Antiplatelet Therapy and Adverse Hematologic Events During Heart Mate II Support

Abstract

Background — Hematologic adverse events are common during continuous flow left ventricular assist device support; yet, their relation to antiplatelet therapy, including aspirin (ASA) dosing, is uncertain. Methods and Results— A single-center retrospective review of all patients supported by a continuous flow left ventricular assist device (Heart Mate II) from June 2006 to November 2014 was conducted. Patients were categorized into 3 groups: (1) ASA 81 mg+dipyridamole 75 mg daily (n=26) with a target international normalized ratio (INR) of 2 to 3 from June 2006 to August 2009; (2) ASA 81 mg daily (n=18) from September 2009 to August 2011 with a target INR of 1.5 to 2; and (3) ASA 325 mg daily from September 2011 to November 2014 with a target INR of 2 to 3 (n=70). Hemorrhagic and thrombotic outcomes were retrieved ≤365 days after implantation. Cumulative survival free from adverse events was calculated using Kaplan–Meier curves and Cox proportional hazard ratios were generated. Hemorrhagic events occurred in 6 patients on ASA 81 mg+dipyridamole (26%; 0.42 events per patient year; mean INR at event, 2.2), 4 patients on ASA 81 mg (22%; 0.38 events per patient year; mean INR at event, 2.0), and in 38 patients on ASA 325 mg (54%; 1.4 events per patient year; mean INR at event, 2.2); P =0.004. Patients on ASA 325 mg had a higher adjusted hazard ratio of 2.9 (95% confidence interval, 1.2–7.0 versus ASA 81 mg+dipyridamole; P =0.02) and 3.4 (95% confidence interval, 1.2–9.5 versus ASA 81 mg; P =0.02) for hemorrhagic events. Thrombotic events rates were not different between groups. Conclusions— High-dose ASA in Heart Mate II patients treated concomitantly with warfarin is associated with an increased hazard of bleeding but does not reduce thrombotic events.

Platelet activation is a preoperative risk factor for the development of thromboembolic complications in patients with continuous‐flow left ventricular assist device

“…Furthermore, our study indicates that different ASA dose (HM2 and HM3: 100 mg/day vs. HVAD: 300 mg/day) was not a major determinant for the occurrence of thromboembolic complications. Our findings are consistent with previous reports and recent mechanistic studies that questioned the role of ASA in modulating platelet response in the setting of cf‐LVAD therapy . Moreover, our results further extend the 2‐year endpoint of the EU TRACE study providing clinical evidences that the biochemical pathway of SMPA and the associated platelet prothrombotic profile are at least minimally modulated by ASA therapy in LVAD patients.…”

Continuous-Flow Left Ventricular Assist Device Survival Improves With Multidisciplinary Approach

“…B Systematic training and credentialing of ancillary staff at three competency levels (basic/advanced/ expert) (Supplemental Fig 2). Furthermore, we changed aspirin dosing from 325 mg/d to 81 mg/d based on prior experience [23,25].…”

Anticoagulation management following left ventricular assist device implantation is similar across all provider strategies†

“…Although protocols are necessary for standardization and improvements in care, there will always be a need for clinical judgement. There is a growing body of literature describing either reduced INR goals with aspirin or reduction of dose of aspirin alone in the reduction of bleeding risks with the HM II [18,19]. However, the INR is inversely related to thrombotic events outside of hospital care for patients with LVADs with an INR <2.0 [20].…”