Meta-analysis of the influence of chronic kidney disease on the risk of thromboembolism among patients with nonvalvular atrial fibrillation

Chronic kidney disease (CKD) and atrial fibrillation (AF) frequently coexist. However, the extent to which CKD increases the risk of thromboembolism in patients with nonvalvular AF and the benefits of anticoagulation in this group remain unclear. We addressed the role of CKD in the prediction of thromboembolic events and the impact of anticoagulation using a meta-analysis method. Data sources included MEDLINE, EMBASE, and Cochrane (from inception to January 2014). Three independent reviewers selected studies. Descriptive and quantitative information was extracted from each selected study and a random-effects meta-analysis was performed. After screening 962 search results, 19 studies were considered eligible. Among patients with AF, the presence of CKD resulted in an increased risk of thromboembolism (hazard ratio [HR] 1.46, 95% confidence interval [CI] 1.20 to 1.76, p = 0.0001), particularly in case of end-stage CKD (HR 1.83, 95% CI 1.56 to 2.14, p <0.00001). Warfarin decreased the incidence of thromboembolic events in patients with non-end-stage CKD (HR 0.39, 95% CI 0.18 to 0.86, p <0.00001). Recent data on novel oral anticoagulants suggested a higher efficacy of these agents compared with warfarin (HR 0.80, 95% CI 0.66 to 0.96, p = 0.02) and aspirin (HR 0.32, 95% CI 0.19 to 0.55, p <0.0001) in treating non-end-stage CKD. In conclusion, the presence of CKD in patients with AF is associated with an almost 50% increased thromboembolic risk, which can be effectively decreased with appropriate antithrombotic therapy. Further prospective studies are needed to better evaluate the interest of anticoagulation in patients with severe CKD.

Two-year clinical outcome from the Iberian registry patients after left atrial appendage closure

AIMS: The aim of this study was to observe the percentage of thromboembolic and haemorrhagic events over a 2-year follow-up in patients with non-valvular atrial fibrillation (NVAF) undergoing closure of the left atrial appendage (LAA) with an occlusion device. Observed events and CHADS2 (congestive heart failure, hypertension, age, diabetes, stroke history), CHA2DS2-VASc (also adding: vascular disease and sex) and HAS-BLED (hypertension, abnormal liver/renal function, stroke history, bleeding predisposition, labile international normalised ratios, elderly, drugs/alcohol use)-predicted events were compared. METHODS: LAA closure with an occlusion device was performed in 167 NVAF patients contraindicated for oral anticoagulants and recruited from 12 hospitals between 2009 and 2013. At least two transoesophageal echocardiograms were performed in the first 6 months postimplantation. Antithrombotics included clopidogrel and aspirin. Patients were monitored for death, stroke, major and relevant bleeding and hospitalisation for concomitant conditions. Mean age was 74.68±8.58, median follow-up was 24 months, 5.38% had intraoperative complications and implantation was successful in 94.6% of subjects. Mortality during follow-up was 10.8%, mostly (9.5%) non-cardiac related. Bleeding occurred in 10.1% of subjects, 5.7% major and 4.4% minor though relevant, and 4.4% suffered stroke. Major bleeding and stroke/transient ischaemic attack events within 2 years (annual event rates, 290 patients/year) were less frequent than expected from CHADS2 (2.4% vs 9.6%), CHA2DS2-VASc (2.4% vs 8.3%) and HAS-BLED (3.1% vs 6.6%) risk scores (p<0.001, p=0.003, p=0.047, respectively). CONCLUSIONS: LAA closure with an occlusion device in patients contraindicated for oral anticoagulants is a therapeutic option associated with fewer thromboembolic and haemorrhagic events than expected from risk scores, particularly in the second year postimplantation.