Relationship between device-detected burden and duration of atrial fibrillation and risk of ischemic stroke

Impact of risk factors on atrial fibrillation types via epicardial adipose tissue computed tomography-based radiomics analysis

AIM

To analyze epicardial adipose tissue (EAT) radiomics and assess the impact of risk factors on different types of atrial fibrillation (AF).

MATERIALS AND METHODS

We included AF patients undergoing radiofrequency ablation from June 2018 to December 2020. Propensity score matching (PSM) was employed to limit the differences in risk factors between patients with different types of AF. The nnU-Net model was utilized to segment EAT. After extracting radiomic features, a generalized linear model was used to examine the epicardial adipose tissue (EAT) radiomic features associated with risk factors, and logistic regression analysis was conducted to identify the features differentiating the two AF groups. Hierarchical clustering was utilized to identify clusters among significant features.

RESULTS

After PSM, 794 patients (median age 67, 547 males) were selected, with 397 having paroxysmal and 397 persistent AF. In univariate analysis, 15.11% of the features were significantly associated with the type of AF (P<.000005). 39.29% of all features were significantly correlated with at least one risk factor, with 141 features being significantly related to both risk factors and the type of AF. Three independent clusters were successfully identified among the 141 features. The biggest cluster is dominated by hypertension and hyperlipidemia factors, exhibiting a high overlap in their effects on EAT. Following closely in influence are gender, age, and diabetes clusters, collectively covering 59 out of the 141 features.

CONCLUSION

Our study identifies distinct differences in EAT characteristics between paroxysmal and persistent AF, with persistent cases showing higher EAT gray values and a more disordered texture.

Spontaneous fluctuation in atrial fibrillation burden and duration in patients with implantable loop monitors

BACKGROUND

Most studies of device-detected atrial fibrillation (AF) have recommended indefinite anticoagulation once a patient crosses a particular threshold for AF duration or burden. However, durations and burdens are known to fluctuate over time, but little is known about the magnitude of spontaneous fluctuations and the potential impact on anticoagulation decisions.

OBJECTIVE

To quantify spontaneous fluctuations in AF duration and burden in patients with implantable loop recorders (ILRs) METHODS: We reviewed all ILR interrogations for patients with non-permanent AF at our institution from 2018 to 2023. We excluded patients treated with rhythm control. The duration of longest AF episode at each interrogation was classified as < 6, 6-24, and > 24 h, and the AF burden reported at each interrogation was classified as < 2%, 2%-11.4%, and > 11.4%.

RESULTS

Out of 156 patients, the mean age at ILR implant was 70.9 ± 12.5 years, CHA2DS2-VASc score was 4.2 ± 1.8, duration of ILR follow-up was 23.4 ± 11.2 months, and number of ILR interrogations per patient was 18.0 ± 8.9. The duration of longest AF episode at any point during follow-up was < 6 , 6-24 , and > 24 h in 110, 30, and 16 patients, respectively. Among the 30 patients with a longest AF episode of 6-24 h at some point during follow-up, out of 594 total ILR interrogations, only 75 (12%) showed a longest episode of 6-24 h. In the remaining 519 interrogations, the longest episode was < 6 h. In patients with a longest episode of > 24 h at any point during follow-up (n = 16), only 47 out of 320 total ILR interrogations (15%) showed an episode of > 24 h. When evaluating AF burden, 96, 38, and 22 patients had maximum reported AF burdens of < 2%, 2%-11.4%, and > 11.4% at any point during ILR follow-up. Among those with a maximum burden of 2%-11.4% at some point during follow-up (n = 38), out of 707 ILR interrogations, only 76 (11%) showed a burden of 2%-11.4%. In the remaining 631 interrogations, the burden was < 2%. In the 22 patients with a burden > 11.4% at some point during follow-up, only 80 out of 480 interrogations (17%) showed a burden of > 11.4%. In 65% of interrogations, the burden was < 2%.

CONCLUSION

Significant, spontaneous fluctuations in AF burden and duration are common in patients with ILRs. Even in patients with AF episodes of 6-24 h or > 24 h at some point during follow-up, the vast majority of interrogations show episodes of < 6 h. Similarly, in patients with burdens of 2%-11.4% or > 11.4% at some point during follow-up, the vast majority of interrogations show burdens of < 2%. More data are needed to determine whether crossing an AF burden or duration threshold once is sufficient to merit lifelong anticoagulation or whether spontaneous fluctuations in AF burden and duration should impact anticoagulation decisions.

Risk of Atrial Fibrillation and Adverse Outcomes in Patients With Cardiac Implantable Electronic Devices

BACKGROUND AND OBJECTIVES

Comprehensive epidemiological data are lacking on the incident atrial fibrillation (AF) in patients with cardiac implantable electronic devices (CIEDs). This study aimed to examine the incidence, risk factors, and AF-related adverse outcomes of patients with CIEDs.

METHODS

This was an observational cohort study that analyzed patients without prevalent AF who underwent CIED implantation in 2009-2018 using a Korean nationwide claims database. The subjects were divided into three groups by CIED type and indication: pacemaker (n=21,438), implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy (CRT) with heart failure (HF) (n=3,450), and ICD for secondary prevention without HF (n=2,146). The incidence of AF, AF-associated predictors, and adverse outcomes were evaluated.

RESULTS

During follow-up, the incidence of AF was 4.3, 7.3, and 5.1 per 100 person-years in the pacemaker, ICD/CRT with HF, and ICD without HF cohorts, respectively. Across the three cohorts, older age and valvular heart disease were commonly associated with incident AF. Incident AF was consistently associated with an increased risk of ischemic stroke (3.8-11.4-fold), admission for HF (2.6-10.5-fold), hospitalization for any cause (2.4-2.7-fold), all-cause death (4.1-5.0-fold), and composite outcomes (3.4-5.7-fold). Oral anticoagulation rates were suboptimal in patients with incident AF (pacemaker, 51.3%; ICD/CRT with HF, 51.7%; and ICD without HF, 33.8%, respectively).

CONCLUSIONS

A substantial proportion of patients implanted CIED developed newly diagnosed AF. Incident AF was associated with a higher risk of adverse events. The importance of awareness, early detection, and appropriate management of AF in patients with CIED should be emphasized.

Device-detected atrial fibrillation in a large remote-monitored cohort: implications for anticoagulation and need for new pathways of service delivery

BACKGROUND

Remote monitoring (RM) can facilitate early detection of subclinical and symptomatic atrial fibrillation (AF), providing an opportunity to evaluate the need for stroke prevention therapies. We aimed to characterize the burden of RM AF alerts and its impact on anticoagulation of patients with device-detected AF.

METHODS

Consecutive patients with a cardiac implantable electronic device, at least one AF episode, undergoing RM were included and assigned an estimated minimum CHA2DS2-VASc score based on age and device type. RM was provided via automated software system, providing rapid alert processing by device specialists and systematic, recurrent prompts for anticoagulation.

RESULTS

From 7651 individual, 389,188 AF episodes were identified, 3120 (40.8%) permanent pacemakers, 2260 (29.5%) implantable loop recorders (ILRs), 987 (12.9%) implantable cardioverter defibrillators, 968 (12.7%) cardiac resynchronization therapy (CRT) defibrillators, and 316 (4.1%) CRT pacemakers. ILRs transmitted 48.8% of all AF episodes. At twelve-months, 3404 (44.5%) AF < 6 min, 1367 (17.9%) 6 min-6 h, 1206 (15.8%) 6-24 h, and 1674 (21.9%) ≥ 24 h. A minimum CHA2DS2-VASc score of 2 was assigned to 1704 (63.1%) of the patients with an AF episode of ≥ 6 h, 531 (31.2%) who were not anticoagulated at 12-months, and 1031 (61.6%) patients with an AF episode duration of ≥ 24 h, 290 (28.1%) were not anticoagulated.

CONCLUSIONS

Despite being intensively managed via RM software system incorporating cues for anticoagulation, a substantial proportion of patients with increased stroke risk remained unanticoagulated after a device-detected AF episode of significant duration. These data highlight the need for improved clinical response pathways and an integrated care approach to RM.

TRIAL REGISTRATION

Australian New Zealand Clinical Trial Registry: ACTRN12620001232921.

Relationship Between Pain and Disability Among Stroke Patients

Background

Stroke is prevalent in Iran, and its complications can decline patients' quality of life and psychological state.

Objectives

This study aimed to investigate the relationship between pain following stroke (PFS) and disability in stroke patients.

Methods

The current case-control study was conducted on 184 stroke patients (92 cases and 92 controls). Data collection tools included a demographic questionnaire, the Visual Analog Scale (VAS), and the Disabilities of the Arm Shoulder and Hand (DASH) questionnaire. Based on the medical files of all patients with stroke, eligible ones were invited to participate in the study via phone calls. The collected data were then analyzed.

Results

The disability rate was higher in the case group of patients with a history of hemorrhagic stroke, smoking, stroke, and diabetes (P < 0.05). The mean ± SD age was 72.45 (11.54). Also, the level of disability in patients increased with age (P = 0.000). The mean ± SD disability score was 78.63 (6.92) in patients with PFS and 54.9 (10.87) in patients without PFS. Also, R = 0.795 and R2= 0.631 indicated the significance of disability severity in patients with PFS.

Conclusions

The prevalence of disability was higher in patients with higher PFS levels. Hence, drug interventions or rehabilitation programs can be used to reduce the disability of stroke patients.

Same-day discharge for left atrial appendage occlusion procedure: A systematic review and meta-analysis

INTRODUCTION

Most patients undergoing a left atrial appendage occlusion (LAAO) procedure are admitted for overnight observation. A same-day discharge strategy offers the opportunity to improve resource utilization without compromising patient safety. We compared the patient safety outcomes and post-discharge complications between same-day discharge versus hospital admission (HA) (>1 day) in patients undergoing LAAO procedure.

METHODS

A systematic search of MEDLINE and Embase was conducted. Outcomes of interest included peri-procedural complications, re-admissions, discharge complications including major bleeding and vascular complications, ischemic stroke, all-cause mortality, and peri-device leak >5 mm. Mantel-Haenszel risk ratios (RRs) with 95% CIs were calculated.

RESULTS

A total of seven observational studies met the inclusion criteria. There was no statistically significant difference between same-day discharge versus HA regarding readmission (RR: 0.61; 95% confidence interval [CI]: [0.29-1.31]; p = .21), ischemic stroke after discharge (RR: 1.16; 95% CI: [0.49-2.73]), peri-device leak >5 mm (RR: 1.27; 95% CI: [0.42-3.85], and all-cause mortality (RR: 0.60; 95% CI: [0.36-1.02]). The same-day discharge study group had significantly lower major bleeding or vascular complications (RR: 0.71; 95% CI: [0.54-0.94]).

CONCLUSIONS

This meta-analysis of seven observational studies showed no significant difference in patient safety outcomes and post-discharge complications between same-day discharge versus HA. These findings provide a solid basis to perform a randomized control trial to eliminate any potential confounders.

Association between atrial fibrillation burden and cognitive function in patients with atrial fibrillation

BACKGROUND

Accumulating evidence has demonstrated an association between clinical atrial fibrillation (AF) and cognitive impairment. This study aimed to further clarify the impact of AF burden on cognitive function based on detailed electrophysiological recordings and standardized assessments of cognitive function.

METHODS

This prospective cohort study, conducted at the Cardiac Electrophysiology Clinic of a tertiary center, included patients with non-valvular AF. AF burden was evaluated using 14-day patch-based electrocardiography. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA).

RESULTS

Enrolled patients (n = 253) were grouped according to the median AF burden (13.52%). Patients with higher AF burden were significantly older and had larger left atrium size, a worse ejection fraction, and a lower MoCA score than those with lower AF burden. Predictors of MoCA score included age, CHA₂DS₂-VASc score, AF burden, and Center for Epidemiologic Studies Depression Scale scores. The association between MoCA scores and AF burden remained significant after adjustment for demographic characteristics, underlying diseases, and echocardiographic parameters (standardized beta coefficient: -0.159, 95% confidence interval: -0.020 to -0.004, p = 0.004).

CONCLUSION

AF burden is associated with cognitive function in patients with AF. Further studies are required to determine whether reducing AF burden can preserve cognitive function in these patients.

REACT DX registry: Real world REACTion to atrial high rate episodes detected in implantable cardioverter-defibrillator recipients with a DX lead

BACKGROUND

Atrial fibrillation (AF) is associated with significant morbidity and is predicted by atrial high rate events. The early detection of AF is paramount to timely interventions to reduce the morbidity of AF. The DX ICD system combined with Home Monitoring® allows for continuous atrial rhythm monitoring without the need for a dedicated atrial lead.

OBJECTIVE

To establish the reaction to and timing of reactions to the detection of atrial high rate episodes (AHRE).

METHODS

A prospective cohort of DX ICD systems was followed up and the response to AHREs was collected and evaluated.

RESULTS

A total of 234 patients were enrolled; an AHRE ⩾ 6 min was detected in 13.7% of patients (n= 32) within a mean follow-up duration of 16 months. A high rate of oral anticoagulation (OAC) prescription was seen with the detection of AHREs in patients with a not-low risk CHA2DS2-VASc score. There was a delay in this prescription highlighting the potential to improve the timeliness of patient care in this group of patients.

CONCLUSIONS

The DX ICD system provides rapid and ongoing atrial rhythm monitoring such that physicians are rapidly aware of AHRE without the need for a dedicated atrial lead, but local protocols are needed to improve the response time of anti-coagulation prescription.

How is Ambulatory Electrocardiogram Predictive of Stroke in Atrial Fibrillation Patients?

Background

Atrial fibrillation (AF) is a significant stroke risk factor. Further research is needed to clarify whether higher atrial fibrillation burden (AFB) link to the elevated risk of ischemic embolism, and how AF burden could combine with CHA2DS2-VASc score to improve the anticoagulation strategy. We aim to evaluate if the AF burden characterized using 24-hours Holter ECG monitoring is associated with the risk of ischemic stroke.

Methods

This cohort study enrolled 210 Holter ECG monitoring detected atrial fibrillation patients. The burden of atrial fibrillation was defined as the percentage of time in atrial fibrillation during the monitoring period, and the AF burden and CHA2DS2-VASc score were compared between patients with and without thromboembolic outcomes. Multivariate regressions were conducted to estimate the predictors of thromboembolic outcomes.

Results

Eighteen thromboembolic events occurred within a median follow-up of 11.39 months. Patients with ischemic stroke had higher CHA2DS2-VASc scores but not higher AF burden. After adjusting for age, hypertension, diabetes, anticoagulation, antithrombotic therapy, AF burden, and AF with higher CHA2DS2-VASc score was associated with increased risk for ischemic stroke (hazard ratio (HR), 15.17). CHA2DS2-VASc score > 4.5 was a predictor of significantly higher risk of future stroke (AUC 0.92).

Conclusions

In Holter ECG monitoring detected AF, AF burden does not significantly impact the subsequent risk of stroke; whereas, CHA2DS2-VASc scoring is still a robust predictor of stroke risk. This may illustrate that once AF is detected from Holter ECG monitoring, underlying risk factors appear to be more predictive of subsequent stroke risk than atrial fibrillation burden.

Distinct atrial remodeling in patients with subclinical atrial fibrillation: Lessons from computed tomographic images

AIMS

Cardiac implanted electronic devices (CIEDs) can detect atrial high-rate episodes (AHREs) and challenge current management of subclinical atrial fibrillation (AF).

METHODS

To characterize the anatomic and functional remodeling of cardiac structures between patients with subclinical AF (SCAF) and clinical AF. The predictors for AHREs ≥6 min were also investigated.

RESULTS

We compared the atrial volume, dynamic function, and peri-atrial fat between 104 CIEDs (AHREs = 0, n = 12; SCAF, n = 66; CIEDs with AF, n = 26) and 40 paroxysmal AF patients who were planning for catheter ablation (AF for ablation) using 256-slice multidetector computed tomography for the duration of the AHREs. The maximal volume of the left atrium (LA) and LA appendage (LAA) were significantly smaller; the total emptying fraction (EF) and active EF of the LA and LAA were significantly better in the patients with SCAF than in those with clinical AF. Less peri-atrial fat (p < 0.001) and a greater LAA/ascending aorta (AA) Hounsfield unit (HU) ratio (p < 0.05) were noted in the patients with SCAF. Significantly increased volume reduced the total EF of LA and LAA and a reduced LAA/AA HU ratio (0.91 ± 0.18 vs 0.98 ± 0.03 vs 0.97 ± 0.05, p < 0.05) were demonstrated in patients with AHREs ≥6 min compared to those with AHREs <6 min and without AHRE. Multivariate analysis showed the reduced LAA/AA HU ratio is an independent predictor for the development of AHREs ≥6 min.

CONCLUSION

As compared to clinical AF, patients with SCAF show a more favorable LA remodeling process. Among the patients with device-detected AHREs, worse LA remodeling and a reduced LAA/AA HU ratio were associated with the occurrence of AHREs ≥6 min. These findings may provide an incremental value for understanding SCAF.

Arrhythmic Burden and the Risk of Cardiovascular Outcomes in Patients With Paroxysmal Atrial Fibrillation and Cardiac Implanted Electronic Devices

BACKGROUND

Whether the amount of atrial fibrillation (AF) patients experience conveys important prognostic information beyond that provided by the diagnosis of AF is uncertain. The study objective was to assess the dose-response relationship between device-detected AF burden and subsequent cardiovascular outcomes.

METHODS

Among patients with paroxysmal AF who underwent cardiac implantable electronic device implantation (2010-2016), Merlin.net remote-monitoring data were linked to Medicare claims to assess the magnitude and strength of the associations between device-based AF burden (defined as a daily percentage of time spent in AF or maximal AF episode duration ascertained at baseline over 30 days) and key cardiovascular outcomes.

RESULTS

Among 39 710 patients (mean age 77.1±8.7 years, 60.7% male, and a mean CHA₂DS₂-VASc score 4.9±1.3), all-cause mortality at 1-year increased with baseline AF burden: 8.54% with AF burden 0%, 8.9% with AF burden 0% to 5%, and 10.9% with AF burden 5% to 98% (P<0.001) There was also a dose-response relationship between increasing AF burden and all-cause or cardiovascular hospitalization and ischemic stroke. Updating AF burden data every 30 days did not alter the AF burden-prognostic relationships determined from the use of baseline data alone. Results were also consistent when 3-year outcomes were considered and after accounting for the use of oral anticoagulants.

CONCLUSIONS

In paroxysmal AF, there is a clinically relevant dose-response relationship between increasing AF burden and rates of adverse outcomes at 1- and 3-years, including increasing risks of cardiovascular hospitalization, ischemic stroke, and mortality.

Relationship among atrial fibrillation, the CHA2DS2-VASc score and ischaemic stroke in patients with coronary artery disease: a propensity score matching study in Hebei, China

Background

Recent evidence has shown that the pathogenesis of ischaemic stroke associated with atrial fibrillation (AF) is complex and involves other factors in addition to arrhythmias. The purpose of this study was to investigate the relationship among AF, CHA₂DS₂-VASc score and ischaemic stroke in patients with coronary artery disease (CAD) in Hebei, China.

Methods

A total of 2,335 patients with CAD from September 2016 to May 2019 at the Second Hospital of Hebei Medical University were included (mean age 62.73 ± 10.35 years, range 26–92 years; 41.58% female). This was a cross-sectional study, and participants were divided into non-stroke (n = 1997) and ischaemic stroke groups (n = 338). Propensity score matching (PSM) was performed to match ischaemic stroke patients with non-stroke patients in a 1:4 ratio. The relationship among AF, the CHA₂DS₂-VASc score and ischaemic stroke was evaluated using univariable generalized linear models for different sex, age, body mass index (BMI), CAD and CHA₂DS₂-VASc score subgroups. Univariable and multivariable generalized linear models were used to evaluate the relationship between AF and ischaemic stroke in the different models.

Results

Compared with that in the non-stroke group, the prevalence of AF (8.81% vs. 14.20%, P = 0.002) in the ischaemic stroke group was higher. The proportion of patients with ischaemic stroke was significantly different between the AF group and the non-AF group (28.74% vs. 19.04%, P = 0.003). An increasing CHA₂DS₂-VASc score was associated with a gradual increase in the prevalence of AF (P for trend < 0.001). Subgroup analysis showed that the trend towards increased stroke risk in the AF group was consistent across the various subgroups. The multivariable analysis demonstrated that AF was not associated with ischaemic stroke compared with the absence of AF (OR = 1.55, 95% CI 0.94–2.56, P = 0.087).

Conclusion

In our cross-sectional study, after adjustment for confounding factors, there was no association between AF and ischaemic stroke. The increased risk of ischaemic stroke associated with AF was attenuated by atherosclerotic factors. Our study supports the current view that enhanced control of modifiable cardiovascular risk factors in patients with AF is essential.

A Review of Biomarkers for Ischemic Stroke Evaluation in Patients With Non-valvular Atrial Fibrillation

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia worldwide and results in a significantly increased ischemic stroke (IS) risk. IS risk stratification tools are widely being applied to guide anticoagulation treatment decisions and duration in patients with non-valvular AF (NVAF). The CHA₂DS₂-VASc score is largely validated and currently recommended by renowned guidelines. However, this score is heavily dependent on age, sex, and comorbidities, and exhibits only moderate predictive power. Finding effective and validated clinical biomarkers to assist in personalized IS risk evaluation has become one of the promising directions in the prevention and treatment of NVAF. A number of studies in recent years have explored differentially expressed biomarkers in NVAF patients with and without IS, and the potential role of various biomarkers for prediction or early diagnosis of IS in patients with NVAF. In this review, we describe the clinical application and utility of AF characteristics, cardiac imaging and electrocardiogram markers, arterial stiffness and atherosclerosis-related markers, circulating biomarkers, and novel genetic markers in IS diagnosis and management of patients with NVAF. We conclude that at present, there is no consensus understanding of a desirable biomarker for IS risk stratification in NVAF, and enrolling these biomarkers into extant models also remains challenging. Further prospective cohorts and trials are needed to integrate various clinical risk factors and biomarkers to optimize IS prediction in patients with NVAF. However, we believe that the growing insight into molecular mechanisms and in-depth understanding of existing and emerging biomarkers may further improve the IS risk identification and guide anticoagulation therapy in patients with NVAF.

Optimizing indices of AF susceptibility and burden to evaluate AF severity, risk and outcomes

Atrial fibrillation (AF) has heterogeneous patterns of presentation concerning symptoms, duration of episodes, AF burden, and the tendency to progress towards the terminal step of permanent AF. AF is associated with a risk of stroke/thromboembolism traditionally considered dependent on patient-level risk factors rather than AF type, AF burden, or other characterizations. However, the time spent in AF appears related to an incremental risk of stroke, as suggested by the higher risk of stroke in patients with clinical AF vs. subclinical episodes and in patients with non-paroxysmal AF vs. paroxysmal AF. In patients with device-detected atrial tachyarrhythmias, AF burden is a dynamic process with potential transitions from a lower to a higher maximum daily arrhythmia burden, thus justifying monitoring its temporal evolution. In clinical terms, the appearance of the first episode of AF, the characterization of the arrhythmia in a specific AF type, the progression of AF, and the response to rhythm control therapies, as well as the clinical outcomes, are all conditioned by underlying heart disease, risk factors, and comorbidities. Improved understanding is needed on how to monitor and modulate the effect of factors that condition AF susceptibility and modulate AF-associated outcomes. The increasing use of wearables and apps in practice and clinical research may be useful to predict and quantify AF burden and assess AF susceptibility at the individual patient level. This may help us reveal why AF stops and starts again, or why AF episodes, or burden, cluster. Additionally, whether the distribution of burden is associated with variations in the propensity to thrombosis or other clinical adverse events. Combining the improved methods for data analysis, clinical and translational science could be the basis for the early identification of the subset of patients at risk of progressing to a longer duration/higher burden of AF and the associated adverse outcomes.