In:
Circulation: Cardiovascular Quality and Outcomes, Ovid Technologies (Wolters Kluwer Health), Vol. 6, No. 4 ( 2013-07), p. 470-478
Abstract:
To evaluate the previously reported excess of thromboembolic events during the 30 days after the end of study (EOS) visit when participants transitioned from blinded therapy to open-label vitamin K antagonist. Methods and Results— At the EOS visit, open-label vitamin K antagonist was recommended, and the international normalized ratio (INR) was not to be measured until 3 days later to preserve blinding. We analyzed transition strategies, clinical outcomes, and INR values. Event rates are per 100 patient-years. A total of 9248 (65%) participants were taking study drug at EOS, and, between days 3 and 30, an excess of stroke and systemic embolic events were observed in participants assigned to rivaroxaban (rivaroxaban 22 events, event rate 6.42; warfarin 6 events, event rate 1.73; hazard ratio, 3.72; 95% confidence interval, 1.51–9.16; P =0.0044). No INR values were reported for ≈5% of participants transitioned to warfarin. By 30 days after EOS, 83% of the warfarin group and 52% of the rivaroxaban group had ≥1 therapeutic INR value. Median time to first therapeutic INR was 3 days in the warfarin group and 13 days in the rivaroxaban group. Conclusions— The excess of events at EOS was likely because of a period of inadequate anticoagulation in rivaroxaban participants switched to vitamin K antagonist therapy. If transition from rivaroxaban to vitamin K antagonist is needed, timely monitoring and careful dosing should be used to ensure consistent and adequate anticoagulation.
Type of Medium:
Online Resource
ISSN:
1941-7713
,
1941-7705
DOI:
10.1161/CIRCOUTCOMES.113.000132
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2013
detail.hit.zdb_id:
2453882-6
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