Time to benefit and harm of direct oral anticoagulants in device-detected atrial fibrillation: A pooled analysis of the NOAH-AFNET 6 and ARTESiA trials

BACKGROUND

Direct oral anticoagulants (DOACs) reduce stroke risk in patients with device-detected atrial fibrillation (DD-AFib) but increase major bleeding risk. The time to benefit (TTB) and time to harm (TTH) are not well quantified.

OBJECTIVE

The purpose of this study was to determine TTB and TTH in DOAC-treated patients with DD-AFib.

METHODS

Studies were identified from PubMed searching until November 2023. The primary efficacy outcome was the time to the first stroke event, and the primary safety outcome was the time to the first major bleeding event. Pooled hazard ratio (HR) and its confidence interval (CI) were calculated through reconstructed patient-level data and study-level data. Weibull model and Markov chain Monte Carlo simulation were applied to determine time to specific absolute risk change thresholds.

RESULTS

Two trials involving DOACs-NOAH-AFNET 6 (Non-vitamin K antagonist Oral anticoagulants in patients with Atrial High rate episodes) and ARTESiA (Apixaban for the Reduction of Thrombo-Embolism in Patients With Device-Detected Sub-Clinical Atrial Fibrillation)-were identified, which randomized 6548 adults with a mean age of >75 years and a median atrial high-rate episode duration ranging from 1.5 to 2.8 hours. DOACs decreased the risk of stroke (HR 0.67; 95% CI 0.50-0.90) but increased the risk of major bleeding (HR 1.57; 95% CI 1.21-2.04). A TTB of 2.67 years was needed to prevent 1 stroke per 100 DOAC-treated patients, while a TTH of 1.67 years was needed to observe 1 major bleeding.

CONCLUSION

In elderly patients with low durations of DD-AFib, DOACs result in a delayed and restricted stroke-preventive benefit while posing an early-onset bleeding risk. Our findings offer new insights into the risk-benefit profile and provide clinicians an additional dimension to facilitate shared decision-making discussions with patients.

Atrial Fibrillation Burden: Impact on Stroke Risk and Beyond

Atrial fibrillation (AF) is an important independent risk factor for stroke. Current guidelines handle AF as a binary entity with risk driven by the presence of clinical risk factors, which guides the decision to treat with an oral anticoagulant. Recent studies in the literature suggest a dose-response relationship between AF burden and stroke risk, in both clinical AF and subclinical atrial fibrillation (SCAF), which differs from current guidance to disregard burden and utilize clinical risk scores alone. Within clinical classification and at the same risk levels in various scores, the risk of stroke increases with AF burden. This opens the possibility of incorporating burden into risk profiles, which has already shown promise. Long-term rhythm monitoring is needed to elucidate SCAF in patients with stroke. Recent data from randomized trials are controversial regarding whether there is an independent risk from AF episodes with a duration of less than 24 h, including the duration of SCAF greater than six minutes but less than 24 h.

Anticoagulation with edoxaban in patients with long atrial high-rate episodes ≥24 h

BACKGROUND AND AIMS

Patients with long atrial high-rate episodes (AHREs) ≥24 h and stroke risk factors are often treated with anticoagulation for stroke prevention. Anticoagulation has never been compared with no anticoagulation in these patients.

METHODS

This secondary pre-specified analysis of the Non-vitamin K antagonist Oral anticoagulants in patients with Atrial High-rate episodes (NOAH-AFNET 6) trial examined interactions between AHRE duration at baseline and anticoagulation with edoxaban compared with placebo in patients with AHRE and stroke risk factors. The primary efficacy outcome was a composite of stroke, systemic embolism, or cardiovascular death. The safety outcome was a composite of major bleeding and death. Key secondary outcomes were components of these outcomes and electrocardiogram (ECG)-diagnosed atrial fibrillation.

RESULTS

Median follow-up of 2389 patients with core lab-verified AHRE was 1.8 years. AHRE ≥24 h were present at baseline in 259/2389 patients (11%, 78 ± 7 years old, 28% women, CHA2DS2-VASc 4). Clinical characteristics were not different from patients with shorter AHRE. The primary outcome occurred in 9/132 patients with AHRE ≥24 h (4.3%/patient-year, 2 strokes) treated with anticoagulation and in 14/127 patients treated with placebo (6.9%/patient-year, 2 strokes). Atrial high-rate episode duration did not interact with the efficacy (P-interaction = .65) or safety (P-interaction = .98) of anticoagulation. Analyses including AHRE as a continuous parameter confirmed this. Patients with AHRE ≥24 h developed more ECG-diagnosed atrial fibrillation (17.0%/patient-year) than patients with shorter AHRE (8.2%/patient-year; P < .001).

CONCLUSIONS

This hypothesis-generating analysis does not find an interaction between AHRE duration and anticoagulation therapy in patients with device-detected AHRE and stroke risk factors. Further research is needed to identify patients with long AHRE at high stroke risk.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

Atrial fibrillation detected with outpatient cardiac rhythm monitoring in patients with ischemic stroke or TIA of undetermined cause

OBJECTIVES

Guidelines advise cardiac rhythm monitoring for 3 up to 30 days for detecting atrial fibrillation (AF) in patients with ischemic stroke of undetermined cause. However, the optimal monitoring duration is unknown. We aimed to determine the AF detection rate during 7-day outpatient cardiac rhythm monitoring in this patient group.

METHODS

Participants from a large tertiary hospital in a prospective observational study (ATTEST) underwent outpatient cardiac rhythm monitoring after a negative standard diagnostic evaluation (i.e., 12-lead electrocardiogram and in-hospital telemetry). Primary outcome was the rate of newly detected AF.

RESULTS

We examined 373 patients [age: 67.8±11.6 years; women: 166(44.5%); stroke: 278(74.5%)]. Median monitoring duration was 7 days (Inter Quartile Range (IQR) 7-7), performed after median of 36 days (IQR 27-47). AF was newly detected in 17(4.6%) patients, 5.4% of patients with ischemic stroke and 2.1% of patients with TIA. 53% of AF was detected on day-1, after day-3 73% of new AF was found. First AF episodes were detected up to day-7. Diabetes and increasing age were independent predictors of new AF.

CONCLUSION

After ischemic stroke or TIA of undetermined cause, 7-day outpatient cardiac rhythm monitoring detected new AF in 4.6%. Patients with AF had significantly more cardiovascular risk factors. Although about 50% of first AF episodes occurred during the first day of monitoring, new AF was detected up to day-7, implying that the recommended minimum of 3 days cardiac rhythm monitoring after ischemic stroke of undetermined cause is insufficient. Subsequent long-term rhythm monitoring should be considered in selected patients.

The influence of atrial high-rate episodes on stroke and cardiovascular death: an update

Atrial high-rate episodes (AHRE) are atrial tachyarrhythmias detected by continuous rhythm monitoring by pacemakers, defibrillators, or implantable cardiac monitors. Atrial high-rate episodes occur in 10-30% of elderly patients without atrial fibrillation. However, it remains unclear whether the presence of these arrhythmias has therapeutic consequences. The presence of AHRE increases the risk of stroke compared with patients without AHRE. Oral anticoagulation would have the potential to reduce the risk of stroke in patients with AHRE but is also associated with a rate of major bleeding of ∼2%/year. The stroke rate in patients with AHRE appears to be lower than the stroke rate in patients with atrial fibrillation. Wearables like smart-watches will increase the absolute number of patients in whom atrial arrhythmias are detected. It remains unclear whether anticoagulation is effective and, equally important, safe in patients with AHRE. Two randomized clinical trials, NOAH-AFNET6 and ARTESiA, are expected to report soon. They will provide much-needed information on the efficacy and safety of oral anticoagulation in patients with AHRE.

Atrial high-rate episodes intensify R2CHA2DS2-VASc score for prognostic stratification in pacemaker patients

Patients with device detected atrial high-rate episodes (AHRE) have an increased risk of MACE. The R₂CHA₂DS₂-VASc, CHADS₂, R₂CHADS₂ and CHA₂DS₂-VASc score have been investigated for predicting major adverse cardiovascular events (MACE) in different groups of patients. We aimed to evaluate the R₂CHA₂DS₂-VASc score in combination with AHRE ≥ 6 min for predicting MACE in patients with dual-chamber PPM but no prior atrial fibrillation (AF). We retrospectively enrolled 376 consecutive patients undergoing dual-chamber PPM implantation and no prior AF. The primary endpoint was subsequent MACE. For all patients in the cohort, CHADS₂, R₂CHADS₂, CHA₂DS₂-VASc, R₂CHA₂DS₂-VASc scores and AHRE ≥ or < 6 min were determined. AHRE was recorded as a heart rate > 175 bpm (Medtronic) or > 200 bpm (Biotronik) lasting ≥ 30 s. Multivariate Cox regression analysis with time-dependent covariates was used to determine the independent predictors of MACE. ROC-AUC analysis was performed for CHADS₂, R₂CHADS₂, CHA₂DS₂-VASc, and R₂CHA₂DS₂-VASc scores and then adding AHRE ≥ 6 min to the four scores. The median age was 77 years, and 107 patients (28.5%) developed AHRE ≥ 6 min. After a median follow-up of 32 months, 46 (12.2%) MACE occurred. Multivariate Cox regression analysis showed that R₂CHA₂DS₂-VASc score (HR, 1.485; 95% CI, 1.212-1.818; p < 0.001) and AHRE ≥ 6 min (HR, 2.125; 95% CI, 1.162-3.887; p = 0.014) were independent predictors for MACE. The optimal R₂CHA₂DS₂-VASc score cutoff value was 4.5 (set at ≥ 5), with the highest Youden index (AUC, 0.770; 95% CI, 0.709-0.831; p < 0.001). ROC-AUC analysis of the four risk scores separately combined with AHRE ≥ 6 min all showed better discriminatory power than the four scores alone (All Z-statistic p < 0.05). In patients with PPM who develop AHRE ≥ 6 min, it is crucial to perform risk assessment with either four scores to further stratify risk for MACE.

Automatic screening of patients with atrial fibrillation from 24-h Holter recording using deep learning

Aims

As the demand for atrial fibrillation (AF) screening increases, clinicians spend a significant amount of time identifying AF signals from massive amounts of data obtained during long-term dynamic electrocardiogram (ECG) monitoring. The identification of AF signals is subjective and depends on the experience of clinicians. However, experienced cardiologists are scarce. This study aimed to apply a deep learning-based algorithm to fully automate primary screening of patients with AF using 24-h Holter monitoring.

Methods and results

A deep learning model was developed to automatically detect AF episodes using RR intervals and was trained and evaluated on 23 621 (2297 AF and 21 324 non-AF) 24-h Holter recordings from 23 452 patients. Based on the AF episode detection results, patients with AF were automatically identified using the criterion of at least one AF episode lasting 6 min or longer. Performance was assessed on an independent real-world hospital-scenario test set (19 227 recordings) and a community-scenario test set (1299 recordings). For the two test sets, the model obtained high performance for the identification of patients with AF (sensitivity: 0.995 and 1.000; specificity: 0.985 and 0.997, respectively). Moreover, it obtained good and consistent performance (sensitivity: 1.000; specificity: 0.972) for an external public data set.

Conclusion

Using the criterion of at least one AF episode of 6 min or longer, the deep learning model can fully automatically screen patients for AF with high accuracy from long-term Holter monitoring data. This method may serve as a powerful and cost-effective tool for primary screening for AF.

Atrial high-rate episode burden and stroke risks for patients with device-detected subclinical atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Atrial high-rate episode (AHRE) and stroke are related; however, the magnitude of the correlations between different AHRE burdens and stroke remains unknown. We analysed studies that evaluated this relationship.

METHODS

We searched for observational controlled studies that reported the associations of different AHRE burdens with stroke in populations with cardiac implantable electronic devices (CIEDs). The primary endpoint was stroke or thrombosis during follow-up. We performed subgroup analyses according to the classification criteria and research design of the included studies.

RESULTS

Of the 5985 studies identified, 9 met the eligibility criteria and included 42,958 patients. Patients with low and high AHRE burdens had a 1.2-fold risk of stroke (no heterogeneity) and a 2.52-fold risk of stroke (moderate heterogeneity), respectively. After excluding studies analysing the atrial fibrillation history, no significant difference in progressive stroke risk was observed for patients with a low AHRE burden (without significant heterogeneity). An increased likelihood of stroke was observed for patients with a high AHRE burden (decreased heterogeneity). Four of the nine studies classified high and low AHRE burdens using the longest AHRE time. Five studies classified high and low AHRE burdens based on the median of the total AHRE time as the cutoff value. Low and high AHRE burdens were more closely related to stroke when classified by the total AHRE duration than when classified by the single longest AHRE duration.

CONCLUSIONS

For populations with CIEDs without an atrial fibrillation history, a high AHRE burden was significantly associated with stroke.

Consumer-Led Screening for Atrial Fibrillation: Frontier Review of the AF-SCREEN International Collaboration

The technological evolution and widespread availability of wearables and handheld ECG devices capable of screening for atrial fibrillation (AF), and their promotion directly to consumers, has focused attention of health care professionals and patient organizations on consumer-led AF screening. In this Frontiers review, members of the AF-SCREEN International Collaboration provide a critical appraisal of this rapidly evolving field to increase awareness of the complexities and uncertainties surrounding consumer-led AF screening. Although there are numerous commercially available devices directly marketed to consumers for AF monitoring and identification of unrecognized AF, health care professional-led randomized controlled studies using multiple ECG recordings or continuous ECG monitoring to detect AF have failed to demonstrate a significant reduction in stroke. Although it remains uncertain if consumer-led AF screening reduces stroke, it could increase early diagnosis of AF and facilitate an integrated approach, including appropriate anticoagulation, rate or rhythm management, and risk factor modification to reduce complications. Companies marketing AF screening devices should report the accuracy and performance of their products in high- and low-risk populations and avoid claims about clinical outcomes unless improvement is demonstrated in randomized clinical trials. Generally, the diagnostic yield of AF screening increases with the number, duration, and temporal dispersion of screening sessions, but the prognostic importance may be less than for AF detected by single-time point screening, which is largely permanent, persistent, or high-burden paroxysmal AF. Consumer-initiated ECG recordings suggesting possible AF always require confirmation by a health care professional experienced in ECG reading, whereas suspicion of AF on the basis of photoplethysmography must be confirmed with an ECG. Consumer-led AF screening is unlikely to be cost-effective for stroke prevention in the predominantly young, early adopters of this technology. Studies in older people at higher stroke risk are required to demonstrate both effectiveness and cost-effectiveness. The direct interaction between companies and consumers creates new regulatory gaps in relation to data privacy and the registration of consumer apps and devices. Although several barriers for optimal use of consumer-led screening exist, results of large, ongoing trials, powered to detect clinical outcomes, are required before health care professionals should support widespread adoption of consumer-led AF screening.

Protocol for Home-Based Solution for Remote Atrial Fibrillation Screening to Prevent Recurrence Stroke (HUA-TUO AF Trial): a randomised controlled trial

INTRODUCTION

Current international guidelines recommend ECG monitoring after an ischaemic stroke to detect atrial fibrillation (AF) in order to prevent stroke recurrence. However, optimal strategies to detect AF and the downstream management to prevent stroke recurrence remain to be established. The objective of the study was to explore the use of long-term home-based ECG monitoring for AF detection and stroke prevention in patients with a history of stroke.

METHODS AND ANALYSIS

This prospective, randomised, open-label trial with blinded endpoint adjudication aimed to evaluate the efficacy of long-term home-based ECG monitoring for AF detection and stroke prevention in a 24-month period. Patients aged >18 years with a history of ischaemic stroke will be stratified according to the time from the index ischaemic stroke: <1, 1-3 and >3 years and then randomised in 1:1 to (1) home-based AF screening and (2) control. The home-based AF screening system comprises (1) a handheld single-lead ECG recorder (Comfit Healthcare Devices, Hong Kong SAR, China) and (2) a patient-facing smartphone application specially designed for the study. Patients randomised to the home-based AF group will record a 30 s single-lead ECG using a specially designed handheld ECG device every morning or when symptomatic. All remotely obtained data will be automatically transmitted in real-time through the study smartphone application to a secured cloud hosting and analysed using an artificial intelligence-based diagnostic system. When a diagnosis of AF is made with the system, the patients will be called back for a formal cardiology consultation within 1 week. The primary endpoint is the time to first detection of AF at 24 months of follow-up. Secondary endpoints include recurrent stroke or transient ischaemic attack, initiation of long-term anticoagulation therapy, hospitalisation for heart failure, cardiovascular death and all-cause death.

ETHICS AND DISSEMINATION

The study protocol has been approved by the institutional review board of The University of Hong Kong, and Hong Kong West Cluster, Hospital Authority, Hong Kong SAR, China. Results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04523649.

Incident Stroke and Its Influencing Factors in Patients With Type 2 Diabetes Mellitus and/or Hypertension: A Prospective Cohort Study

Objective

To understand the incidence of stroke in patients with type 2 diabetes mellitus (T2DM) and/or hypertension (HTN), and provide a basis for the prevention of stroke in these patients.

Methods

A prospective cohort study was performed for adults with T2DM and/or HTN. The follow-up period was 1 year. The incidence and recurrence rate of stroke was calculated and a multivariate Cox proportional hazard was used to analyze influencing factors of stroke occurrence and recurrence in the follow-up of patients with T2DM and/or HTN.

Results

Of the 1,650 patients with T2DM and/or HTN, 1,213 patients had no history of stroke. After 1 year of follow-up, 147 new stroke cases occurred, and the incidence rate of stroke was 12.1%. Among the patients who had stroke history (413), there were 116 cases of stroke with a recurrence rate of 26.5%. Seven risk factors were independently associated with stroke occurrence among patients without stroke history, included smoking, abnormal total cholesterol abnormal low-density lipoprotein patients with comorbid T2DM with HTN, physical inactivity, carotid artery stenosis (CAS), and higher scores of National Institutes of Health Stroke Scale (NIHSS). Higher scores of NHISS and CAS were independent risk factors for the recurrence of stroke among patients with stroke history.

Conclusions

Patients with T2DM and/or HTN have a higher rate of new stroke and recurrence after 1-year follow-up. Actively identifying the controllable risk factors, such as smoking and physical inactivity, will help reduce the risk of stroke and recurrence in patients with T2DM and HTN.

Estimated incidence of previously undetected atrial fibrillation on a 14-day continuous electrocardiographic monitor and associated risk of stroke

Aims

There is uncertainty about whether and how to perform screening for atrial fibrillation (AF). To estimate the incidence of previously undetected AF that would be captured using a continuous 14-day ECG monitor and the associated risk of stroke.

Methods and results

We analysed data from a cohort of patients &gt;65 years old with hypertension and a pacemaker, but without known AF. For each participant, we simulated 1000 ECG monitors by randomly selecting 14-day windows in the 6 months following enrolment and calculated the average AF burden (total time in AF). We used Cox proportional hazards models adjusted for CHA2DS2-VASc score to estimate the risk of subsequent ischaemic stroke or systemic embolism (SSE) associated with burdens of AF &gt; and &lt;6 min. Among 2470 participants, the median CHA2DS2-VASc score was 4.0, and 44 patients experienced SSE after 6 months following enrolment. The proportion of participants with an AF burden &gt;6 min was 3.10% (95% CI 2.53–3.72). This was consistent across strata of age and CHA2DS2-VASc scores. Over a mean follow-up of 2.4 years, the rate of SSE among patients with &lt;6 min of AF was 0.70%/year, compared to 2.18%/year (adjusted HR 3.02; 95% CI 1.39–6.56) in those with &gt;6 min of AF.

Conclusions

Approximately 3% of individuals aged &gt;65 years with hypertension may have more than 6 min of AF detected by a 14-day ECG monitor. This is associated with a stroke risk of over 2% per year. Whether oral anticoagulation will reduce stroke in these patients is unknown.

HATCH Score and Left Atrial Size Predict Atrial High-Rate Episodes in Patients With Cardiac Implantable Electronic Devices

Background: Patients with sustained atrial high-rate episodes (AHRE) have a high risk of major adverse cardio/cerebrovascular events (MACCE). However, the prediction model and factors for the occurrence of AHRE are unknown. We aimed to identify independent factors and various risk models for predicting MACCE and AHRE.

Methods: We retrospectively enrolled 314 consecutive patients who had cardiac implantable electronic devices (CIEDs). The primary endpoint was MACCE after AHRE ≥3, 6 min, and 6 h. Atrial high-rate episodes was defined as >175 bpm (Medtronic^®) lasting ≥30 s. Multivariate Cox and logistic regression analysis with time-dependent covariates were used to determine variables associated with independent risk of MACCE and occurrence of AHRE ≥3 min, respectively.

Results: One hundred twenty-five patients (39.8%) developed AHRE ≥3 min, 103 (32.8%) ≥6 min, and 55 (17.5%) ≥6 h. During follow-up (median 32 months), 77 MACCE occurred (incidence 9.20/100 patient years, 95% CI 5.66–18.39). The optimal AHRE cutoff value was 3 min for MACCE, with highest Youden index 1.350 (AUC, 0.716; 95% CI, 0.638–0.793; p < 0.001). Atrial high-rate episodes ≥3 min−6 h were independently associated with MACCE. HATCH score and left atrial diameter were independently associated with AHRE ≥3 min. The optimal cutoff for HATCH score was 3 and for left atrial diameter was 4 cm for AHRE ≥3 min.

Conclusion: Patients with CIEDs who develop AHRE ≥3 min have an independently increased risk of MACCE. Comprehensive assessment using HATCH score and echocardiography of patients with CIEDs is warranted.

Device-detected atrial high rate episodes and the risk of stroke/thrombo-embolism and atrial fibrillation incidence: a systematic review and meta-analysis

BACKGROUND

Atrial High Rate Episodes (AHRE) are asymptomatic atrial tachy-arrhythmias detected through continuous monitoring with a cardiac implantable electronic device. The risks of stroke/Thromboembolic (TE) events and incident clinical Atrial Fibrillation (AF) associated with AHRE varies markedly.

OBJECTIVES

To assess the relationship between AHRE and TE events, and between AHRE and incident clinical AF.

METHODS

This systematic review and meta-analysis was conducted following the PRISMA recommendations. PubMed, Scopus, and Google Scholar were searched from inception to 18/02/2021 for studies reporting TE events and incident clinical AF in patients with AHRE, as compared with patients without.

RESULTS

Ten out of 8081 records fulfilled the inclusion criteria, for a total of 37 266 patients. Seven out of ten studies excluded patients with prior history of clinical AF (4961 patients), embracing the most recent definition of AHRE. The risk ratio (RR) for TE events in AHRE patients was 2.13 (95% CI: 1.53-2.95, I²: 0%). The incidence of clinical AF was reported in four studies excluding patients with a history of clinical AF (3574 patients). The RR for incident clinical AF was 3.34 (95%CI: 1.89-5.90, I²: 73%).

CONCLUSIONS

AHRE are significantly associated with systemic thromboembolism and incident clinical AF. Further studies are needed to improve patients' risk stratification and management.

Atrial high-rate episodes predict major adverse cardio/cerebrovascular events in patients with cardiac implantable electrical devices

Patients with atrial high-rate episodes (AHRE) have a high risk of neurologic events, although the causal role and optimal cutoff threshold of AHRE for major adverse cardio/cerebrovascular events (MACCE) are unknown. This study aimed to identify independent factors for AHRE and subsequent atrial fibrillation (AF) after documented AHRE. We enrolled 470 consecutive patients undergoing cardiac implantable electrical device (CIED) implantations. The primary endpoint was subsequent MACCE after AHRE ≥ 6 min, 6 h, and 24 h. AHRE was defined as > 175 beats per minute (bpm) (Medtronic®) or > 200 bpm (Biotronik®) lasting ≥ 30 s. Multivariate Cox regression analysis with time-dependent covariates was used to determine variables associated with independent risk of MACCE. The patients’ median age was 76 year, and 126 patients (26.8%) developed AHRE ≥ 6 min, 63 (13.4%) ≥ 6 h, and 39 (8.3%) ≥ 24 h. During follow-up (median: 29 months), 142 MACCE occurred in 123 patients. Optimal AHRE cutoff value was 6 min, with highest Youden index for MACCE. AHRE ≥ 6 min ~ 24 h was independently associated with MACCE and predicted subsequent AF. Male gender, lower body mass index, or BMI, and left atrial diameter were independently associated with AHRE ≥ 6 min ~ 24 h. Patients with CIEDs who develop AHRE ≥ 6 min have an independently increased risk of MACCE. Comprehensive assessment of patients with CIEDs is warranted.

Atrial fibrillation burden: an update-the need for a CHA2DS2-VASc-AFBurden score

Atrial fibrillation (AF) is an established independent risk factor for stroke. Current guidelines regard AF as binary; either present or absent, with the decision for anti-coagulation driven by clinical variables alone. However, there are increasing data to support a biological gradient of AF burden and stroke risk, both in clinical and non-clinical AF phenotypes. As such, this raises the concept of combining AF burden assessment with a clinical risk score to refine and individualize the assessment of stroke risk in AF-the CHA2DS2VASc-AFBurden score. We review the published data supporting a biological gradient to try and construct a putative schema of risk attributable to AF burden.

Lower risk of stroke after alcohol abstinence in patients with incident atrial fibrillation: a nationwide population-based cohort study

Aims 

The aim of this study was to evaluate the association between alcohol consumption status (and its changes) after newly diagnosed atrial fibrillation (AF) and the risk of ischaemic stroke.

Methods and results 

Using the Korean nationwide claims and health examination database, we included subjects who were newly diagnosed with AF between 2010 and 2016. Patients were categorized into three groups according to the status of alcohol consumption before and after AF diagnosis: non-drinkers; abstainers from alcohol after AF diagnosis; and current drinkers. The primary outcome was incident ischaemic stroke during follow-up. Non-drinkers, abstainers, and current drinkers were compared using incidence rate differences after the inverse probability of treatment weighting (IPTW). Among a total of 97 869 newly diagnosed AF patients, 51% were non-drinkers, 13% were abstainers, and 36% were current drinkers. During 310 926 person-years of follow-up, 3120 patients were diagnosed with incident ischaemic stroke (10.0 per 1000 person-years). At 5-year follow-up, abstainers and non-drinkers were associated with a lower risk for stroke than current drinkers (incidence rate differences after IPTW, −2.03 [−3.25, −0.82] for abstainers and −2.98 [−3.81, −2.15] for non-drinkers, per 1000 person-years, respectively; and incidence rate ratios after IPTW, 0.75 [0.70, 0.81] for non-drinkers and 0.83 [0.74, 0.93] for abstainers, respectively).

Conclusion 

Current alcohol consumption was associated with an increased risk of ischaemic stroke in patients with newly diagnosed AF, and alcohol abstinence after AF diagnosis could reduce the risk of ischaemic stroke. Lifestyle intervention, including attention to alcohol consumption, should be encouraged as part of a comprehensive approach to AF management to improve clinical outcomes.

The optimal cutoff of atrial high-rate episodes for neurological events in patients with dual chamber permanent pacemakers

BACKGROUND

Patients with atrial high-rate episode (AHRE) are at higher risk of neurological events. This study aimed to identify the optimal cutoff threshold for AHRE duration in patients with dual chamber permanent pacemakers (PPM) without prior atrial fibrillation.

METHODS

We included 355 consecutive patients receiving dual chamber pacemaker implantation. Primary outcome was composite endpoint of subsequent neurological events after various AHRE durations. AHRE was defined as >175 bpm (MEDTRONIC) or > 200 bpm (BIOTRONIK) for longer than 30 s. Cox regression analysis with time-dependent covariates was conducted.

RESULTS

The mean age of included patients was 75.6 ± 11.3 years. Among 355 included patients, some had multiple AHREs; 125 patients (35.2%) developed AHRE ≥2 min, 107 (30.1%) had ≥5 min, 55 (15.5%) had ≥6 h, and 37 (10.4%) had ≥24 h. The mean follow-up was 42.1 ± 31.2 months. During follow-up, 19 neurological events occurred. After adjustment for CHA2 DS2 -VASc score and device type, multivariate Cox regression analysis indicated AHRE ≥2 min (HR 13.605, 95% CI 3.010-61.498), and AHRE ≥5 min (HR 5.819, 95% CI 2.056-16.470) were significantly associated with neurological events. Hence, the optimal AHRE cutoff value was 2 min with the highest Youden index (sensitivity, 89.5%; specificity, 67.8%; AUC, 0.823, 95% CI, 0.763-0.884; p < 0.001).

CONCLUSIONS

Patients with dual chamber PPM who develop AHRE have increased risk of neurological events. Comprehensive assessment of the risks and benefits of prescribing anticoagulants should be considered in PPM patients with AHRE ≥2 min.

Screening for Atrial Fibrillation in the Older Population: A Randomized Clinical Trial

Importance

Atrial fibrillation (AF) is a major cause of preventable strokes. Screening asymptomatic individuals for AF may increase anticoagulant use for stroke prevention.

Objective

To evaluate 2 home-based AF screening interventions.

Design, Setting, and Participants

This multicenter randomized clinical trial recruited individuals from primary care practices aged 75 years or older with hypertension and without known AF. From April 5, 2015, to March 26, 2019, 856 participants were enrolled from 48 practices.

Interventions

The control group received standard care (routine clinical follow-up plus a pulse check and heart auscultation at baseline and 6 months). The screening group received a 2-week continuous electrocardiographic (cECG) patch monitor to wear at baseline and at 3 months, in addition to standard care. The screening group also received automated home blood pressure (BP) machines with oscillometric AF screening capability to use twice-daily during the cECG monitoring periods.

Main Outcomes and Measures

With intention-to-screen analysis, the primary outcome was AF detected by cECG monitoring or clinically within 6 months. Secondary outcomes included anticoagulant use, device adherence, and AF detection by BP monitors.

Results

Of the 856 participants, 487 were women (56.9%); mean (SD) age was 80.0 (4.0) years. Median cECG wear time was 27.4 of 28 days (interquartile range [IQR], 18.4-28.0 days). In the primary analysis, AF was detected in 23 of 434 participants (5.3%) in the screening group vs 2 of 422 (0.5%) in the control group (relative risk, 11.2; 95% CI, 2.7-47.1; P = .001; absolute difference, 4.8%; 95% CI, 2.6%-7.0%; P < .001; number needed to screen, 21). Of those with cECG-detected AF, median total time spent in AF was 6.3 hours (IQR, 4.2-14.0 hours; range 1.3 hours-28 days), and median duration of the longest AF episode was 5.7 hours (IQR, 2.9-12.9 hours). Anticoagulation was initiated in 15 of 20 patients (75.0%) with cECG-detected AF. By 6 months, anticoagulant therapy had been prescribed for 18 of 434 participants (4.1%) in the screening group vs 4 of 422 (0.9%) in the control group (relative risk, 4.4; 95% CI, 1.5-12.8; P = .007; absolute difference, 3.2%; 95% CI, 1.1%-5.3%; P = .003). Twice-daily AF screening using the home BP monitor had a sensitivity of 35.0% (95% CI, 15.4%-59.2%), specificity of 81.0% (95% CI, 76.7%-84.8%), positive predictive value of 8.9% (95% CI, 4.9%-15.5%), and negative predictive value of 95.9% (95% CI, 94.5%-97.0%). Adverse skin reactions requiring premature discontinuation of cECG monitoring occurred in 5 of 434 participants (1.2%).

Conclusions and Relevance

In this randomized clinical trial, among older community-dwelling individuals with hypertension, AF screening with a wearable cECG monitor was well tolerated, increased AF detection 10-fold, and prompted initiation of anticoagulant therapy in most cases. Compared with continuous ECG, intermittent oscillometric screening with a BP monitor was an inferior strategy for detecting paroxysmal AF. Large trials with hard clinical outcomes are now needed to evaluate the potential benefits and harms of AF screening.

Trial Registration

ClinicalTrials.gov Identifier: NCT02392754.

High-Sensitivity C-Reactive Protein is a Predictor of Subsequent Atrial High-Rate Episodes in Patients with Pacemakers and Preserved Ejection Fraction

Atrial fibrillation (AF) is associated with morbidity and mortality. Modern pacemakers can detect atrial high-rate episodes (AHREs) as a surrogate for AF. It remains controversial whether inflammation is a cause or a consequence of AF. This study investigated whether the inflammatory biomarker high-sensitivity C-reactive protein (hs-CRP) can predict subsequent AHREs. This study gathered prospective data from patients with pacemakers and a left ventricle EF ≥ 50% between 2015 and 2019. The hs-CRP and other cardiac biomarkers at baseline and device-detected AHREs, defined as atrial rate ≥ 180 bpm and duration ≥ 6 min, were determined. Cox regression analysis was used to estimate the independent predictors for AHREs. A total of 171 consecutive patients were included. During the median follow-up of 614 days, 66 patients (39%) developed subsequent AHREs. In the univariate Cox regression analysis, sick sinus syndrome (p = 0.005), prior AF (p < 0.001), mitral A velocity (p = 0.008), and hs-CRP (p = 0.013) showed significant association with the increased risk of AHREs. In the multivariate Cox regression model, hs-CRP (HR = 1.121, 95% confidence interval = 1.015-1.238, p = 0.024) retained its significance. Our results suggest that elevated hs-CRP could predict subsequent AHREs and that inflammation could play a role in AF pathogenesis in patients with preserved EF.

Left ventricular stiffness assessed by diastolic Wall strain predicts asymptomatic atrial high-rate episodes in patients with pacemaker implantation

BACKGROUND

Cardiac implantable electronic device-detected atrial high-rate episodes (AHREs) have been reported to be associated with thromboembolic risks. The present study aimed to investigate the association of echocardiographic and clinical parameters with the occurrence of AHREs in patients with a dual-chamber pacemaker (PMI).

METHODS

One hundred forty-seven patients (76 males, 75.2 ± 8.9 years) who did not show atrial tachyarrhythmia before the implantation of the PMI were studied. Diastolic wall strain (DWS) and other measurements were assessed during sinus rhythm using transthoracic echocardiography before the PMI. DWS was calculated from the M-mode echocardiographic measurement of the left ventricular (LV) posterior wall thickness at end-systole (PWs) and end-diastole (PWd), and DWS was defined as (PWs-PWd) / PWs.

RESULTS

AHREs (defined as AHREs duration >6 min and atrial rate >180 bpm) were detected in 50 / 147 patients during follow up (38.3 ± 13.8 months). Patients in the AHREs group had reduced DWS (0.29 ± 0.07 vs. 0.39 ± 0.06, p < 0.0001), larger left atrial volume index, thicker LV posterior diameter, higher rate of patients taking β-blocker / diuretics, and higher prevalence of sinus node dysfunction. On multivariable analysis, only DWS was independently associated with AHREs. Patients with reduced DWS (<0.33) had a higher risk of incidences of AHREs.

CONCLUSION

LV stiffness assessed by DWS was associated with AHREs in patients with a PMI.

Duration of atrial high-rate episodes and CHA2DS2-VASc score to predict cardiovascular and cerebrovascular events in patients with dual chamber permanent pacemakers

BACKGROUND

Patients with atrial high-rate episodes (AHRE) have a high risk of cardiovascular and cerebrovascular events (CCE); however, the optimal cut-off threshold for AHRE duration and the prediction power of AHRE with CHA₂DS₂-VASc score is unknown.

METHODS

We enrolled 355 consecutive patients undergoing dual chamber pacemaker implantations. The primary endpoint was subsequent CCE after AHRE ≥ 30 seconds, 1 minute, 2 minutes, 5 minutes, 6 hours, and 24 hours. AHRE was defined as >175 bpm (Medtronic, Dublin, Ireland) or >200 bpm (Biotronik, Berlin, Germany) lasting ≥30 seconds. Multivariate Cox regression analysis with time-dependent covariates was used to determine the variables associated with higher risks of CCE.

RESULTS

The average age of the patients was 75.6 ± 11.3 years, and 162 patients (45.6%) developed AHRE ≥ 30 seconds, 145 (40.8%) ≥1 minute, 125 (35.2%) ≥2 minutes, 107 (30.1%) ≥5 minutes, 55 (15.5%) ≥6 hours, and 37 (10.4%) ≥24 hours. During follow-up (mean 42.1 ± 31.2 months), 145 CCE occurred in 107 patients (incidence rate 11.64/100 patient-years, 95% CI 9.99-13.70). The optimal AHRE cut-off value was 1 minute (sensitivity, 57.9%; specificity, 66.0%; area-under-the-curve, 0.631; 95% CI, 0.563-0.698; p < 0.001). Multivariate Cox regression analysis demonstrated that all categories of AHRE duration were independently associated with CCE. The occurrence of CCE increased with AHRE ≥30 seconds and CHA₂DS₂-VASc score ≥2 (males) or ≥3 (females).

CONCLUSION

Patients with dual chamber pacemakers who develop AHRE ≥ 30 seconds have an increased risk of CCE. The combination of AHRE duration ≥30 seconds and CHA₂DS₂-VASc score ≥2 (males) or ≥3 (females) is a useful risk-stratification predictor for subsequent CCE.

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.

Rhythm monitoring strategies in patients at high risk for atrial fibrillation and stroke: A comparative analysis from the REVEAL AF study

BACKGROUND

Reducing atrial fibrillation (AF)-related stroke requires timely AF diagnosis, but the optimal monitoring strategy is unknown.

OBJECTIVE

We used insertable cardiac monitor (ICM) data from the REVEAL AF study to compare AF detection rates by various short-term continuous monitoring (STM) strategies.

METHODS AND RESULTS

Patients without known AF, but with CHADS₂ scores ≥3 (or = 2 with ≥1 additional AF risk factor) received an ICM for AF detection. One-time STM strategies were assessed by computing AF incidence at 1, 2, 7, 14, and 30 days post-ICM insertion. Repeated STM strategies (quarterly 24-hour, 48-hour, 7-day, or monthly 24-hour monitoring) were modeled by randomly selecting day(s) within a 30-day window around each nominal evaluation date over a 1-year period (simulated 10,000 times). Endpoints included AF ≥6 minutes, AF ≥1 hour, and daily AF burden ≥1 and ≥ 5.5 hours. The impact of compliance on AF detection was evaluated using daily compliance rates of 85%, 75%, 65% and 55% during follow-up months 1-3, 4-6, 7-9, and 9-12, respectively. Based on data from 385 patients (71.5 ± 9.9 years; CHADS₂ score 3.0 ± 1.0) the incidence of AF ≥6 minutes via ICM at 12 months was 27.1% (95% CI, 22.5-31.5%). This exceeded the range of estimated rates from all modeled one-time and repeated STM strategies (0.8% for 24-hour Holter monitoring to 10.6% for quarterly 7-day monitoring). Findings were similar for all AF endpoints. Modeled non-compliance reduced AF detection by 4.5% to 22.9%.

CONCLUSIONS

Most AF episodes detected via ICMs would go undetected via conventional STM strategies, thus preventing optimal prophylaxis for adverse consequences.

Changes in Management Following Detection of Previously Unknown Atrial Fibrillation by an Insertable Cardiac Monitor (from the REVEAL AF Study)

The REVEAL AF study demonstrated a high incidence of previously undetected atrial fibrillation (AF) using insertable cardiac monitors (ICMs) in patients with risk factors for AF and stroke. This analysis evaluated whether ICM monitoring led to changes in clinical management after AF detection. Patients with CHADS₂ scores ≥3 (or =2 with ≥1 additional AF risk factor) but no history of AF received an ICM and were followed 18 to 30 months. Physicians recorded changes in clinical management in response to AF detection at scheduled (every 6 months) and unscheduled follow-up visits. Changes in clinical management included oral anticoagulation, rhythm or rate control pharmacotherapy, cardioversion, ablation, and cardiac subspecialist referral. In 387 patients who met inclusion criteria and received an ICM, AF was found in 115. A change in clinical management was taken in 87 patients with AF (76%). In 80 of these 87, a change was taken at the first visit after AF detection. In total, 31 patients (27%) with AF had ≥2 visits at which changes in clinical management were taken. The most common change was initiation of oral anticoagulation (n = 73, 63% of patients with AF). Patients with a change in clinical management at the first visit after AF detection tended to have longer AF episodes and a higher maximal daily AF burden compared with AF patients for whom no change was taken (longest episode: 52 vs 28 minutes; maximal daily AF burden:112 vs 23 minutes). Changes in management more frequently occurred at visits where patients reported AF-compatible symptoms (65% vs 46% of visits, p = 0.01). In conclusion, ICM monitoring to identify AF guides both immediate and long-term patient management in a population at high risk for stroke.

Are atrial high rate episodes (AHREs) a precursor to atrial fibrillation?

Abstract

Atrial high rate episodes (AHREs), also termed, subclinical atrial tachyarrhythmias or subclinical atrial fibrillation (AF) are an important cardiovascular condition. Advancement in implantable cardiac devices such as pacemakers or internal cardiac defibrillators has enabled the continuous assessment of atrial tachyarrhythmias in patients with an atrial lead. Patients with device-detected AHREs are at an elevated risk of stroke and may have unmet anticoagulation needs. While the benefits of oral anticoagulation for stroke prevention in patients with clinical AF are well recognised, it is not known whether the same risk–benefit ratio exists for anticoagulation therapy in patients with AHREs. The occurrence and significance of AHRE are increasingly acknowledged but these events are still not often acted upon in patients presenting with stroke and TIA. Additionally, patients with AHRE show a significant risk for major adverse cardiovascular events (MACE) including acute heart failure, myocardial infarction, cardiovascular hospitalisation, ventricular tachycardia/fibrillation, which is dependent on AHRE burden. In this review, we present an overview of this relatively new entity, its associated thromboembolic risk and its management implications.

Graphic abstract

Evaluating the Effect of Comprehensive Intervention on Cerebro-Vascular Function in Population at High Risk of Stroke

BACKGROUND

Today there exists few intervention researches on cerebro-vascular function in populations at high risk of stroke in China.

METHODS

Patients more than 40 years old, with at least 1 of stroke risk factors were recruited from outpatient department in 3 hospitals. A quasi-experimental design was performed by assigning participants into 3 groups: comprehensive intervention group, health education group, and control group. Participants in the control group received no intervention but were informed of risk factors of stroke. For health education group, a health education class was performed. Except to the health education program, participants in the comprehensive intervention group received an additional health life and behavior guidance.

RESULTS

After the intervention, the Cerebro-Vascular Function Scores (CVFS) had significant differences among 3 groups (F = 5.252, P < 0.05). There was a significant increase in CVFS compared to the control group (P = 0.003, 95%CI: 1.552-8.493). Significantly changes in obesity were observed in comprehensive intervention group before and after the intervention (χ² = 9.0747, P = 0.0026). The results of logistic regression showed that comprehensive intervention group had a significant decrease in prevalence of obesity (OR = 0.482, 95% CI: 0.242-0.961) compared to the control group.

CONCLUSION

Health education on stroke in a high-risk population combined with guidance on proper health life and behavior can be effective in preventing stroke.

Silent atrial fibrillation in patients with an implantable cardioverter defibrillator and coronary artery disease (INDICO AF) trial: study rationale and design

Background

Timely detection of atrial fibrillation (AF) in implantable cardioverter defibrillator (ICD) patients is clinically important for prevention of AF-related complications and inappropriate shocks. Patients with coronary artery disease (CAD) and a dual or triple chamber ICD show a high incidence of device-detected AF. Whether CAD patients with a single chamber ICD carry a similar risk for device-detected AF remains unknown.

Study design

The INDICO AF trial is an investigator-initiated, multicentre, observational study evaluating the incidence of subclinical AF (SCAF) in CAD patients who will receive a single chamber ICD as primary prevention for sudden cardiac death (SCD). Fifty patients will receive a single chamber ICD with an integrated RR interval based AF detection algorithm. In combination with remote monitoring, rhythm data will be collected monthly. The primary endpoint is the incidence of SCAF at 1 year of follow-up; secondary endpoints include time until 10 and 20% of the patients have a first episode of SCAF. All patients in whom SCAF is detected will be invited for an outpatient visit and will receive adequate anticoagulation treatment when appropriate according to the CHA2DS2-VASc score and current guidelines.

Conclusion

The INDICO AF trial will quantify the incidence of SCAF in patients with an ICD and CAD. The study will underscore the clinical value of SCAF detection in single chamber ICD patients using remote patient monitoring and may improve patient care. This trial is registered at trialregister.nl with trial NTR6910.