BACKGROUND The objective of this study is to evaluate safety and performance of the Fantom bioresorbable coronary scaffold in the acute setting of myocardial infarction with unstable lesions and thrombogenic milieu. Fantom (Tyrocore, REVA Medical) is composed mainly of an iodinated, polycarbonate copolymer of tyrosine analogs. Fantom is completely radiopaque with thin struts of 125 mm in the second-generation device and as low as 95 mm in the third-generation version. This presentation represents the first report on the 12-month results from the full ST-segment elevation myocardial infarction study population. METHODS Twenty ST-segment elevation myocardial infarction pa tients were enrolled into this prospective, observational study utiliz ing optical coherence tomography–guided primary percutaneous coronary intervention with the sirolimus-eluting Fantom bio resorbable coronary scaffold implantation. The scaffold sizing, posi tioning, and optimization were performed based on optical coherence tomography to achieve full lesion coverage, proper stent expansion (>80%), and strut apposition. Dual antiplatelet therapy was admin istered according to the current guidelines. Patient follow-up is ongoing through 36 months. RESULTS Reported outcomes will include acute technical success, acute procedural success, and clinical procedural success. In addition, the incidences of major cardiac adverse events and scaffold throm bosis imaging outcomes through 12-month follow-up will be pre sented. All patients have recently completed their 12-month follow up. Final event adjudication is in process and will be completed prior to Transcatheter Cardiovascular Therapeutics 2020 annual meeting. CONCLUSION This is the first pilot study evaluating performance of the second-generation Fantom bioresorbable coronary scaffold in ST segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention. Full conclusions will be completed prior to the conference after all data have been analyzed.