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Direct acting non-Vitamin K antagonist oral anticoagulants (NOAC) are characterized by a fixed dosing regimen. Despite the potential for relative underdosing due to large distribution volumes, dose adjustments for patients with high body mass index (BMI) are not recommended. Since efficacy and safety data in obese patients are scarce, we evaluated the impact of BMI on clinical outcomes in daily care patients treated with NOAC for stroke prevention in atrial fibrillation or venous thromboembolism. Using prospectively collected data from a non-interventional registry, cardiovascular (CV), major bleeding events (MB) and all-cause mortality were evaluated according to BMI classes. All outcome events were centrally adjudicated using standard scientific definitions. Between November 1st 2011 and December 31st 2016, 3432 patients were enrolled into the registry (61.3% rivaroxaban; 20% apixaban; 10.1% dabigatran, 8.6% edoxaban; mean follow-up 998.1 ± 542.9 days; median 1004 days). With increasing BMI (range 13.7-57.2 kg/m 2 ), the proportion of patients receiving standard (vs. reduced) NOAC dose increased from 64.7% (underweight) to 78.9% (obesity). Although obese patients had more cardiovascular risk factors compared to normal weight patients, on-treatment rates of clinical outcomes (CV, MB, all-cause-mortality) were lowest in overweight and obese patients. In a large set of real-life NOAC recipients we found no indication that high BMI is associated with inferior NOAC effectiveness or safety, which is in line with recent epidemiological data of a "BMI paradox" that indicates a somewhat protective effect of higher BMI regarding unfavourable outcomes also in patients receiving fixed dose NOAC anticoagulation without dose adjustment for higher BMI., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aims: Vernakalant is a newly developed antiarrhythmic drug against atrial fibrillation (AF). However, its electrophysiological actions on human myocardium are unknown., Methods and Results: Action potentials (APs) and ion currents were recorded in right atrial trabeculae and cardiomyocytes from patients in sinus rhythm (SR) and chronic AF. Vernakalant prolonged early repolarization in SR and AF, but late only in AF. AP amplitude (APA) and dV/dtmax were reduced in a concentration- and frequency-dependent manner with IC50 < 10 µM at >3 Hz. Effective refractory period was increased more than action potential duration (APD) in SR and AF. INa was blocked with IC50s of 95 and 84 µM for SR and AF, respectively (0.5 Hz). Vernakalant did not reduce outward potassium currents compared with time-matched controls. However, area under the current-time curve was reduced due to acceleration of current decline with IC50s of 19 and 12 µM for SR and AF, respectively. Vernakalant had less effect on APD than the IKr blocker E-4031, blocked IK,ACh, and had a small inhibitory effect on IK1 at 30 µM. L-Type Ca(2+) currents (SR) were reduced with IC50 of 84 µM., Conclusion: Rate-dependent block of Na(+) channels represents the main antiarrhythmic mechanism of vernakalant in the fibrillating atrium. Open channel block of early transient outward currents and IK,ACh could also contribute.