[Effect of platelet reactivity on clinical events in patients using bivalirudin in selective percutaneous coronary...

Objective: To investigate the effect of platelet reactivity and other clinical factors on the postoperative 1-year adverse clinical events in patients who underwent selective percutaneous coronary intervention (PCI) anticoagulated with bivalirudin. Methods: This is a multicenter, retrospective and observational study, enrolling 632 patients at high risk of bleeding adjudicated by operators who underwent selective PCI anticoagulated with bivalirudin and had preoperative thrombelastography (TEG) test results in Fuwai Hospital, Northern Theater General Hospital and Xinxiang Central Hospital between January 2017 and August 2018. Platelet reactivity was tested by TEG and adenosine-induced maximal amplitude (MA_ADP) was recorded. According to MA_ADP patients were divided into three groups: low on-treatment platelet reactivity (LTPR) group (MA_ADP<31 mm, n=229), normal on-treatment platelet reactivity (NTPR) group (31 mm≤MA_ADP≤47 mm, n=207) and high on-treatment platelet reactivity (HTPR) group (MA_ADP>47 mm, n=196). The endpoints consisted of major adverse cardiovascular and cerebrovascular events (MACCE) and bleeding events. The definition of MACCE was the composite of all-cause mortality, myocardial infarction, intrastent thrombosis, stroke and revascularization. Bleeding events were defined by bleeding academic research consortium (BARC) type 2, 3 and 5 bleeding. Using multivariate Cox regression to analyze the factors of MACCE and bleeding events in patients underwent selective PCI anticoagulated with bivalirudin. Results: A total of 632 patients were finally enrolled in the study with age of (68.3±10.0) years and there were 423 (66.9%) males. All of 632 patients finished one-year follow-up, and 48 (7.6%) patients occurred MACCE and 11 (1.7%) patients occurred bleeding events. There was not statistically significant difference in the incidence of MACCE (8.3% (19/229) vs. 6.3% (13/207) vs.8.2% (16/196), P=0.68) and bleeding events (1.8% (4/229) vs. 2.9% (6/207) vs. 0.5% (1/196), P=0.17) in LTPR, NTPR and HTPR group. Multivariate Cox regression showed that HTPR was not the independent factor of MACCE (HR=1.25, 95%CI 0.67-2.30, P=0.49), and the history of peripheral vessel disease was the independent risk factor of MACCE (HR=2.47, 95%CI 1.19-5.11, P=0.02). LTPR was not the independent factor of bleeding events (HR=1.35, 95%CI 0.39-4.66, P=0.64), and the independent factors of bleeding events were history of peripheral vessel disease (HR=3.95, 95%CI 1.03-15.22, P=0.05) and hemoglobin (HR=0.96, 95%CI 0.93-0.99, P=0.01). Conclusions: In patients undergoing selective PCI anticoagulated with bivalirudin, there is no significant association between platelet reactivity and postoperative 1-year MACCE or bleeding events. History of peripheral vessel disease is an independent risk factor of MACCE, and history of peripheral vessel disease and decreased hemoglobin are independent risk factors of bleeding events.