Toward More Personalized Management of Device-Detected Atrial Fibrillation

This Viewpoint discusses the need to individualize the management of subclinical atrial fibrillation according to burden (among other factors) by modeling stroke risk.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Cardiovascular- and Bleeding-Related Hospitalization Rates With Edoxaban Versus Warfarin in Patients With Atrial Fibrillation Based on Results of the ENGAGE AF–TIMI 48 Trial

Background

The ENGAGE AF–TIMI 48 trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation–Thrombolysis in Myocardial Infarction 48) demonstrated noninferiority of once-daily 60 mg (30 mg dose-reduced) edoxaban compared with warfarin for prevention of stroke/systemic embolism in patients with atrial fibrillation. No previous analysis has explored the impact of treatment with edoxaban versus warfarin on rates of hospitalizations.

Methods

Detailed healthcare resource utilization data from ENGAGE AF–TIMI 48 for the 14 024 randomized patients who received at least one dose of study drug were used to compare the rates of bleeding- and cardiovascular-related hospitalizations for edoxaban versus warfarin. Hospitalization rates were calculated for each treatment group, and relative rates were estimated using Poisson regression. The influence of patient characteristics on the impact of edoxaban versus warfarin was evaluated through the inclusion of interaction terms.

Results

The overall rate of cardiovascular- or bleeding-related hospitalization was significantly lower for edoxaban than warfarin (relative rate [RR], 0.91 [95% CI, 0.85–0.97], P =0.003). Rates of hospitalizations for cardiovascular reasons (RR, 0.91 [95% CI, 0.85–0.97], P =0.004), stroke (RR, 0.80 [95% CI, 0.72–0.88], P <0.0001), and for each stroke subtype (ischemic: RR, 0.89 [95% CI, 0.81–0.99], P =0.03; hemorrhagic: RR, 0.60 [95% CI, 0.54–0.68], P <0.0001) were also lower for edoxaban. Notably, significantly greater reductions with edoxaban versus warfarin were seen for ischemic stroke–related hospitalizations in vitamin K antagonist naive patients and patients with CHADS 2 scores 4 to 6, previous stroke or transient ischemic attack, age ≥75, and no previous coronary artery disease. For nonstroke bleeding–related hospitalizations, greater reductions with edoxaban were seen in vitamin K antagonist naive patients, patients with CHADS 2 scores 4 to 6, and patients with moderate renal dysfunction.

Conclusions

Edoxaban 60 mg (30 mg dose-reduced) was associated with a significantly lower overall rate of cardiovascular- or bleeding-related hospitalization and significant reductions in the subcategories of cardiovascular-related, stroke-related, bleed-related, and nonstroke cardiovascular–related hospitalizations, when compared with warfarin. These results suggest the potential for cost offsets with edoxaban, with even greater reductions in higher-risk patients.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT00781391

Anticoagulation control in different ethnic groups receiving vitamin K antagonist therapy for stroke prevention in atrial fibrillation

BACKGROUND

Efficacy and safety of vitamin K antagonists (VKAs) is optimised in atrial fibrillation (AF) patients when the International Normalised Ratio (INR) is 2.0-3.0. Anticoagulation control comparing different ethnic groups is limited, although epidemiological studies suggest poorer INR control in non-white cohorts.

METHODS

VKA control was assessed retrospectively by time-in-the-therapeutic range (TTR) (Rosendaal method) and percentage INR-in-range (PINRR) in 991 White, Afro-Caribbean and South-Asian AF patients [overall mean (SD) age 71.6 (9.4) years; 55% male; mean (SD) CHA₂DS₂-VASc score 3.4 (1.6)] over a median (IQR) follow-up of 5.2 (3.2-7.0) years.

RESULTS

Compared to Whites, mean (SD) TTR and PINRR were significantly lower in South-Asians [TTR 67.9% vs. 60.5%; PINRR 58.8% vs. 51.6%, respectively] and Afro-Caribbeans [TTR 67.9% vs. 61.3%; PINRR 58.8% vs. 53.1%, respectively], despite similar INR monitoring intensity. Logistic regression revealed non-white ethnicity [OR 2.62; 95% Confidence Interval [CI] (1.67-4.10) and OR 3.47 (1.44-8.34)] and anaemia [OR 1.65 (1.00-2.70) and OR 6.27 (1.89-20.94)] as independent predictors of both TTR and PINRR < 70%, respectively. At follow-up, 329 (33.2%) patients experienced ≥1 major adverse clinical event. Cardiovascular hospitalisation was significantly higher among South-Asians (32.3%) compared to the Whites and Afro-Caribbeans (21.3% vs 25.6% respectively).

CONCLUSIONS

Ethnic disparities in quality of anticoagulation control are evident, with South-Asians and Afro-Caribbeans having poorer control compared to Whites, despite similar intensity INR monitoring. Non-white ethnicity remained the strongest independent predictor of poor TTR and PINRR. Interventions to improve anticoagulation control need to be implemented, particularly targeting ethnic minority patients.

The Admit-AF risk score: A clinical risk score for predicting hospital admissions in patients with atrial fibrillation

Aims

To develop and externally validate a risk score for all-cause hospital admissions in patients with atrial fibrillation.

Methods and results

We used a prospective cohort of 2387 patients with established atrial fibrillation as derivation cohort. Independent risk factors were selected from a broad range of variables using the least absolute shrinkage and selection operator method fit to a Cox model. The risk score was validated in a separate prospective cohort of 1300 atrial fibrillation patients. The incidence of all-cause hospital admission was 19.1 per 100 person-years in the derivation cohort and it was 26.1 per 100 person-years in the validation cohort. The most important predictors for admission were age (75–79 years: adjusted hazard ratio (aHR), 1.34; 95% confidence interval (CI), 1.01–1.78; 80–84 years: aHR, 1.50; 95% CI, 1.11–2.03; ≥85 years: aHR, 1.88; 95% CI, 1.36–2.62), prior pulmonary vein isolation (aHR, 0.72; 95% CI, 0.58–0.88), hypertension (aHR, 1.16; 95% CI, 0.99–1.36), diabetes (aHR, 1.38; 95% CI, 1.17–1.62), coronary heart disease (aHR, 1.17; 95% CI, 1.02–1.36), prior stroke/transient ischaemic attack (aHR, 1.26; 95% CI, 1.18–1.47), heart failure (aHR, 1.19; 95% CI, 1.03–1.39), peripheral artery disease (aHR, 1.35; 95% CI, 1.08–1.67), cancer (aHR, 1.33; 95% CI, 1.12–1.57), renal failure (aHR, 1.17; 95% CI, 0.99–1.37) and previous falls (aHR, 1.40; 95% CI, 1.13–1.74). A risk score with these variables was well calibrated, and achieved a C-index of 0.64 in the derivation and 0.59 in the validation cohort.

Conclusions

Multiple risk factors were associated with hospital admissions in atrial fibrillation patients. This prediction tool selects high-risk patients who may benefit from preventive interventions.

Apixaban: An Update of the Evidence for Its Place in the Prevention of Stroke in Patients with Atrial Fibrillation

Oral anticoagulant therapy for stroke prevention in atrial fibrillation patients has been remarkably changed by the introduction of non-vitamin k oral anticoagulants (NOAC). Apixaban was the third NOAC introduced to clinical practice. Aim was to outline the current evidence for Apixaban in stroke prevention in atrial fibrillation patients in the randomized trials and real-world data. Apixaban has been shown to be superior to warfarin in preventing stroke and systemic embolism and causes significantly less major bleeding based on large randomized trials. These data are confirmed in real-world studies. Apixaban has been shown to be safe and effective in atrial fibrillation patients in acute coronary syndrome or undergoing PCI in combination with a P2Y₁₂ inhibitor. Regarding expanded use of apixaban also in valvular heart disease patients, there is still missing knowledge in relation to the safety and efficacy of apixaban which is being addressed by ongoing randomized clinical trials.

Reasons for hospitalization and risk of mortality in patients with atrial fibrillation treated with dabigatran or warfarin in the Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY) trial

AIMS

Hospitalizations are common among patients with atrial fibrillation. This article aimed to analyse the causes and consequences of hospitalizations occurring during the Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY) trial.

METHODS AND RESULTS

The RE-LY database was used to evaluate predictors of hospitalization using multivariate regression modelling. The relationship between hospitalization and subsequent major adverse cardiac events was evaluated in a time dependent Cox proportional-hazard modelling. Of the 18 113 patients in RE-LY, 7200 (39.8%) were hospitalized at least once during a mean follow-up of 2 years. First hospitalization rates were 2312 (39.5%) for dabigatran etexilate (DE) 110, 2430 (41.6%) for DE 150, and 42.6% (N = 2458) for warfarin. Hospitalization was associated with post-discharge death [absolute event rate 9.1% vs. 2.2%; adjusted hazard ratio (HR) 3.6, 95% confidence interval (CI) 3.2-4.0, P < 0.0001], vascular death (adjusted HR 2.9, 95% CI 2.5-3.3, P < 0.0001), and sudden cardiac death (adjusted HR 2.3; 95% CI 1.8-2.9, P < 0.0001). Cardiovascular hospitalization was also associated with an increased risk of post-discharge death (adjusted HR 2.8, 95% CI 2.5-3.2, P < 0.0001), vascular death (adjusted HR 2.8, 95% CI 2.4-3.2, P < 0.0001), and sudden cardiac death (adjusted HR 2.1, 95% CI 1.6-2.7, P < 0.0001) compared with patients not hospitalized for any cardiovascular reason.

CONCLUSION

Hospitalizations are associated an increased risk of with death and cardiovascular death in patients with atrial fibrillation.

Thromboembolic risk and effect of oral anticoagulation according to atrial fibrillation patterns: A systematic review and meta-analysis

Oral anticoagulation (OAC) is recommended in both paroxysmal atrial fibrillation (pxAF) and nonparoxysmal AF (non-pxAF), but disagreement exists in classes of recommendation. Data on incidence/rate of stroke in pxAF are conflicting, and OAC is often underused in this population. The objectives of the meta-analysis were to investigate different impact on outcomes of pxAF and non-pxAF, with and without OAC. Two reviewers searched for prospective studies on risk of stroke and systemic embolism (SE) in pxAF and non-pxAF, with and without OAC. Quality of evidence was assessed according to GRADE approach. Stroke combined with SE was the main outcome. Meta-regression was performed to evaluate OAC effect on stroke and SE incidence rate. We identified 18 studies. For a total of 239 528 patient-years of follow-up. The incidence rate of stroke/SE was 1.6% (95% confidence interval [CI]: 1.3%-2.0%) in pxAF and 2.3% (95% CI: 2.0%-2.7%) in non-pxAF. Paroxysmal AF was associated with a lower risk of overall thromboembolic (TE) events (risk ratio: 0.72, 95% CI: 0.65-0.80, P < 0.00001) compared with non-pxAF. In both groups, the annual rate of TE events decreased as proportion of patients treated with OAC increased. Non-pxAF showed a reduction from 3.7% to 1.7% and pxAF from 2.5% to 1.2%. Major bleeding rates did not differ among groups. Stroke/SE risk is significantly lower, although clinically meaningful, in pxAF. OAC consistently reduces TE event rates across any AF pattern. As a whole, these data provide the evidence to warrant OAC irrespective of the AF pattern in most (virtually all) patients.

Apixaban to prevent stroke in patients with atrial fibrillation: a review

Atrial fibrillation is a common, costly and morbid cardiovascular arrhythmia. Stroke prevention remains the mainstay of treatment for atrial fibrillation, and the recent advent of novel oral anticoagulants with direct factor IIa or factor Xa inhibition has significantly revolutionized this aspect of treatment for atrial fibrillation patients. This review focuses on the tolerability and efficacy of apixaban and tackles the generalizability of the findings with apixaban to broader patient populations than those primarily enrolled in the clinical trials, drawing from the AVERROES and ARISTOTLE trials and their subsequent secondary analyses. Taken together, findings from these trials show that apixaban is superior to warfarin in preventing stroke with a lower risk of major bleeding in the general population of patients with atrial fibrillation as well as in several key high-risk patient subgroups.

How and When to Screen for Atrial Fibrillation after Stroke: Insights from Insertable Cardiac Monitoring Devices

The introduction of insertable cardiac monitoring devices has dramatically altered our understanding of the role of intermittent atrial fibrillation in cryptogenic stroke. In this narrative review we discuss the incidence, timing and relationship between atrial fibrillation and cryptogenic stroke, how to select patients for monitoring and the value and limitations of different monitoring strategies. We also discuss the role of empirical anticoagulation, and atrial fibrillation burden as a means of tailoring anticoagulation in patients at high risk of bleeding.

Stroke Event Rates and the Optimal Antithrombotic Choice of Patients With Paroxysmal Atrial Fibrillation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The risks of stroke or systemic embolism and major bleeding are considered similar between paroxysmal and sustained atrial fibrillation (AF), and warfarin has demonstrated superior efficacy to aspirin, irrespective of the AF type. However, with the advent of novel oral anticoagulants (NOACs) and antiplatelet agents, the optimal antithrombotic prophylaxis for paroxysmal AF remains unclear.We searched Medline, Embase, CENTRAL, and China Biology Medicine up to October week 1, 2015. Randomized controlled trials of AF patients assigned to NOACs, warfarin, or antiplatelets, with reports of outcomes stratified by the AF type, were included. A fixed-effects model was used if no statistically significant heterogeneity was indicated; otherwise, a random-effects model was used.Six studies of 69,990 nonvalvular AF patients with ≥1 risk factor for stroke were included. Postantithrombotic treatment, paroxysmal AF patients showed lower risks of stroke (risk ratio [RR], 0.72; 95% confidence interval [CI], 0.59-0.87), stroke or systemic embolism (RR, 0.74; 95% CI, 0.63-0.86), and all-cause mortality (RR, 0.75; 95% CI, 0.67-0.83), while the major bleeding risk was comparable (RR, 0.96; 95% CI, 0.85-1.08). We were unable to detect the superiority of anticoagulation over antiplatelets for paroxysmal AF (RR, 0.72; 95% CI, 0.43-1.23), while it was more effective than antiplatelets for sustained AF (RR, 0.42; 95% CI, 0.33-0.54). NOACs showed superior efficacy over warfarin and trended to show reduced major bleeding irrespective of the AF type.The AF type is a predictor for thromboembolism, and might be helpful in stroke risk stratification model in combination with other risk factors. With the appearance of novel anticoagulant and antiplatelet agents, the best antithrombotic choice for paroxysmal AF needs further exploration.

Non-vitamin K antagonist oral anticoagulants: new choices for patient management in atrial fibrillation

Atrial fibrillation (AF) is a significant problem for the aging population and remains a major factor underlying stroke risk. Warfarin anticoagulation has been proven effective for stroke prevention in AF, but can be difficult to manage and requires frequent monitoring. The non-vitamin K antagonist oral anticoagulants (NOACs) have been shown to be as effective as warfarin for stroke prevention in nonvalvular AF (NVAF) and are associated with a reduced risk of bleeding compared with warfarin. Dabigatran, rivaroxaban, apixaban, and edoxaban have been approved in the USA for reducing the risk of stroke in patients with NVAF. In this article, AF risk assessment is discussed and NOAC phase III clinical trials for the prevention of stroke and systemic embolic events are reviewed. Further, differences in stroke and bleeding outcomes between NOACs are highlighted, the use of NOACs for cardioversion and special patient populations is discussed, and management considerations for patients with AF are reviewed.

Preserving Cognitive Function in Patients with Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and is associated with significant morbidity and mortality. Its prevalence increases with increasing age, and is one of the leading causes of thromboembolism, including ischemic stroke. The prevalence of cognitive dysfunction also increases with increasing age. Although several studies have shown a strong correlation between AF and cognitive dysfunction in patients with and without overt stroke, a direct causative link has yet to be established. Rhythm vs rate control and anticoagulation regimens have been extensively investigated, particularly with the introduction of the novel anticoagulants. With catheter ablation becoming more prevalent for the management of AF and the ongoing development of various new energy sources and catheters, an additional thromboembolism risk is introduced. As cognitive dysfunction decreases the patient's ability to self-care and manage a complex disease such as AF, this increases the burden to our healthcare system. Therefore as the prevalence of AF increases in the general population, it becomes more imperative that we strive to optimize our methods to preserve cognitive function. This review gives an overview of the current evidence behind the association of AF with cognitive dysfunction, and discusses the most up-to-date medical and procedural treatment strategies available for decreasing thromboembolism associated with AF and its treatment, which may lead to preserving cognitive function.