Anticoagulation in atrial fibrillation

Explainable paroxysmal atrial fibrillation diagnosis using an artificial intelligence-enabled electrocardiogram

BACKGROUND/AIMS

Atrial fibrillation (AF) significantly contributes to global morbidity and mortality. Paroxysmal atrial fibrillation (PAF) is particularly common among patients with cryptogenic strokes or transient ischemic attacks and has a silent nature. This study aims to develop reliable artificial intelligence (AI) algorithms to detect early signs of AF in patients with normal sinus rhythm (NSR) using a 12-lead electrocardiogram (ECG).

METHODS

Between 2013 and 2020, 552,372 ECG traces from 318,321 patients were collected and split into training (n = 331,422), validation (n = 110,475), and test sets (n = 110,475). Deep neural networks were then trained to predict AF onset within one month of NSR. Model performance was evaluated using the area under the receiver operating characteristic curve (AUROC). An explainable AI technique was employed to identify the inference evidence underlying the predictions of deep learning models.

RESULTS

The AUROC for early diagnosis of PAF was 0.905 ± 0.007. The findings reveal that the vicinity of the T wave, including the ST segment and S-peak, significantly influences the ability of the trained neural network to diagnose PAF. Additionally, comparing the summarized ECG in NSR with those in PAF revealed that nonspecific ST-T abnormalities and inverted T waves were associated with PAF.

CONCLUSION

Deep learning can predict AF onset from NSR while detecting key features that influence decisions. This suggests that identifying undetected AF may serve as a predictive tool for PAF screening, offering valuable insights into cardiac dysfunction and stroke risk.

Long-Term Outcomes of Tricuspid Valve Replacement With Mechanical Versus Tissue Valves: Meta-Analysis of Reconstructed Time-to-Event Data

Tricuspid valve replacement (TVR) with mechanical versus tissue valves remains a controversial subject. To evaluate the long-term effects of types of valves on patient-relevant outcomes, we performed a systematic review with meta-analysis of reconstructed time-to-event data of studies published by March 15, 2024 (according to referred the Reporting Items for Systematic Reviews and Meta-analyses guidelines). A total of 21 studies met our eligibility criteria and included 7,166 patients (mechanical: 2,495 patients, 34.8%). Patients who underwent mechanical TVR had a lower risk of death than those who received a tissue valve (hazard ratio [HR] 0.77, 95% confidence interval [CI] 0.70 to 0.84, p <0.001). Mechanical TVR was associated with lifetime gain, as evidenced by the restricted mean survival time, which was 2.2 years longer in patients who underwent TVR with mechanical valves (12.4 vs 10.2 years, p <0.001). Our landmark analysis for reoperations revealed the following: from the time point 0 to 7 years, we found no difference in the risk of reoperation between mechanical and tissues valves (HR 0.98, 95% CI 0.60 to 1.61, p = 0.946); however, from the time point 7 years onward, we found that mechanical TVR had a lower risk of reoperation in the follow-up (HR 0.24, 95% CI 0.08 to 0.72, p = 0.001). The meta-regression analysis demonstrated a modulating effect of atrial fibrillation on the association between mechanical valves and mortality; the HRs for all-cause death tended to decrease in the presence of populations with a larger proportion of atrial fibrillation (p = 0.018). In conclusion, our results suggest that TVR with mechanical valves, whenever considered clinically reasonable and accepted by patients as an option, can offer a better long-term survival and lower risk of reoperation in the long run.

Anticoagulation in Atrial Fibrillation Associated With Cardiac Amyloidosis: A Narrative Review

Cardiac amyloidosis (CA) involves the abnormal deposition and accumulation of amyloid proteins in the heart muscle. A hallmark of disease progression is declining heart function, which can lead to structural irregularities, arrhythmias, and ultimately heart failure. Atrial fibrillation (AF) is the most common arrhythmia that presents in CA patients, and this arrhythmia is significant because it can moderately increase the risk of patients developing intracardiac thrombi, thereby putting them at risk for thromboembolic events. The management of this complication entails the use of anticoagulants like vitamin K antagonists and direct oral anticoagulants to reduce the risk of thrombus formation. This article seeks to review AF in CA and the use of anticoagulation therapy for the management and reduction of thromboembolic risk. The major conclusions of this review are centered around the need for safe administration of anticoagulant therapy to CA patients, regardless of their CHA2DS2-VASc risk score. This review highlights the importance of taking a multidisciplinary or collaborative approach to CA treatment to ensure that all aspects of this multifaceted disease can be properly managed while minimizing adverse events like bleeding risk and drug-drug interactions.

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.

Physicians' Perspective on Percutaneous Left Atrial Appendage Closure in Patients with Atrial Fibrillation and Chronic Kidney Disease in Pakistan

This study, conducted in Pakistan, examines the perspectives of 1200 physicians across diverse specialties regarding Left Atrial Appendage Occlusion (LAAO) procedures for atrial fibrillation (AF) patients with chronic kidney disease (CKD). Using a random sampling approach, physicians participated in a survey that assessed their familiarity with LAAO, views on its effectiveness and safety, experience levels, and encountered challenges. The results unveil a spectrum of knowledge levels among physicians, reinforcing the need for tailored medical education and training programs. The majority of respondents were between 30 and 49 years old (59.8 %). A notable proportion, 33.3 %, had limited or no knowledge of LAAO, with 16.7 % having never heard of the procedure, and 16.7 % having limited knowledge but no experience. About 36.2 % of physicians believed LAAO was moderately to extremely effective in reducing stroke risk, with 23.3 % considering it very effective and 25.4 % believing it to be extremely effective. The most commonly cited clinical indications were a history of recurrent strokes despite anticoagulation (34.6 %) and a high CHA2DS2-VASc score (27.3 %). Renal considerations played a significant role, with 33.1 % considering LAAO for CKD stage 4 or 5 patients with elevated stroke risk. Patient preferences, such as a desire to avoid long-term anticoagulant use, were important for 28.7 % of physicians. Identified challenges encompass limited equipment access, training gaps, patient reluctance, and administrative complexities. Furthermore, the study underscores the pivotal role of shared decision-making in healthcare delivery. These findings lay essential groundwork for improving LAAO utilization and patient-centered care in Pakistan's healthcare system.

Chronic Anticoagulation in Patients with Atrial Fibrillation and COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with hypercoagulability. It remains uncertain whether ongoing anticoagulation for atrial fibrillation (AF) in patients who later contract COVID-19 improves clinical outcomes.

OBJECTIVES

To compare chronic oral anticoagulation with no previous anticoagulation in patients with AF who contracted a COVID-19 infection concerning the outcomes of all-cause mortality, COVID-19 mortality, intensive care unit (ICU) admission, and hospitalization.

METHODS

We systematically searched PubMed, Embase, and Cochrane Library for eligible studies from inception to December 2022. We included studies comparing COVID-19 outcomes in patients with versus without prior chronic anticoagulation for AF. Risk ratios (RR) with 95% confidence intervals (CI) were pooled with a random-effects model. The level of significance was set at p < 0.05. Quality assessment and risk of bias were performed according to Cochrane recommendations.

RESULTS

Ten studies comprising 1,177,858 patients with COVID-19 and AF were identified, of whom 893,772 (75.9%) were on prior chronic anticoagulation for AF. In patients with COVID-19, being on chronic anticoagulation for AF significantly reduced all-cause mortality (RR 0.75; 95% CI 0.57 to 0.99; p = 0.048; I2 = 89%) and COVID-19-related mortality (RR 0.76; 95% CI 0.72 to 0.79; p < 0.001; I2 = 0%) when compared with no prior anticoagulation. In contrast, there was no difference between groups regarding hospitalization (RR 1.08; 95% CI 0.82 to 1.41; p = 0.587; I2 = 95%) or ICU admission (RR 0.86; 95% CI 0.68 to 1.09; p = 0.216; I2 = 69%).

CONCLUSIONS

In this meta-analysis, chronic anticoagulation for patients with AF who contracted COVID-19 was associated with significantly lower rates of all-cause mortality and COVID-19-related mortality as compared with no previous anticoagulation.

Does prescribing apixaban or rivaroxaban versus warfarin for patients diagnosed with atrial fibrillation save health system costs? A multivalued treatment effects analysis

BACKGROUND

Non-valvular atrial fibrillation (AF) is a common heart arrhythmia in the elderly population. AF patients are at high-risk of ischemic strokes, but oral anticoagulant (OAC) therapy reduces such risks. Warfarin had been the standard OAC for AF patients, however its effectiveness is highly variable and dependent on close monitoring of the anticoagulant response. Newer OACs such as rivaroxaban and apixaban address these drawbacks but are more costly. It is uncertain which OAC therapy for AF is cost-saving from the healthcare system perspective.

METHODS

We followed a cohort of patients in Ontario, Canada, aged ≥ 66 who were newly diagnosed with AF and prescribed OACs between 2012 and 2017. We used a two-stage estimation procedure. First, we account for the patient selection into OACs using a multinomial logit regression model and estimated propensity scores. Second, we used an inverse probability weighted regression adjustment approach to determine cost-saving OAC options. We also examined component-specific costs (i.e., drug, hospitalization, emergency department and physician) to understand the drivers of cost-saving OACs.

RESULTS

We found that compared to warfarin, rivaroxaban and apixaban treatments were cost-saving options, with per-patient 1-year healthcare cost savings at $2436 and $1764, respectively. These savings were driven by cost-savings in hospitalization, emergency department visits, and physician visits, outweighing higher drug costs. These results were robust to alternative model specifications and estimation procedures.

CONCLUSIONS

Treating AF patients with rivaroxaban and apixaban than warfarin reduces healthcare costs. OAC reimbursement policies for AF patients should consider rivaroxaban or apixaban over warfarin as the first-line treatment.

Patterns of Anticoagulation Use and All-Cause of Mortality in Cancer Patients with Atrial Fibrillation

BACKGROUND

There is uncertainty regarding the clinical benefit of anticoagulant (AC) treatment in patients with cancer with atrial fibrillation (AF). We aimed to evaluate the distribution and patterns of AC use and its impact on all-cause mortality in cancer patients with AF.

METHODS

A total of 1,653 patients with cancer diagnosed with AF were included in this retrospective cohort analysis. Multivariable logistic regression was applied to identify the clinical predictors of anticoagulant prescription. Kaplan-Meier curve with a log-rank test was used to compare the probability of survival between the AC and non-AC groups. Multivariate Cox proportional hazard regression models were implemented to evaluate the influences of various variables on all-cause death.

RESULTS

Of 1,653 patients with cancer with AF, 971 (58.7%) did not receive a prescription for AC. Among patients with CHA2DS2-VASC ≥2 in men or ≥3 in women and HAS-BLED <3, 56.5% were not prescribed AC. Rivaroxaban and warfarin are more frequently used than dabigatran, mainly in patients with lung and breast cancer. Over a median follow-up of 36 months, 776 deaths were identified. The Kaplan-Meier curve suggested that patients with AC prescriptions had better clinical outcomes. On multivariate Cox proportional risk regression analysis, AC prescription was significantly associated with a lower risk of all-cause mortality (hazard ratio, 0.78; 95% confidence interval, 0.66-0.91; P = 0.002).

CONCLUSIONS

The prescription of anticoagulants in patients with cancer with AF was suboptimal. AC prescription at discharge was associated with a decreased risk of all-cause mortality.

IMPACT

This study highlights the importance of AC prescriptions in patients with cancer with AF.

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.

An Overview of Systematic Reviews on the Effectiveness of Wenxin Keli in the Treatment of Atrial Fibrillation

Background

Atrial fibrillation is one of the most common cardiac arrhythmias. Wenxin Keli (WXKL) is a Chinese herbal extract widely used in China to treat patients with atrial fibrillation. This study aimed to outline and summarize the current evidence of systematic reviews (SRs)/meta-analyses (MAs) investigating the clinical efficacy of WXKL in atrial fibrillation.

Methods

From inception to December 2021, 6 electronic databases in English and Chinese were searched for potential SRs/MAs. The GRADE (Grading of Recommendations Assessment, Development, and Evaluation), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) checklist, and AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews-2) were used to evaluate the quality of the evidence, reporting, and methodology of SRs/MAs regarding WXKL for the treatment of atrial fibrillation.

Results

A total of 8 SRs/MAs were included in the present study. The results of AMSTAR-2 and PRISMA were unsatisfactory for the main insufficiency founded in registration and protocol, search strategy, excluded study statement, evidence certainty assessment, and funding and conflict of interest information. All the included SRs/MAs were assessed as very low in methodological quality. Moreover, 23 outcomes were evaluated by GRADE for the certainty of evidence, and 2 outcomes were assessed as moderate, while 15 were low and 6 were very low. Risk of bias and publication bias contributed to the downgrading.

Conclusion

WXKL may be clinically efficacious and safe for the treatment of atrial fibrillation. This finding, however, should be regarded with caution because of the low level of evidence and methodological qualities of the involved SRs/MAs. More standardized, rigorous, and comprehensive SRs/MAs and randomized control trials are needed to provide strong evidence to reach more convincing conclusions.

Real-World Management and Clinical Outcomes of Stroke Survivors With Atrial Fibrillation: A Population-Based Cohort in Spain

Objective: Despite the continuous update of clinical guidelines, little is known about the real-world management of patients with atrial fibrillation (AF) who survived a stroke. We aimed to assess patterns of therapeutic management of stroke survivors with AF and clinical outcomes using data from routine practice in a large population-based cohort. Methods: A population-based retrospective cohort study of all patients with AF who survived a stroke, from January 2010 to December 2017 in the Valencia region, Spain (n = 10,986), was carried out. Treatment strategies and mean time to treatment initiation are described. Temporal trends are shown by the management pattern during the study period. Factors associated with each pattern (including no treatment) vs. oral anticoagulant (OAC) treatment were identified using logistic multivariate regression models. Incidence rates of clinical outcomes (mortality, stroke/TIA, GI bleeding, and ACS) were also estimated by the management pattern. Results: Among stroke survivors with AF, 6% were non-treated, 23% were prescribed antiplatelets (APT), 54% were prescribed OAC, and 17% received OAC + APT at discharge. Time to treatment was 8.0 days (CI 7.6-8.4) for APT, 9.86 (CI 9.52-10.19) for OAC, and 16.47 (CI 15.86-17.09) for OAC + APT. Regarding temporal trends, management with OAC increased by 20%, with a decrease of 50% for APT during the study period. No treatment and OAC + APT remained relatively stable. The strongest predictor of no treatment and APT treatment was having the same management strategy pre-stroke. Those treated with APT had the highest rates of GI bleeding and recurrent stroke/TIA, and untreated patients showed the highest rates of mortality. Conclusion: In this large population-based cohort using real-world data, nearly 30% of AF patients who suffered a stroke were untreated or treated with APT, which overall is not recommended. Treatment was started within 2 weeks as recommended, except for OAC + APT, which was started later. The strong association of APT treatment or non-treatment with the same treatment strategy before stroke occurrence suggests a strong therapeutic inertia and opposes recommendations. Patients under these two strategies had the highest rates of adverse outcomes. An inadequate prescription poses a great risk on patients with AF and stroke; thus monitoring their management is necessary and should be setting-specific.

Association of Vitamin K and Non-Vitamin K Oral Anticoagulant Use and Cancer Incidence in Atrial Fibrillation Patients

The association between the use of vitamin K antagonists (VKAs) and cancer risk reduction remains unclear. We aimed to assess the association between the use of VKAs or direct oral anticoagulants (DOACs) and the incidence of cancer in a large cohort of patients with atrial fibrillation (AF) by means of a population‐based, propensity‐weighted cohort study using population‐wide databases including patients diagnosed with nonvalvular AF (NVAF) followed for up of 5 years (median 2.94 years). We created two cohorts based on the initiation therapy (VKA or DOAC). Initiation with VKA or DOAC was defined as filling a prescription with no previous exposure in the preceding 12 months. Cancer diagnoses of any type and for specific tumors (lung, colon, prostate, bladder, and breast). We included 39,989 patients, 31,200 (78.0%) in the VKA cohort. Incidence rate for any cancer was 12.45 per 1,000 person‐year in the DOAC cohort vs. 14.55 in the VKA cohort (adjusted hazard ratio (HR): 1.16, 95% confidence interval (CI): 1.02–1.32). In secondary outcomes, no differences were found for specific types of cancer, such as lung (HR: 1.28, CI: 0.89–1.83), colon (HR: 0.84, CI: 0.62–1.13), prostate (HR: 1.40, CI: 0.94–2.10), bladder (HR: 1.07, CI: 0.76–1.52), and breast (HR: 1.05, CI: 0.66–1.69). Sensitivity analyses yielded similar results. Subgroup analyses also produced consistent findings, except for men, for whom VKA was associated with a lower risk of colon cancer (HR: 0.68, 95% CI: 0.48–0.96). Our results do not confirm a chemoprotective effect of VKA when compared with DOAC in a large, real‐world cohort of patients with NVAF followed for up to 5 years.

Efficacy of a joint didactic intervention using the Junta De Andalucía School for Patients method to control prothrombin time in patients taking anticoagulants: protocol for a randomized controlled trial

BACKGROUND

Oral anticoagulant drugs represent an essential tool in the prevention of thromboembolic events. The ones in widespread use are vitamin K antagonists, whose plasma level is monitored by measuring prothrombin time using the international normalized ratio. If its values are out of the recommended range, the patient will have a higher risk of suffering from thromboembolic or hemorrhagic complications. Previous research has shown that approximately 33% of patients keep having values at an inappropriate level. The purpose of the proposed study is to improve the international normalized ratio control results by a joint didactic intervention based on the Junta de Andalucía School for Patients method that will be implemented by anticoagulated patients themselves.

METHODS

A randomized controlled trial will be undertaken at primary care centers from one healthcare area in Málaga (Andalusia, Spain).

STUDY POPULATION

patients participating in an oral anticoagulant therapy program of vitamin K antagonists. First step: identification of patients in the oral anticoagulation therapy program with international normalized ratio control of the therapeutic level at 65% or less over total time. Second step: patients with international normalized ratio (INR) control figures under 2 or above 3 will be assigned to two different groups: Group 1 or joint intervention group: patients will be instructed in the joint didactic "from peer to peer," by a previously trained and expert anticoagulant patient. Group 2 or control group: the control group will receive the usual clinical practice. They will be evaluated by nurses about once a month, except for cases in which their INR figures are under 2 or above 3, and those patients will be evaluated more frequently. A total of 312 individuals will be required (156 in each group) to detect differences in INR figures equal to or higher than 15% between the groups.

STUDY VARIABLES

time on therapeutic levels before and after the intervention; sociodemographic variables; vital signs; the existence of cardiovascular risk factors or accompanying diseases in the clinical records; laboratory test including complete blood counts, bleeding time, and prothrombin time or partial thromboplastin time; and blood chemistry, other prescribed drugs, and social support. A quasi-experimental analytic study with before-after statistical analysis of the intervention will be conducted. Linear regression models will be applied for the main variable results (international normalized ratio value, time on therapeutic level) inputting sociodemographic variables, accompanying diseases, and social support.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03647254 . Registered on 27 August 2018.

Patterns of Anticoagulation Use in Patients With Cancer With Atrial Fibrillation and/or Atrial Flutter

Background

Atrial fibrillation (AF) is a common cardiovascular complication affecting patients with cancer, but management strategies are not well established.

Objectives

The purpose of this retrospective cohort study was to evaluate cross-sectional patterns of anticoagulation (AC) use in patients with cancer with AF or atrial flutter (AFL) on the basis of their risk for stroke and bleeding.

Methods

Patients with cancer and electrocardiograms showing AF or AFL performed at Moffitt Cancer Center in either the inpatient or outpatient setting were included in this retrospective analysis. We described percentages of AC prescription by stroke and bleeding risk, as determined by individual CHA₂DS₂-VASc and HAS-BLED scores, respectively. Multivariable logistic regression evaluated clinical variables independently associated with anticoagulant prescription.

Results

The prevalence of electrocardiography-documented AF or AFL was 4.8% (n = 472). The mean CHA₂DS₂-VASc score was 2.8 ± 1.4. Among patients with CHA₂DS₂-VASc scores ≥2 and HAS-BLED scores <3, 44.3% did not receive AC, and of these, only 18.3% had platelet values <50,000/μl. In multivariable analysis, older age, hypertension, prior stroke, and history of venous thromboembolism were each directly associated with AC use, while current chemotherapy use, prior bleeding, renal disease, and thrombocytopenia were each inversely associated with AC use.

Conclusions

Nearly one-half of patients with cancer, the majority with normal platelet counts, had an elevated risk for stroke but did not receive AC. In addition to known predictors, current chemotherapy use was independently associated with a lower odds of AC use. This study highlights the need to improve the application of AF treatment algorithms to cancer populations.

Trends in prevalence of acute stroke impairments: A population-based cohort study using the South London Stroke Register

BACKGROUND

Acute stroke impairments often result in poor long-term outcome for stroke survivors. The aim of this study was to estimate the trends over time in the prevalence of these acute stroke impairments.

METHODS AND FINDINGS

All first-ever stroke patients recorded in the South London Stroke Register (SLSR) between 2001 and 2018 were included in this cohort study. Multivariable Poisson regression models with robust error variance were used to estimate the adjusted prevalence of 8 acute impairments, across six 3-year time cohorts. Prevalence ratios comparing impairments over time were also calculated, stratified by age, sex, ethnicity, and aetiological classification (Trial of Org 10172 in Acute Stroke Treatment [TOAST]). A total of 4,683 patients had a stroke between 2001 and 2018. Mean age was 68.9 years, 48% were female, and 64% were White. After adjustment for demographic factors, pre-stroke risk factors, and stroke subtype, the prevalence of 3 out of the 8 acute impairments declined during the 18-year period, including limb motor deficit (from 77% [95% CI 74%-81%] to 62% [56%-68%], p < 0.001), dysphagia (37% [33%-41%] to 15% [12%-20%], p < 0.001), and urinary incontinence (43% [39%-47%) to 29% [24%-35%], p < 0.001). Declines in limb impairment over time were 2 times greater in men than women (prevalence ratio 0.73 [95% CI 0.64-0.84] and 0.87 [95% CI 0.77-0.98], respectively). Declines also tended to be greater in younger patients. Stratified by TOAST classification, the prevalence of all impairments was high for large artery atherosclerosis (LAA), cardioembolism (CE), and stroke of undetermined aetiology. Conversely, small vessel occlusions (SVOs) had low levels of all impairments except for limb motor impairment and dysarthria. While we have assessed 8 key acute stroke impairments, this study is limited by a focus on physical impairments, although cognitive impairments are equally important to understand. In addition, this is an inner-city cohort, which has unique characteristics compared to other populations.

CONCLUSIONS

In this study, we found that stroke patients in the SLSR had a complexity of acute impairments, of which limb motor deficit, dysphagia, and incontinence have declined between 2001 and 2018. These reductions have not been uniform across all patient groups, with women and the older population, in particular, seeing fewer reductions.

A study of knowledge, attitudes, and practices of primary care physicians toward anticoagulant therapy in patients with non-valvular atrial fibrillation in Shanghai, China

Background

As a large number of Community Health Service (CHS) centers in China face the majority of patients with non-valvular atrial fibrillation (NVAF), primary care physicians (PCPs) play a primary role in the prevention of embolization. Therefore, an awareness of anticoagulant management in patients with NVAF must be brought into focus among PCPs in China. This study investigated PCPs’ knowledge, attitudes, and practices toward anticoagulant therapy in patients with NVAF, to help them understand their shortcomings regarding oral anticoagulant (OAC) therapy in preventing embolization.

Method

This was a cross-sectional observational study of 462 PCPs in CHS centers across Shanghai. We used a self-administered questionnaire to collect data from September to December 2017. A stratified random cluster sampling was adopted in the 90 CHS centers with the family medicine residency program.

Result

Among 462 participants, 69.3% (320/462) of females received a medical bachelor’s degree and over 50% of participants had more than 10 years of work experience. Each section for knowledge, attitude, and practice were categorized as poor (≤39.0%), fair (40.0–69.0%), and good (≥70.0%). The level of knowledge of OAC therapy for patients with NVAF among PCPs was insufficient in over half (75.8%) of the participants. The majority (89.8%) of PCPs had a positive attitude and 68.0% had modest performance in the anticoagulant management of patients with NVAF.

Conclusions

The knowledge and behaviors of PCPs were insufficient for OAC therapy to prevent embolization in patients with NVAF. The study also revealed that there is good potential for PCPs’ educational interventions to positively impact the care of patients with NVAF.

The additional value of an algorithm for atrial fibrillation at the stroke unit

BACKGROUND AND PURPOSE

The rate of newly detected (paroxysmal) atrial fibrillation (AF) during inpatient cardiac telemetry is low. The objective of this study was to evaluate the additional diagnostic yield of an automated detection algorithm for AF on telemetric monitoring compared with routine detection by a stroke unit team in patients with recent ischemic stroke or TIA.

METHODS

Patients admitted to the stroke unit of Medisch Spectrum Twente with acute ischemic stroke or TIA and no history of AF were prospectively included. All patients had telemetry monitoring, routinely assessed by the stroke unit team. The ST segment and arrhythmia monitoring (ST/AR) algorithm was active, with deactivated AF alarms. After 24 h the detections were analyzed and compared with routine evaluation.

RESULTS

Five hundred and seven patients were included (52.5% male, mean age 70.2 ± 12.9 years). Median monitor duration was 24 (interquartile range 22-27) h. In 6 patients (1.2%) routine analysis by the stroke unit team concluded AF. In 24 patients (4.7%), the ST/AR Algorithm suggested AF. Interrater reliability was low (κ, 0.388, p < 0.001). Suggested AF by the algorithm turned out to be false positive in 11 patients. In 13 patients (2.6%) AF was correctly diagnosed by the algorithm. None of the cases detected by routine analysis were missed by the algorithm.

CONCLUSIONS

Automated AF detection during 24-h telemetry in ischemic stroke patients is of additional value to detect paroxysmal AF compared with routine analysis by the stroke unit team alone. Automated detections need to be carefully evaluated.

Secondary stroke prophylaxis in atrial fibrillation patients with chronic kidney disease: a nationwide cohort study

AIMS

Oral anticoagulation (OAC) therapy as secondary stroke prophylaxis in atrial fibrillation (AF) patients with chronic kidney disease (CKD) remains unexplored and poses a clinical treatment dilemma. We assessed the long-term risk of thromboembolic events according to post-stroke OAC therapy in AF patients with CKD after their first ischaemic stroke.

METHODS AND RESULTS

We identified Danish AF patients with CKD who presented with first-time ischaemic stroke from 2005 to 2014. Chronic kidney disease was defined as a diagnosis code for CKD before baseline, defined as 100 days after stroke discharge. Post-stroke antithrombotic therapy (OAC therapy and antiplatelet therapy) was identified from prescription claims from discharge to baseline. Cumulative incidences and adjusted hazard ratios (HRs) of thromboembolic events according to post-stroke OAC therapy were examined. Of 1252 AF patients with CKD presenting with ischaemic stroke, 631 (50.4%) patients were on OAC therapy and 621 (49.6%) were on antiplatelet therapy alone at baseline [median age 76 (interquartile range, IQR 71-83) and 80 (IQR 72-86), respectively]. The median follow-up period was 1.9 years (IQR 0.8-3.6). Cumulative incidence rates of thromboembolic events and bleeding showed no significant difference between those on OAC therapy and antiplatelet therapy. The results from the multivariable analysis revealed similar results: thromboembolic risk was not modified by OAC treatment [adjusted HR 0.89, 95% confidence interval (CI) 0.73-1.09] nor was the risk of bleeding (adjusted HR 0.88, 95% CI 0.67-1.17).

CONCLUSION

Oral anticoagulation in patients with CKD and prior stroke was not associated with a reduced risk of recurrent thromboembolic events compared with antiplatelet therapy.

A consultant-led anticoagulation review of all patients in one clinical commissioning group to prevent atrial fibrillation related stroke

OBJECTIVE

Ensuring patients with Atrial fibrillation (AF) are appropriately anticoagulated across NHS Bedfordshire Clinical Commissioning Group (BCCG) with the primary goal of reducing AF-related strokes.

METHODS

With Inspira Health, BCCG adopted the Primary Care Atrial Fibrillation (PCAF) Service which is led by Consultant Cardiologists. PCAF uses retrospective clinical audit to identify patients who require prospective face-to-face review on the need for anticoagulation.

RESULTS

34 GP practices participated covering a 376 311 population (80% of BCCG). 12 573 patients' medical records were audited. The initial AF register was 7301 patients (AF prevalence 1.9%) and an additional 265 patients were identified through AF casefinder resulting in an AF prevalence of 2.0%. From 7566 patients with AF, 5831 were already on anticoagulants (77.1%), with 50.5% (n = 2947) on VKA medications and 49.5% (n = 2884) on direct oral anticoagulants (DOACs). Of the DOAC patients, 595 (20.6%) required dosage review or up to date blood tests. Case notes were reviewed for 1735 patients not on anticoagulation, with 901 (51.9%) patients deemed not eligible for anticoagulation. This left 834 (48.1%) patients who were eligible for, but not on, anticoagulation. A further 407 (13.8%) patients currently taking VKA medications were deemed sup-optimal with regards to INR control with TTR < 65%. In total 1241 patients were invited for review by a Consultant Cardiologist at their local GP practice, with an attendance rate of 90%. From all face to face and virtual consultations, 908 patients had anticoagulants prescribed, changed, management of INRs improved or were in the process of being anticoagulated at the time of follow-up. From this we would expect 36.3 AF related strokes prevented and a cost saving to the NHS of £470 200 per year.

CONCLUSION

Through comprehensive audit, BCCG have been able to ensure that patients with AF are appropriately anticoagulated in 80% of their catchment population. This has improved anticoagulation to prevent AF-related stroke.

Oral anticoagulation therapy use in patients with atrial fibrillation after the introduction of non-vitamin K antagonist oral anticoagulants: findings from the French healthcare databases, 2011-2016

OBJECTIVES

To describe (i) the trend in oral anticoagulant (OAC) use following the introduction of non-vitamin K antagonist oral anticoagulant (NOAC) therapy for stroke prevention in atrial fibrillation (AF) patients and (ii) the current patterns of use of NOAC therapy in new users with AF in France.

DESIGN

(i) Repeated cross-sectional study and (ii) population-based cohort study.

SETTING

French national healthcare databases (50 million beneficiaries).

PARTICIPANTS

(i) Patients with identified AF in 2011, 2013 and 2016 and (ii) patients with AF initiating OAC therapy in 2015-2016. PRIMARY AND SECONDARY OUTCOME MEASURES: (i) Trend in OAC therapy use in patients with AF and (ii) patterns of use of NOAC therapy in new users with AF.

RESULTS

Between 2011 and 2016, use of OAC therapy moderately increased (+16%), while use of antiplatelet therapy decreased (-22%) among all patients with identified AF. In 2016, among the 1.1 million AF patients, 66% used OAC therapy and were more likely to be treated by vitamin K antagonist (VKA) than NOAC therapy, including patients at higher risk of stroke (63.5%), while 33% used antiplatelet therapy. Among 192 851 new users of OAC therapy in 2015-2016 with identified AF, NOAC therapy (66.3%) was initiated more frequently than VKA therapy, including in patients at higher risk of stroke (57.8%). Reduced doses were prescribed in 40% of NOAC new users. Several situations of inappropriate use at NOAC initiation were identified, including concomitant use of drugs increasing the risk of bleeding (one in three new users) and potential NOAC underdosing.

CONCLUSIONS

OAC therapy use in patients with AF remains suboptimal 4 years after the introduction of NOACs for stroke prevention in France and improvement in appropriate prescribing regarding NOAC initiation is needed. However, NOAC therapy is now the preferred drug class for initiation of OAC therapy in patients with AF, including in patients at higher risk of stroke.

Quality of INR control and switching to non-Vitamin K oral anticoagulants between women and men with atrial fibrillation treated with Vitamin K Antagonists in Spain. A population-based, real-world study

BACKGROUND

Worldwide, there is growing evidence that quality of international normalized ratio (INR) control in atrial fibrillation patients treated with Vitamin K Antagonists (VKA) is suboptimal. However, sex disparities in population-based real-world settings have been scarcely studied, as well as patterns of switching to second-line Non-VKA oral anticoagulants (NOAC). We aimed to assess the quality of INR control in atrial fibrillation patients treated with VKA in the region of Valencia, Spain, for the whole population and differencing by sex, and to identify factors associated with poor control. We also quantified switching to Non-VKA oral anticoagulants (NOAC) and we identified factors associated to switching.

METHODS

This is a cross-sectional, population-based study. Information was obtained through linking different regional electronic databases. Outcome measures were Time in Therapeutic Range (TTR) and percentage of INR determinations in range (PINRR) in 2015, and percentage of switching to NOAC in 2016, for the whole population and stratified by sex.

RESULTS

We included 22,629 patients, 50.4% were women. Mean TTR was 62.3% for women and 63.7% for men, and PINNR was 58.3% for women and 60.1% for men (p<0.001). Considering the TTR<65% threshold, 53% of women and 49.3% of men had poor anticoagulation control (p<0.001). Women, long-term users antiplatelet users, and patients with comorbidities, visits to Emergency Department and use of alcohol were more likely to present poor INR control. 5.4% of poorly controlled patients during 2015 switched to a NOAC throughout 2016, with no sex differences.

CONCLUSION

The quality of INR control of all AF patients treated with VKA in 2015 in our Southern European region was suboptimal, and women were at a higher risk of poor INR control. This reflects sex disparities in care, and programs for improving the quality of oral anticoagulation should incorporate the gender perspective. Clinical inertia may be lying behind the observed low rates of switching in patient with poor INR control.

Risk factors for medication non-adherence among atrial fibrillation patients

Background

Atrial fibrillation (AF) patients are routinely prescribed medications to prevent and treat complications, including those from common co-occurring comorbidities. However, adherence to such medications may be suboptimal. Therefore, we sought to identify risk factors for general medication non-adherence in a population of patients with atrial fibrillation.

Methods

Data were collected from a large, ethnically-diverse cohort of Kaiser Permanente Northern and Southern California adult members with incident diagnosed AF between January 1, 2006 and June 30, 2009. Self-reported questionnaires were completed between May 1, 2010 and September 30, 2010, assessing patient socio-demographics, health behaviors, health status, medical history and medication adherence. Medication adherence was assessed using a previously validated 3-item questionnaire. Medication non-adherence was defined as either taking medication(s) as the doctor prescribed 75% of the time or less, or forgetting or choosing to skip one or more medication(s) once per week or more. Electronic health records were used to obtain additional data on medical history. Multivariable logistic regression analyses examined the associations between patient characteristics and self-reported general medication adherence among patients with complete questionnaire data.

Results

Among 12,159 patients with complete questionnaire data, 6.3% (n = 771) reported medication non-adherence. Minority race/ethnicity versus non-Hispanic white, not married/with partner versus married/with partner, physical inactivity versus physically active, alcohol use versus no alcohol use, any days of self-reported poor physical health, mental health and/or sleep quality in the past 30 days versus 0 days, memory decline versus no memory decline, inadequate versus adequate health literacy, low-dose aspirin use versus no low-dose aspirin use, and diabetes mellitus were associated with higher adjusted odds of non-adherence, whereas, ages 65–84 years versus < 65 years of age, a Charlson Comorbidity Index score ≥ 3 versus 0, and hypertension were associated with lower adjusted odds of non-adherence.

Conclusions

Several potentially preventable and/or modifiable risk factors related to medication non-adherence and a few non-modifiable risk factors were identified. These risk factors should be considered when assessing medication adherence among patients diagnosed with AF.

Real-world adherence to oral anticoagulants in atrial fibrillation patients: a study protocol for a systematic review and meta-analysis

INTRODUCTION

Atrial fibrillation (AF) is one of the leading causes of cerebrovascular mortality and morbidity. Oral anticoagulants (OACs) have been shown to reduce the incidence of cardioembolic stroke in patients with AF, adherence to treatment being an essential element for their effectiveness. Since the release of the first non-vitamin K antagonist oral anticoagulant, several observational studies have been carried out to estimate OAC adherence in the real world using pharmacy claim databases or AF registers. This systematic review aims to describe secondary adherence to OACs, to compare adherence between OACs and to analyse potential biases in OAC secondary adherence studies using databases.

METHODS AND ANALYSIS

We searched on PubMed, SCOPUS and Web of Science databases (completed in 26 September 2018) to identify longitudinal observational studies reporting days' supply adherence measures with OAC in patients with AF from refill databases or AF registers. The main study endpoint will be the percentage of patients exceeding the 80% threshold in proportion of days covered or the medication possession ratio. Two reviewers will independently screen potential studies and will extract data in a structured format. A random-effects meta-analysis will be carried out to pool study estimates. The risk of bias will be assessed using the Newcastle-Ottawa Scale for observational studies and we will also assess some study characteristics that could affect days' supply adherence estimates.

ETHICS AND DISSEMINATION

This systematic review using published aggregated data does not require ethics approval according to Spanish law and international regulations. The final results will be published in a peer-review journal and different social stakeholders, non-academic audiences and patients will be incorporated into the diffusion activities.

PROSPERO REGISTRATION NUMBER

CRD42018095646.

Non-bleeding Adverse Events with the Use of Direct Oral Anticoagulants: A Sequence Symmetry Analysis

Introduction

Postmarketing pharmacovigilance reports have raised concerns about non-bleeding adverse events associated with direct oral anticoagulants (DOACs), but only limited results are available from large claims databases.

Objective

The aim of this study was to assess the potential association between DOAC initiation and the onset of four types of non-bleeding adverse events by sequence symmetry analysis (SSA).

Methods

SSA was performed using nationwide data from the French National Healthcare databases (Régime Général, 50 million beneficiaries) to assess a cohort of 386,081 DOAC new users for the first occurrence of four types of non-bleeding outcomes: renal, hepatic, skin outcomes identified by using hospitalization discharge diagnoses, and gastrointestinal outcomes by using medication reimbursement. Asymmetry in the distribution of each investigated outcome occurring before and after initiation of DOAC therapy was used to test the association between DOAC therapy and these outcomes. SSA inherently controls for time-constant confounders, and adjusted sequence ratios were computed after correcting for temporal trends. Negative (glaucoma) and positive (bleeding, depressive disorders) control outcomes were used and analyses were replicated on a cohort of 310,195 patients initiating a vitamin K antagonist (VKA).

Results

This study demonstrated the expected positive association between either DOAC or VKA therapy and hospitalised bleeding and initiation of antidepressant therapy, while no association was observed between either DOAC or VKA therapy and initiation of antiglaucoma medications. For DOAC therapy, signals were the associations with hepatic outcomes, including acute liver injury [for the 3-month time window, aSR₃ = 2.71, 95% confidence interval (CI) 1.79–4.52]; gastrointestinal outcomes, including initiation of drugs for constipation and antiemetic drugs (aSR₃ = 1.31, 95% CI 1.27–1.36; and 1.17, 95% CI 1.12–1.22, respectively); and kidney diseases (aSR₃ = 1.33, 95% CI 1.29–1.37).

Conclusion

Results of this nationwide study suggest that DOACs are associated with rare but severe liver injury and more frequent gastrointestinal disorders. A low risk of kidney injury with DOAC therapy can also not be excluded.

Electronic supplementary material

The online version of this article (10.1007/s40264-018-0668-9) contains supplementary material, which is available to authorized users.

Xafran, a drug utilization study of rivaroxaban in stroke prevention in atrial fibrillation in France using a claim database

BACKGROUND

Little is known about the utilization of rivaroxaban in real life treatment settings in France.

AIMS

Objectives of this study were to describe the conditions of use and treatment persistence in patients with atrial fibrillation and treated with rivaroxaban for stroke prevention (SP-AF).

METHODS

A cohort study was performed using a representative sample of the French nationwide database. All adults who initiated rivaroxaban for SP-AF between 01/08/2012 and 31/12/2014 were included and followed for one year. Inappropriate use of rivaroxaban's was defined as use inconsistent with the summary of product characteristics.

RESULTS

In this study, 1278 patients were included, 687 (53.8%) were men and the mean age was 73.4years; 123 patients (9.6%) had a stroke and 78 (6.1%) a major bleeding event in the three years before rivaroxaban initiation. At treatment initiation 236 (18.5%) had chronic congestive heart failure, 991 (77.5%) hypertension, 247 (19.3%) diabetes and 9 (0.7%) HIV, hepatitis B or C infection. No anticoagulant had been administered in the six previous months for 777 patients (60.8%); 160 patients (12.5%) had an inappropriate use of rivaroxaban in SP-AF. At 6 and 12 months after the first delivery with rivaroxaban, 62.8%, and 51.7% (68.5% and 60.5% in sensitivity analyses) of the patients were still treated with rivaroxaban. The proportion of patients with a continuous medication availability above 80% was 96.1%.

CONCLUSION

The characteristics of patients in this study are similar to patients treated with this drug in other observational studies. Adherence and persistence with rivaroxaban can be considered good.

Valvular Heart Disease

This article outlines the diagnosis and management of commonly occurring valvular heart diseases for the primary care provider. Basic understanding of pathologic murmurs is important for appropriate referral. Echocardiography is the gold standard for diagnosis and severity grading. Patients with progressive valvular heart disease should be followed annually by cardiology and imaging should be performed based on the severity of valvular dysfunction. Surgery or intervention is recommended only when symptoms dictate or when changes in left ventricular function occur. Surgery or intervention should be performed after discussion by a heart team, including cardiologists and cardiac surgeons.

Combining value of information analysis and ethical argumentation in decisions on participation of vulnerable patients in clinical research

BACKGROUND

The participation of vulnerable patients in clinical research poses apparent ethical dilemmas. Depending on the nature of the vulnerability, their participation may challenge the ethical principles of autonomy, non-maleficence, or justice. On the other hand, non-participation may preclude the building of a knowledge base that is a prerequisite for defining the optimal clinical management of vulnerable patients. Such clinical uncertainty may also incur substantial economic costs.

MAIN TEXT

We present the participation of pre-menopausal women with atrial fibrillation in trials of novel oral anticoagulant drugs as a case study. Due to their non-participation in pivotal trials, it is uncertain whether for them, the risks that are associated with these drugs are outweighed by the advantages compared with conventional treatment. We addressed the question whether research of this new class of drugs in this subgroup would be appropriate from both, an ethical as well an economic perspective. We used the method of specifying norms as a wider framework to resolve the apparent ethical dilemma, while incorporating the question whether research of oral anticoagulants in premenopausal women with atrial fibrillation can be justified on economic grounds. For the latter, the results of a value-of-information analysis were used.

CONCLUSIONS

Further clinical research on NOACs in premenopausal women with atrial fibrillation can be justified on both, ethical and economic grounds. Addressing apparent ethical dilemmas by invoking a method such as specifying norms can improve the quality of public practical reasoning. As such, the method should also prove valuable to committees that have formally been granted the authority to review trial protocols and proposals for scientific research.

Comparison of Prescribing Practices with Direct Acting Oral Anticoagulant Protocols

BACKGROUND

The goal of anticoagulation management programs is to prevent thrombosis while minimizing the risks of hemorrhage. Direct acting oral anticoagulants (DOACs) selectively inhibit coagulation proteins to inhibit thrombosis. Previous studies suggest patient monitoring and education provided through anticoagulation services enhance adherence and decrease adverse outcomes in patients receiving DOAC therapy.

OBJECTIVE

The objectives of this study were to describe DOAC prescribing adherence to anticoagulation service protocols and to observe whether enrollment in an anticoagulation service resulted in greater prescribing adherence to DOAC protocols.

METHODS

A retrospective cohort study evaluated all initial prescriptions of apixaban, dabigatran, and rivaroxaban at Marshfield Clinic from 19 October 2010 to 21 August 2014. Three algorithms analyzed patient and prescription data extracted from the organization's electronic health record and classified prescriptions as per protocol or not per protocol. The algorithms classified not per protocol prescriptions as off-label indication, renal impairment [estimated glomerular filtration rate (eGFR) <30 ml/min], hepatic impairment (rivaroxaban and apixaban), advanced age >74 years (dabigatran), dose too low, or dose too high. The analysis assessed whether enrollment in the Marshfield Clinic Anticoagulation Service DOAC monitoring process was associated with increased adherence to protocols.

RESULTS

In aggregate, 72% of apixaban prescriptions, 52% of dabigatran prescriptions, and 70% of rivaroxaban prescriptions were per protocol. Off-label indications and dosage too low were the most common not per protocol reasons for apixaban and rivaroxaban prescriptions. Age ≥75 years and off-label indication were the most common not per protocol reasons for dabigatran prescriptions. Enrollment in the anticoagulation service process was not associated with increased adherence to protocols.

CONCLUSION

A significant proportion of DOAC prescriptions did not adhere to protocol expectations. While enrollment in DOAC management through the Marshfield Clinic Anticoagulation Service was not associated with increased adherence to protocols, opportunities exist to optimize DOAC prescribing. Defining ideal DOAC management requires additional research.

Emerging therapeutic uses of direct-acting oral anticoagulants: An evidence-based perspective

Direct-acting oral anticoagulants (DOACs) were claimed to cause a potential paradigm shift in the therapeutic scenario of patients requiring short- and long-term anticoagulation, by virtue of their pharmacological properties, perceived as innovative. The evidence gathered so far (from pre-approval pivotal trials to real-world post-marketing observational data) consistently confirmed that DOACs are overall comparable to vitamin-K antagonists (VKAs) in terms of safety, efficacy and effectiveness and unequivocally documented a consistent and clinically relevant reduced risk of intracranial bleeding in the settings of non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE). Interestingly, two parallel paths can be identified in the current research scenario: A) in the aforementioned consolidated therapeutic indications, an innovative approach is directed towards tailored treatment strategies, to identify patients most likely to benefit from one of the different anticoagulant drugs, in particular subpopulations at increased risk of adverse events (e.g., bleeding); B) in unconventional settings, DOACs are gaining interest for potential use in emerging diseases characterized by arterial and venous thromboembolic risk. In these scenarios, the risk-benefit profile of DOACs, as compared to VKAs or heparins, is less defined. The aim of this review is to critically assess the body of evidence underlying emerging therapeutic uses of DOACs (e.g., heparin-induced thrombocytopenia, anti-phospholipid antibody syndrome), including evolving issues in special populations (e.g., patients with VTE and cancer or cirrhosis). This will be achieved by analyzing the strength (i.e., systematic reviews, randomized clinical trials, observational studies, case report/series) and consistency (i.e., concordance) of both published and unpublished evidence registered in major public repositories.

Analytical Management of Patients Undergoing Oral Anticoagulant Therapy Could Have a Strong Impact on Clinical Outcomes: A Follow-up Study

Introduction

Oral anticoagulant therapy, such as vitamin K antagonists (VKAs), is prominent for the prevention of cerebral ischemic stroke or systemic embolism and all-cause mortality in patients with atrial fibrillation, venous thromboembolism, and mechanical or biological valve. VKA treatment requires monitoring of the international normalized ratio (INR) in order to maintain it in a therapeutic range, avoiding side effects, the main and most significant of which is bleeding. The aim of the present study was to evaluate the event rates of several clinical composite outcomes, such as bleeding, thromboembolic events, and all-cause death.

Methods

We compared three organizational models distinguished by a total (from 1 January to 31 December 2015 in which PT/INR analysis with the relative internal and external quality controls was performed by the surveillance center) or partial (from 15 January to 15 July 2016 and from 15 August to 15 November 2016, in which the surveillance center had the ability to view only the PT/INR results or all patients analyses, including blood count, creatinine, liver enzymes, etc., respectively) analytical patient management. The present longitudinal follow-up study included 1225 patients, recruited from 1 January 2015 to 15 November 2016 at a surveillance center for the prevention of cerebral ischemic stroke and systemic embolism in Chieti (Italy).

Results

The results show a significant rise of the incidence rate ratio in patients undergoing VKA treatment during the period 15 January to 15 July 2016 compared to the previous one regarding total bleeding, especially for minor bleeding and digestive bleeding; thromboembolic events; and all-death cause.

Conclusions

These findings show that analytical and clinical data and information should be under the direct supervision and responsibility of the surveillance center. In fact, this approach seems to highlight the best results in terms of safety and therapeutic effectiveness.

12/15-Lipoxygenase Inhibition or Knockout Reduces Warfarin-Associated Hemorrhagic Transformation After Experimental Stroke

BACKGROUND AND PURPOSE

For stroke prevention, patients with atrial fibrillation typically receive oral anticoagulation. The commonly used anticoagulant warfarin increases the risk of hemorrhagic transformation (HT) when a stroke occurs; tissue-type plasminogen activator treatment is therefore restricted in these patients. This study was designed to test the hypothesis that 12/15-lipoxygenase (12/15-LOX) inhibition would reduce HT in warfarin-treated mice subjected to experimental stroke.

METHODS

Warfarin was dosed orally in drinking water, and international normalized ratio values were determined using a Coaguchek device. C57BL6J mice or 12/15-LOX knockout mice were subjected to transient middle cerebral artery occlusion with 3 hours severe ischemia (model A) or 2 hours ischemia and tissue-type plasminogen activator infusion (model B), with or without the 12/15-LOX inhibitor ML351. Hemoglobin was determined in brain homogenates, and hemorrhage areas on the brain surface and in brain sections were measured. 12/15-LOX expression was detected by immunohistochemistry.

RESULTS

Warfarin treatment resulted in reproducible increased international normalized ratio values and significant HT in both models. 12/15-LOX knockout mice suffered less HT after severe ischemia, and ML351 reduced HT in wild-type mice. When normalized to infarct size, ML351 still independently reduced hemorrhage. HT after tissue-type plasminogen activator was similarly reduced by ML351.

CONCLUSIONS

In addition to its benefits in infarct size reduction, 12/15-LOX inhibition also may independently reduce HT in warfarin-treated mice. ML351 should be further evaluated as stroke treatment in anticoagulated patients suffering a stroke, either alone or in conjunction with tissue-type plasminogen activator.

Risk-Benefit Profile of Direct-Acting Oral Anticoagulants in Established Therapeutic Indications: An Overview of Systematic Reviews and Observational Studies

Since 2008, the direct-acting oral anticoagulants (DOACs) have expanded the therapeutic options of cardiovascular diseases with recognized clinical and epidemiological impact, such as non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE), and also in the preventive setting of orthopedic surgical patients. The large body of evidence, not only from pivotal clinical trials but also from 'real-world' postmarketing observational findings (e.g. analytical epidemiological studies and registry data) gathered to date allow for a first attempt at verifying a posteriori whether or not the pharmacological advantages of the DOACs actually translate into therapeutic innovation, with relevant implications for clinicians, regulators and patients. This review aims to synthesize the risk-benefit profile of DOACs in the aforementioned consolidated indications through an 'evidence summary' approach gathering the existent evidence-based data, particularly systematic reviews with meta-analyses of randomized controlled trials, as well as observational studies, comparing DOACs with vitamin K antagonists. Clinical evidence will be discussed and compared with major international guidelines to identify whether an update is needed. Controversial clinically relevant safety issues will be also examined in order to highlight current challenges and unsettled questions (e.g. actual bleeding risk in susceptible populations). It is anticipated that the large number of publications on NVAF or VTE (44 systematic reviews with meta-analyses and 12 observational studies retained in our analysis) suggests the potential existence of overlapping studies and calls for common criteria to qualitatively and quantitatively assess discordances, thus guiding future research.

How I use anticoagulation in atrial fibrillation

Atrial fibrillation is the most common cardiac arrhythmia and conveys a significant risk of morbidity and mortality due to related stroke and systemic embolism. Oral anticoagulation (OAC) is the mainstay of thromboembolism prevention, and management of anticoagulation can be challenging. For patients without significant valvular disease, decisions around anticoagulation therapy are first based on the presence of additional stroke risk factors, as measured by the CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥75, diabetes, prior stroke or transient ischemic attack, vascular disease, age 65-74, and sex category [female]) score. Patients with increased CHA₂DS₂-VASc scores (by regional guidelines) should next be evaluated to determine if they are candidates for non-vitamin K antagonist oral anticoagulant (NOAC) therapy. This should focus on assessment of concomitant valve disease and/or impaired renal function. In eligible patients, the cumulative data support a preference for NOACs over warfarin, as NOACs appear safer and more effective as a group. However, there are no direct, randomized comparisons between NOACs, and therefore, selecting among them can be difficult. In addition, important patient groups remain underrepresented in major clinical trials, and their management is often left to clinician judgment. Data from emerging clinical trials will help guide physicians; however, patient engagement in decisions regarding OAC management will remain vital to ensuring appropriate balance of risks and optimizing health outcomes.

Evaluation of Bleeding Events Requiring Hospitalization in Patients With Atrial Fibrillation Receiving Dabigatran, Warfarin, or Antiplatelet Therapy

Objective:

To determine the incidence and severity of bleeding events requiring hospitalization among patients with atrial fibrillation (AF) receiving anticoagulants (dabigatran or warfarin) or antiplatelet agents (eg, aspirin and clopidogrel).

Methods:

This was a single-center, retrospective cohort study involving 1494 patients with AF hospitalized from November 1, 2010, to November 1, 2011, with prior warfarin, dabigatran, or antiplatelet therapy.

Results:

Overall bleeding events in the dabigatran group compared to the warfarin group were 24% and 12%, respectively ( P = .004). Of these events, individually, there were no significant differences in major (56% vs 58%, P = .88), life-threatening (25% vs 36%, P = .38), or minor bleeding (44% vs 42%, P = .06). Gastrointestinal (GI) bleeding occurred more in the dabigatran group compared to the warfarin group ( P = .02). Intracranial bleeding occurred in 15% of patients in the warfarin group and did not occur at all in the dabigatran group. Warfarin patients had significantly more overall bleeding events compared to antiplatelet therapy ( P < .001), with an increasing trend seen in major bleeding ( P = .06). GI bleeding, however, favored the warfarin group over the antiplatelet group (48% vs 73%, P = .04).

Conclusion:

Anticoagulation with dabigatran was associated with an overall increased occurrence of bleeding requiring hospital admission compared to warfarin. GI bleeding was more prevalent with dabigatran and antiplatelets than with warfarin. There were more intracranial hemorrhages seen in the warfarin group.

Societal Costs of First-Incident Ischemic Stroke in Patients with Atrial Fibrillation-A Danish Nationwide Registry Study

BACKGROUND

Oral anticoagulation therapy reduces the risk of ischemic stroke in patients with atrial fibrillation (AF). However, more data on the costs of stroke in patients with AF are needed to assess how this therapy affects societal costs.

OBJECTIVES

The aim of the study was to estimate the average 3-year societal costs of first-incident ischemic stroke in Danish patients with AF, including costs of health care, social care services, and productivity loss.

METHODS

The study was designed as an incidence-based cost-of-illness study covering the entire Danish population. All patients with a hospital diagnosis of AF were identified, and propensity score-matched analyses were used to estimate costs attributable to first-incident stroke among patients with AF in the period 2002 to 2012. All data were obtained from nationwide registries.

RESULTS

A total of 21,673 patients with AF were identified with a first-incident stroke. The average 3-year costs attributable to stroke were US $30,925 per patient (present value) corresponding to US $19,989 in the incidence year and US $7,683 and US $5,176 1 and 2 years after the stroke, respectively. Health care accounted for 66% of the 3-year costs, with hospitalizations in the incidence year as the main cost driver. After the incidence year, costs of social care services exceeded health care costs. Sensitivity analyses showed that the cost estimates were relatively robust.

CONCLUSIONS

The societal costs of first-incident stroke in patients with AF are substantial. This new evidence can be valuable as an input for decision making regarding the treatment of AF and prevention of future strokes.

Direct oral anticoagulants: New drugs with practical problems. How can nurses help prevent patient harm?

The safe use of anticoagulants requires a delicate balance between the risk of bleeding and the risk of thrombosis, particularly in drug-sensitive patients, such as older people. Recently-marketed "direct oral anticoagulants" are now being increasingly prescribed and administered in the hospital setting. Direct oral anticoagulants have pharmacological properties that are often unpredictable, and inter-patient variability in drug response is high. Therefore, people often require meticulous review and planning to ensure they receive optimal dosing and monitoring. The multidisciplinary medication management of those receiving these drugs needs to be effectively coordinated to reduce the risk of patient harm. All clinical staff, including nurses, doctors, and pharmacists, should be competent in the pharmacology of these drugs, and know which people require individualized care plans. In this study, we introduced important concepts via the use of case studies developed from commonly-seen scenarios at our quaternary hospital. In particular, the important role of nurses in ensuring patient safety in the periprocedural setting is highlighted.

Management of antithrombotic therapy during cardiac implantable device surgery

Anticoagulants are commonly used drugs that are frequently encountered during device placement. Deciding when to halt or continue the use of anticoagulants is a balance between the risks of thromboembolism versus bleeding. Patients taking warfarin with a high risk of thromboembolism should continue to take their warfarin without interruption during device placement while ensuring their international normalized ratio remains below 3. For patients who are taking warfarin and have low risk of thromboembolism, either interrupted or continued warfarin may be used, with no evidence to clearly support either strategy. There is little evidence to support continuing direct acting oral anticoagulants (DOACs) for device implantation. The timing of halting these medications depends largely on renal function. If bleeding occurs, warfarin׳s anticoagulation effect is reversible with vitamin K and activated prothrombin complex concentrate. There are no DOAC reversal agents currently available, but some are under development. Regarding antiplatelet agents, aspirin alone can be safely continued while clopidogrel alone may also be continued, but with a slightly higher bleeding risk. Dual antiplatelet therapy for bare-metal stent/drug-eluting stent implanted within 4 weeks/6 months, respectively, should be continued due to high risk of stent thrombosis; however, if they are implanted after this period, then clopidogrel can be halted 5 days before the procedure and resumed soon after, while aspirin is continued. If the patient is taking both aspirin and warfarin, aspirin should be halted 5 days prior to the procedure, while warfarin is continued.

Atrial fibrillation ablation and left appendage closure in heart failure patients

PURPOSE OF REVIEW

Patients with atrial fibrillation and heart failure experience an increased morbidity and mortality from the hemodynamic consequences of atrial fibrillation and an increased stroke risk. Consequently, there has been increased attention to procedural alternatives to pharmacologic rhythm control and anticoagulation for stroke prevention. This review aims to evaluate the evidence for atrial fibrillation ablation and left atrial appendage closure in heart failure patients.

RECENT FINDINGS

Several randomized control trials and systematic reviews demonstrate the safety and efficacy of atrial fibrillation ablation in patients with heart failure and left ventricular systolic dysfunction. In multiple trials, these patients have shown clinical benefit from atrial fibrillation ablation including improved left ventricular systolic function, quality of life, and clinical heart failure symptoms. The evidence of clinical benefit of atrial fibrillation ablation in heart failure patients with preserved ejection fraction remains limited. Only a handful of randomized controlled trials have been performed evaluating left atrial appendage closure, and there is insufficient data regarding the safety and efficacy of these procedures in heart failure patients.

SUMMARY

Atrial fibrillation ablation in heart failure patients remains well tolerated with an overall efficacy comparable to atrial fibrillation ablation in patients without heart failure. There is consistent evidence for the clinical benefit of atrial fibrillation ablation in heart failure patients with left ventricular systolic dysfunction and limited evidence for atrial fibrillation ablation in heart failure patients with preserved ejection fraction. Currently, there is insufficient data regarding the safety and efficacy of left atrial appendage closure devices in heart failure patients.

Effect of heart rate control on coagulation status in patients of rheumatic mitral stenosis with atrial fibrillation--A pilot study

BACKGROUND AND AIM OF STUDY

Systemic thromboembolism is a major complication in patients of mitral stenosis (MS) with atrial fibrillation (AF) due to induction of hypercoagulable state. The aim was to assess the relationship, if any, between control of ventricular rate and systemic coagulation factors.

METHOD

70 patients of moderate to severe MS in AF were studied. 35 patients with average heart rate > 100 beats/min over a 24 hour period assessed by Holter monitoring were considered as having a uncontrolled ventricular rate (Group A) and those with average heart rate ≤ 100 beats/min as controlled ventricular rate (Group B). 30 healthy volunteers acted as controls.

RESULTS

Plasma concentration of prothrombin fragment 1+2 (PF1+2) 6600 pmol/ml [interquartile range (IQR) 5400.0-9500], thrombin antithrombin III 22.0 ng/ml [IQR 18.6-28.0], and plasminogen activator inhibitor 46.8 ng/ml [IQR 44.0-54.0] were elevated in Group A as compared to Group B (5400 pmol/ml [IQR 3600-7700] p = 0.009, 16.0 ng/ml [IQR 11.0-18.5] p<0.001, and 25.8 ng/ml [IQR 20.9-34.4] p < 0.001), respectively. A significant correlation was found between heart rate and all three coagulation markers. Multivariate multiple regression analysis showed only heart rate to be an independent predictor of systemic coagulation activation and risk of thrombus formation.

CONCLUSION

Control of ventricular rate in subjects of MS with AF produces significant reduction in the activation of the coagulation system and may decrease risk of thrombosis.

Adherence to oral anticoagulants in patients with atrial fibrillation-a population-based retrospective cohort study linking health information systems in the Valencia region, Spain: a study protocol

INTRODUCTION

Adherence to oral anticoagulation (OAC) treatment, vitamin K antagonists or new oral anticoagulants, is an essential element for effectiveness. Information on adherence to OAC in atrial fibrillation (AF) and the impact of adherence on clinical outcomes using real-world data barely exists. We aim to describe the patterns of adherence to OAC over time in patients with AF, estimate the associated factors and their impact on clinical events, and assess the same issues with conventional measures of primary and secondary adherence-proportion of days covered (PDC) and persistence-in routine clinical practice.

METHODS AND ANALYSIS

This is a population-based retrospective cohort study including all patients with AF treated with OAC from 2010 to date in Valencia, Spain; data will be obtained from diverse electronic records of the Valencia Health Agency.

PRIMARY OUTCOME MEASURE

adherence trajectories.

SECONDARY OUTCOMES

(1) primary non-adherence; (2) secondary adherence: (a) PDC, (b) persistence. Clinical outcomes: hospitalisation for haemorrhagic or thromboembolic events and death during follow-up.

ANALYSIS

(1) description of baseline characteristics, adherence patterns (trajectory models or latent class growth analysis models) and conventional adherence measures; (2) logistic or Cox multivariate regression models, to assess the associations between adherence measures and the covariates, and logistic multinomial regression models, to identify characteristics associated with each trajectory; (3) Cox proportional hazard models, to assess the relationship between adherence and clinical outcomes, with propensity score adjustment applied to further control for potential confounders; (4) to estimate the importance of different healthcare levels in the variations of adherence, logistic or Cox multilevel regression models.

ETHICS AND DISSEMINATION

This study has been approved by the corresponding Clinical Research Ethics Committee. We plan to disseminate the project's findings through peer-reviewed publications and presentations at relevant health conferences. Policy reports will also be prepared in order to promote the translation of our findings into policy and clinical practice.

Comparison of the short-term risk of bleeding and arterial thromboembolic events in nonvalvular atrial fibrillation patients newly treated with dabigatran or rivaroxaban versus vitamin K antagonists: a French nationwide propensity-matched cohort study

Supplemental Digital Content is available in the text.

Background—

The safety and effectiveness of non–vitamin K antagonist (VKA) oral anticoagulants, dabigatran or rivaroxaban, were compared with VKA in anticoagulant-naive patients with nonvalvular atrial fibrillation during the early phase of anticoagulant therapy.

Methods and Results—

With the use of the French medico-administrative databases (SNIIRAM and PMSI), this nationwide cohort study included patients with nonvalvular atrial fibrillation who initiated dabigatran or rivaroxaban between July and November 2012 or VKA between July and November 2011. Patients presenting a contraindication to oral anticoagulants were excluded. Dabigatran and rivaroxaban new users were matched to VKA new users by the use of 1:2 matching on the propensity score. Patients were followed for up to 90 days until outcome, death, loss to follow-up, or December 31 of the inclusion year. Hazard ratios of hospitalizations for bleeding and arterial thromboembolic events were estimated in an intent-to-treat analysis using Cox regression models. The population was composed of 19 713 VKA, 8443 dabigatran, and 4651 rivaroxaban new users. All dabigatran- and rivaroxaban-treated patients were matched to 16 014 and 9301 VKA-treated patients, respectively. Among dabigatran-, rivaroxaban-, and their VKA-matched–treated patients, 55 and 122 and 31 and 68 bleeding events and 33 and 58 and 12 and 28 arterial thromboembolic events were observed during follow-up, respectively. After matching, no statistically significant difference in bleeding (hazard ratio, 0.88; 95% confidence interval, 0.64–1.21) or thromboembolic (hazard ratio, 1.10; 95% confidence interval, 0.72–1.69) risk was observed between dabigatran and VKA new users. Bleeding (hazard ratio, 0.98; 95% confidence interval, 0.64–1.51) and ischemic (hazard ratio, 0.93; 95% confidence interval, 0.47–1.85) risks were comparable between rivaroxaban and VKA new users.

Conclusions—

In this propensity-matched cohort study, our findings suggest that physicians should exercise caution when initiating either non-VKA oral anticoagulants or VKA in patients with nonvalvular atrial fibrillation.