A Multicenter Retrospective Evaluation of Direct Oral Anticoagulants for the Treatment of Heparin-Induced Thrombocytopenia.

INTRODUCTION: Direct oral anticoagulants (DOACs) represent an off-label but potential alternative to traditional therapies for heparin-induced thrombocytopenia (HIT). OBJECTIVE: The objective of this study was to evaluate the efficacy and safety of DOACs in patients with a diagnosis of laboratory-confirmed HIT. METHODS: A multicenter retrospective cohort study of adult patients with HIT treated with apixaban, rivaroxaban, or dabigatran between 1 January 2013 and 1 January 2020 was performed. Patients with an intermediate or high pre-test probability for HIT and a positive antiplatelet factor 4/heparin complex assay, latex immunoturbidimetric assay, or serotonin release assay were included for analysis. The primary outcome was the composite of newly diagnosed venous or arterial thromboembolism, gangrene, or severe limb ischemia requiring amputation at 3 months following DOAC initiation. This study was approved by local institutional review boards, and the requirement for informed consent was waived. RESULTS: A total of 77 patients from four health systems were included. The median 4Ts score was 5 (interquartile range 4.5-6), and 38 patients (49.4%) had a diagnosis of HIT with thrombosis. The most frequently used DOAC was apixaban (n = 51), followed by rivaroxaban (n = 24) and dabigatran (n = 2). In total, 63 (81.8%) patients received parenteral non-heparin anticoagulation prior to DOAC initiation. Nine patients (11.7%) experienced the primary outcome of HIT-related thrombotic events. Of the 14 patients who exclusively received DOAC therapy, none experienced the primary outcome. Major bleeding occurred in five (6.5%) patients. CONCLUSION: In this retrospective cohort study, DOACs were associated with rates of thrombotic and hemorrhagic events similar to those with other therapies currently used in the treatment of HIT.

Outcomes Associated With Resuming Direct Oral Anticoagulant Therapy Following Admission for a Gastrointestinal Bleed.

BACKGROUND: Although direct oral anticoagulants (DOACs) carry a lower bleeding risk compared with warfarin, gastrointestinal bleeds (GIB) are a known complication. There are limited data observing outcomes associated with resuming DOACs following a GIB. OBJECTIVE: The purpose of this study was to evaluate practice patterns and clinical outcomes of patients admitted with an index GIB while receiving DOAC therapy. METHODS: This retrospective, single-system study included adult patients receiving DOAC therapy prior to admission and hospitalized with an index GIB between January 1, 2013, and October 31, 2018. Patient exclusion criteria were a history of immune thrombocytopenia purpura or inflammatory bowel disease; discharge to hospice; leaving against medical advice; or death during hospitalization. The primary objective was 90-day readmission for a recurrent GIB. RESULTS: There were 57 patients included for analysis; 37 patients had DOAC therapy held >7 days, 18 patients resumed DOAC therapy within 7 days, and 2 patients switched to warfarin. The majority of patients received rivaroxaban (59.6%) prior to admission for atrial fibrillation (71.9%), were admitted with a major GIB (66.7%), and required a blood transfusion (61.4%). The rates of recurrent GIB were 2.5% (n = 1) and 5.6% (n = 1) for those who had their DOAC held and resumed, respectively (P = 0.83). Mortality within 12 months of discharge occurred in 4 patients (10.8%) who had their DOAC held and 4 patients (22.2%) who resumed DOAC therapy (P = 0.28). CONCLUSION AND RELEVANCE: Resuming anticoagulation within 7 days of admission for an index GIB was not associated with a recurrent GIB within 90 days of discharge.

Medication utilization evaluation of dabigatran and rivaroxaban within a large, multi-center health system.

OBJECTIVE: The objective of this medication utilization evaluation (MUE) was to determine the appropriateness of dabigatran and rivaroxaban while also reviewing outcomes for safety and effectiveness within a large, multi-center health system. METHODS: A retrospective chart review was performed using the system's electronic medical record. A data inquiry was requested and generated for dabigatran usage from July 28, 2011 through July 28, 2012 and for rivaroxaban from March 1, 2012 to July 31, 2012 at eight health system hospitals. All patients receiving at least one dose were eligible for inclusion in the MUE. RESULTS: For dabigatran, 78 of 390 unique patient encounters were analyzed (20%). All 62 rivaroxaban encounters were included in the analysis. Dabigatran was used for appropriate indications in 94% of encounters and 82% for rivaroxaban. Based on indication and renal function, 87% of dabigatran patients and 92% of rivaroxaban patients received correct dosing. For patients transitioning to or from another anticoagulant, appropriate transitions occurred in 44% of dabigatran transitions and 48% of rivaroxaban transitions. At discharge, 83% of dabigatran and 86% of rivaroxaban therapy was continued. There were no reported strokes or systemic embolism with dabigatran, but one reported deep vein thrombosis occurred during hospitalization with rivaroxaban therapy. Documented bleeds in 5% of dabigatran and 3% of rivaroxaban patients. Patient education was documented for 37% of dabigatran and 26% of rivaroxaban patients receiving therapeutic anticoagulation. CONCLUSION: This MUE revealed the appropriate use of dabigatran and rivaroxaban therapy with few safety outcomes within a large, multi-center health system.