Anticoagulation Therapy for Non-valvular Atrial Fibrillation: A Mini-Review

Decision model to evaluate the cost of clinical events associated with switching from apixaban to rivaroxaban among patients with non-valvular atrial fibrillation in the United States and Germany

AIMS

Direct-acting oral anticoagulants (DOACs) have emerged as the preferred treatment for nonvalvular atrial fibrillation (NVAF). However, evidence concerning the economic outcomes of DOAC switching remains limited. This study aimed to assess the economic outcomes of DOAC switching in the US and Germany, two countries with a high AF prevalence and DOAC utilization.

METHODS

A decision model was developed to assess the incidence and cost of stroke/systemic embolism (SE) and major bleeding (MB) associated with switching from apixaban to rivaroxaban in patients with NVAF. The model compared two scenarios: continuers (patients continuing apixaban) and switchers (patients switching from apixaban to rivaroxaban). Model inputs on clinical event rates were sourced from a published real-world study, cost inputs were from a standard costing database and published literature. The analysis was conducted over a 1-year time horizon from US Medicare fee-for-service and German public healthcare payer perspectives.

RESULTS

Over one year, 47,036 patients among a hypothetical plan size of 1,000,000 US Medicare fee-for-service members and 1,019,079 patients among the German adult population size of 70,107,122 were estimated to be treated for NVAF with apixaban. Switching all patients from apixaban to rivaroxaban resulted in 1,498 and 32,447 additional clinical events (stroke/SE and MB) and deaths in the US and Germany, respectively, compared to continuing with apixaban. This led to a total incremental cost of $17.3 million and €153 million from Medicare fee-for-service and German public healthcare perspectives, respectively.

LIMITATIONS

The incidence and hazard ratios of clinical events informing this analysis were based on a US commercial and Medicare Advantage population and may not be generalizable to other populations.

CONCLUSIONS

Switching from apixaban to rivaroxaban was associated with increased clinical events, deaths, and higher medical care costs, potentially representing a less favorable strategy economically compared to continuing apixaban among patients with NVAF.

Bridging the Gaps in Atrial Fibrillation Management in the Emergency Department

Atrial fibrillation (AF) frequently presents in emergency departments (EDs), contributing significantly to adverse cardiovascular outcomes. Despite established guidelines, ED management of AF often varies, revealing important gaps in care. This review addresses specific challenges in AF management for patients in the ED, including the nuances of rate versus rhythm control, the timing of anticoagulation initiation, and patient disposition. The updated 2024 European Society of Cardiology (ESC) guidelines advocate early rhythm control for select patients while recommending rate control for others; however, uncertainties persist, particularly regarding these strategies' long-term impact on outcomes. Stroke prevention through timely anticoagulation remains crucial, though the ideal timing, especially for new-onset AF, needs further research. Additionally, ED discharge protocols and follow-up care for AF patients are often inconsistent, leaving many without proper long-term management. Integration of emerging therapies, including direct oral anticoagulants and advanced antiarrhythmic drugs, shows potential but remains uneven across EDs. Innovative multidisciplinary models, such as "AF Heart Teams" and observation units, could enhance care but face practical challenges in implementation. This review underscores the need for targeted research to refine AF management, optimize discharge protocols, and incorporate novel therapies effectively. Standardizing ED care for AF could significantly reduce stroke risk, lower readmission rates, and improve overall patient outcomes.

Association of Body Mass Index with Echocardiographic Parameters and Incidence of Left Atrial Thrombus or Spontaneous Echo Contrast in Patients with Nonvalvular Atrial Fibrillation: A Cross-Sectional Study

Background

This article focuses on the effect of body mass index (BMI) on cardiac structure and function in cases with non-valvular atrial fibrillation (NVAF). Only a few articles have investigated the relationship between BMI and the incidence of left atrial thrombus (LAT) or spontaneous echo contrast (SEC) in cases with NVAF.

Methods

This single-center retrospective study was conducted at The First People's Hospital of Changzhou. A total of 282 patients who were diagnosed with NVAF and planned to undergo radiofrequency ablation from 2019 to 2022 were enrolled in this study. None of the patients received standardized anticoagulant therapy. The patients were divided into a normal weight group, an overweight group, and an obesity group based on their BMI. The differences in echocardiographic parameters and LAT/SEC incidences among the three groups were compared, and regression analysis was applied to determine the correlation between BMI and the occurrence rates of LAT/SEC. The generalized additive model (GAM) was used to clarify the dose-response association between BMI and LAT/SEC.

Results

Left atrial diameter (LAD), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), left ventricular ejection fraction (LVEF), right atrial diameter (RAD), and the incidences of LAT/SEC were statistically different among the three groups. Univariate and multivariate logistic regression analyses indicated that BMI was related to the incidences of LAT/SEC. For each 1-unit increase in BMI, the odds of LAT/SEC increased by 12% (odds ratio (OR): 1.12, 95% CI: 1.02, 1.24). A threshold nonlinear relationship was found using the GAM between BMI and the risk of LAT/SEC.

Conclusions

BMI significantly affects multiple echocardiographic parameters in patients with NVAF, and BMI is an independent risk factor for LAT/SEC in cases with NVAF.

Appropriateness of direct oral anticoagulant dosing in patients with atrial fibrillation at a tertiary care hospital in Thailand

Background

Appropriate dosing of direct oral anticoagulants (DOACs) has been associated with clinical efficacy and safety. Several studies have shown that DOAC dosing are often inconsistent with guideline recommendations. Little is known about this issue in Thailand. This study aimed to evaluate the appropriateness of DOAC dosing in Thai hospitalized patients with atrial fibrillation (AF).

Method

This was a retrospective descriptive study conducted on hospitalized patients at Rajavithi Hospital, a tertiary care hospital in Thailand. Inpatients diagnosed with AF and treated with DOACs between February 2021 and February 2023 were enrolled in the study. The appropriate dosing of DOACs was assessed according to the recommendation of the 2021 European Heart Rhythm Association Practical Guide on the Use of Non-Vitamin K Antagonist Oral Anticoagulants in Patients with Atrial Fibrillation (EHRA). Descriptive statistics were used to analyze the data; median (interquartile range) for continuous variables, and numbers and percentages for categorical variables.

Results

A total of 120 patients with AF were evaluated for dosing. The patients received rivaroxaban in 47 cases (39.2 %), apixaban in 32 cases (26.7 %), edoxaban in 31 cases (25.8 %), and dabigatran in 10 cases (8.3 %). Most of the patients were elderly, with a median age of 77.5 (68-84) years. Females were predominant (57.5 %). Our findings indicate that the prevalence of appropriate dosing of DOACs was 63.3 %. However, approximately one-third of patients received inappropriate dosing, with 24 (20.0 %) being overdosed, and 20 (16.7 %) being underdosed. The highest overdosing and underdosing rates were seen in dabigatran (90.0 %) and apixaban (21.9 %), respectively.

Conclusion

Inappropriate dosing of DOACs according to the 2021 EHRA recommendations was high in 36.7 %, with overdosing mostly occurring in 20.0 %. The high number of inappropriate dosing highlights the need for implementation of optimal strategies to select the appropriate dose of DOACs in Thai hospitalized patients with AF.

Assays for Monitoring Apixaban and Rivaroxaban in Emergency Settings, State-of-the-Art Routine Analysis, and Volumetric Absorptive Microsamples Deliver Discordant Results

Our aim was to compare the performance of complementary clinical laboratory approaches to monitoring exposure to apixaban and rivaroxaban, the most prescribed direct-acting oral anticoagulants (DOAC's): an automated commercial anti-Xa chromogenic assay suitable for emergency and pre-surgery testing and a laboratory-developed liquid chromatography-tandem mass spectrometry (LC-MS/MS) method employed for non-emergency analysis in plasma and in dried blood volumetric absorptive microsamples (VAMS) collectible by the patients in their homes. The full validation of the LC-MS/MS method was performed. Cross-validation of the methodologies was accomplished by processing 60 specimens collected for whole blood count and DOAC monitoring in a central clinical laboratory. For VAMS samples, dried plasma and whole blood calibrators were found to be suitable, and a cycle run for seven days could be implemented for rational and economic sample processing. The anti-Xa chromogrenic assay and the LC-MS/MS method delivered discordant plasma analyte concentrations. Moreover, the lack of agreement between plasma and VAMS concentrations was observed. Clinical laboratories must be aware of the differences between the performance of apixaban and rivaroxaban LC-MS/MS and anti-Xa assays. Hematocrit must always be measured along with VAMS samples to obtain accurate results.

Management of cerebral amyloid angiopathy and atrial fibrillation: We are still far from precision medicine

The use of anticoagulation therapy could prove to be controversial when trying to balance ischemic stroke and intracranial bleeding risks in patients with concurrent cerebral amyloid angiopathy (CAA) and atrial fibrillation (AF). In fact, CAA is an age-related cerebral vasculopathy that predisposes patients to intracerebral hemorrhage. Nevertheless, many AF patients require oral systemic dose-adjusted warfarin, direct oral anticoagulants (such as factor Xa inhibitors) or direct thrombin inhibitors to control often associated with cardioembolic stroke risk. The prevalence of both CAA and AF is expected to rise, due to the aging of the population. This clinical dilemma is becoming increasingly common. In patients with coexisting AF and CAA, the risks/benefits profile of anticoagulant therapy must be assessed for each patient individually due to the lack of a clear-cut consensus with regard to its risks in scientific literature. This review aims to provide an overview of the management of patients with concomitant AF and CAA and proposes the implementation of a risk-based decision-making algorithm.

Role of a National Health Service Electronic Prescriptions Database in the Detection of Prescribing and Dispensing Issues and Adherence Evaluation of Direct Oral Anticoagulants

BACKGROUND

Anticoagulation therapy plays a crucial role in the management of atrial fibrillation (AF) by significantly reducing the risk of stroke. Direct oral anticoagulants (DOAC) became preferred over warfarin due to their superior safety and efficacy profile. Assessing adherence to anticoagulation therapy is necessary in clinical practice for optimising patient outcomes and treatment efficacy, thus emphasising its significance.

METHODS

A retrospective study utilised the Latvian National Health Service reimbursement prescriptions database, covering prescriptions for AF and flutter from January 2012 to December 2022. The proportion of days covered method was selected for adherence assessment, categorising it into three groups: (1) below 80%, (2) between 80% and 90%, and (3) above 90%.

RESULTS

A total of 1,646,648 prescriptions were analysed. Dabigatran prescriptions started declining after 2020, coinciding with a decrease in warfarin prescriptions since 2018. The total adherence levels to DOAC therapy were 69.4%. Only 44.2% of users achieved an adherence level exceeding 80%. The rate of paper prescriptions decreased from 98.5% in 2017 to 1.3% in 2022. Additionally, the utilisation of international non-proprietary names reached 79.7% in 2022. Specifically, 16.7% of patients selected a single pharmacy, whereas 27.7% visited one or two pharmacies. Meanwhile, other patients obtained medicines from multiple pharmacies.

CONCLUSIONS

The total adherence level to DOAC therapy is evaluated as low and there was no significant difference in age, gender, or "switcher" status among adherence groups. Physicians' prescribing habits have changed over a decade.

The Association between Coagulation and Atrial Fibrillation

The existing literature highlights the presence of numerous coagulation factors and markers. Elevated levels of coagulation factors are associated with both existing and newly diagnosed cases of atrial fibrillation (AF). However, this article summarizes the role of coagulation in the pathogenesis of AF, which includes fibrinogen and fibrin, prothrombin, thrombomodulin, soluble urokinase plasminogen activator receptor, von Willebrand factor, P-selectin, D-dimer, plasminogen activator inhibitor-1, and platelet activation. Coagulation irregularities play a significant role in the pathogenesis of AF.

Application of computed tomographic angiography and echocardiography in predicting left atrial appendage thrombosis in patients with non-valvular atrial fibrillation

AIM

We aimed to explore the application of computed tomographic angiography (CTA) and echocardiography in predicting left atrial appendage (LAA) thrombosis in patients with non-valvular atrial fibrillation.

METHODS

The clinical data of 164 atrial fibrillation patients receiving cardiac CTA and real-time three-dimensional transoesophageal echocardiography (RT-3D-TEE) were retrospectively analysed. The patients were divided into group A (anticoagulant treatment group, n = 112) and group B (selective anticoagulant treatment group, n = 52) according to the CHA2DS2-VASc score, which scored for the presence or absence of congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, stroke/transient ischaemic attack, vascular disease, age 65-74 years and gender (female). The CHA2DS2-VASc score was used to predict risk of thromboembolism from atrial fibrillation. The correlations of CHA2DS2-VASc score with CTA-based LAA classification and RT-3D-TEE measurement parameters were explored using Spearman's analysis. Receiver operating characteristic (ROC) curves were plotted to explore the predictive value of CTA and RT-3D-TEE for LAA thrombus.

RESULTS

There were significant differences in age, disease course, hypertension, diabetes mellitus, coronary heart disease, heart failure, stroke/transient ischaemic attack/thromboembolism, vascular disease, B-type natriuretic peptide and serum uric acid levels, CHA2DS2-VASc score, LAA classification, left ventricular ejection fraction (LVEF), left atrial diameter (LAD), maximum diameter of LAA orifice, minimum diameter of LAA orifice and LAA length (p < 0.05). CHA2DS2- VASc score was positively correlated with cauliflower LAA, LAD, maximum diameter of LAA orifice, minimum diameter of LAA orifice and LAA length, and negatively correlated with LVEF (p < 0.001). ROC curve analysis indicated that CTA, RT-3D-TEE and CHA2DS2-VASc score had similar predictive values for risk of LAA thrombosis in atrial fibrillation patients, with the areas under the curve being 0.778, 0.814 and 0.792, respectively.

CONCLUSIONS

Both CTA and RT-3D-TEE had high predictive values for LAA thrombosis in atrial fibrillation patients.

Safety and efficacy of percutaneous atrial appendage closure followed by antiplatelet therapy in a high-risk population: single-center experience with a WATCHMAN device

Introduction

In our everyday practice we encounter many patients with non-valvular atrial fibrillation with either a contraindication to oral anticoagulation or with its inefficiency.

Aim

To investigate whether left atrial appendage closure (LAAC) followed by post-procedure antiplatelet therapy is safe and efficient in a high-risk population.

Material and methods

Ninety-one (48 males) consecutive patients with non-valvular atrial fibrillation (NVAF) underwent an LAAC procedure using a first-generation WATCHMAN 2.5 device followed by antiplatelet therapy. Clinical and transesophageal echocardiography data were collected at baseline and at the follow-up visit.

Results

The median (IQR) CHA2DS2-VASc score was 5 (4.0-6.0) and the HAS-BLED score was 3 (3.0-4.0); the mean (SD) age was 74.4 (8.4). A bleeding history was observed in 89% of patients and 24.2% of patients had a history of stroke or transient ischemic attack (TIA). The procedure was successful in 98.9%. Post-procedure therapy was dual antiplatelet therapy in 85 patients; 3 patients received single antiplatelet therapy and the therapy was maintained until the follow-up visit. Peri-procedural complications were tamponade (3.3%), pericardial effusion (2.2%) and two deaths (2.2%) with no bleeding or vascular complications. The median follow-up was 67 (52.75-84.75) days. Primary safety endpoint (bleeding BARC type 3 or more, tamponade, pericardial effusion, and device embolization) and primary efficacy endpoint (stroke or TIA, hemorrhagic stroke, peripheral embolism, cardiovascular (CV) and non-CV death) were observed in 2 and 4 patients, respectively.

Conclusions

The LAAC procedure followed by antiplatelet therapy seems to be safe and efficient in the high-risk population. Further studies in this field are required.

Management and Anticoagulation Treatment of Non-Valvular Atrial Fibrillation in Elderly Patients: The Dali Study

Background

Non-valvular atrial fibrillation (NVAF) is associated with increased stroke in elderly populations, yet anticoagulant therapy is underutilized. We analyzed clinical characteristics and anticoagulation treatment rates of elderly NVAF patients hospitalized in Dali, China, to identify potential contributing factors.

Methods

We collected data for 155 elderly patients with NVAF aged ≥60 years, from July 01, 2020, to December 31, 2021. We analyzed the awareness rate, clinical characteristics, and anticoagulant treatment rate of atrial fibrillation (AF), and identified factors influencing treatment. Patients were followed up one year after discharge to assess vital status, cardiovascular events, and anticoagulation therapy status.

Results

Among 155 patients, 52.26% were female, and the average age was 75.77 years. The awareness rate of AF was 47.74% at admission, and only 21.94% received anticoagulant therapy. After discharge, the rate of anticoagulant therapy significantly increased to 70.97%, and 89.09% used new oral anticoagulants. Thromboembolic history and persistent AF predicted anticoagulant therapy at discharge, while male gender, previous bleeding history, and antiplatelet therapy predicted non-anticoagulant therapy. Out of 133 patients who completed a one-year follow-up, 23.31% died, 3.01% had strokes, and 3.01% experienced bleeding. Anticoagulant therapy decreased to 51.96% during the follow-up year.

Conclusion

Our findings highlight the low awareness rate and anticoagulant treatment rate, and high mortality among elderly NVAF patients in Dali. The development of comprehensive intervention strategies is critical to standardize AF management and improve prognosis.

Trends in direct oral anticoagulant (DOAC) prescribing in English primary care (2014-2019)

BACKGROUND

In England, most prescribing of direct-acting oral anticoagulants for atrial fibrillation (AF) is in primary care. However, there remain gaps in our understanding of dosage and disparities in use. We aimed to describe trends in direct oral anticoagulant (DOAC) prescribing, including dose reduction in people with renal impairment and other criteria, and adherence.

METHODS

Using English primary care sentinel network data from 2014 to 2019, we assessed appropriate DOAC dose adjustment with creatinine clearance (CrCl). Our primary care sentinel cohort was a subset of 722 general practices, with 6.46 million currently registered patients at the time of this study.

RESULTS

Of 6 464 129 people in the cohort, 2.3% were aged ≥18 years with a diagnosis of AF, and 30.8% of these were prescribed vitamin K antagonist and 69.1% DOACs. Appropriate DOAC prescribing following CrCl measures improved between 2014 and 2019; dabigatran from 21.3% (95% CI 15.1% to 28.8%) to 48.7% (95% CI 45.0% to 52.4%); rivaroxaban from 22.1% (95% CI 16.7% to 28.4%) to 49.9% (95% CI 48.5% to 53.3%); edoxaban from 10.0% (95% CI 0.3% to 44.5%) in 2016 to 57.6% (95% CI 54.5% to 60.7%) in 2019; apixaban from 30.8% (95% CI 9.1% to 61.4%) in 2015 to 60.5% (95% CI 57.8% to 63.2%) in 2019.Adherence was highest for factor Xa inhibitors, increasing from 50.1% (95% CI 47.7% to 52.4%) in 2014 to 57.8% (95% CI 57.4% to 58.2%) in 2019. Asian and black/mixed ethnicity was associated with non-adherence (OR 1.81, 95% CI 1.56 to 2.09) as was male gender (OR 1.19, 95% CI 1.15 to 1.22), higher socioeconomic status (OR 1.60, 95% CI 1.52 to 1.68), being an ex-smoker (OR 1.12, 95% CI 1.06 to 1.19) and hypertension (OR 1.07, 95% CI 1.03 to 1.17).

CONCLUSIONS

The volume and quality of DOAC prescribing has increased yearly. Future interventions to augment quality of anticoagulant management should target disparities in adherence.

Novel Pulmonary Delivery of Drugs for the Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, affecting approximately 335 million patients worldwide. Comprehensive pharmacological treatment of AF includes medications for rate or rhythm control and anticoagulants to reduce the risk of thromboembolism; yet, these agents have significant limitations. Oral anti-arrhythmic agents have a slow onset of action, and rapid onset formulations require hospitalization for intravenous therapy. Orally administered drugs also require high doses to attain therapeutic levels, and thus dose-related severe adverse effects are often unavoidable. Given the therapeutic benefits of inhaled drug delivery, including rapid onset of action and very low doses to achieve therapeutic efficacy, this review will discuss the benefits of novel pulmonary delivery of drugs for the management of AF.

Psychiatric symptoms in patients with non-valvular atrial fibrillation

Background

Atrial fibrillation (AF) is one of the leading causes of hospitalization and even death worldwide. Complex bidirectional associations have been suggested between psychiatric disorders and AF disease. This study was conducted to investigate the prevalence of psychiatric symptoms in a cohort of Egyptian population presented with symptomatic non-valvular AF (NVAF) and to identify the high-risk subjects in need for professional psychiatric consultation. A total of 100 eligible symptomatic NVAF patients were recruited in this cross-sectional study. Each patient was subjected to: (1) cardiac evaluation included electrocardiogram, trans-esophageal echocardiography, and the European Heart Rhythm Association (EHRA). (2) Psychiatric evaluation consisted of clinical psychiatric interviewing, Hospital Anxiety and Depression Scales (HADS), Mini–Mental State Examination (MMSE), type-D personality screening, and the short form-36 (SF-36) health survey for the assessment of health-related quality of life (HRQoL).

Results

Forty-four percent of our enrolled AF patients had anxiety symptoms, 32% had depressive symptoms, 24% had mild cognitive impairment, and 32% had type-D personality. Linear regression analysis demonstrated that the left atrial dimension (LAD) and the age were the main significant predictors of MMSE, while the main predictors of HADS were SF-36 (physical functioning and general health) and the age. Neither psychiatric symptoms, nor type-D personality was a significant predictor for the evaluated cardiac parameters.

Conclusions

Mild cognitive impairment as well as depressive and anxiety symptoms is not uncommon associates with NVAF patients. Assessment of cognitive function and HRQoL is strongly advised for AF patients presented with enlarged LAD particularly among old adults.

Stroke, Thrombosis, Bleeding and Addiction to Anticoagulants in the Context of Course Therapy: A Pharmacologic Perspective

After reading with great interest the article entitled: "Non-vitamin K antagonist oral anticoagulants (NOACs) do not increase the risk of hepatic impairment in patients with non-valvular atrial fibrillation: insights from multi-source medical data" authored by Zhi-Chun Gu et al. and published by Reviews in Cardiovascular Medicine, we would like to add the following thoughts. Oral anticoagulants are generally accepted in patients with non-valvular atrial fibrillation to prevent thrombosis and stroke. Since anticoagulants are taken daily for many months in these patients, we cannot rule out chronic poisoning and the development of liver failure. But another complication is just as likely, that being bleeding. Thus, the determining risk factor for the health of patients with a prolonged course of oral anticoagulants is hypofunctional activity of the blood coagulation system, which remains at the same level throughout the course of treatment. At the same time, it is the activity of the blood coagulation system that is an important and very sensitive link of adaptation to various external and internal factors, including anticoagulants. The fact is that regular and prolonged oral use of anticoagulants is likely to develop and tolerance to them. That is why it is necessary to carefully study the relationship between the dose of oral anticoagulants, the duration of pharmacotherapy and the development of thrombosis (bleeding) in patients with non-valvular atrial fibrillation.

Direct oral anticoagulants in atrial fibrillation following cardiac surgery: a systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Direct oral anticoagulants (DOACs) have been increasingly used as anticoagulation therapy in the postoperative period. However, their effectiveness in post-cardiac surgical atrial fibrillation is yet to be determined.

METHODS

We conducted a meta-analysis, searching three international databases from 1 January 2003 to 26 January 2022 for studies reporting on DOACs in at least 10 adult patients (>18 yr of age) with post-cardiac surgical atrial fibrillation. The primary outcomes were major neurological events (MNEs) and bleeding; secondary outcomes were mortality, hospital and ICU length of stay, cost, and other complications from therapy. We included studies of any design, including RCTs, cohort studies with and without propensity score matching methods, and single-armed case series.

RESULTS

Twelve studies (8587 DOACs; 8315 warfarin) were included in this meta-analysis. The incidences of postoperative bleeding and MNEs with DOACs were 7.3% (95% confidence interval [CI]: 3.4-14.7%) and 2.2% (95% CI: 0.9-4.9%), respectively. The incidence of MNEs was lower in high-risk patients, including those with hypertension and higher CHA₂DS₂-VASc score, whereas patients with prior transient ischaemic attack or stroke had higher incidence of bleeding. Trial sequential analysis revealed that the cumulative Z-curve crossed the conventional boundary of benefit. Compared with warfarin, DOACs reduced the risk of bleeding (relative risk [RR] 0.74; 95% CI: 0.62-0.89; P=0.0011) and MNEs (RR 0.63; 95% CI: 0.48-0.83; P=0.0012) but not mortality (RR 1.02; 95% CI: 0.77-1.35; P=0.090).

CONCLUSIONS

DOACs reduced bleeding and MNEs in patients with post-cardiac surgical atrial fibrillation, appearing safer than warfarin in this context. However, which DOAC provides the most effective anticoagulation in this patient population needs further investigation.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42021282777.

Role of glomerular filtration rate-modifying drugs in the development of anticoagulant-related nephropathy

Introduction

Anticoagulant‐related nephropathy (ARN), that was described in humans first as warfarin‐related nephropathy, is characterized by acute kidney injury and red blood cell (RBC) tubular casts in the kidney. 5/6 nephrectomy (5/7NE) rats treated with warfarin or dabigatran show changes in kidney function and morphology that are similar to human disease. The role of glomerular filtration rate (GFR) in the pathogenesis of ARN is not clear. The aim of these studies was to elucidate the role of GFR in the pathogenesis of dabigatran‐induced ARN in 5/6NE rats.

Methods

5/6NE rats were treated per os with 150 mg/kg/day dabigatran alone or with drugs that lower (enalapril, 1.5 mg/kg/day) or increase (albuterol, 4.0 mg/kg/day) GFR for 7 days. Changes in coagulation and kidney function were recorded daily. Kidney morphology was evaluated on day 7 after the treatment.

Results

Dabigatran resulted in activated partial thromboplastin time increase that was not affected by GFR‐modifying drugs. Blood pressure was significantly lower in 5/6NE rats treated with enalapril and dabigatran as compared to dabigatran alone. The GFR was decreased by 35% in enalapril/dabigatran‐ and increased by 26% in albuterol/dabigatran‐treated animals. There were no changes in serum creatinine, hematuria or urinary kidney injury molecule (KIM‐1) levels when GFR‐modifying drugs were added to dabigatran. All dabigatran‐treated animals had RBC casts in the kidney regardless of the GFR modification.

Conclusions

GFR does not play a significant role in the dabigatran‐induced acute kidney injury in 5/6 nephrectomy model in rats. Based in these data, modification of GFR in patients with ARN is not warranted.