Ablation of atrial fibrillation and dementia risk reduction during long-term follow-up: a nationwide population-based study

Factors associated with cognitive impairment in patients with atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of cognitive impairment. Therefore, exploring factors which may be associated with cognitive impairment is important. Correspondingly, this study aimed to systematically evaluate factors associated with cognitive impairment in AF patients by synthesizing relevant evidence.

METHODS

A database search of the PubMed, Embase, Cochrane Library, Web of Science, CBM, CNKI, Wanfang, and VIP databases was conducted from inception until December 21, 2023. The effect size was expressed as a combined odds ratio (OR) and 95 % confidence interval (95 % CI). The heterogeneity was qualitatively analyzed by Cochran's Q test and quantified by the I2 statistic.

RESULTS

A total of 7,128 studies were identified from the 8 databases, and 39 studies of 3,491,423 participants were included. A meta-analysis was performed on 19 influencing factors. Advanced age (OR=1.38, 95 % CI: 1.11-1.71), female sex (OR=2.19, 95 % CI: 1.18-4.06), smoking (OR=2.44, 95 % CI: 1.24-4.80), hypertension (OR=1.61, 95 % CI: 1.27-2.03), diabetes (OR=1.42, 95 % CI: 1.20-1.67), and hearing impairment (OR=1.37, 95 % CI: 1.05-1.81) were risk factors for cognitive impairment. A higher education level (OR=0.57, 95 % CI: 0.46-0.72), oral anticoagulants (OR=0.61, 95 % CI: 0.48-0.78), novel oral anticoagulants (OR=0.63, 95 % CI: 0.54-0.73), warfarin (OR=0.55, 95 % CI: 0.39-0.79), novel oral anticoagulants relative to warfarin (OR=0.88, 95 % CI: 0.81-0.97), catheter ablation (OR=0.74, 95 % CI: 0.58-0.94) and exercise (OR=0.66, 95 % CI: 0.61-0.72) were protective factors for cognitive impairment.

CONCLUSIONS

Age, sex, education level, smoking, exercise, hypertension, diabetes, hearing impairment, anticoagulation therapy, and catheter ablation were associated with cognitive impairment in AF patients.

Catheter ablation for atrial fibrillation and risk of neurologic disease

Background

Catheter ablation (CA) of atrial fibrillation (AF) has been proven to benefit patients with symptomatic AF and heart failure. However, the data on neurological outcomes including cerebrovascular accidents (CVA) and dementia remain controversial.

Objective

We aimed to determine the effect of CA on neurological events during long-term follow-up.

Methods

We performed a systematic review and meta-analysis of patients with AF who underwent CA of AF. The MEDLINE, EMBASE, and Web of Science databases were comprehensively searched from inception to January 2024. Studies that reported incidence of CVA and dementia in patients with AF were. Data from each study were combined by a random-effects model. The results were reported in risk ratios with 95% confidence intervals (CIs).

Results

A total of 29 studies and 379,993 patients (mean age 58 ± 4 years, 30% women) were included in the analysis. Mean follow-up was 36 ± 23 months (range 12-120 months). Patients who underwent CA of AF had a lower risk of developing CVA compared with medical management (odds ratio [OR] 0.54, 95% CI 0.42-0 69, I2 = 91%). Moreover, the risk of dementia was lower in the CA group compared with medical management (OR 0.51, 95% CI 0.4-0.66, I2 = 74%). The incidence of CVA in the CA group was 1% (95% CI 1%-2%, I2 = 97%), and the incidence of dementia was 2% (95% CI 2%-8%, I2 = 97%).

Conclusion

CA of AF resulted in lower risk of CVA and dementia compared with medical management alone at long-term follow-up.

Atrial Fibrillation Types and Chronic Kidney Disease are Independent Predictors of Atrial Fibrillation Recurrence After Radiofrequency Ablation

Purpose

Atrial fibrillation (AF) is classified into paroxysmal, persistent, long-term persistent, and permanent types. It is commonly treated by radiofrequency ablation (RFA), which is more successful than conventional anti-arrhythmic drugs, but it is still largely unknown whether these beneficial effects are equally present for all AF types. Here, we evaluated the impact that AF type has on post-RFA patient conditions and identified underlying factors affecting AF prognoses.

Patients and Methods

Three hundred and twenty-nine AF patients who underwent RFA were retrospectively examined (221 paroxysmal, 56 persistent, 52 long-term persistent), during a post-RFA follow-up period, from 3-months to 2-years. Cardiac functional parameters, such as left atrial (LA), ventricular (LV), and pulmonary artery diameters, as well as ejection fraction (EF) and end-diastolic/systolic diameter ratio, were measured using echocardiography. Additionally, chronic kidney disease (CKD) was diagnosed among these AF patients, using the Modification of Diet in Renal Disease (MDRD) formula, and its impact on post-RFA patient outcomes was examined. Logistic regression analysis identified differences between AF and non-AF recurrence groups.

Results

In terms of functional parameters, persistent AF had significantly smaller LA, and larger EF, compared to paroxysmal and long-term persistent groups, while paroxysmal had significantly larger LV versus persistent and long-term persistent after RFA. For post-RFA patient conditions, paroxysmal, compared to persistent and long-term persistent, had significantly lower AF recurrence (18.10% versus 30.36% and 36.54%) and re-hospitalization rates (6.79% versus 14.29% and 19.23%); however, no significant difference was present between the 3 groups in terms of post-operative stroke rates, as well as re-hospitalization duration. Additionally, CKD patients, versus non-CKD, were more prone to AF recurrence and re-hospitalization, being 3.268 times more likely.

Conclusion

AF types and CKD were independent factors influencing AF recurrence, serving as highly sensitive predictors to monitor prognoses and guide treatments. Therefore, personalized treatment regimens should be recommended for different AF patients.

Association between Atrial Fibrillation and Risk of Alzheimer's Disease and Vascular Dementia: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Recent research suggests that atrial fibrillation (AF) may influence the risk of developing Alzheimer's disease (AD) and vascular dementia (VaD). However, existing studies have provided inconsistent results, with some showing a significant association between AF and the risk of AD and VaD, while others do not. The objective of this study is to conduct a meta-analysis to investigate the association between AF and the risk of AD and VaD.

METHODS

A comprehensive search was conducted in several databases, including PubMed, Web of Science, Embase, and Google Scholar, covering research published before December 2023. Odds ratios (ORs) or relative risks (RRs) and 95% confidence intervals (CIs) were calculated using Stata 12.0 software to assess the association between AF and the risk of AD or VaD.

RESULTS

The meta-analysis revealed a significant association between AF and an increased risk of AD, using a random effects model (OR/RR: 1.23, 95% CI: 1.13-1.34, I2 = 81.3%, P < 0.001). Similarly, a significant association was found between AF and an increased risk of VaD, using a random effects model (OR/RR: 1.80, 95% CI: 1.57-2.07, I2 = 82.1%, P < 0.001).

CONCLUSION

In summary, our comprehensive meta-analysis provides compelling evidence of a significant association between AF and an elevated risk of AD and VaD. The findings are corroborated by robust cross-sectional and longitudinal cohort studies, which further validate the observed link. However, further large-scale prospective studies are necessary to comprehensively investigate the relationship between AF and the risk of AD and VaD.

Reduced dementia risk in patients with optimized anticoagulation therapy undergoing atrial fibrillation ablation

BACKGROUND

Atrial fibrillation (AF) is associated with the development of dementia, and observational studies have shown that oral anticoagulation and catheter ablation reduce dementia risk. However, such studies did not consistently report on periprocedural anticoagulation and long-term oral anticoagulation coverage, for which reason the separate effect of AF ablation on dementia risk could not be established.

OBJECTIVE

We evaluated the protective effect of AF ablation in a large cohort of patients who received optimized anticoagulation and compared them with patients who were managed medically.

METHODS

We retrospectively included 5912 consecutive patients who underwent first-time catheter ablation for AF between 2008 and 2018 and compared them with 52,681 control individuals from the Swedish Patient Register. Propensity score matching produced 2 cohorts of equal size (n = 3940) with similar baseline characteristics. Dementia diagnosis was identified by International Classification of Diseases codes from the patient register.

RESULTS

Most propensity score-matched patients were taking an oral anticoagulant at the start (94.5%) and end (75.0%) of the study. Mean follow-up was 4.9 ± 2.8 years. Catheter ablation was associated with lower risk for the dementia diagnosis compared with the control group (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.22-0.86; P = .017). The result was similar when including patients with a stroke diagnosis before inclusion (HR, 0.50; 95% CI, 0.28-0.89; P = .019) and after adjustment for the competing risk of death (HR, 0.41; 95% CI, 0.20-0.86; P = .018).

CONCLUSION

Catheter ablation of AF in patients with optimized oral anticoagulation therapy was associated with a reduction in dementia diagnosis, even after adjustment for potential confounders and for competing risk of death.

Microembolizations in the arterial cerebral circulation during atrial fibrillation ablation: cryoballoon technique advantages and neurocognitive safety-results of a prospective observational study

AIMS

The significance of micro-embolic signals (MESs) during atrial fibrillation (AF) ablation is unclear. Previous studies had limitations, and cryoballoon (CB) ablation patients were under-represented. Minimizing MESs is recommended due to their uncertain neurocognitive impact.

METHODS AND RESULTS

This prospective observational study included AF patients from a German centre between February 2021 and August 2022. Patients were equally divided into paroxysmal (Group A) and persistent (Group B) AF. Group A received cryoballoon-pulmonary vein isolation only, while Group B also had left atrial roof ablation. MESs were detected using transcranial Doppler ultrasonography during ablation. Neurocognitive status was assessed pre- and post-procedure and at 3 months using the CERAD Plus battery. The study analyzed 100 patients with a median age of 65.5 years. A total of 19 698 MESs were observed, with 80% being gaseous and 20% solid in origin, primarily occurring during pulmonary vein angiography and the balloon freeze and thawing phase. The median MES per patient was 130 (IQR: 92-256) in total, 298 (IQR: 177-413) in bilateral (36%), and 110 (IQR: 71-130) in unilateral (64%) recordings. No significant difference in total MES counts was found between the groups. None of the 11 neuropsychological tests showed cognitive decline post-procedure or at 3 months.

CONCLUSION

Our observations confirm that neurocognitive abilities are not affected either 24 h or 3 months after AF ablation using the CB technique. However, despite the low MES burden associated with the CB, more work is needed to reduce small embolic events during AF ablation.

Could the Early Detection of Atrial Fibrillation Reduce the Risk of Developing Dementia?

Atrial fibrillation (AF) and dementia are major global public health issues and share common risk factors, especially after the age of 65 and regardless of the presence of stroke. Despite accounting for potential confounders, AF appears to be an independent risk factor for cognitive decline and dementia. The mechanisms are likely to be multifactorial and may include AF-related ischemic stroke, cerebral hypoperfusion, microbleeds, systemic inflammation, genetic factors, and small vessel disease, leading to brain atrophy and white matter damage. The early aggressive management of AF and comorbidities may reduce the risk of dementia. Indeed, the early detection of AF-related cognitive impairment should allow for the early implementation of measures to prevent the development of dementia, mainly through integrative approaches involving the correction of risk factors and maintenance of rhythm control. Well-designed prospective studies are needed to determine whether early detection and AF treatment can prevent dementia and identify whether optimal integrative measures are effective in preventing cognitive impairment and dementia.

Ocular blood flow dynamics following sinus rhythm restoration through catheter ablation: laser speckle flowgraphy in patients with persistent atrial fibrillation

Aims

Laser speckle flowgraphy (LSFG) is a well-established tool renowned for its non-invasive and reproducible assessment of ocular blood flow. While rhythm control therapies, such as catheter ablation (CA), have shown promise in enhancing cognitive function in atrial fibrillation (AF) patients, the acute impact of CA on microcirculatory changes, particularly in ocular blood flow, remains a topic of limited understanding. The present study aims to delve into the potential of LSFG in detecting microcirculatory alterations following the restoration of sinus rhythm (SR) through CA in patients with AF.

Methods and results

We studied 8 paroxysmal AF (Paf) and 20 persistent AF (PeAF) patients (mean age 67 ± 6 years, 26% female) undergoing CA. Ocular blood flow was assessed using LSFG by measuring the mean blur rate (MBR) pre- and post-CA. Post-CA, all PeAF patients achieved SR restoration, resulting in a significant increase in tissue MBR (10.0 ± 2.2 to 10.8 ± 2.9, P = 0.021). In contrast, Paf patients showed no significant difference between pre- and post-MBR (12.0 ± 2.7 vs. 11.8 ± 2.6, P = 0.76).

Conclusion

LSFG analysis effectively identified microcirculatory changes in patients undergoing CA for PeAF, suggesting that therapeutic interventions targeting the heart may have broader implications for ocular and cerebral health, establishing a novel 'cardio-oculo-cerebral relationship'.

Impact of Helicobacter pylori and metabolic syndrome on mast cell activation-related pathophysiology and neurodegeneration

Both Helicobacter pylori (H. pylori) infection and metabolic syndrome (MetS) are highly prevalent worldwide. The emergence of relevant research suggesting a pathogenic linkage between H. pylori infection and MetS-related cardio-cerebrovascular diseases and neurodegenerative disorders, particularly through mechanisms involving brain pericyte deficiency, hyperhomocysteinemia, hyperfibrinogenemia, elevated lipoprotein-a, galectin-3 overexpression, atrial fibrillation, and gut dysbiosis, has raised stimulating questions regarding their pathophysiology and its translational implications for clinicians. An additional stimulating aspect refers to H. pylori and MetS-related activation of innate immune cells, mast cells (MC), which is an important, often early, event in systemic inflammatory pathologies and related brain disorders. Synoptically, MC degranulation may play a role in the pathogenesis of H. pylori and MetS-related obesity, adipokine effects, dyslipidemia, diabetes mellitus, insulin resistance, arterial hypertension, vascular dysfunction and arterial stiffness, an early indicator of atherosclerosis associated with cardio-cerebrovascular and neurodegenerative disorders. Meningeal MC can be activated by triggers including stress and toxins resulting in vascular changes and neurodegeneration. Likewise, H.pylori and MetS-related MC activation is linked with: (a) vasculitis and thromboembolic events that increase the risk of cardio-cerebrovascular and neurodegenerative disorders, and (b) gut dysbiosis-associated neurodegeneration, whereas modulation of gut microbiota and MC activation may promote neuroprotection. This narrative review investigates the intricate relationship between H. pylori infection, MetS, MC activation, and their collective impact on pathophysiological processes linked to neurodegeneration. Through a comprehensive search of current literature, we elucidate the mechanisms through which H. pylori and MetS contribute to MC activation, subsequently triggering cascades of inflammatory responses. This highlights the role of MC as key mediators in the pathogenesis of cardio-cerebrovascular and neurodegenerative disorders, emphasizing their involvement in neuroinflammation, vascular dysfunction and, ultimately, neuronal damage. Although further research is warranted, we provide a novel perspective on the pathophysiology and management of brain disorders by exploring potential therapeutic strategies targeting H. pylori eradication, MetS management, and modulation of MC to mitigate neurodegeneration risk while promoting neuroprotection.

Atrial fibrillation increases the risk of all-cause dementia, Alzheimer's disease, and vascular dementia: A cohort study of 373, 415 participants in the UK Biobank

BACKGROUND

Accumulated evidence has highlighted the association between atrial fibrillation and the risk of developing dementia.

METHODS

This current cohort study utilized data from the UK Biobank to explore the association between atrial fibrillation (AF) and all-cause dementia (ACD), encompassing its main subtypes (Alzheimer's disease (AD), and vascular dementia (VD)). Cox proportional hazards models were applied to examine the association of AF and dementia with its primary subtypes after adjusting for different sets of covariates. Hazard ratios (HRs) with 95 % confidential intervals (CIs) were estimated to quantify the associated risks. Competing risk model was applied in sensitivity analysis.

RESULTS

After exclusion, 373, 415 participants entered the primary analysis. Among these, 27, 934 (7.48 %) were with a history AF at baseline, while 345, 481 (92.52 %) were without. During a mean follow-up of 13.45 years, ACD was diagnosed in 1215 individuals with AF and 3988 individuals without AF. Participants with AF had higher risks of ACD (1.79 [1.67-1.91]), AD (1.48 [1.32-1.65]), and VD (2.46 [2.17-2.80]) in the fully adjusted Cox regression models. Results of subgroup and sensitivity analyses predominantly aligned with the positive associations in primary analysis.

LIMITATIONS

The applicability of our findings to diverse ethnicities might require careful consideration and the behind biological mechanisms need to be further revealed.

CONCLUSIONS

It indicated that people with atrial fibrillation had an increased future risk of all-cause dementia, Alzheimer's disease, vascular dementia. Atrial fibrillation screening and prevention strategies should take into account to prevent and delay the onset of dementia.

Effects of rhythm-control and rate-control strategies on cognitive function and dementia in atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Growing evidence suggests that atrial fibrillation (AF) is an independent risk factor for cognitive impairment and dementia, even in the absence of thromboembolic events and stroke. Whether rhythm-control therapy can protect cognitive function remains unclear. We aimed to evaluate the efficacy of rhythm-control strategies in patients with AF regarding cognitive function and dementia risk.

METHODS

We systematically searched the PubMed, Embase and Cochrane Library databases for randomised clinical trials, cohort and case-control studies evaluating the associations between rhythm-control strategies and cognitive function outcomes up to May 2023. We assessed the risk of bias using the ROBINS-I and the Cochrane risk-of-bias tool. Both fixed- and random-effects models were used to create summary estimates of risk.

RESULTS

We included a total of 14 studies involving 193,830 AF patients. In the pooled analysis, compared with rate-control, rhythm-control therapy was significantly associated with a lower risk of future dementia (hazard ratio (HR) 0.74; 95% confidence interval (CI) 0.62-0.89; I2 = 62%). Among the rhythm-control strategies, AF ablation is a promising treatment that was related to significantly lower risks of overall dementia (HR 0.62; 95% CI 0.56-0.68; I2 = 42%), Alzheimer's disease (HR 0.78; 95% CI 0.66-0.92; I2 = 0%) and vascular dementia (HR 0.58; 95% CI 0.42-0.80; I2 = 31%). Pooled results also showed that compared with patients without ablation, those who underwent AF ablation had significantly greater improvement in cognitive score (standardized mean difference (SMD) 0.85; 95% CI 0.30-1.40; P = 0.005; I2 = 76%).

CONCLUSIONS

Rhythm-control strategies, especially ablation, are effective in protecting cognitive function, reducing dementia risk and thus improving quality of life in AF patients.

Epidemiology, Trends, Utilization Disparities, and Outcomes of Catheter Ablation and Its Association With Coronary Vasospasm Amongst Patients With Non-valvular Atrial Fibrillation: A Nationwide Burden of Last Decade

BACKGROUND

Catheter ablation (CA) is an important curative treatment for non-valvular atrial fibrillation (NVAF), however, nationwide data on its utilization and disparities is limited. Coronary vasospasm is a rare, life-threatening, peri-operative complication of CA with limited literature in Caucasians.

METHODS

We performed a retrospective study on adult hospitalizations in the USA from 2007 to 2017 by obtaining the data from National Inpatient Sample. The primary endpoints of our study were to identify the utilization rate of CA, disparities in utilization, and study the outcomes associated with CA. The secondary endpoints of the study were to identify the incidence of coronary vasospasm amongst patients who underwent CA, evaluate their association, and identify the predictors of coronary vasospasm.

RESULTS

From 35,906,946 patients with NVAF, 343641 (0.96%) underwent CA. Its utilization decreased from 1% in 2007 to 0.71% in 2017. Patients who underwent CA, compared to those without CA, fared better in terms of hospital length of stay, mortality rate, disability rate, and discharge to the non-home facility. Patients in the 50-75 years age group, Native Americans, those with private insurance, and median household income of 76-100th percentile were associated with higher odds of CA utilization. Urban teaching hospitals and large-bedded hospitals performed more ablations, while the Mid-West region fared lower than the South, the West, and the Northeast. The prevalence of coronary vasospasm was higher amongst CA in comparison without CA, however, in regression analysis, no significant association was demonstrated between CA and coronary vasospasm.

CONCLUSION

CA is an important treatment modality that is associated with improved clinical outcomes. Identification of factors associated with lower utilization of CA and its disparities will help to mitigate the burden associated with NVAF.