Severe Renal Impairment and Stroke Prevention in Atrial Fibrillation

Abstract

The prevalence of atrial fibrillation (AF) in end-stage renal failure is high, with an increased risk of stroke among these patients with AF compared with the AF population without severe renal impairment. Many trials have shown the net clinical benefit of oral anticoagulation therapy for primary and secondary prevention of stroke in patient populations with AF. However, current stroke risk stratification schemes are based on studies that have deliberately excluded patients with severe renal impairment. Indeed, there are no large randomized controlled trials that assess the real risk/benefit of full intensity anticoagulation in patients with severe renal impairment. Also, rates of major bleeding episodes in anticoagulated hemodialysis patients with AF are high. These data are influenced by the lack of appropriate monitoring, the difficulties in maintaining the international normalized ratio target (variable between the studies), and an inaccurate bleeding classification. Thus, the limited available data may be difficult to apply to such a heterogeneous patient population, characterized by both an increased risk of bleeding and a hypercoagulability state, as seen in the patient population with severe renal impairment.

Warfarin in Atrial Fibrillation Patients with Moderate Chronic Kidney Disease

“…Sixty-one percent of INR measurements were between 2.0 and 3.0, 25% were below this range, and 76% were within the range of 1.8 to 3.2. The randomized trial was terminated at the first interim analysis, after a mean follow-up of 1.1 year, due to the clear superiority of adjusted-dose warfarin (8).…”

“…Anticoagulation with adjusted-dose warfarin reduces the risk of stroke in patients with nonvalvular atrial fibrillation by about two-thirds, based on consistent results of several randomized trials (4), but its efficacy in CKD patients with atrial fibrillation has not been specifically established. In hemodialysis patients with atrial fibrillation (excluded from participation in randomized trials to date), recent observational studies have challenged the value of warfarin anticoagulation (5-7), leading to doubts about whether results of randomized trials can be reliably extrapolated to CKD patients (8).…”

2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS

“…Wiąże się ono ze zwiększoną umiewww.kardiologiapolska.pl ralnością wśród pacjentów dializowanych [417]. Nie przeprowadzono żadnych randomizowanych prób klinicznych, w których oceniono by OAC u pacjentów leczonych hemodializami [418] ani kontrolowanych prób klinicznych stosowania NOAC u pacjentów z ciężką CKD (CrCl < 25-30 ml/min) [318][319][320][321]. Stosowanie warfaryny wiązało się z neutralnym lub zwiększonym ryzykiem udaru mózgu w analizach baz danych obejmujących pacjentów dializowanych [419][420][421], w tym w analizie populacyjnej przeprowadzonej w Kanadzie (skorygowany HR udaru mózgu 1,14; 95% CI 0,78-1,67; skorygowany HR krwawienia 1,44; 95% CI 1,13-1,85) [422].…”

2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS

“…417 AF is associated with increased mortality in patients on dialysis. 417 There are no randomized trials assessing OAC in haemodialysis patients, 418 and no controlled trials of NOACs in patients with severe CKD (CrCl ,25 -30 mL/min). 318 -321 Warfarin use was associated either with a neutral or increased risk of stroke in database analyses of patients on dialysis, 419 -421 including a population-based analysis in Canada (adjusted HR for stroke 1.14; 95% CI 0.78 -1.67, adjusted HR for bleeding 1.44; 95% CI 1.13 -1.85).…”