Pharmacist-Managed International Normalized Ratio Patient Self-Testing Is Associated with Increased Time in Therapeutic Range in Patients with Left Ventricular Assist Devices at an Academic Medical Center
ABSTRACT Patients with left ventricular assist devices (LVADs) are at increased risk of bleeding and thrombotic complications making warfarin therapy particularly challenging. Patient self-testing (PST) using point-of-care international normalized ratio (INR) devices has shown favorable outcomes in other populations, but the use of PST in LVAD patients has not been well described. The purpose of this study was to evaluate the effectiveness of pharmacist-managed INR PST versus usual care (UC) in patients with LVADs at a single center. We performed a retrospective cohort study of adult patients (in a 1:4 ratio PST versus UC) implanted with an LVAD (HeartMate II or HVAD) treated with warfarin from January 1, 2007, to January 31, 2013. We reviewed all INRs and bleeding/thrombotic events in LVAD patients whose anticoagulation was managed by clinical pharmacists via INR PST versus UC and calculated a percent time in therapeutic range (%TTR) by Rosendaal method. Fifty-five patients were studied. Demographic data were generally similar between the cohorts. Mean %TTR was higher in the PST cohort versus UC (44.4% vs. 30.6%, p = 0.026). There was no difference in the rate per patient-year of bleeding (0.23 vs. 0.33, p = 0.55) or thrombotic events (0.12 vs. 0.13, p = 0.88). Pharmacist-managed INR PST is associated with an increased %TTR in patients with LVADs.
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ABSTRACT: Pharmacists are uniquely qualified to play essential roles in the clinical implementation of pharmacogenomics. However, specific responsibilities and resources needed for these roles have not been defined. We describe roles for pharmacists that emerged in the clinical implementation of genotype-guided clopidogrel therapy in the University of Florida Health Personalized Medicine Program, summarize preliminary program results, and discuss education, training, and resources needed to support such programs. Planning for University of Florida Health Personalized Medicine Program began in summer 2011 under leadership of a pharmacist, with clinical launch in June 2012 of a clopidogrel-CYP2C19 pilot project aimed at tailoring antiplatelet therapies for patients undergoing percutaneous coronary intervention and stent placement. More than 1000 patients were genotyped in the pilot project in year 1. Essential pharmacist roles and responsibilities that developed and/or emerged required expertise in pharmacy informatics (development of clinical decision support in the electronic medical record), medication safety, medication-use policies and processes, development of group and individual educational strategies, literature analysis, drug information, database management, patient care in targeted areas, logistical issues in genetic testing and follow-up, research and ethical issues, and clinical precepting. In the first 2 years of the program (1 year planning and 1 year postimplementation), a total of 14 different pharmacists were directly and indirectly involved, with effort levels ranging from a few hours per month, to 25–30% effort for the director and associate director, to nearly full-time for residents. Clinical pharmacists are well positioned to implement clinical pharmacogenomics programs, with expertise in pharmacokinetics, pharmacogenomics, informatics, and patient care. Education, training, and practice-based resources are needed to support these roles and to facilitate the development of financially sustainable pharmacist-led clinical pharmacogenomics practice models.Pharmacotherapy 10/2014; 34(10). DOI:10.1002/phar.1481 · 2.66 Impact Factor
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ABSTRACT: Left ventricular assist devices (LVADs) have increased the survival of patients with advanced heart failure fourfold. Despite these advances, significant bleeding and thrombotic complications occur. Hemorrhage requiring surgery has been reported in up to 30 % of adults and 50 % of children after LVAD placement. LVAD thrombosis and embolic stroke lead to significant long-term morbidity. Adults are treated with antithrombotic therapy to prevent thrombotic complications, but the amount and intensity of treatment differs between institutions. The goal international normalized ratio for warfarin therapy varies from 1.5 to 3.0. Some physicians manage adult LVAD patients without antiplatelet medication, whereas other adults are treated with aspirin as a single agent or combined with dipyridamole. In contrast, physicians typically manage children with LVADs using the Edmonton Anticoagulation and Platelet Inhibition Protocol, a detailed algorithm for anticoagulation and antiplatelet treatment modified based on thromboelastography results. LVAD implantation causes consumption of coagulation proteins, activation of fibrinolysis, and loss of high molecular weight von Willebrand protein multimers. How these changes in the coagulation system influence the risk of hemorrhage and initiation of thrombosis is unknown. Prospective, controlled studies are needed to determine the antithrombotic regimen that most effectively balances bleeding and thrombosis in LVAD patients.Journal of Thrombosis and Thrombolysis 12/2014; 39(3). DOI:10.1007/s11239-014-1162-6 · 2.17 Impact Factor
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ABSTRACT: Background Left ventricular assist devices (LVADs) have dramatically increased the survival of adults with end-stage systolic heart failure. However, rates of bleeding and thromboembolism remain high.Objectives We completed a systematic review to evaluate outcomes of adults with LVADs treated with various anticoagulant and antiplatelet strategies.Methods Databases were searched using the terms “assist device,” “thrombosis,” and “anticoagulant” or “platelet aggregation inhibitor” with appropriate synonyms, device names and manufacturers.Results and Conclusions Of 977 manuscripts, 24 articles met the inclusion criteria of adults with implanted LVADs where clinical outcomes were defined based on anticoagulant and/or antiplatelet regimen. Most studies reported treatment with unfractionated heparin post-operatively which was transitioned to a vitamin K antagonist (VKA). Goal INR varied between 1.5-3.5. Antiplatelet regimens ranged from no treatment to dual therapy. Definition of major bleeding differed between trials and incidence varied between 0% and 58%. The available evidence could not demonstrate a clear benefit of aspirin compared with VKA therapy alone [stroke RR 1.02 (95% CI 0.49-2.1)]. There was a suggestion that treatment with aspirin and dipyridamole decreased the risk of thromboembolism compared to aspirin [RR 0.50 (0.36-0.68)], but the comparison is limited by differences in demographics, devices, and INR goals among studies. Additionally, most studies did not blind to outcomes thus contributing to an increased risk for bias. Clinical equipoise exists as to the most appropriate antithrombotic therapy in LVAD patients. Randomization between regimens within a prospective trial is needed to define the treatment regimen that minimizes both bleeding and thrombotic complicationsThis article is protected by copyright. All rights reserved.Journal of Thrombosis and Haemostasis 04/2015; 13(6). DOI:10.1111/jth.12948 · 5.72 Impact Factor