Background: Empagliflozin reduces the risk of heart failure (HF) events in patients with type 2 diabetes at high cardiovascular risk, chronic kidney disease, or prevalent HF irrespective of ejection fraction. Whereas the EMPACT-MI trial (Effect of Empagliflozin on Hospitalization for Heart Failure and Mortality in Patients With Acute Myocardial Infarction) showed that empagliflozin does not reduce the risk of the composite of hospitalization for HF and all-cause death, the effect of empagliflozin on first and recurrent HF events after myocardial infarction is unknown., Methods: EMPACT-MI was a double-blind, randomized, placebo-controlled, event-driven trial that randomized 6522 patients hospitalized for acute myocardial infarction at risk for HF on the basis of newly developed left ventricular ejection fraction of <45% or signs or symptoms of congestion to receive empagliflozin 10 mg daily or placebo within 14 days of admission. In prespecified secondary analyses, treatment groups were analyzed for HF outcomes., Results: Over a median follow-up of 17.9 months, the risk for first HF hospitalization and total HF hospitalizations was significantly lower in the empagliflozin compared with the placebo group (118 [3.6%] versus 153 [4.7%] patients with events; hazard ratio, 0.77 [95% CI, 0.60, 0.98]; P =0.031, for first HF hospitalization; 148 versus 207 events; rate ratio, 0.67 [95% CI, 0.51, 0.89]; P =0.006, for total HF hospitalizations). Subgroup analysis showed consistency of empagliflozin benefit across clinically relevant patient subgroups for first and total HF hospitalizations. The need for new use of diuretics, renin-angiotensin modulators, or mineralocorticoid receptor antagonists after discharge was less in patients randomized to empagliflozin versus placebo (all P <0.05)., Conclusions: Empagliflozin reduced the risk of HF in patients with left ventricular dysfunction or congestion after acute myocardial infarction., Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04509674., Competing Interests: Disclosures Dr Hernandez has served as a consultant for Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb, Cytokinetics, Eidos, GlaxoSmithKline, Intellia, Intercept, MyoKardia, Novartis, Novo Nordisk, Prolaio, and TikkunLev; and has received research funding from American Regent, Amgen, Bayer, Boehringer Ingelheim, Lilly, Merck, Novartis, Novo Nordisk, and Verily. Dr Bhatt has served on advisory boards for ANGIOWave, Bayer, Boehringer Ingelheim, CellProthera, Cereno Scientific, Elsevier Practice Update Cardiology, High Enroll, Janssen, Level Ex, McKinsey, Medscape Cardiology, Merck, MyoKardia, NirvaMed, Novo Nordisk, PhaseBio, PLx Pharma, Stasys; on the board of directors for American Heart Association New York City, ANGIOWave (stock options), Bristol Myers Squibb (stock), DRS.LINQ (stock options), and High Enroll (stock); has served as a consultant for Broadview Ventures, GlaxoSmithKline, Hims, SFJ, and Youngene; has served on data monitoring committees for Acesion Pharma, Assistance Publique-Hôpitaux de Paris, Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute, for the PORTICO trial, funded by St Jude Medical, now Abbott), Boston Scientific (chair, PEITHO trial), Cleveland Clinic, Contego Medical (chair, PERFORMANCE 2), Duke Clinical Research Institute, Mayo Clinic, Mount Sinai School of Medicine (for the ENVISAGE trial, funded by Daiichi Sankyo; for the ABILITY-DM trial, funded by Concept Medical; for ALLAY-HF, funded by Alleviant Medical), Novartis, Population Health Research Institute, and Rutgers University (for the NIH-funded MINT Trial); has received honoraria from American College of Cardiology (senior associate editor, Clinical Trials and News, ACC.org; chair, ACC accreditation oversight committee), Arnold and Porter law firm (work related to Sanofi/Bristol Myers Squibb clopidogrel litigation), Baim Institute for Clinical Research (formerly Harvard Clinical Research Institute; RE-DUAL PCI clinical trial steering committee funded by Boehringer Ingelheim; AEGIS-II executive committee funded by CSL Behring), Belvoir Publications (editor-in-chief, Harvard Heart Letter), Canadian Medical and Surgical Knowledge Translation Research Group (clinical trial steering committees), CSL Behring (AHA lecture), Cowen and Company, Duke Clinical Research Institute (clinical trial steering committees, including for the PRONOUNCE trial, funded by Ferring Pharmaceuticals), HMP Global (editor-in-chief, Journal of Invasive Cardiology), Journal of the American College of Cardiology (Guest editor; associate editor), K2P (co-chair, interdisciplinary curriculum), Level Ex, Medtelligence/ReachMD (CME steering committees), MJH Life Sciences, Oakstone CME (course director, Comprehensive Review of Interventional Cardiology), Piper Sandler, Population Health Research Institute (for the COMPASS operations committee, publications committee, steering committee, and USA national co-leader, funded by Bayer), WebMD (CME steering committees), and Wiley (steering committee); other: Clinical Cardiology (deputy editor); is named on a patent for sotagliflozin assigned to Brigham and Women’s Hospital, which was assigned to Lexicon (neither Dr Bhatt nor Brigham and Women’s Hospital receives any income from this patent); has received research funding from Abbott, Acesion Pharma, Afimmune, Aker Biomarine, Alnylam, Amarin, Amgen, AstraZeneca, Bayer, Beren, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb, Cardax, CellProthera, Cereno Scientific, Chiesi, CinCor, Cleerly, CSL Behring, Eisai, Ethicon, Faraday Pharmaceuticals, Ferring Pharmaceuticals, Forest Laboratories, Fractyl, Garmin, HLS Therapeutics, Idorsia, Ironwood, Ischemix, Janssen, Javelin, Lexicon, Lilly, Medtronic, Merck, Moderna, MyoKardia, NirvaMed, Novartis, Novo Nordisk, Otsuka, Owkin, Pfizer, PhaseBio, PLx Pharma, Recardio, Regeneron, Reid Hoffman Foundation, Roche, Sanofi, Stasys, Synaptic, The Medicines Company, Youngene, and 89Bio; has received royalties from Elsevier (editor, Braunwald’s Heart Disease); has served as site coinvestigator for Abbott, Biotronik, Boston Scientific, CSI, Endotronix, St Jude Medical (now Abbott), Philips, SpectraWAVE, Svelte, and Vascular Solutions; has served as trustee for American College of Cardiology; and performed unfunded research for FlowCo. Dr Butler has served as a consultant to Abbott, American Regent, Amgen, Applied Therapeutic, AskBio, Astellas, AstraZeneca, Bayer, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb, Cardiac Dimension, Cardiocell, Cardior, CSL Bearing, CVRx, Cytokinetics, Daxor, Edwards, Element Science, Faraday, Foundry, G3P, Innolife, Impulse Dynamics, Imbria, Inventiva, Ionis, Lexicon, Lilly, LivaNova, Janssen, Medtronic, Merck, Occlutech, Owkin, Novartis, Novo Nordisk, Pfizer, Pharmacosmos, Pharmain, Prolaio, Regeneron, Renibus, Roche, Salamandra, Sanofi, SC Pharma, Secretome, Sequana, SQ Innovation, Tenex, Tricog, Ultromics, Vifor, and Zoll. Dr Goto reports serving as Associate Editor for Circulation and receipt of a steering committee fee from the Duke Clinical Research Institute for EMPACT-MI. Dr Lopes reports research grants or contracts from Amgen, Bristol Myers Squibb, GlaxoSmithKline, Medtronic, Pfizer, and Sanofi-Aventis; funding for educational activities or lectures from Pfizer, Daiichi Sankyo, and Novo Nordisk; and funding for consulting or other services from Bayer, Boehringer Ingelheim, Bristol Myers Squibb, and Novo Nordisk. Dr Amir reports serving as National PI-Steering committee member for the study and participated in paid lectures and advisory board meetings and clinical trials in Dr Amir’s department at Boehringer Ingelheim. Dr Beyes-Genis has lectured or participated in advisory boards for Abbott, AstraZeneca, Bayer, Boehringer-Ingelheim, Medtronic, Novartis, Novo Nordisk, Roche Diagnostics, and Vifor. Dr Bahit reports modest honorarium from MSD, Pfizer, Bristol Myers Squibb, CSL Behring, Janssen, Boehringer Ingelheim, and Anthos Therapeutics. Dr Bauersachs received honoraria for lectures/consulting from Novartis, Vifor, Bayer, Pfizer, Boehringer Ingelheim, AstraZeneca, Cardior, CVRx, BMS, Amgen, Corvia, Norgine, Edwards, and Roche not related to this article; and research support for Dr Bauersachs’ department from Zoll, CVRx, Abiomed, Norgine, and Roche, not related to this article. Dr Schou reports lecture fees from Novartis, Astra Zeneca, Bohringer, and Novo Nordisk. Dr Steg reports research grants from Amarin and Sanofi; clinical trial participation for Amarin, Amgen, AstraZeneca, Idorsia, Janssen, Novartis, Novo-Nordisk, and Sanofi; consulting or speaking for Amarin, Amgen, and Novo-Nordisk; and serving as senior associate editor at Circulation. Dr Parikh reports serving as a consultant for Medtronic, Inc and receipt of an institutional research grant from Abbott and Edwards Lifesciences. Dr Januzzi reports participation as a trustee of the American College of Cardiology, board member of Imbria Pharmaceuticals, and director at Jana Care; has received research support from Abbott, Applied Therapeutics, Bayer, BBMS, HeartFlow Inc, Innolife, and Roche Diagnostics, and consulting income from Abbott, AstraZeneca, Bayer, Beckman, Boehringer-Ingelheim, Janssen, Medtronic, Novartis, Prevencio, Quidel/Ortho, Roche Diagnostics, and Vascular Dynamics; and participates in clinical end point committees or data safety monitoring boards for Abbott, AbbVie, Bayer, CVRx, Medtronic, Pfizer, Roche Diagnostics, and Takeda. Dr Goodman reports research grant support (eg, steering committee or data and safety monitoring committee) or speaker or consulting honoraria (eg, advisory boards) from Amgen, Anthos Therapeutics, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol Myers Squibb, CSL Behring, CYTE Ltd, Daiichi-Sankyo/American Regent, Eli Lilly, Esperion, Ferring Pharmaceuticals, HLS Therapeutics, Idorsia, JAMP Pharma, Merck, Novartis, Novo Nordisk A/C, Pendopharm/Pharmascience, Pfizer, Regeneron, Sanofi, Servier, Tolmar Pharmaceuticals, and Valeo Pharma; and salary support or honoraria from the Heart and Stroke Foundation of Ontario/University of Toronto (Polo) Chair, Canadian Heart Failure Society, Canadian Heart Research Centre and MD Primer, Canadian VIGOUR Centre, Cleveland Clinic Coordinating Centre for Clinical Research, Duke Clinical Research Institute, New York University Clinical Coordinating Centre, PERFUSE Research Institute, and TIMI Study Group (Brigham Health). Dr van der Meer reports support from the European Research Council (ERC CoG 101045236, DISSECT-HF); the UMCG, which employs Dr van der Meer, received consultancy fees or grants from Novartis, Pharmacosmos, Vifor Pharma, Astra Zeneca, Pfizer, Pharma Nord, BridgeBio, Novo Nordisk, Daiichi Sankyo, Boehringer Ingelheim, and Ionis. Dr Petrie reports research funding from Boehringer Ingelheim, Roche, SQ Innovations, Astra Zeneca, Novartis, Novo Nordisk, Medtronic, Boston Scientific, and Pharmacosmos; and consultancy or trial committee participation from Akero, Applied Therapeutics, Amgen, AnaCardio, Biosensors, Boehringer Ingelheim, Novartis, Astra Zeneca, Novo Nordisk, AbbVie, Bayer, Horizon Therapeutics, Takeda, Cardiorentis, Pharmacosmos, Siemens, Eli Lilly, Vifor, New Amsterdam, Moderna, Teikoku, LIB Therapeutics, and 3R Lifesciences. Dr Parkhomenko reports research grants and personal fees from Bayer, Amgen, Astra Zeneca, Boehringer Ingelheim, BMS/Pfizer, and Daiichi-Sankyo. Dr Vinereanu reports research grants and consultancy fees from Boehringer Ingelheim and research grants from Bayer Healthcare, Novartis, and Servier Pharmaceuticals LLC. Dr Zieroth reports research grant support, served on advisory boards for, or had speaker engagements with AstraZeneca, Bayer, BMS, Boehringer Ingelheim, Cytokinetics, Eli Lilly, GSK, Janssen, Medtronic, Merck, Novartis, Novo Nordisk, Otsuka, Pfizer, Roche, Salubrisbio, Servier, and Vifor Pharma; and serves on a clinical trial committee or as a national lead for studies sponsored by AstraZeneca, Bayer, Boehringer Ingelheim, Merck, Novartis and Pfizer; nonindustry participation includes Canadian Medical and Surgical KT Group, CCS, CHFS, Charite, EOCI, Liv, Medscape, Ology, PACE-CME, Radcliffe, Reach MD, and Translational Medicine Academy. Dr Jones reports research grants from Bayer, Boehringer Ingelheim, Merck, Novartis, PCORI, and the National Institutes of Health. Drs Seide, Mattheus, Zwiener, Sumin, Gasior, Jamal, and Brueckmann are employees of Boehringer Ingelheim.