Stroke Prevention for Patients with Atrial Fibrillation: Beyond the Guidelines

Chronic Overlapping Pain Conditions and Nociplastic Pain

Chronic Overlapping Pain Conditions (COPCs) are a subset of chronic pain conditions commonly comorbid with one another and more prevalent in women and assigned female at birth (AFAB) individuals. Pain experience in these conditions may better fit with a new mechanistic pain descriptor, nociplastic pain, and nociplastic type pain may represent a shared underlying factor among COPCs. We applied GenomicSEM common-factor genome wide association study (GWAS) and multivariate transcriptome-wide association (TWAS) analyses to existing GWAS output for six COPCs in order to find genetic variation associated with nociplastic type pain, followed by genetic correlation (linkage-disequilibrium score regression), gene-set and tissue enrichment analyses. We found 24 independent single nucleotide polymorphisms (SNPs), and 127 unique genes significantly associated with nociplastic type pain, and showed nociplastic type pain to be a polygenic trait with significant SNP-heritability. We found significant genetic overlap between multisite chronic pain and nociplastic type pain, and to a smaller extent with rheumatoid arthritis and a neuropathic pain phenotype. Tissue enrichment analyses highlighted cardiac and thyroid tissue, and gene set enrichment analyses emphasized potential shared mechanisms in cognitive, personality, and metabolic traits and nociplastic type pain along with distinct pathology in migraine and headache. We use a well-powered network approach to investigate nociplastic type pain using existing COPC GWAS output, and show nociplastic type pain to be a complex, heritable trait, in addition to contributing to understanding of potential mechanisms in development of nociplastic pain.

Atrial Fibrillation Recurrence in Patients With Transient New-Onset Atrial Fibrillation Detected During Hospitalization for Noncardiac Surgery or Medical Illness : A Matched Cohort Study

BACKGROUND

Atrial fibrillation (AF) is often detected for the first time in patients who are hospitalized for another reason. Long-term risks for AF recurrence in these patients are unclear.

OBJECTIVE

To estimate risk for AF recurrence in patients with new-onset AF during a hospitalization for noncardiac surgery or medical illness compared with a matched population without AF.

DESIGN

Matched cohort study. (ClinicalTrials.gov: NCT03221777).

SETTING

Three academic hospitals in Hamilton, Ontario, Canada.

PARTICIPANTS

The study enrolled patients hospitalized for noncardiac surgery or medical illness who had transient new-onset AF. For each participant, an age- and sex-matched control participant with no history of AF from the same hospital ward was recruited. All participants left the hospital in sinus rhythm.

MEASUREMENTS

14-day electrocardiographic (ECG) monitor at 1 and 6 months and telephone assessment at 1, 6, and 12 months. The primary outcome was AF lasting at least 30 seconds on the monitor or captured by ECG 12-lead during routine care at 12 months.

RESULTS

Among 139 participants with transient new-onset AF (70 patients with medical illness and 69 surgical patients) and 139 matched control participants, the mean age was 71 years (SD, 10), the mean CHA2DS2-VASc score was 3.0 (SD, 1.5), and 59% were male. The median duration of AF during the index hospitalization was 15.8 hours (IQR, 6.4 to 49.6 hours). After 1 year, recurrent AF was detected in 33.1% (95% CI, 25.3% to 40.9%) of participants in the transient new-onset AF group and 5.0% (CI, 1.4% to 8.7%) of matched control participants; after adjustment for the number of ECG monitors worn and for baseline clinical differences, the adjusted relative risk was 6.6 (CI, 3.2 to 13.7). After exclusion of participants who had electrical or pharmacologic cardioversion during the index hospitalization (n = 40) and their matched control participants and limiting to AF events detected by the patch ECG monitor, recurrent AF was detected in 32.3% (CI, 23.1% to 41.5%) of participants with transient new-onset AF and 3.0% (CI, 0% to 6.4%) of matched control participants.

LIMITATIONS

Generalizability is limited, and the study was underpowered to evaluate subgroups and clinical predictors.

CONCLUSION

Among patients who have transient new-onset AF during a hospitalization for noncardiac surgery or medical illness, approximately 1 in 3 will have recurrent AF within 1 year.

PRIMARY FUNDING SOURCE

Peer-reviewed grants.

Post-operative atrial fibrillation after cardiac surgery: Challenges throughout the patient journey

Atrial fibrillation (AF) is the most common complication of cardiac surgery, occurring in up to half of patients. Post-operative AF (POAF) refers to new-onset AF in a patient without a history of AF that occurs within the first 4 weeks after cardiac surgery. POAF is associated with short-term mortality and morbidity, but its long-term significance is unclear. This article reviews existing evidence and research challenges for the management of POAF in patients who have had cardiac surgery. Specific challenges are discussed in four phases of care. Pre-operatively, clinicians need to be able to identify high-risk patients, and initiate prophylaxis to prevent POAF. In hospital, when POAF is detected, clinicians need to manage symptoms, stabilize hemodynamics and prevent increases in length of stay. In the month after discharge, the focus is on minimizing symptoms and preventing readmission. Some patients require short term oral anticoagulation for stroke prevention. Over the long term (2-3  months after surgery and beyond), clinicians need to identify which patients with POAF have paroxysmal or persistent AF and can benefit from evidence-based therapies for AF, including long-term oral anticoagulation.

Impact of Cardiovascular Diseases on Ischemic Stroke Outcomes

Stroke induces complex pathological cascades in the affected brain area, leading to brain injury and functional disability. To fight against cerebral ischemia/reperfusion-induced neuronal death, numerous neuroprotective strategies and reagents have been studied. However, translation of these neuroprotective drugs to clinical trials has been unsuccessful. To date, the tissue plasminogen activator is still the only FDA-approved drug for treating ischemic stroke. Thus, it is obligatory to identify and validate additional therapeutic strategies for stroke. A stroke rarely occurs without any other pathophysiological condition; but instead, it often has multi-morbidity conditions, one of which is cardiac disease. Indeed, up to half of the stroke cases are associated with cardiac and large artery diseases. As an adequate blood supply is essential for the brain to maintain its normal function, any pathophysiological alterations in the heart are frequently implicated in stroke outcomes. In this review, we summarize some of the cardiovascular factors that influence stroke outcomes and propose that considering these factors in designing stroke therapies should enhance success in clinical trials. We also highlight the recent advances regarding the potential effect of protein aggregates in a peripheral organ, such as in the heart, on ischemic stroke-caused brain injury and functional recovery. Including these and other comorbidity factors in the future therapeutic strategy designs should facilitate translational success toward developing effective combinational therapies for the disorder.

New-Onset Atrial Fibrillation After Cardiac Surgery is a Significant Risk Factor for Long-Term Stroke: An Eight-Year Prospective Cohort Study

OBJECTIVES

This study sought to determine the incidence and significance of new-onset atrial fibrillation as a risk factor for long-term stroke and mortality after cardiac surgery.

DESIGN

A prospective cohort study.

SETTING

Two large tertiary public hospitals.

PARTICIPANTS

The study comprised 3008 patients who underwent coronary artery bypass grafting and/or valve surgery from 2008 to 2012.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

New-onset atrial fibrillation was analyzed as a risk factor for postoperative stroke using a multivariate logistic regression model after adjustment for potential confounders. A Cox regression model with time-dependent variables was used to analyze relationships between new-onset atrial fibrillation and postoperative survival. New-onset atrial fibrillation was detected in 573 (19.0%) patients. Stroke occurred in 234 (7.8%) patients during the mean postoperative follow-up period of six ± two years. The incidence of postoperative stroke in patients with new-onset atrial fibrillation (9.9%) and patients with both preoperative and postoperative atrial fibrillation (13.8%) was higher than in patients with no atrial fibrillation (6.8%) (p = 0.002). New-onset atrial fibrillation (odds ratio, 1.53; 95% confidence interval [CI], 1.08-2.18; p = 0.017) was identified as an independent risk factor for postoperative stroke. A total of 518 (17.2%) mortalities occurred within the mean postoperative follow-up period of eight ± two years. New-onset atrial fibrillation was associated with shorter survival (hazard ratio, 1.49; 95% CI, 1.22-1.81; p < 0.001) compared with patients with no atrial fibrillation.

CONCLUSIONS

New-onset atrial fibrillation is a significant risk factor for long-term stroke and mortality after cardiac surgery. Close monitoring and treatment of this condition may be necessary to reduce the risk of postoperative stroke and mortality.

New-onset atrial fibrillation incidence and associated outcomes in the medical intensive care unit

BACKGROUND

In patients with critical medical illness, data regarding new-onset atrial fibrillation (NOAF) is relatively sparse. This study examines the incidence, associated risk factors, and associated outcomes of NOAF in patients in the medical intensive care unit (MICU).

METHODS

This single-center retrospective observational cohort study included 2234 patients with MICU stays in 2018. An automated extraction process using ICD-10 codes, validated by a 196-patient manual chart review, was used for data collection. Demographics, medications, and risk factors were collected. Multiple risk scores were calculated for each patient, and AF recurrence was also manually extracted. Length of stay, mortality, and new stroke were primary recorded outcomes.

RESULTS

Two hundred and forty one patients of the 2234 patient cohort (11.4%) developed NOAF during their MICU stay. NOAF was associated with greater length of stay in the MICU (5.84 vs. 3.52 days, p < .001) and in the hospital (15.7 vs. 10.9 days, p < .001). Patients with NOAF had greater odds of hospital mortality (odds ratio (OR) = 1.92, 95% confidence interval (CI) 1.34-2.71, p < .001) and 1-year mortality (OR = 1.37, 95% CI 1.02-1.82, p = .03). CHARGE-AF scores performed best in predicting NOAF (area under the curve (AUC) 0.691, p < .001).

CONCLUSIONS

The incidence of NOAF in this MICU cohort was 11.4%, and NOAF was associated with a significant increase in hospital LOS and mortality. Furthermore, the CHARGE-AF score performed best in predicting NOAF.

Incidence and recurrence of new-onset atrial fibrillation detected during hospitalization for non-cardiac surgery: a systematic review and meta-analysis

PURPOSE

This systematic review aimed to summarize reports of the incidence and long-term recurrence of new-onset atrial fibrillation (AF) associated with non-cardiac surgery.

SOURCES

We searched CENTRAL, MEDLINE and EMBASE from inception to November 2019. We included studies that reported on the incidence of new-onset perioperative AF during hospitalization for non-cardiac surgery and/or AF recurrence in such patients following discharge. Reviewers screened articles and abstracted data independently and in duplicate. We assessed study quality by appraising methodology for collecting AF history, incident AF during hospitalization, and AF recurrence after discharge.

PRINCIPAL FINDINGS

From 39,233 citations screened, 346 studies that enrolled a total of 5,829,758 patients met eligibility criteria. Only 27 studies used prospective, continuous inpatient electrocardiographic (ECG) monitoring to detect incident AF. Overall, the incidence of postoperative AF during hospitalization ranged from 0.004 to 50.3%, with a median [interquartile range] of 8.7 [3.8-15.0]%. Atrial fibrillation incidence varied with type of surgery. Prospective studies using continuous ECG monitoring reported significantly higher incidences of AF than those that did not (13.9% vs 1.9%, respectively; P < 0.001). A total of 13 studies (25,726 patients) with follow-up up to 5.4 years reported on AF recurrence following hospital discharge; only one study used a prospective systematic monitoring protocol. Recurrence rates ranged from 0 to 37.3%.

CONCLUSIONS

Rates of AF incidence first detected following non-cardiac surgery and long-term AF recurrence vary markedly. Differences in the intensity of ECG monitoring and type of surgery may account for this variation.

TRIAL REGISTRATION

PROSPERO (CRD42017068055); registered 1 September 2017.

Gut Microbiota and the Quality of Oral Anticoagulation in Vitamin K Antagonists Users: A Review of Potential Implications

The efficacy and safety of vitamin K antagonists (VKAs) as oral anticoagulants (OACs) depend on the quality of anticoagulation control, as reflected by the mean time in therapeutic range (TTR). Several factors may be involved in poor TTR such as comorbidities, high inter-individual variability, interacting drugs, and non-adherence. Recent studies suggest that gut microbiota (GM) plays an important role in the pathogenesis of cardiovascular diseases, but the effect of the GM on anticoagulation control with VKAs is unknown. In the present review article, we propose different mechanisms by which the GM could have an impact on the quality of anticoagulation control in patients taking VKA therapy. We suggest that the potential effects of GM may be mediated first, by an indirect effect of metabolites produced by GM in the availability of VKAs drugs; second, by an effect of vitamin K-producing bacteria; and finally, by the structural modification of the molecules of VKAs. Future research will help confirm these hypotheses and may suggest profiles of bacterial signatures or microbial metabolites, to be used as biomarkers to predict the quality of anticoagulation. This could lead to the design of intervention strategies modulating gut microbiota, for example, by using probiotics.

Economic evaluation of extended electrocardiogram monitoring for atrial fibrillation in patients with cryptogenic stroke

BACKGROUND

Timely identification of occult atrial fibrillation following cryptogenic stroke facilitates consideration of oral anticoagulation therapy. Extended electrocardiography monitoring beyond 24 to 48 h Holter monitoring improves atrial fibrillation detection rates, yet uncertainty remains due to upfront costs and the projected long-term benefit. We sought to determine the cost-effectiveness of three electrocardiography monitoring strategies in detecting atrial fibrillation after cryptogenic stroke.

METHODS

A decision-analytic Markov model was used to project the costs and outcomes of three different electrocardiography monitoring strategies (i.e. 30-day electrocardiography monitoring, three-year implantable loop recorder monitoring, and conventional Holter monitoring) in acute stroke survivors without previously documented atrial fibrillation.

RESULTS

The lifetime discounted costs and quality-adjusted life years were $206,385 and 7.77 quality-adjusted life years for conventional monitoring, $207,080 and 7.79 quality-adjusted life years for 30-day extended electrocardiography monitoring, and $210,728 and 7.88 quality-adjusted life years for the implantable loop recorder strategy. Additional quality-adjusted life years could be attained at a more favorable incremental cost per quality-adjusted life year with the implantable loop recorder strategy, compared with the 30-day electrocardiography monitoring strategy, thereby eliminating the 30-day strategy by extended dominance. The implantable loop recorder strategy was associated with an incremental cost per quality-adjusted life year gained of $40,796 compared with conventional monitoring. One-way sensitivity analyses indicated that the model was most sensitive to the rate of recurrent ischemic stroke.

CONCLUSIONS

An implantable loop recorder strategy for detection of occult atrial fibrillation in patients with cryptogenic stroke is more economically attractive than 30-day electrocardiography monitoring compared to conventional monitoring and is associated with a cost per quality-adjusted life year gained in the range of other publicly funded therapies. The value proposition is improved when considering patients at the highest risk of recurrent ischemic stroke. However, the implantable loop recorder strategy is associated with increased health care costs, and the opportunity cost of wide scale implementation must be considered.

Population-Based Screening for Atrial Fibrillation

Atrial fibrillation (AF) is a common and morbid arrhythmia. Stroke is a major hazard of AF and may be preventable with oral anticoagulation. Yet since AF is often asymptomatic, many individuals with AF may be unaware and do not receive treatment that could prevent a stroke. Screening for AF has gained substantial attention in recent years as several studies have demonstrated that screening is feasible. Advances in technology have enabled a variety of approaches to facilitate screening for AF using both medical-prescribed devices as well as consumer electronic devices capable of detecting AF. Yet controversy about the utility of AF screening remains owing to concerns about potential harms resulting from screening in the absence of randomized data demonstrating effectiveness of screening on outcomes such as stroke and bleeding. In this review, we summarize current literature, present technology, population-based screening considerations, and consensus guidelines addressing the role of AF screening in practice.

Cognitive Function and Atrial Fibrillation: From the Strength of Relationship to the Dark Side of Prevention. Is There a Contribution from Sinus Rhythm Restoration and Maintenance?

Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia with an increasing prevalence over time mainly because of population aging. It is well established that the presence of AF increases the risk of stroke, heart failure, sudden death, and cardiovascular morbidity. In the last two decades several reports have shown an association between AF and cognitive function, ranging from impairment to dementia. Ischemic stroke linked to AF is a well-known risk factor and predictor of cognitive decline. In this clinical scenario, the risk of stroke might be reduced by oral anticoagulation. However, recent data suggest that AF may be a predictor of cognitive impairment and dementia also in the absence of stroke. Cerebral hypoperfusion, reduced brain volume, microbleeds, white matter hyperintensity, neuroinflammation, and genetic factors have been considered as potential mechanisms involved in the pathogenesis of AF-related cognitive dysfunction. However, a cause-effect relationship remains still controversial. Consequently, no therapeutic strategies are available to prevent AF-related cognitive decline in stroke-free patients. This review will analyze the potential mechanisms leading to cognitive dysfunction in AF patients and examine the available data on the impact of a sinus rhythm restoration and maintenance strategy in reducing the risk of cognitive decline.

Stroke Risk in Atrial Fibrillation: Beyond the CHA2DS2-VASc Score

PURPOSE OF REVIEW

Stroke prevention is the cornerstone of atrial fibrillation (AF) management and the anticoagulation decision is currently based on CHA₂DS₂-VASc risk score. We discuss several novel risk factors besides those included in CHA₂DS₂-VASc score and alternative models for stroke prediction.

RECENT FINDINGS

Several clinical markers including obstructive sleep apnea and renal failure, laboratory markers like brain natriuretic peptide, imaging criteria including left atrial appendage morphology, spontaneous echo contrast, and coronary artery calcium score may predict stroke in AF patients. Addition of African American ethnicity to CHA₂DS₂-VASc score also improves stroke prediction in AF. Finally, novel models including TIMI-AF score, ATRIA score, and GARFIELD-AF scores have potential roles in risk stratification for stroke. While CHA₂DS₂-VASc score is the currently recommended risk stratification model for stroke prediction in AF, use of additional clinical, laboratory, imaging markers, ethnicity, and novel stroke prediction models may further assist in decision to anticoagulate the AF patient for stroke prevention.

Role of Obstructive Sleep Apnea in Cognitive Impairment

Obstructive sleep apnea (OSA) is a prevalent sleep related breathing disorder characterized by repetitive collapse of the upper airways leading to intermittent hypoxia and sleep disruption. Clinically relevant neurocognitive, metabolic and cardiovascular disease often occurs in OSA. Systemic hypertension, coronary artery disease, type 2 diabetes mellitus, cerebral vascular infarctions and atrial fibrillation are among the most often cited conditions with causal connections to OSA. Emerging science suggest that untreated and undertreated OSA increases the risk of developing cognitive impairment, including vascular dementia and neurodegenerative disorders, like Alzheimer’s disease. As with OSA, cardiovascular disease and type 2 diabetes mellitus, the incidence of dementia increases with age. Given our rapidly aging population, dementia prevalence will significantly increase. The aim of this treatise is to review current literature linking OSA to dementia and explore putative mechanisms by which OSA might facilitate the development and progression of dementia.

The Quality of Anticoagulation Therapy among Warfarin-Treated Patients with Atrial Fibrillation in a Primary Health Care Setting

Background and objectives: Long-term therapy with oral anticoagulants is recommended for stroke prevention in patients with atrial fibrillation (AF). This study evaluated the quality of anticoagulation therapy among warfarin-treated AF patients in selected primary health care centres in Lithuania. Materials and Methods: This was a retrospective study conducted in nine primary health care centres in Lithuania. Existing medical records of randomly selected adult patients with AF who were treated with warfarin for at least 12 months were reviewed and analysed. Physicians’ decisions to adjust warfarin dose were considered as consistent with the approved warfarin posology if warfarin dose was increased in case of international normalized ratio (INR) <2.0, decreased in case of INR >3.0 or unchanged in case of INR within 2.0 to 3.0. Results: The study population included 406 patients. The mean duration of treatment with warfarin was 5.4 years. The median number of INR measurements per patient per year was 8.0. More than half (57.3%) of available INR values were outside the target range, with 13.6% INR values being above 3.0 and 43.7% INR values—below 2.0. The median time in therapeutic range (TTR) was 40.0%; only 20% of patients had TTR of ≥65%. In about 40% of the cases with INR values outside the target range, no dose corrections were implemented. About 27% of decisions on warfarin dose adjustment were not consistent with the recommended warfarin posology. The median number of INR measurements was lower among patients living in urban areas, while the median TTR was significantly higher in urban patients than in rural patients. In the multivariate regression model, gender, HAS-BLED score and warfarin treatment duration were associated with a TTR of ≥65%. Conclusions: Anticoagulation control is suboptimal in routine clinical practice with a median TTR of 40%. Our findings suggest that there might be a room for improvement of anticoagulation control in primary care.

Stroke-prevention strategies in North American patients with atrial fibrillation: The GLORIA-AF registry program

Background

Antithrombotic prophylaxis with oral anticoagulation (OAC) substantially reduces stroke and mortality in patients with atrial fibrillation (AF).

Hypothesis

Analysis of data in the Global Registry on Long‐Term Antithrombotic Treatments in Patients With Atrial Fibrillation (GLORIA‐AF), an international, observational registry of patients with newly diagnosed AF, can identify factors associated with treatment decisions and outcomes.

Methods

Multivariable regression identified patient, physician, and temporal factors associated with OAC prescription, compared with management with antiplatelet drugs or no antithrombotic drugs in North American patients enrolled between November 2011 and February 2014.

Results

Of 3320 eligible patients (mean age, 71 ± 11 years; 1879 males with CHA₂DS₂‐VASc ≥1 and 1441 females with CHA₂DS₂‐VASc ≥2), 79.3%, 12.5%, and 7.4% received OAC, antiplatelet drugs, or no antithrombotic therapy, respectively. Of those prescribed OAC, 66.4% received non–vitamin K antagonist oral anticoagulation and 24.5% received concomitant therapy with antiplatelet drugs. Independent predictors of OAC therapy were nonparoxysmal AF (odds ratio, 95% confidence interval: 2.02, 1.56–2.63), prior stroke/transient ischemic attack (2.00, 1.37–2.92), specialist care (1.50, 1.04–2.17), more concomitant medications (1.47, 1.13–1.92), commercial insurance (1.41, 1.07–1.85), and heart failure (1.44, 1.07–1.92). Antiplatelet drugs (0.18, 0.14–0.23), prior falls (0.41, 0.27–0.63), and prior bleeding (0.50, 0.35–0.72) were inversely associated with OAC prescription.

Conclusions

In GLORIA‐AF, 20% of the population comprising males with CHA₂DS₂‐VASc ≥1 and females with CHA₂DS₂‐VASc ≥2 did not receive OAC therapy. Patient characteristics associated with a lower likelihood of OAC prescription were use of antiplatelet drugs, paroxysmal pattern of AF, history of falls, and prior bleeding.