Evidence-based insights on ideal blanking period duration following atrial fibrillation catheter ablation.

AIMS: Despite the general adoption of a 3-month blanking period (BP), increasing scientific evidence suggests an association between early recurrences of atrial tachyarrhythmias (ERAT) and failure of atrial fibrillation catheter ablation (AFCA). The aim of the present study was to perform a diagnostic meta-analysis to derive the ideal BP cut-off following AFCA. METHODS AND RESULTS: PubMed/MEDLINE databases were screened for articles reporting late recurrences of atrial tachyarrhythmias (LRAT) in AFCA patients experiencing an ERAT (with at least one time cut-off). Seventeen studies were finally included in the analysis, encompassing 5837 AF patients experiencing ERAT after AFCA. A random-effect meta-analysis of diagnostic test accuracy studies with multiple cut-offs was performed. The day at which the ERAT occurred was considered the diagnostic 'test', whereas the different time cut-offs reported in the singular studies were treated as cut-offs of interest in the meta-analysis. Overall, a 27.7 day (95% confidence interval: 10.4-45.1 days) cut-off was identified as the optimal BP duration [area under the summary receiver operating characteristic (AUC-SROC) curve: 0.66, 95% CI: 0.56-0.75]. Specificity (95% CI: 63-85%) and positive predictive value were 76%. At subgroup analysis, the optimal BP cut-off was 39.0 days (95% CI: 26.8-51.2 days, AUC-SROC: 0.63) following radiofrequency AFCA and 30.1 days (95% CI: 0-63.4 days, AUC-SROC: 0.76) after cryoballoon ablation. CONCLUSION: The present meta-analysis indicates that a 4-week BP represents the optimal cut-off following AFCA. Altogether, these meta-analytic insights support the need of a revision of the actual 3-month BP duration.

Atrial Fibrillation and Dementia: Epidemiological Insights on an Undervalued Association.

Background and objectives: Atrial fibrillation (AF) and dementia are growing causes of morbidity and mortality, representing relevant medical and socioeconomic burdens. In this study, based on data from the Global Burden of Disease Injuries and Risk Factors Study (GBD) 2019, we focused on AF and dementia distribution and investigated the potential correlation between the two epidemiological trends. Materials and Methods: Crude and age-standardized incidence, prevalence, mortality rate, and disability-adjusted life years (DALYs) lost, derived from GBD 2019, were reported for AF and dementia. Global features were also stratified by high and low sociodemographic-index (SDI) countries. Granger test analysis was performed to investigate the correlation between AF and dementia incidence time trends. Results: From 1990 to 2019 crude worldwide incidence and prevalence showed a dramatic increase for both conditions (from 43.24 to 61.01 and from 528.72 to 771.51 per 100,000 individuals for AF, respectively; from 54.60 to 93.52 and from 369.88 to 667.2 per 100,000 individuals for dementia, respectively). In the same timeframe, crude mortality rate doubled for AF and dementia (from 2.19 to 4.08, and from 10.49 to 20.98 per 100,000 individuals, respectively). Age-standardized estimate showed a substantial stability over the years, highlighting the key role of the progressively aging population. Crude estimates of all of the investigated metrics are greater in high SDI countries for both conditions. This association was still valid for age-standardized metrics, albeit by a reduced magnitude, suggesting the presence of higher risk factor burden in these countries. Finally, according to Granger test, we found a significant association between the historical trends of AF and dementia incidence (p = 0.004). Conclusions: AF and dementia burden progressively increased in the last three decades. Given the potential association between these two conditions, further clinical data assessing this relationship is needed.

Prognostic implications of atrial fibrillation in patients with stable coronary artery disease: a systematic review and meta-analysis of adjusted observational studies.

Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice. Despite the frequent coexistence with coronary artery disease (CAD), the prognostic independent implication of AF in patients with stable CAD remains controversial. Our aim was to perform a pairwise meta-analysis of adjusted observational studies comparing cardiovascular outcomes in patients with stable CAD with and without concomitant AF, in search of AF-specific prognostic implications. We performed random effect meta-analysis of binary outcome events in studies comparing stable CAD patients with versus without AF providing risk estimates adjusted for confounding variables. Literature search was performed in PubMed/MEDLINE and Google Scholar. Death was the primary endpoint of the analysis, while myocardial infarction, coronary revascularization and stroke secondary endpoints. 5 studies were included in the meta-analysis, encompassing a total of 30230 stable CAD patients (2844 with AF, 27386 without AF). Stable CAD patients with AF presented an independent increased risk of death (HR 1.39, 95% CI: 1.17-1.66) and stroke (HR 1.88, 95% CI: 1.45-2.45) compared to those without AF. Instead, risk of myocardial infarction (HR 0.90, 95% CI: 0.66-1.22) and coronary revascularization (HR 0.96, 95% CI: 0.79-1.16) did not differ in stable CAD patients with and without the arrhythmia. In patients with stable CAD, AF exerts an independent negative prognostic effect, increasing the risk of death and stroke. However, the small number of eligible studies included in this analysis highlights the astonishing lack of data regarding prognostic implications of concomitant AF in patients with stable CAD.

Epicardial Atrial Fat at Cardiac Magnetic Resonance Imaging and AF Recurrence after Transcatheter Ablation.

The relationship between epicardial adipose tissue (EAT) and atrial fibrillation (AF) has gained interest in recent years. The previous literature on the topic presents great heterogeneity, focusing especially on computed tomography imaging. The aim of the present study is to determine whether an increased volume of left atrial (LA) EAT evaluated at routine pre-procedural cardiac magnetic resonance imaging (MRI) relates to AF recurrences after catheter ablation. A total of 50 patients undergoing AF cryoballoon ablation and pre-procedural cardiac MRI allowing quantification of LA EAT were enrolled. In one patient, the segmentation of LA EAT could not be achieved. After a median follow-up of 16.0 months, AF recurrences occurred in 17 patients (34%). The absolute volume of EAT was not different in patients with and without AF recurrences (10.35 mL vs. 10.29 mL; p-value = 0.963), whereas the volume of EAT indexed on the LA volume (EATi) was lower, albeit non-statistically significant, in patients free from arrhythmias (12.77% vs. 14.06%; p-value = 0.467). The receiver operating characteristic curve testing the ability of LA EATi to predict AF recurrence after catheter ablation showed sub-optimal performance (AUC: 0.588). The finest identified cut-off of LA EATi was 10.65%, achieving a sensitivity of 0.5, a specificity of 0.82, a positive predictive value of 0.59 and a negative predictive value of 0.76. Patients with values of LA EATi lower than 10.65% showed greater survival, free from arrhythmias, than patients with values above this cut-off (84% vs. 48%; p-value = 0.04). In conclusion, EAT volume indexed on the LA volume evaluated at cardiac MRI emerges as a possible independent predictor of arrhythmia recurrence after AF cryoballoon ablation. Nevertheless, prospective studies are needed to confirm this finding and eventually sustain routine EAT evaluation in the management of patients undergoing AF catheter ablation.

Role of atrial high-rate episodes in stratifying thromboembolic risk: a multiple cut-off diagnostic meta-analysis.

Aims: Despite the high prevalence rate of atrial high-rate episodes (AHREs) detected using cardiac implantable electronic devices (CIEDs), clinical guidelines and consensus documents have disagreed on a universal AHRE definition and a temporal cut-off related to subsequent thromboembolic events. This diagnostic test accuracy meta-analysis aims to derive the optimal temporal threshold of clinically significant AHREs from the available literature. Methods: The PubMed/MEDLINE and EMBASE databases were screened for studies on CIED patients reporting the incidence of thromboembolic events related to at least one AHRE temporal cut-off. A total of 23 studies were included: 19 considering the longest single AHRE and four the AHRE burden, respectively. A random-effect diagnostic test accuracy meta-analysis with multiple cut-offs was performed. Two analyses were performed according to the AHRE temporal cut-off subtype (longest episode vs. cumulative burden). Results: The analysis on the longest single AHRE indicated 0.07 min as the optimal duration to differentiate AHRE associated or not with thromboembolic events [sensitivity 65.4% (95% CI 48.8%-79.0%), specificity 52.7% (95% CI 46.0%-59.4%), and area under the summary receiver operating characteristic curve (AUC-SROC): 0.62]. The analysis on AHRE burden indicated 1.4 min as the optimal cut-off [sensitivity 58.2% (95% CI 25.6%-85.0%), specificity 57.5% (95% CI 42.0%-71.7%), and AUC-SROC 0.60]. A sensitivity analysis excluding patients with a history of atrial fibrillation and including high-quality studies only yielded similar results. Conclusion: The presence of AHRE, rather than a specific duration, relates to an increased, albeit low, thromboembolic risk in CIED patients. Any AHRE should constitute an additional element in patient-specific thromboembolic risk assessment.

Association of Catheter Ablation and Reduced Incidence of Dementia among Patients with Atrial Fibrillation during Long-Term Follow-Up: A Systematic Review and Meta-Analysis of Observational Studies.

BACKGROUND: Atrial fibrillation (AF) is independently associated with the onset of cognitive decline/dementia. AF catheter ablation (AFCA) is the most effective treatment strategy in terms of sinus rhythm maintenance, but its effects on dementia prevention remain under investigation. The aim of the present study was to perform a systematic review and meta-analysis of the presently available studies exploring the effect of AFCA on dementia occurrence. METHODS: PubMed/MEDLINE databases were screened for articles through 14 March 2022 reporting adjusted time-to-event outcome data comparing AFCA and non-AFCA cohorts in terms of de novo dementia occurrence. A random effect meta-analysis was performed to estimate the meta-analytic hazard ratio (HR) of dementia occurrence in AFCA vs. non-AFCA cohorts, as well as the meta-analytic incidence rate of dementia in the non-AFCA cohort. Based on the aforementioned estimates, the number needed to treat (NNT), projected at median follow-up, was derived. RESULTS: Four observational studies were included in the analysis, encompassing 40,146 patients (11,312 in the AFCA cohort; 28,834 in the non-AFCA cohort). AFCA conferred a significant protection to the development of dementia with an overall HR of 0.52 (95% CI 0.35-0.76). The incidence rate of dementia in the non-AFCA group was 1.12 events per 100 person-year (95% CI 0.47-2.67). The derived NNT projected to the median follow-up (4.5 years) was 41. CONCLUSION: AFCA is associated with a nearly 50% reduction in dementia occurrence during a median 4.5-year follow-up. Future randomized clinical trials are needed to reinforce these findings.