P5602Impact of preprocedural TIMI flow on clinical outcome in low-risk patients with ST-elevation myocardial infarction: results from the ATLANTIC study

Abstract

Background: Previous studies have shown that the thrombolysis in myocardial infarction (TIMI) flow grade 0/1 before primary percutaneous coronary interven‐tion (PCI) for ST‐elevation myocardial infarction (STEMI) is associated with a worse clinical outcome. However, it is unclear whether the same is true in pa‐tients with ongoing STEMI of less than 6 hours' duration, rapid reperfusion and modern guideline‐adherent therapy. Methods: The multicenter, randomized, double‐blind ATLANTIC (Administration of Ticagrelor in the Cath Lab or in the Ambulance for New ST Elevation Myocardial Infarction to Open the Coronary Artery) study compared prehospital versus in‐hospital treatment with ticagrelor in patients with acute STEMI. For this analysis, patients were divided into three groups according to the preprocedural TIMI flow grade of the infarct vessel: TIMI 0/1, TIMI 2, and TIMI 3. Results: From a total of 1,680 patients, 1,113 (66.3%) had TIMI 0/1, 279 (16.6%) TIMI 2, and 288 (17.1%) TIMI 3 flow grade before primary PCI. The rate of TIMI flow grade <3 (21.3, 22.8, and 2.6%) and incomplete ST resolution after PCI (45.6, 47.5, and 39.0%) were lowest in the group with TIMI 3 patency before PCI. At 30 day, the composite ischemic endpoint (5.5, 2.9, and 2.1%) and all‐cause death (3.0, 1.4, and 2.1%) were highest in patients with TIMI flow grade 0/1. Af‐ter adjustment for age, sex, body mass index, TIMI Risk Score, arterial access, glycoprotein IIb/IIIa inhibitor before PCI, infarct localization and pre‐PCI ST reso‐lution, preprocedural TIMI flow grade was not an independent predictor of major adverse ischemic events within 30 days (odds ratio 1.89, 95% confidence interval 0.74‐4.85). Rates of major bleeding events were similar among the three groups. Definite stent thrombosis only occurred in patients with initial TIMI flow grade 0/1 (1.0%). Among those, patients with prehospital administration of ticagrelor were less often affected (0.3 versus 1.3%, P<0.05). Conclusion: In this post‐hoc analysis of the ATLANTIC study, preprocedural TIMI flow grade was not independently associated with a higher rate of other adverse ischemic events. However, only patients with preprocedural TIMI flow 0/1 devel‐oped definite stent thrombosis.