively (Kaplan-Meier event rates at 4 years, FFR 2.5% vs. angiography 8.9%; HR 0.32; 95% CI 0.13–0.75; p=0.009). Ten patients in the FFR group had an unplanned revascularization compared with 16 patients in the angiography group, with no significant difference between the two groups (Kaplan–Meier event rates at 4 years, FFR 4.3% vs. 9.0%; HR 0.61; 95% CI 0.28–1.34; p=0.216). Hahn concluded that among patients with AMI and multivessel coronary artery disease, a strategy of selective PCI of non- IRA lesions using FFR-guided decision making was superior to a strategy of routine PCI based on angiographic diameter stenosis in non-IRA lesions in terms of a composite of death, MI or repeat revascularization. Hahn said during a press conference that the use of FFR is growing and that he believes this study will contribute to its increasing use. He added that he hopes to conduct this study on a larger scale in the near future. The FRAME-AMI trial was funded by Medtronic, Biotronik, Chong Kun Dang Pharmaceutical and JW Pharmaceutical.