Anticoagulation in Atrial Fibrillation Jesse Tran R2

Class I recommendations In patients with nonvalvular AF, calculate CHA2DS2-VASc CHA2DS2-VASc of 2 or greater, oral anticoagulation recommended. Wafarin with INR 2-3, dabigatran, rivaroxaban, or apixaban. In patients with A flutter, anticoagulation is recommended as above.

Class IIa, IIb In patient with nonvalvular AF and CHA2DS2-VASc of 0, no need for anticoagulation. CHA2DS2-VASc of 1, can consider anticoagulation or ASA. Patients undergoing PCI, BMS considered to minimize duration of dual anti platelet therapy. Following coronary revascularization in pts with A fib and a CHA2DS2-VASc of 2 or greater, can use plavix with oral anticoagulants, but without ASA.

Class III Direct thrombin inh and factor Xa inh are not recommended in patents with AF and end-stage CKD or HD. Lack of evidence Direct thrombin inh, dabigatran, should not be used in pts with AF and mechanical heart valve.

Bleeding Risk HAS-BLED: HTN - sbp >160, Abnormal renal/liver function, Stroke, Bleeding hx or predisposition, Labile INR, Elderly - >65, Drugs/alcohol. Score of greater than or equal to 3 indicates patients at higher risk of bleeding.

Antiplatelet Therapy ASA has been shown to be beneficial in both primary and secondary prevention of stroke, though inferior to other methods of anticoagulation. Plavix + ASA vs Warfarin was compared in the ACTIVE-W trial. Ended early due to inferiority between these two groups in pts with CHADS2 = 2. Plavix + ASA proved to be superior to ASA alone in ACTIVE-A trial.

Warfarin Vitamin K antagonist ARR 2.7% per year, NNT 37 in one year to prevent 1 stroke, NNT of 12 in pts with prior stroke. Risk of stroke in pts with warfarin 1.66% annually Risk of intracranial hemorrhage was significantly increased in those with oral anticoagulants. Numerous drug interactions, affects on diet, need for frequent monitoring.

Direct Thrombin Inhibitor Renally excreted, lower dose approved in pts with CrCl 15-30 mL/min. Compared with warfarin in RE-LY trial Dabigatran at 150mg BID superior to warfarin in this study, 110mg BID non inferior for primary outcomes of stroke and systemic embolism. Lower rates of intracranial bleeding, but higher rates of GI bleeding in the 150mg BID group.

Factor Xa Inhibitor Single daily dose for reduction of stroke and systemic embolism in patients with nonvalvular AF. Renal excretion ROCKET AF trial which showed non inferiority. Major bleeding was similar between warfarin and rivaroxaban, but had less fatal bleeding and less ICH.

Factor Xa Inhibitors Hepatic elimination ARISTOTLE trial - showed significant reduction in overall stroke, emboli, and major bleeding events. Fewer ICH with similar GI bleeding complications.

Benefits of new anticoagulation agents Fewer drug-drug interactions No dietary effects Less risk of ICH No need for frequent monitoring No reversal agents, though short half life

Dose Adjustments