ORAL ANTIPLATELET THERAPY ADMINISTERED UPSTREAM TO PATIENTS WITH NSTEMI.

Objective To describe from a non-interventional registry the short-term ischemic and hemorrhagic outcomes in patients with NSTEMI managed with a loading dose of a P2Y12 inhibitor (P2Y12i) given at least four hours prior to diagnostic angiography and delineation of coronary anatomy. Prior data on the effects of such "upstream loading" have been inconsistent. Methods In 53 US hospitals, we evaluated the in-hospital care and outcomes of patients with confirmed NSTEMI managed with an interventional strategy and loaded upstream (at least four hours before diagnostic angiography) with P2Y12 inhibitor therapy. Patients entered into the database were grouped into one of four cohorts for analysis: (1) overall cohort, (2) thienopyridine (clopidogrel or prasugrel) load, (3) ticagrelor load, and (4) ticagrelor-consistent. The fourth cohort is a subset of cohort 3 that received ticagrelor throughout the index hospital stay and at discharge. We evaluated in-hospital clinical course and ischemic and bleeding outcomes in all patients, and also 30-d outcomes in the ticagrelor-consistent cohort. Results A total of 3,355 patients were enrolled, of whom 1,087 had 30-day follow-up. The mean (+/-SD) age was 63.3+/-12.5 y and 62.6% were male. TIMI and GRACE scores placed these patients in the intermediate risk range and CRUSADE scores were in the moderate risk range. The loading dose in UPSTREAM was clopidogrel in 45.6%, ticagrelor in 53.6%, and prasugrel in 0.8%. The median upstream interval (loading dose to angiography) was 17:27 hours and did not change appreciably over the course of the data collection period (2/15 - 10/19). Access was radial in 48.6% and femoral in 51.4%. Post-angiography management was medical only in 32.3%, PCI in 59.4%, and CABG in 8.3%. Median LOS was 2.7d, and median time from angiography to CABG was 3.6d. In-hospital mortality was 0.51% and major bleeding (TIMI) was 0.24%; the in-hospital MACE rate was 0.7% and stent thrombosis occurred in 0.18%. No significant differences were seen between the ticagrelor and clopidogrel cohorts in hospital, but 16% received more than one P2Y12i in-hospital. On follow-up (93.2% response), 86.7% of patients reported taking ticagrelor as directed. Conclusion Upstream loading of P2Y12 inhibitors was associated with very low rates of bleeding and short LOS in a large cohort of NSTEMI patients managed invasively.