Atrial High-rate Episodes Research Articles

Anticoagulation in patients with atrial high-rate episodes.

Anticoagulation in patients with atrial high-rate episodes.

Are device-detected atrial high-rate episodes a risk marker for stroke?

Are device-detected atrial high-rate episodes a risk marker for stroke?

The impact of the right heart cavities echocardiographic features on atrial-high rate episodes.

Atrial high-rate episodes (AHRE) defined as atrial tachy-arrhythmias, detected through continuous monitoring with a cardiac implantable electronic device (CIED). AHRE's have been associated with increased risks of developing clinically manifested atrial fibrillation, thromboembolism, cardiovascular events, and mortality. Several variables have been researched and identified to predict AHRE existence. The present study evaluated the association between right-heart structural and functional echocardiographic parameters and AHRE in patients with CIEDs and impaired LVEF.This prospective design study included 194 patients with CIED's. The study population was divided into two groups according to presence of AHRE and analyzed the echocardiographic variables which may able to be a predictor of AHRE.Patients was divided into two groups: patients with AHRE (+) and without AHRE (-). The distribution of patients' characteristics according to presence of AHRE was analyzed. The multivariate analysis revealed Age, LAVI, E/Em tricuspid (HR: 1.106, 1.015-1.205% 95 CI;p = 0.022) and RAVI (HR: 1.035, 1.003-1.069 95% CI;p = 0.033) as independent predictors of AHREs. ROC curve analysis indicated that an E/Em tricuspid (AUC: 0.611, 95% CI 0.538-0.680 p: 0.009) and RAVI (AUC = AUC: 0.707, 95% CI 0.637-0.770 p < 0.001) predicted AHREs with a cut-off value of 6.28 and a sensitivity of 53.2% and specificity of 66.7% and a cut-off value of 29.5 mL/m2 with a sensitivity of 72.7% and a specificity of 65.9%, respectively.The main finding of this study was "RAVI" and "E/Emtricuspid ratio" is associated with AHRE. Additionally, "RAVI" and "E/Emtricuspid ratio" is an independent predictor of AHRE existence.

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

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. 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. 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). 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.

Association of device detected atrial high rate episodes with embolic events

Abstract Background Subclinical atrial fibrillation (AFib) is a common etiology of embolic events such as embolic strokes of undetermined source. With the advent of cardiac implantable electronic devices (CIED), there has been increased detection of subclinical AFib, or atrial high rate episodes (AHRE) in asymptomatic patients without a known diagnosis of AFib. The clinical significance of AHRE detected with CIED remains poorly characterized with studies reporting conflicting results. The purpose of this meta-analysis is to evaluate the association of AHRE with cerebrovascular accidents (CVA), transient ischemic attacks (TIA), and systemic embolic events. Methods A literature search was conducted for studies reporting on the association of subclinical AFib or AHRE with CVA, TIA, and systemic embolic events. The search included the following databases: Ovid MEDLINE, EMBASE, Google Scholar, and Web of Science. The search was not restricted to time or publication status. Results A total of 19 studies and 50,968 patients (12,879 with AHRE vs 38,089 without AHRE) were included. Mean follow-up was 32 months, mean age was 72 years old, 53.3% were male. Patients with device detected AHRE had increased risk of composite endpoint of CVA, TIA, and systemic embolic events (OR 2.98, 95% CI 2.03-4.39; P&amp;lt;0.01). Subgroup analysis by maximum AHRE burden demonstrated that both maximum AHRE burden &amp;gt;24 hours and burden &amp;lt;24 hours are associated with increased risk of CVA, TIA, and systemic embolic events (OR 4.82, 95% CI 2.07-11.24; p&amp;lt;0.01; OR 1.55, 95% CI 1.11-2.15; p&amp;lt;0.01). The overall effect size is larger for maximum AHRE burden &amp;gt;24 hours compared to &amp;lt;24 hours (Z=3.64 vs Z=2.61). Conclusions Our results suggest that AHRE detected with CIED is associated with increased risk of CVA, TIA, and systemic embolic events regardless of maximum AHRE burden &amp;gt;24 hours or &amp;lt;24 hours. Additional studies are required to determine the utility anticoagulation therapy for treatment of asymptomatic patients with device detected AHRE.

A multiple cut-off diagnostic meta-analysis to identify the atrial high-rate episodes threshold that better relates to thromboembolic events

Abstract Background Despite the high prevalence of atrial high-rate episodes (AHRE) detected by cardiac implantable electronic devices (CIED), clinical guidelines and consensus documents have failed to agree on a universal AHRE definition. Clear evidence on the best management strategy is lacking. Purpose The present is a diagnostic test accuracy meta-analysis aiming to derive from available literature the optimal AHRE threshold to predict thromboembolic events. Methods PubMed/MEDLINE and EMBASE databases were screened for studies on CIED patients reporting incidence of thromboembolic events referred to at least one AHRE definition. A random-effect diagnostic test accuracy meta-analysis with multiple cut-offs was performed: duration of AHRE was the "diagnostic test" (positive test if the patients experienced an AHRE lasting at least as long as the time cut-off under examination) whose performance in predicting the "disease" (thromboembolic events) was evaluated across multiple cut-offs. Two analyses, according to AHRE definition (longest episode vs. cumulative burden), were performed. Results 23 studies were included in the analyses (Fig. 1 Panel A), encompassing 46,189 patients: 19 considering the longest single AHRE and 4 the AHRE burden, respectively. Median follow-up was 40.75 (IQR 28.25-52.80) months. The analysis on the longest single AHRE indicated 0.07 minutes as the optimal cut-off to differentiate AHRE associated or not to thromboembolic events [sensitivity 65.4% (95% CI 48.8-79.0%), specificity 52.7% (95%CI 46.0-59.4%), area under the summary receiver operating characteristic curve (AUC-SROC): 0.62; Fig. 1 Panel B]. The analysis on AHRE burden indicated, instead, 1.4 minutes as the optimal cut-off [sensitivity 58.2% (95%CI 25.6-85.0%), specificity 57.5% (95% CI 42.0-71.7%), AUC-SROC 0.60; Fig. 1 Panel C]. PPV and NPV for 6 minutes and 24 hours cut-offs were similar in each analysis (Figure 2). Sensitivity analyses exclusively considering studies reporting data on patients without previous AF diagnosis and high-quality studies only yield similar results. Conclusion The present evidence-based approach suggests the presence (or not) of AHRE, rather than a specific duration, relates to an increased thromboembolic risk in CIED patients. A linear relationship between AHRE duration (both in terms of single longest episode than cumulative burden) and thromboembolic events was not observed.

Long duration of atrial high-rate episode is more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score.

This study aimed to explore the roles of duration and burden of atrial high-rate episode (AHRE) on ischemic stroke in patients with pacemaker implantation. Patients with pacemaker implantation for bradycardia from 2013 to 2017 were consecutively enrolled. Data such as gender, age, combined diseases, type of AF, left atrial size, left ventricular size, left ventricular ejection fraction, CHA2 DS2 -VASc score, and anticoagulants were collected. The burden and duration of AHRE based on different interval partition were also recorded in detail to evaluate the impacts on ischemic stroke. Cox regression analysis with time-dependent covariates was conducted. A total of 220 patients with AHRE were enrolled. The average follow-up time was 48.42±17.20 months. Univariate regression analysis showed that diabetes (p=.024), high CHA2 DS2 -VASc score (≥ 2) (p=.021), long mean AHRE burden (p=.011), long maximal AHRE burden (p=.015), long AHRE duration lasting≥48h (p=.001) or 24h (p=.001) or 12h (p=.005) were prone to ischemic stroke. Further multivariate regression analysis showed that long duration of AHRE (≥48h) (HR 10.77; 95% CI 3.22-55.12; p=.030) were significantly correlated with stroke in patients with paroxysmal AF. There was no significant correlation between the type of AF and stroke (p=.927). The longer duration of AHRE (≥48h) was more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score (≥2).

Performance of a multisensor implantable defibrillator algorithm for HF monitoring in the presence of atrial fibrillation

Abstract Background Some implantable cardioverter defibrillators (ICD) are equipped with diagnostic algorithms that combine data from multiple sensors. The HeartLogic Index was shown to accurately stratify patients at risk of heart failure (HF) events. However, there are no data on its performance in the presence of atrial fibrillation (AF). We evaluated and compared the performance of the algorithm during sinus rhythm and during long-lasting AF episodes. Methods The feature was activated in 568 ICD patients from 26 centers. We analyzed stored data to identify periods of ≥30 consecutive days with atrial high-rate episode (AHRE) burden &amp;lt;1hour/day, and periods with AHRE burden ≥20hours/day. Then, we identified patients who met both conditions during their follow-up (AHRE group, N=53), to allow pairwise comparison of periods. For control purposes, we identified patients with AHRE burden &amp;lt;1h during the entire follow-up and we implemented a 2:1 propensity score matching versus the AHRE group (Matched non-AHRE group, N=106). Results In the AHRE group, the rate of HeartLogic alerts was 1.2 (95%CI:1.0-1.5) /patient-year during periods with AHRE burden &amp;lt;1hour/day and 2.0 (95%CI:1.5-2.6) /patient-year during AHRE burden ≥20hours/day periods (p=0.004). Significantly higher values of the combined index were recorded during periods with AHRE burden ≥20 hours/day (in Figure the average combined index – Day 0: alert day). The rate of HF hospitalizations was 0.34 (95%CI:0.15-0.69) /patient-year during IN-alert periods and 0.06 (95%CI:0.02-0.14) /patient-year during OUT-of-alert periods (p&amp;lt;0.001). The IN/OUT-of-alert state incidence rate ratio of HF hospitalizations was 8.59 (95%CI:1.67-55.31) during periods with AHRE burden &amp;lt;1hour/day and 2.70 (95%CI:1.01-28.33) during AHRE burden ≥20hours/day periods. In the Matched non-AHRE group, the rate of HF hospitalizations was 0.29 (95%CI:0.12-0.60) /patient-year during IN-alert periods, and 0.04 (95%CI:0.02-0.08) /patient-year during OUT-of-alert periods (p&amp;lt;0.001). The incidence rate ratio was 7.11 (95% CI: 2.19-22.44). Conclusions Patients seemed more exposed to alerts during periods of AF. The ability of the algorithm to identify increased risk of HF events was confirmed during AF, despite a lower IN/OUT-of-alert incidence rate ratio when compared to non-AF periods and non-AF patients.

Apixaban for TreatmenT of embolIC stroke of Undetermined Source - ATTICUS randomized trial - explorative analysis of AF burden in the ATTICUS cohort

Abstract Background Secondary prevention after embolic stroke of undetermined source (ESUS) has not yet been established. It is likely that a relevant number of ESUS patients have significant episodes of atrial fibrillation (AF) that is not detected by conventional Holter ECGs. Despite high prevalence of occult atrial fibrillation , secondary prevention with acetylsalicylic acid (ASA) is the current standard therapy in ESUS patients. The ATTICUS cohort has been selected for prevalence of at least one suggestive risk factor for cardiac embolism (RF) creating an enriched ESUS population. Purpose This work aims to evaluate overall AF burden in the ATTICUS cohort; to determine the correlation between AF detection and new ischemic lesions; and to explore predictors for atrial fibrillation within the enriched ESUS population. Methods The study enrolled ESUS patients with a risk profile for cardiac thromboembolism. Patients were randomized 1:1 into the ASA or apixaban arm, respectively. Study drug was initiated within 3–28 days after minor/moderate stroke and 14–28 days after major stroke. Cardiac monitoring by either implantable or mobile ECG devices was required during the follow up period. MRI (Flair/DWI) was conducted within 7 days of AF detection and 12 months after randomization. Results Enrollment was stopped after interim analysis including 200 patients, due to futility. Overall, 373 patients were screened with 352 being enrolled in the ITT population (178 and 174 in apixaban and ASA arms, respectively). Mean age of the ATTICUS population was 68.4 years with 51.4% males. 86.1% of the subjects suffered from hypertension. 63.4% of the population showed only one RF, all others showed two or more RFs, whereof most common were CHA2DS2-VASc ≥ 4 (93.8%), PFO (20.5%) and atrial high-rate episodes (AHRE, 13.1%). Analysis of the correlation of AF with each suggestive RF revealed an increased AF detection rate with increased amount of RF (Figure 1) and the most predictive RF to be atrial high-rate episodes. Prevalence of AF increased the risk for new embolic ischemic lesions (OR 2.05 (95% 1.01–4.15)). Newly detected AF was reported in 89 patients (25.3%), 49 occurring in the ASA arm, leading to an immediate switch (from ASA to) apixaban, as required by protocol. Conclusions In contrast to the recently published NAVIGATE and RESPECT ESUS trials, patients enrolled in ATTICUS had to exhibit additional predicting factors for (but no previously diagnosed) AF. These were significantly associated with the incidence of clinical AF with AHRE as the strongest predictor. Continuous cardiac remote monitoring will help to elucidate the AF burden and risk for stroke recurrence in this cohort and the effects of early oral anticoagulation with apixaban compared to antiplatelet therapy with ASA on the incidence of stroke recurrence.

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

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. 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). 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. 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.

The relationship of epicardial fat and atrial high-rate episodes in patients with permanent pacemaker

Objectives: Atrial high-rate episodes (AHRE) can occur in patients who have permanent pacemakers (PPM). AHRE is classified as subclinical atrial fibrillation (AF). Also, AHRE is related to clinical AF. Epicardial fat tissue (EFT) thickness is linked to AF. The purpose of this study was to examine the relation between AHRE and EFT thickness in PPM patients. Methods: Forty patients with dual-chamber PPM were enrolled. Transthoracic echocardiography was used to measure the thickness of the EFT. Patients were examined in 2 groups according to whether there was AHRE in the records: group 1 (AHRE) and group 2 (AHRE-free). A high atrial rate of more than 175 beats per minute for more than 5 minutes was defined as AHRE. The findings of the standard 2-dimensional echocardiography and the Doppler echocardiography were all recorded. A statistical relationship between EFT thickness and the development of AF was investigated. Results: Group 1 had ten patients, while Group 2 included thirty individuals. When the demographic features of the two groups were compared, they were similar. Both groups had similar 2-D echocardiographic and Doppler results. The difference in EFT thickness between groups 1 (2.0 ± 1.1 mm) and 2 (2.9 ± 1.8 mm) was not statistically significant (p = 0.138). Conclusions: In patients with PPM, AHRE may develop after implantation and may be detected asymptomatically in periodic follow-up. In this population, we did not observe a significant association between EFT thickness and the development of AF.

Monocyte/High-Density Lipoprotein Ratio Is Associated with Atrial High-Rate Episodes within One Year Detected by Cardiac Implantable Electronic Devices.

To investigate the risk factors for predicting atrial high-rate episodes (AHREs) detected by cardiac implantable electronic devices (CIEDs). A total of 140 patients with CIED in our hospital from June 2013 to June 2018 were included and were followed up to observe whether they had AHREs. AHRE are defined as atrial rate ≥ 175 times/minute, lasting > 5 minutes, and reviewed by an experienced electrophysiologist with unclear clinical diagnosis. The patients fasted for 12 hours after implantation, and blood samples were collected for biochemical, lipid, and whole blood count detection. Follow-up was regular after discharge to record follow-up data of each patient and conduct statistical analysis. One hundred and forty patients were implanted with dual-chamber pacemakers, their median age was 70 years old, 44.29% were male, 27 patients had AHRE within one year, and AHRE incidence rate was 19.29%. The microcytic to hypochromic (M/H) ratio was calculated for all AHRE patients and compared with the patients without AHRE; the M/H value of AHRE patients was significantly higher. Throughout the entire follow-up period, a total of 44 patients developed AHRE; when adjusted by multivariate analysis, only M/H ratio ≥ 4.5 vs. < 4.5 had statistical significance, and the adjusted hazard ratio value was 4.313 (1.675-11.105). As an indicator, M/H ratio may play an important role in the occurrence and development of atrial fibrillation and can be used as a predictor of AHRE in patients with CIED.

Oral Anticoagulation in Patients With Atrial High-Rate Episodes: Focus on Clinical Implications.

Background Although previous studies showed that atrial high-rate episodes (AHREs) are associated with a higher risk of developing incident atrial fibrillation (AF) and thromboembolic events, their clinical significance is still unclear. The purpose of this study was to define whether there is any clinical impact on the occurrence of ischemic and hemorrhagic events in patients with AHREs and initiation of oral anticoagulation (OAC). Methodology Patients with AHREs who had received cardiac implantable electronic devices (CIEDs, i.e., dual-chamber pacemaker [PM] or implantable cardioverter defibrillator [ICD])were included in the study. OAC initiation was decided by the assistant doctor. Patients who received OACs comprised the OAC group, while patients who were not referred for OAC initiation were included in the control group. The primary endpoint was the time to the event of the occurrence of thromboembolic events (thromboembolic event-free survival). Results A total of 154 individuals (77 in each group) were enrolled in the study, with a mean age of 72.5 years. The mean follow-up period for the OAC group was 19.1 months and for the control group, 18.9 months (P =0.9). Thromboembolic events were noticed only in seven patients. Six of them were in the control group, and only one in the OAC group (P =0.05). Major bleeding events were noticed in five patients, one of whom was in the control group and the rest in the OAC group (P =0.17). Conclusions OAC therapy in patients with AHREs was not associated with a significant difference in the risk of thromboembolic and bleeding events. Baseline patient characteristics and AHRE duration may be useful to intensify the monitoring and management of patients with AHREs. Bleeding events may be indicators of cancer in patients with AHREs receiving OACs.

Association between alcohol consumption and subclinical atrial fibrillation

BackgroundIt has become important to identify and manage risk factors for subclinical atrial fibrillation (AF) with an increase in its detection rate. Thus, this research aimed to investigate whether alcohol consumption contributes to the development of subclinical AF.MethodsThis prospective study enrolled 467 patients without AF from a multicenter pacemaker registry. The incidence of subclinical AF (episodes of atrial rate > 220 beats per minute without symptoms) was compared between alcohol-drinking and non-drinking groups.ResultsDuring followup (median 18 months), the incidence and risk of long-duration atrial high-rate episodes (AHRE) ≥ 24 h were increased in the alcohol group compared to the non-alcohol group [5.47 vs. 2.10 per 100 person-years, adjusted hazard ratio (HR), 2.83; 95% confidence interval (CI), 1.14–7.04; P = 0.03]. After propensity score matching, the incidence and risk of long-duration AHRE were higher in the alcohol group (6.97 vs. 1.27 per 100 person-years, adjusted HR, 7.84; 95% CI, 1.21–50.93; P = 0.03). The mean burden of long-duration subclinical AF was higher in the alcohol group than in the non-alcohol group (0.18 vs. 1.61% during follow-up, P = 0.08).ConclusionAlcohol consumption was associated with an increased risk of subclinical AF. Long-duration AHRE incidence and AHRE burden were higher in alcohol drinkers than in non-drinkers.

Assessment of the efficacy of the electrocardiographic P-wave peak time in predicting atrial high rate episode in patients with cardiac implantable electronic devices.

The incidence of atrial high-rate episode (AHRE) is high among patients with cardiac implantable electronic devices (CIEDs). In this context, the objective of this study is to evaluate the efficacies of P-wave indices (PWIs) obtained from the surface electrocardiography (ECG) in predicting future AHRE development. The study sample consisted of 158 patients with CIEDs. The study group was divided into two subgroups according to the presence of AHRE during device interrogation. PWIs were calculated using the surface ECG. There was no significant difference between the groups in the P-wave indices (PWIs), i.e., minimum P-wave duration (PWDmin), maximum P-wave duration (PWDmax) and P-wave dispersion (PWDIS). On the other hand, P-wave peak time in V1 lead (PWTV1) and P-wave peak time in D2 lead (PWPTD2) were significantly higher in the AHRE group than in the non-AHRE group. The study findings revealed that novel ECG parameters PWPTV1 and PWPTD2 had high prognostic value in predicting patients likely to develop AHRE.

Progression of Device-Detected Atrial High-Rate Episodes and the Risk of All-Cause Mortality

Atrial high-rate episodes (AHREs) are prevalent in approximately 1/3 of patients with cardiac implanted electronic devices and are associated with an increased risk of several adverse outcomes. This study aimed to explore the factors associated with AHRE progression and the risk of all-cause mortality. At least 1day with AHRE burden ≥15minutes was identified in 124 of 343 recipients (36.2%) of an implantable cardioverter defibrillator or cardiac resynchronization therapy device. We included patients whose AHRE burden at the time of first detection was ≥15minutes but <24hours (n=107). Various cut-off values (15minutes, 6hours, and 24hours) of daily AHRE burden were analyzed. During an average follow-up of 4.2years, 60 patients (56.1%) experienced ≥1 progression to greater AHRE burden. Patients with hypertension or greater AHRE burden at first detection were associated with faster progression. In addition, 27 deaths (45%) occurred among 60 patients with AHRE progression, compared with 25.5% (12 of 47) for those without progression. After multivariable adjustment, AHRE progression was independently associated with all-cause mortality (hazard ratio 2.56, 95% confidence interval 1.23 to 5.35, p=0.012). Notably, AHRE progression within 1month after their first detection was associated with an increased risk for all-cause mortality (hazard ratio 4.01, 95% confidence interval 1.76 to 9.16, p=0.001) compared with patients without progression. However, a similar risk was not observed among patients with AHRE progression occurring after 1month after their first detection. In conclusion, >1/2 of the patients with AHRE progressed to a greater burden over time. Continuous monitoring of the AHRE burden may help identify patients at great risk for death.

Initial heart rate score predicts new-onset atrial tachyarrhythmias in pacemaker patients.

Heart rate score (HRSc), the per cent of atrial paced and sensed event in the largest 10 b.p.m. rate histogram bin of a pacemaker, predicts survival in patients with cardiac devices. No correlation between HRSc and development of atrial fibrillation (AF) has been reported. In this study, we evaluated the relationship between pacemaker post-implantation HRSc and the incidence of newly developed atrial tachyarrhythmias (ATAs). Patients with dual-chamber pacemakers, implanted 2013-17, with the LATITUDE remote monitoring data with ≥600 000 beats of histogram data collected at baseline were included (N = 34 543). Heart rate score was determined from the initial 3-month post-implantation histogram data. Patients were excluded if they had ATAs, defined as atrial high-rate episodes >5 min or >1% of right atrial beats >170 b.p.m. during the initial 3 months post-implantation. New ATAs, after the baseline period, were defined by each of the following: >1, >10, or >25% of atrial beats >170 b.p.m. or atrial tachycardia response (ATR) events >24 h. Patients were followed a median of 2.8 (1.0-4.0) years. The incidence of ATAs increased in proportion to HRSc (log-rank P-value <0.001), and the initial HRSc ≥70% was associated with increased ATAs by all definitions. Patients with initial HRSc ≥70% were older, had a higher percentage of right atrium pacing (%RA pacing), had a lower percentage of right ventricular pacing (%RV pacing), and were more likely programmed with rate-response vs. subjects with HRSc <70%. Initial HRSc (hazard ratio: 1.07, 95% confidence interval: 1.05-1.09; P < 0.0001) independently predicted ATAs after adjusting for age, gender, %RV pacing, and rate-response programming. The %RA pacing and initial HRSc were correlated. Heart rate score independently predicts any subsequent duration of ATAs in pacemaker patients.

New-onset atrial high-rate episodes between his bundle pacing and conventional right ventricular septum pacing in patients with atrioventricular conduction disturbance.

The effect of His bundle pacing (HBP) on the incidence of new-onset atrial fibrillation (AF) after pacemaker implantation (PMI) for atrioventricular conduction disturbance (AVCD) remains unknown. We compared the incidence of new-onset atrial high-rate episode (AHRE) in conventional right ventricular (RV) septum pacing (RVSP) and His bundle pacing (HBP) after PMI for AVCD. One hundred and four consecutive patients who underwent dual chamber PMI for AVCD in our hospital were screened. Thirty-five patients with mitral or aortic valve disease, history of open-heart surgery, prior AF, subclinical AF, cumulative ventricular pacing percentage < 90%, and RV lead revision were excluded, and 69 patients were effectively enrolled in this study. The primary endpoint was new-onset AHRE within the follow-up period. New-onset AHRE was defined as an atrial high-rate episode that occurred 3months after PMI and lasted for > 6min at an atrial heart rate > 190bpm. RV leads were placed in the His bundle region and RV septum region in 22 and 47 patients, respectively. The mean follow-up period was 539 ± 218days. The follow-up period was 2years after PMI or until the new-onset AHRE occurred. The incidence of new-onset AHRE was lower in the HBP group than in the RVSP group (11% vs. 43%, p = 0.01). Multivariate analysis in the Cox regression hazard model showed that HBP had a significantly lower risk of new-onset AHRE compared with RVSP (HR = 0.21; 95% confidence interval 0.04-0.78, p = 0.02). The incidence of new-onset AHRE was significantly less in HBP compared to RVSP during the 2-year follow-up period after pacemaker implantation in AVCD patients with RV pacing dependence.

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.

Value of ATRIA stroke risk score in predicting atrial high-rate episodes: A comparison of six different risk scores.

Atrial high-rate episodes (AHRE) are asymptomatic atrial tachy-arrhythmias detected through continuous monitoring with a cardiac implantable electronic device (CIED). AHRE's have been associated with increased risks of developing clinically manifested atrial fibrillation (AF), thromboembolism, cardiovascular events, and mortality. Several variables has been researched and identified to predict AHRE development. The aim of this study, which compared the six frequently-used scoring systems for thromboembolic risk in AF (CHA2 DS2 -VASc, mC2 HEST, HAT2 CH2 , R2 -CHADS2 , R2 -CHA2 DS2 -VASc, and ATRIA) in terms of their prognostic power in predicting AHRE. This retrospective study included 174 patients with CIED's. The study population was divided into two groups according to presence of AHRE: patients with AHRE (+) and patients without AHRE (-). Thereafter, patients baseline characteristics and scoring systems were analyzed for prediction of AHRE. The distribution of patients' baseline characteristics and scoring systems according to presence of AHRE was evaluated. Furthermore, ROC curve analyses of the stroke risk scoring systems have been investigated in terms of predicting the development of AHREs. ATRIA, which predicted AHRE with a specificity of 92% and sensitivity of 37.5% for ATRIA values of>6, performed better than other scoring systems in predicting AHRE (AUC: 0.700, 0.626-0.767 95% confidence interval (CI), p=.004) CONCLUSION: AHRE is common in patients with a CIED. In this context, several risk scoring systems have been used to predict the development of AHRE in patients with a CIED. This study's findings revealed that The ATRIA stroke risk scoring system performed better than other commonly used risk scoring systems in predicting AHRE.