Case in Point: Would You Anticoagulate this Patient?

You are called to the hospital to see a 78-year-old patient with diabetes mellitus, coronary artery disease, hypertension, congestive heart failure and end-stage renal disease (ESRD) on hemodialysis who was undergoing a declotting procedure of his fistula and developed atrial fibrillation (AF) during anesthesia induction. You order an echocardiogram that shows LVEF 35% to 40% with moderate concentric hypertrophy and global hypokinesis. You are asked to offer recommendations on pharmacologic management of the patient, particularly on the use of oral anticoagulation.

You calculate the patient’s CHA₂DS₂-Vasc score, which comes to 6.

Please click here for answer and next question.

Answer: C. It depends

Granted, there is controversy about whether patients on dialysis should even be anticoagulated at all. But given this patient’s very high risk of thromboembolism, you recommend anticoagulation and start to write “Initiate warfarin with INR goal 2-3” in your recommendations as you have been told many times that the direct oral anticoagulants (DOACs) should be used with caution in patients on hemodialysis and with severely reduced eGFR. In addition, many of these patients were not included in the large randomized controlled clinical trials of these agents.

Before you sign your note, however, you do a quick literature search.

Please click here for answer and discussion.

Answer: A. Apixaban (Eliquis)

You find data on a study published in Circulation in July on use of apixaban in ESRD. As apixaban has a low degree of renal clearance, it does not appear to have the same detrimental effects as dabigatran or rivaroxaban in ESRD.

The observational study from a retrospective cohort of 25 523 Medicare beneficiaries (46% women, mean age ~68 years (matched AF patients with ESRD receiving apixaban and warfarin 1:3). After matching, apixaban was associated with a lower risk of major bleeding (HR 0.72, 95% CI 0.59-0.87; P<.001) without a significant difference in the risk for stroke/systemic embolism (HR 0.88, 95% CI 0.69-1.12; P=0.29). The 5-mg dose appears to be associated with lower rates of stroke and systemic embolism as well as death compared to the 2.5 mg apixaban dose or warfarin.

Obviously, this study lacks the rigorous quality of a randomized controlled trial (which, by the way, is forthcoming and called RENAL-AF). But, it does provide us with some “real world” data on the potential safety of apixaban compared to warfarin in renal disease.

So, the next time, you are about to write “start warfarin” in autopilot mode, consider whether you should change that recommendation to “Start apixaban 5 mg po bid” instead.

Reference: Siontis KC, Zhang X, Eckard A, et al. Outcomes associated with apixaban use in end-stage kidney disease patients with atrial fibrillation in the United States. 24 Jul 2018Circulation. 2018;0:CIRCULATIONAHA.118.035418.