Nonvitamin K-dependent oral anticoagulants (NOACs) in chronic kidney disease patients with atrial fibrillation

Appropriateness of prescribing profiles and intake adherence to non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: analysis of a retrospective longitudinal study using real-world data from Northern Portugal (AF-React Study)

OBJECTIVES

This study aimed to assess the appropriateness of prescribing profiles and intake adherence to non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF).

DESIGN

Retrospective longitudinal study.

SETTING

The study was conducted in the Regional Health Administration of Northern Portugal.

PARTICIPANTS

The authors selected a database of 21 854 patients with prescriptions for NOACs between January 2016 and December 2018 and were classified with AF until December 2018.

OUTCOME MEASURES

The appropriate dosage of NOAC for patients with AF divided into three categories: contraindicated, inconsistent and consistent, based on the 2020 European Society of Cardiology guidelines for AF.

RESULTS

Dabigatran had a lower percentage of guideline-consistent doses (n=1657, 50.1%) than other drugs such as rivaroxaban (n=4737, 81.6%), apixaban (n=3830, 78.7%) and edoxaban (n=436, 82.1%). Most patients with an inconsistent dose were prescribed a lower dose than recommended based on their glomerular filtration rate (GFR). Among patients younger than 75 years with GFR >60 mL/min, 59.8% (n=10 028) had an adequate GFR range, while 27.8% (n=7166) of GFR measurements from patients older than 75 years old and 29.4% (n=913) of GFR measurements from patients younger than 75 years with GFR <60 mL/min were within an adequate time range. Adherence to NOACs varied across different drugs, with 59.1% (n=540) adhering to edoxaban, 56.3% (n=5443) to rivaroxaban, 55.3% (n=3143) to dabigatran and 53.3% (n=4211) to apixaban.

CONCLUSIONS

Dabigatran had the lowest percentage of guideline-consistent doses. Patients younger than 75 years with GFR >60 mL/min had the highest percentage with an adequate GFR range, while other groups who require closer GFR monitoring had lower percentages within an adequate GFR range. Adherence to NOACs differed among different drugs, with greater adherence to treatment with edoxaban and less adherence to apixaban.

Survival benefits of oral anticoagulation therapy in acute kidney injury patients with atrial fibrillation: a retrospective study from the MIMIC-IV database

OBJECTIVE

To find out the effect of different oral anticoagulation therapies (OAC) on mortality rate in patients with acute kidney injury (AKI) and atrial fibrillation (AF).DesignA retrospective study.

SETTING

This study was conducted in the Medical Information Mart for Intensive Care IV database.

PARTICIPANTS

A total of 19 672 patients diagnosed with AKI.

MAIN OUTCOME MEASURES

Patients were categorised into three groups: (1) AF; (2) AKI and AF, OAC-; (3) AKI and AF, OAC+. The primary endpoint was 30-day mortality. Secondary endpoints were the length of stay (LOS) in the intensive care unit (ICU) and hospital. Propensity score matching (PSM) and Cox proportional hazards model adjusted confounding factors. Linear regression was applied to assess the associations between OAC treatment and LOS.

RESULTS

After PSM, 2042 pairs of AKI and AF patients were matched between the patients who received OAC and those without anticoagulant treatment. Cox regression analysis showed that, OAC significantly reduce 30-day mortality compared with non-OAC (HR 0.30; 95% CI 0.25 to 0.35; p<0.001). Linear regression analysis revealed that OAC prolong LOS in hospital (11.3 days vs 10.0 days; p=0.013) and ICU (4.9 days vs 4.4 days; p<0.001). OAC did not improve survival in patients with haemorrhage (HR 0.67; 95% CI 0.34 to 1.29; p=0.23). Novel OAC did not reduce mortality in acute-on-chronic renal injury (HR 2.03; 95% CI 1.09 to 3.78; p=0.025) patients compared with warfarin.

CONCLUSION

OAC administration was associated with improved short-term survival in AKI patients concomitant with AF.

New evidence of direct oral anticoagulation therapy on cardiac valve calcifications, renal preservation and inflammatory modulation

BACKGROUND

Rivaroxaban is a direct inhibitor of activated Factor X (FXa), an anti-inflammatory protein exerting a protective effect on the cardiac valve and vascular endothelium. We compare the effect of Warfarin and Rivaroxaban on inflammation biomarkers and their contribution to heart valve calcification progression and renal preservation in a population of atrial fibrillation (AF) patients with chronic kidney disease (CKD) stage 3b - 4.

METHODS

This was an observational, multicenter, prospective study enrolling 347 consecutive CKD stage 3b - 4 patients newly diagnosed with AF: 247 were treated with Rivaroxaban and 100 with Warfarin. Every 12 months, we measured creatinine levels and cardiac valve calcification via standard trans-thoracic echocardiogram, while plasma levels of inflammatory mediators were quantified by ELISA at baseline and after 24 months.

RESULTS

Over a follow-up of 24 months, long-term treatment with Rivaroxaban was associated with a significative reduction of cytokines. Patients treated with Rivaroxaban experienced a more frequent stabilization/regression of valve calcifications comparing with patients treated with Warfarin. Rivaroxaban use was related with an improvement in kidney function in 87.4% of patients, while in those treated with Warfarin was reported a worsening of renal clearance in 98% of cases. Patients taking Rivaroxaban experienced lower adverse events (3.2% vs 49%, p-value <0.001).

CONCLUSIONS

Our findings suggest that Rivaroxaban compared to Warfarin is associated with lower levels of serum markers of inflammation. The inhibition of FXa may exert an anti-inflammatory effect contributing to reduce the risk of cardiac valve calcification progression and worsening of renal function.

Impaired kidney function at ED admission: a comparison of bleeding complications of patients with different oral anticoagulants

Background

Up to a fourth of patients at emergency department (ED) presentation suffer from acute deterioration of renal function, which is an important risk factor for bleeding events in patients on oral anticoagulation therapy. We hypothesized that outcomes of patients, bleeding characteristics, therapy, and outcome differ between direct oral anticoagulants (DOACs) and vitamin-K antagonists (VKAs).

Methods

All anticoagulated patients older than 17 years with an impaired kidney function treated for an acute haemorrhage in a large Swiss university ED from 01.06.2012 to 01.07.2017 were included in this retrospective cohort study. Patient, treatment, and bleeding characteristics as well as outcomes (length of stay ED, intensive care unit and in-hospital admission, ED resource consumption, in-hospital mortality) were compared between patients on DOAC or VKA anticoagulant.

Results

In total, 158 patients on DOAC and 419 patients on VKA with acute bleeding and impaired renal function were included. The renal function in patients on VKA was significantly worse compared to patients on DOAC (VKA: median 141 μmol/L vs. DOAC 132 μmol/L, p = 0.002). Patients on DOAC presented with a smaller number of intracranial bleeding compared to VKA (14.6% DOAC vs. 22.4% VKA, p = 0.036). DOAC patients needed more emergency endoscopies (15.8% DOAC vs, 9.1% VKA, p = 0.020) but less interventional emergency therapies to stop the bleeding (13.9% DOAC vs. 22.2% VKA, p = 0.027). Investigated outcomes did not differ significantly between the two groups.

Conclusions

DOAC patients were found to have a smaller proportional incidence of intracranial bleedings, needed more emergency endoscopies but less often interventional therapy compared to patients on VKA. Adapted treatment algorithms are a potential target to improve care in patients with DOAC.

Effects of rivaroxaban and warfarin on the risk of gastrointestinal bleeding and intracranial hemorrhage in patients with atrial fibrillation: Systematic review and meta-analysis

To assess the risk of gastrointestinal bleeding and intracranial hemorrhage in patients with atrial fibrillation (AF) after the use of rivaroxaban or warfarin. To investigate the effects of rivaroxaban and warfarin on gastrointestinal and intracranial hemorrhage in patients with AF, we searched PubMed, Embase, and Medline from the establishment of databases up to 2020. We finally included 38 observational studies involving 1 312 609 patients for the assessment of intracranial hemorrhage, and 33 observational studies involving 1 332 956 patients for the assessment of gastrointestinal bleeding. The rates of intracranial hemorrhage were 0.55% in the rivaroxaban group versus 0.91% in the warfarin group (OR 0.59; 95% CI 0.53-0.66; p < .00001, I2 = 78%). The rates of gastrointestinal bleeding were 2.63% in patients with rivaroxaban versus 2.48% in those with warfarin (OR 1.06; 95% CI 0.96-1.17; p < .00001, I2 = 94%). Rivaroxaban could significantly reduce the risk of intracranial hemorrhage in patients with AF than warfarin, but the risk of gastrointestinal bleeding remained controversy due to no statistical significant difference. Notably, a subgroup analysis demonstrated that patients in rivaroxaban group with severe chronic renal diseases or undergoing hemodialysis exposed to less gastrointestinal hemorrhage risk than the group from warfarin.

Managing Atrial Fibrillation in Patients With Heart Failure and Reduced Ejection Fraction: A Scientific Statement From the American Heart Association

Atrial fibrillation and heart failure with reduced ejection fraction are increasing in prevalence worldwide. Atrial fibrillation can precipitate and can be a consequence of heart failure with reduced ejection fraction and cardiomyopathy. Atrial fibrillation and heart failure, when present together, are associated with worse outcomes. Together, these 2 conditions increase the risk of stroke, requiring oral anticoagulation in many or left atrial appendage closure in some. Medical management for rate and rhythm control of atrial fibrillation in heart failure remain hampered by variable success, intolerance, and adverse effects. In multiple randomized clinical trials in recent years, catheter ablation for atrial fibrillation in patients with heart failure and reduced ejection fraction has shown superiority in improving survival, quality of life, and ventricular function and reducing heart failure hospitalizations compared with antiarrhythmic drugs and rate control therapies. This has resulted in a paradigm shift in management toward nonpharmacological rhythm control of atrial fibrillation in heart failure with reduced ejection fraction. The primary objective of this American Heart Association scientific statement is to review the available evidence on the epidemiology and pathophysiology of atrial fibrillation in relation to heart failure and to provide guidance on the latest advances in pharmacological and nonpharmacological management of atrial fibrillation in patients with heart failure and reduced ejection fraction. The writing committee's consensus on the implications for clinical practice, gaps in knowledge, and directions for future research are highlighted.

Use of Non-vitamin K Antagonist Oral Anticoagulants for Stroke Prevention across the Stroke Spectrum: Progress and Prospects

Multiple randomized controlled trials and many real-world evidence studies have consistently shown that non-vitamin K antagonist oral anticoagulants (NOACs) are preferable to vitamin K antagonists for thromboembolic stroke prevention in the majority of patients with atrial fibrillation (AF). However, their role in the management of patients with AF and comorbidities, as well as in other patient populations with a high risk of stroke, such as patients with prior embolic stroke of undetermined source (ESUS) and those with atherosclerosis, is less clear. There is now increasing evidence suggesting that NOACs have a beneficial effect in the prevention of stroke in patients with AF and comorbidities, such as renal impairment and diabetes. In addition, while studies investigating the efficacy and safety of NOACs for the prevention of secondary stroke in patients with a history of ESUS demonstrated neutral results, subanalyses suggested potential benefits in certain subgroups of patients with ESUS. One NOAC, rivaroxaban, has also recently been found to be effective in reducing the risk of stroke in patients with chronic cardiovascular disease including coronary artery disease and peripheral artery disease, further broadening the patient groups that may benefit from NOACs. In this article, we will review recent evidence for the use of NOACs across the stroke spectrum in detail, and discuss the progress and future prospects in the different stroke areas.

Factors associated with renal impairment in Chinese patients with non-valvular AF and without an established renal disease: a cross-sectional study

BACKGROUND

Renal impairment and atrial fibrillation (AF) often coexist. However, risk factors associated with renal impairment in AF patients have not been studied in a large population. Accordingly, this study investigated clinical factors associated with renal impairment in AF patients.

METHODS

From January 2012 to December 2016, 2,298 inpatients with non-valvular AF (NVAF) mainly for catheter ablation were enrolled in this cross-sectional study. Data collection included past medical history, echocardiography measurements, current medicine use and biochemical results. The estimated glomerular filtration rate (eGFR) was calculated using the abbreviated Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. Renal impairment was defined as a history of chronic kidney disease or an eGFR ≤90 ml/min/1.73 m². Multivariate logistic regression was conducted to evaluate the relationship between the factors screened and eGFR.

RESULTS

The mean eGFR was 88.6 ± 17.1 ml/min/1.73 m². The overall prevalence of renal impairment was 47.4%. Multivariate logistic regression showed that factors associated with renal impairment were age (OR: 1.12; 95% CI: 1.11-1.14), non-paroxysmal AF (OR: 1.28; 95% CI: 1.04-1.58), use of angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB) (OR: 1.58; 95% CI: 1.28-1.95), congestive heart failure (OR: 1.80; 95% CI: 1.05-3.07), left ventricular ejection fraction (LVEF) <50% (OR: 2.39; 95% CI: 1.34-4.28), and prior transient ischemic attack (TIA)/stroke/systematic embolism (SE) (OR: 2.69; 95% CI: 1.68-4.29).

CONCLUSIONS

Renal dysfunction is highly prevalent in Chinese NVAF patients and is significantly associated with older age, non-paroxysmal AF, use of ACEI/ARB, congestive heart failure, LVEF <50% and prior TIA/stroke/SE. Further studies on the mechanisms by which these risk factors affect renal function in NVAF patients need to be conducted.

Oral Anticoagulation for Atrial Fibrillation Thromboembolism Prophylaxis in the Chronic Kidney Disease Population: the State of the Art in 2019

Atrial fibrillation (AF) is the most common cardiac rhythm disturbance and is associated with increased risk of thromboembolism. Oral anticoagulants are effective at reducing rates of thromboembolism in patients with AF in the general population. Patients with AF and concurrent chronic kidney disease (CKD) have higher risk of thromboembolism and bleeding compared with patients with normal renal function. Among moderate CKD and end-stage renal disease (ESRD) patients on chronic dialysis, the use of oral anticoagulants is controversial. Use of warfarin, while beneficial in non-CKD patients, raises a number of concerns such as increased bleeding risk, labile anticoagulant effect, and calciphylaxis, especially in the ESRD population. The newer direct oral anticoagulant (DOAC) agents have demonstrated comparable efficacy and improved safety profiles compared with coumadin but are not as well studied in the CKD population. This review highlights the efficacy and safety of coumadin and the DOACs for thromboembolism prophylaxis in non-valvular AF patients with CKD.

Net clinical benefit of non-vitamin K antagonist oral anticoagulants in atrial fibrillation and chronic kidney disease: a trade-off analysis from four phase III clinical trials

Background

Atrial fibrillation (AF) is quite prevalent in patient with chronic kidney disease (CKD). This study mainly investigated the net clinical benefit (NCB) property of non-vitamin K antagonist oral anticoagulants (NOACs) versus warfarin in patients with AF and CKD by a pooled-analysis.

Methods

A comprehensive search of Medline, Embase, Cochrane Library and Clinical Trials.gov Website was performed for eligible randomized controlled trials (RCTs) reporting the efficacy and safety outcomes according to renal function of NOACs. Pre-specified outcomes and their number of patients needed to treat (NNT), including stroke/systemic embolism (SSE), major bleeding, and all-cause death, were evaluated using a random-effects model. NCB that balanced SSE and major bleeding was calculated using Singer's method.

Results

Four phase III clinical trials including 70,952 patients were enrolled, 45,265 (64%) with CKD, and 25,687 (36%) without CKD; 41,942 (59%) taking NOACs and 29,010 (41%) taking warfarin. Risks of SSE [relative risk (RR): 0.80, 95% confidence interval (CI): 0.73-0.88, P<0.01], major bleeding (RR: 0.79, 95% CI: 0.66-0.96, P=0.017), and all-cause death (RR: 0.91, 95% CI: 0.84-0.99, P=0.031) were significantly lower in CKD patients with NOACs than those with warfarin, accompanying with a high absolute risk reduction (NNT: 182 for SSE; 122 for major bleeding; 196 for all-cause death). While NOACs were not superior to warfarin on SSE, major bleeding, and all-cause death in patients without CKD, the NCB of NOACs versus warfarin was progressively increased with the deterioration of renal function (NCB: 0.72 for no CKD, 1.59 for mild CKD, 2.74 for moderate CKD). Sensitivity analyses did not significantly affect the primacy results.

Conclusions

NOACs, compared with warfarin, provide a better clinical profile on SSE, major bleeding, all-cause death, and NCB in CKD patients.

Anticoagulation in atrial fibrillation with heart failure

Heart failure (HF) and atrial fibrillation (AF) frequently coexist, and they can beget one another due to similar factors and shared pathophysiology. These pathophysiologic changes promote the episodes of AF, while they in turn predispose to the exacerbation of HF. In this review, we will discuss pathophysiological mechanisms shared by AF and HF. Patients with concomitant HF and AF are at a particularly high risk of thromboembolism, which contribute to even worse symptoms and poorer prognosis. Vitamin K antagonists (VKA) (warfarin) were the traditional medication in AF patients for the prevention of stroke, whereas the advance of novel non-VKA oral anticoagulants (NOACs) (dabigatran, apixaban, rivaroxaban, and edoxaban) is challenging these standard prescriptions. NOACs' potential advantages over warfarin, including fixed dosing regimens, wide therapeutic window, and more sustained anticoagulant response, promote clinicians to consider these novel agents in the first place. However, some data suggested patients with AF and HF may receive different therapeutic response than those with AF alone in anticoagulant treatment. Accordingly, we aim to assess the potential role of oral anticoagulants, especially NOACs, in the management of patients with concomitant AF and HF.

Cardiac valve calcification and use of anticoagulants: Preliminary observation of a potentially modifiable risk factor

AIMS

Direct oral anticoagulant (DOAC) has been recently introduced in the clinical practice. Rather than interfering with vitamin K-dependent posttranscriptional modification of various proteins, DOACs selectively inhibit factors involved in the coagulation cascade. In particular, in contrast with Warfarin, Rivaroxabn does not interfere with activation of matrix Gla Protein (MGP), a potent vascular calcification Inhibitor. We herein sought to investigate the impact of Rivaroxaban and Warfarin on cardiac valve calcifications in a cohort of moderate-to advanced CKD patients.

METHODS AND RESULTS

This is a multicenter, observational, retrospective, longitudinal study. Consecutive CKD stage 3b - 4 (according to KDIGO guidelines) patients from 8 cardiologic outpatient clinics were enrolled between May 2015 and October 2017. All patients received anticoagulation (100 Warfarin vs 247 Rivaroxaban) as part of their non-valvular atrial fibrillation management. Cardiac valve calcification was evaluated via standard trans-thoracic echocardiogram. 347 patients (mean age: 66 years; mean eGFR: 37 ml/min/1.73 m²) were studied. Over a mean follow-up period of 16 months, Rivaroxaban compared to Warfarin reduced both mitral and aortic valve calcifications (p < 0.001) independently of the degree of calcifications at baseline and potential confounders. Notably, Rivaroxaban use was also associated with a significant reduction in C reactive protein (CRP) (p < 0.001) during follow-up.

CONCLUSION

This study generates the hypothesis that the use of Rivaroxaban associates with a reduction of cardiac valve calcification deposition and progression as compared to Warfarin, in a cohort of CKD stage 3b-4 patients. Future endeavors are needed to confirm and to establish the mechanisms responsible for these findings.

Periprocedural Considerations for Anticoagulated Atrial Fibrillation Patients

Periprocedural patient instruction and coordination is an important piece in achieving safe outcomes for patients needing procedures and receiving anticoagulants for atrial fibrillation. Balancing the needs for anticoagulation versus bleeding during the procedure requires clinical reasoning and preparation. In this article, the current guidelines for use of anticoagulants with atrial fibrillation, the relevant pharmacology, and the use of standardized tools to quantify the risks of thrombus or bleeding in the procedures will be discussed. In addition, resources for examining the optimal practice for these case types will be provided. Perianesthesia health care providers are pivotal to lead relevant stakeholders in the perianesthesia setting work together to create protocols and individual plans of care for this patient population.

Cardiorenal Syndrome: An Overview

It is well established that a large number of patients with acute decompensated heart failure present with various degrees of heart and kidney dysfunction usually primary disease of heart or kidney often involve dysfunction or injury to the other. The term cardiorenal syndrome increasingly had been used without a consistent or well-accepted definition. To include the vast array of interrelated derangements and to stress the bidirectional nature of heart-kidney interactions, a new classification of the cardiorenal syndrome with 5 subtypes that reflect the pathophysiology, the time frame, and the nature of concomitant cardiac and renal dysfunction was proposed. Cardiorenal syndrome can generally be defined as a pathophysiological disorder of the heart and kidneys, in which acute or chronic dysfunction of one organ may induce acute or chronic dysfunction to the other. Although cardiorenal syndrome was usually referred to as acute kidney dysfunction following acute cardiac disease, it is now clearly established that impaired kidney function can have an adverse impact on cardiac function.

Trends and Variation in Oral Anticoagulant Choice in Patients with Atrial Fibrillation, 2010-2017

OBJECTIVE

Since 2010, several non-vitamin K antagonist oral anticoagulants (NOACs) have been brought to the U.S. market, yet little is known regarding their evolving adoption for prophylaxis of atrial fibrillation (AF)-related stroke. We examined temporal trends in choice of oral anticoagulants (OACs) among incident OAC users with AF and its association with patient demographic and clinical characteristics.

METHODS

We conducted a serial cross-sectional analysis of medical and pharmacy claims for commercial and Medicare Advantage enrollees in a large, private, U.S. health plan. We identified 112,187 adults with nonvalvular AF starting OACs between October 2010 and March 2017. Multivariable logistic regression was used to examine the associations of patient characteristics with prescription of NOACs versus warfarin. Multinomial logistic regression was used to test the associations of patient characteristics with choice among NOACs.

RESULTS

The prescription of NOACs has increased dramatically since their introduction in October 2010. In the first quarter of 2017 (2017Q1), 7502 patients started OACs, of whom 78.9% used NOACs and 21.1% warfarin. For NOACs, 3.8% used dabigatran, 25.0% rivaroxaban, and 50.1% apixaban. In multivariable analyses, factors associated with choice of NOACs versus warfarin included younger age, lower stroke or bleeding risk, fewer comorbidities, higher education level or household net worth, and prescription by cardiologists (all p<0.001). There was no sex difference in likelihood of filling NOACs versus warfarin in 2010Q4-2012, but women had higher odds of starting NOACs (odds ratio = 1.19; 95% confidence interval = 1.14-1.25) in 2015-2017Q1. Among NOAC users, the odds of apixaban prescription increased with age, female sex, stroke or bleeding risk, and comorbidities (all p<0.05).

CONCLUSION

NOAC prescriptions have increased substantially among incident OAC users with nonvalvular AF, predominantly driven by increased prescription of apixaban. Warfarin and apixaban were generally preferred for elderly patients, patients with higher stroke or bleeding risk, and patients with more comorbidities.

Safety and effectiveness of rivaroxaban and warfarin in moderate-to-advanced CKD: real world data

BACKGROUND

In recent years, novel anticoagulant drugs have been introduced in the clinical armamentarium and have progressively gained momentum. Although their use is increasing among CKD patients, some skepticism about their risk-benefit ratio still persists. We sought to investigate the safety and effectiveness of rivaroxaban in a cohort of moderate-to-advanced CKD patients.

METHODS

This observational, retrospective, longitudinal study involved 347 consecutive CKD stage 3b-4 (according to NKF-KDOQI guidelines) patients enrolled from 8 cardiac outpatient clinics between March 2015 and October 2017. All patients received anticoagulation (100 warfarin vs. 247 rivaroxaban) as part of their non-valvular atrial fibrillation management at the attending physician's discretion. Clinical effectiveness (defined as the occurrence of ischemic stroke, venous thromboembolism, or transient ischemic attack) and safety (intracranial hemorrhage, gastrointestinal or other bleeding) were assessed separately.

RESULTS

Over a mean follow-up period of 16 ± 0.3 months, 25 stroke episodes (15 hemorrhagic, and 10 ischemic) occurred in 24 warfarin treated patients vs. none in the rivaroxaban arm. There were 5 vs. 0 episodes of deep venous thrombosis and 8 vs. 2 major episodes of bleeding in the warfarin and rivaroxaban groups, respectively. In contrast, the proportion of minor episodes of bleeding was similar between groups.

CONCLUSION

Rivaroxaban seems a safe and effective therapeutic option in CKD stage 3b-4 patients. However, future randomized controlled trials are needed to definitively establish the role of rivaroxaban in CKD patients.

Predictors of Cardioembolic Stroke in Japanese Patients with Atrial Fibrillation in the Fushimi AF Registry

Background

Large-scale clinical trials have analyzed risk factors for any ischemic stroke in patients with atrial fibrillation (AF). However, the risk factors for cardioembolic stroke (CES), specifically, have not been reported. To clarify the risk factors for CES and clinically significant cardioembolic infarction, we examined the incidence of CES and larger infarct volume (IV) (> 30 mL) CES, employing the Fushimi AF Registry, a community-based prospective cohort of AF patients in the Fushimi ward, Kyoto, Japan.

Methods

A total of 4,182 Fushimi AF patients were enrolled from March 2011 to December 2014. The risk factors for CES were evaluated using multivariate analysis.

Results

Of 4,182 patients enrolled, 3,749 patients were observed for ≥1 year. During the follow-up period (mean duration, 979 ± 7.7 days), 91/3,749 patients experienced a CES (2.43%). Significant risk factors associated with CES were older age (odds ratio [OR], 1.31; 95% confidence interval [CI], 1.01–1.72; p = 0.046), low body weight (OR, 1.30; 95% CI, 1.03–1.65; p = 0.033), sustained AF (OR, 1.67; 95% CI, 1.05–2.71; p = 0.034), and previous stroke or transient ischemic attack (TIA) (OR, 1.94; 95% CI, 1.22–3.06; p = 0.004). Predictors of a large IV were chronic kidney disease (CKD) (OR, 2.08; 95% CI, 1.09–4.05; p = 0.027) and previous stroke/TIA (OR, 2.27; 95% CI, 1.19–4.24; p = 0.011).

Conclusions

In this population-based cohort of Japanese patients with AF, in addition to previous stroke/TIA and older age, sustained AF and low body weight emerged as risk factors for CES, as opposed to any stroke, which may have a different risk profile. Patients with CKD or previous stroke/TIA who developed cardioembolic infarction exhibited more advanced severity. There is a need for direct oral anticoagulants that can be used safely in patients with comorbid AF and CKD.

Role of uremic toxin indoxyl sulfate in the progression of cardiovascular disease

The prevalence of cardiovascular disease (CVD) among patients with chronic kidney disease (CKD) is relatively high. Deterioration of renal function in CKD leads to accumulation of indoxyl sulfate, a tryptophan metabolite produced by gut microbiota. It is acknowledged that indoxyl sulfate is capable to stimulate oxidative stress, which in turn contributes to the progression of vascular disorders and its resultant coronary artery disease. Recent research have demonstrated the adverse effects of indoxyl sulfate on the heart, together with the acceleration of vascular dysfunction, suggesting that indoxyl sulfate might contribute to high prevalence of CVD in CKD. The present mini review has focused on the potential mechanisms by which indoxyl sulfate exerts this pro-oxidant effects on the cardiovascular system. The action of indoxyl sulfate are related to multiple NADPH oxidase-mediated redox signaling pathways, which have been implicated in the pathophysiology of different forms of CVD, including chronic heart failure, arrhythmia, atherosclerotic vascular disease and coronary calcification. Future therapeutic options are discussed, including modulating gut microbial flora and blocking responsible pathophysiologic pathways.