analysis was performed in the studies, that did not present these data in the original reports. 4 weeks was used as primary target, because this is the advised treatment duration in the German, Italian and Chinese consensus group recommendations. The primary outcome was early or late vessel or lesion thrombosis. RESULTS 3034 patients treated with DCB as stand-alone PCI tech- nique (DCB only) were identified in 3 small randomized trials and 11 registries. Between 23 and 76% of patients had had acute coronary syndromes and were treated for 12 months with DAPT according to the published guidelines. 1493 patients had had stable AP and were treated for only 4 weeks with DAPT after DCB for de novo lesions. Amongst these 1493 patients there was no report of acute vessel or lesion thrombosis. Two of the coauthors report additional series of such cases that are not yet published and also show no such signal (Scheller: n¼487 and Eccleshall: n¼140). CONCLUSION While after DCB PCI for in stent restenosis trials used a variable treatment duration with 1-12 months DAPT and the majority of data support a 3-6 months treatment, the DCB only approach in de novo lesions with DAPT for 4 weeks only is supported by a large data base and can be considered as safe. The recently published data from the SCAR registry confirm the observation that vessel thrombosis rate is much smaller with DCB only as compared to PCI with current stents. CATEGORIES CORONARY: Drug-Eluting Balloons and Local Drug Delivery TCT-777 Guided De-Escalation of DAPT in Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention with BVS implantation: A post-hoc Analysis from the Randomized TROPICAL-ACS Trial Lukasz Koltowski, 1 Mariusz Tomaniak, 2 Bartosz Rymuza, 3 Michal Kowara, 4 Radoslaw Parma, 5 Anna Komosa, 6 Mariusz Klopotowski, 7 Tommaso Gori, 8 Daniel Aradi, 9 Kurt Huber, 10 Martin Hadamitzky, 11 Steffen Massberg, 12 Grzegorz Opolski, 4 Dirk Sibbing, 13 Zenon Huczek 14 1 1st Department of Cardiology, Medical University of Warsaw, Warszawa, Poland; 2 Thorax Center, Erasmus MC, Department of Interventional Cardiology, Rotterdam, Netherlands, Medical University of Warsaw, First Department of Cardiology, Warsaw, Poland; 3 Ist Department of Cardiology, Warszawa, Poland; 4 1st Department of Cardiology, Medical University of Warsaw, Warsaw, Poland; 5 Medical University of Silesia, Katowice, Poland; 6 Department of Cardiology, Poznan University of Medical Sciences, Poznan, Poland; 7 Unknown, Warsaw, Poland; 8 University Medical Center Mainz, Mainz, Germany; 9 Heart Center Balatonfüred, Balatonfüred, Hungary; 10 Wilhelminen Hospital, Vienna, Austria; 11 Department of Radiology and Nuclear Medicine, German Heart Center Munich, Munich, Germany; 12 Munich University Clinic, LMU, Munich, Germany; 13 LMU München, Munich, Germany; 14 medical university of warsaw, warsaw, Poland BACKGROUND Platelet function testing (PFT)-guided de-escalation of dual antiplatelet treatment (DAPT) with an early switch from pra- sugrel to clopidogrel was equally effective and safe compared to standard treatment with potent platelet inhibition in acute coronary syndrome (ACS) patients undergoing primary percutaneous coronary intervention (PCI). Bioresorbable vascular scaffolds (BVS) demon- strated an increased risk of device thrombosis, often clustered in the early phase. It remains unknown if the DAPT de-escalation strategy is safe and effective in ACS patients with BVS implantation. METHODS The TROPICAL-ACS trial randomized (1:1) biomarker posi- tive ACS patients who underwent PCI to a DAPT de-escalation group (PFT-guided maintenance therapy with prasugrel or clopidogrel from day 14 after hospital discharge) or to control group (standard treat- ment with prasugrel for 12 months). In this post-hoc analysis, we compared clinical outcomes for the two treatment strategies in ACS patients who received a BVS. RESULTS In the TROPICAL-ACS (n¼2610) there were 151 patients (5.7%) treated with BVS. The primary end-point (cardiovascular death, myocardial infarction, stroke or bleeding  grade 2 according to BARC criteria) occurred in 6 patients (8.8%) in the de-escalation group (n¼68) and in 10 patients (12.0%) in the control group (n¼83) (HR 0.72, 95% CI 0.26-1.98, p¼0.52) (Figure 1). The de-escalation group was at similar risk of BARC 2 bleeding events (5.9% vs. 8.4%, HR 0.69, 95% CI 0.20-2.36, p¼0.55) and ischemic events (2.9% vs. 4.8%, HR 0.60, 95% CI 0.11-3.32, p¼0.56) as the control group. There was one early definite stent thrombosis (ST) in the control group (day 19) and 1 possible ST (sudden cardiovascular death) in the de-escalation group (day 86), despite prasugrel treatment and in a background of high on- treatment platelet reactivity. CONCLUSION PFT-guided DAPT de-escalation strategy could be a safe and effective strategy in ACS patients with BVS implantation. The achieved level of platelet inhibition may be of particular importance in BVS-treated patients and further dedicated studies in larger cohorts of patients are needed to investigate upcoming BVS devices and concomitant DAPT strategies. CATEGORIES CORONARY: Acute Coronary Syndromes TCT-778 Impact of ticagrelor and aspirin versus clopidogrel and aspirin in symptomatic patients with peripheral arterial disease: Thrombus burden assessed by optical coherence tomography Mehmet Cilingiroglu, 1 Massoud Leesar, 2 Ismail Ates, 3 Deniz Mutlu, 4 Marc Feldman 5 1 Department of Cardiology, Arkansas Heart Hospital, Little Rock, Arkansas, United States; 2 University of Alabama-Birmingham, Birmingham, Alabama, United States; 3 Interventional Cardiologist, Antalya, Turkey; 4 Arkansas Heart Hospital, Department of Cardiology & Istanbul University, Cerrahpasa Faculty of Medicine, Department of Cardiology, Little Rock, Arkansas, United States; 5 UT Health San Antonio, San Antonio, Texas, United States BACKGROUND To compare OCT identified white thrombus decline, neointimal hyperplasia and clinical outcomes of patients treated with ticagrelor plus aspirin with those patients treated with clopidogrel plus aspirin after peripheral interventions. METHODS We enrolled 18 patients with superficial femoral artery disease and the presence of OCT-detected clot post-stent place- ment. Patients were randomized to 75 mg clopidogrel once daily for 1 month vs. 90 mg ticagrelor twice daily for 6 months, both in addition to 81 mg aspirin for 6 months. Clot volumes, ankle- brachial index (ABI), 6-minute walk test, and Rutherford classifi- cation were measured at baseline and 6-month follow-up. Neo- intimal hyperplasia and neovascularization were calculated at 6- month follow-up RESULTS N ¼ 11 patients were enrolled in the clopidogrel group and N ¼ 7 in the ticagrelor group. There was a significantly greater decrease in white thrombus in the ticagrelor group (median volume/ stent length (0.067 vs 0.014 mm3/mm, p ¼ 0.05)). No differences were found in % neointima (0.412 vs 0.536 mm3/mm, p ¼ 0.44) and neo- vascularization (28 vs 44, p ¼ 0.16). ABI and Rutherford classification were improved significantly after 6 months in the clopidogrel group, with no difference between groups at 6 months in ABI or Rutherford. Figure 1. The impact of two antiplatelet agents (Ticagrelor and Clo- pidogrel) to thrombus burden and neointimal hyperplasia is compared with using intravascular Optical Coherence Tomography in peripheral arterial disease. CONCLUSION In symptomatic patients with PAD, ticagrelor showed significant improvement relative to clopidogrel with respect to white thrombus burden decline. B310 JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY, VOL. 72, NO. 13, SUPPL B, 2018