Oral Antiplatelet Therapy Administered Upstream to Patients With NSTEMI

Objective: To describe from a noninterventional registry (Utilization of Ticagrelor in the Upstream Setting for Non-ST-Segment Elevation Acute Coronary Syndrome), the short-term ischemic and hemorrhagic outcomes in patients with non-ST elevation myocardial infarction (MI) are managed with a loading dose (LD) of a P2Y12 inhibitor (P2Y12i) given at least 4 hours before 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 non-ST elevation MI managed with an interventional strategy and loaded upstream (at least 4 h before diagnostic angiography) with oral P2Y12i therapy. Patients entered into the database were grouped into 1 of 4 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-day outcomes in the ticagrelor-consistent cohort. Results: A total of 3355 patients were enrolled, of whom 1087 had 30-day follow-up. The mean (±SD) age was 63.3 ± 12.5 years, and 62.6% were male. Thrombolysis in MI and Global Registry of Acute Coronary Events scores placed these patients in the intermediate risk range, and CRUSADE scores were in the moderate risk range. The LD in Utilization of Ticagrelor in the Upstream Setting for Non-ST-Segment Elevation Acute Coronary Syndrome was clopidogrel in 45.6%, ticagrelor in 53.6%, and prasugrel in 0.8%. The median upstream interval (LD 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%. Postangiography management was medical only in 32.3%, percutaneous coronary intervention in 59.4%, and coronary artery bypass grafting in 8.3%. Median length of stay was 2.7 days, and median time from angiography to coronary artery bypass grafting was 3.6 days. In-hospital mortality was 0.51%, and major bleeding (thrombolysis in MI) was 0.24%; the in-hospital major adverse cardiovascular events 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 1 P2Y12i in-hospital. On follow-up (93.2% response), 86.7% of patients reported taking ticagrelor as directed. Conclusions: Upstream loading of P2Y12i was associated with very low rates of bleeding and short length of stay in a large cohort of non-ST elevation MI (NSTEMI) patients managed invasively.