Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a subgroup analysis of the ARISTOTLE trial. Lancet Neurol. 2012;11:503 511. 405. Hohnloser SH, Hijazi Z, Thomas L, Alexander JH, Amerena J, Hanna M, Keltai M, Lanas F, Lopes RD, Lopez-Sendon J, Granger CB, Wallentin L. Efficacy of apixaban when compared with warfarin in relation to renal function in patients with atrial fibrillation: insights from theARISTOTLE trial. Eur Heart J. 2012;33:2821 2830. 406. Freeman JV, Zhu RP, Owens DK, Garber AM, Hutton DW, Go AS, Wang PJ, Turakhia MP. Cost-effectiveness of dabigatran compared with warfarin for stroke prevention in atrial fibrillation. Ann Intern Med. 2011;154:1 11. 407. Kamel H, Johnston SC, Easton JD, Kim AS. Cost-effectiveness of dabi- gatran compared with warfarin for stroke prevention in patients with atrial fibrillation and prior stroke or transient ischemic attack. Stroke. 2012;43:881 883. 408. Kansal AR, Sorensen SV, Gani R, Robinson P, Pan F, Plumb JM, Cowie MR. Cost-effectiveness of dabigatran etexilate for the prevention of stroke and systemic embolism in UK patients with atrial fibrillation. Heart. 2012;98:573 578. 409. Shah SV, Gage BF. Cost-effectiveness of dabigatran for stroke prophy- laxis in atrial fibrillation. Circulation. 2011;123:2562 2570. 410. Krauel K, Hackbarth C, Furll B, Greinacher A. Heparin-induced throm- bocytopenia: in vitro studies on the interaction of dabigatran, rivaroxa- ban, and low-sulfated heparin, with platelet factor 4 and anti-PF4/heparin antibodies. Blood. 2012;119:1248 1255. 411. Chatterjee S, Sardar P, Biondi-Zoccai G, Kumbhani DJ. New oral anticoagulants and the risk of intracranial hemorrhage: traditional and bayesian meta-analysis and mixed treatment comparison of random- ized trials of new oral anticoagulants in atrial fibrillation. JAMA Neurol. 2013;70:1486 1490. 412. 