Shorter Atrial Fibrillation Duration Research Articles

Atrial fibrillation detection on implantable loop recorders in embolic stroke of undetermined source

Abstract Introduction Embolic stroke of undetermined source (ESUS) represents 17% of all ischaemic strokes, and has a 5% annual stroke recurrence risk. Recent large randomised control trials failed to demonstrate a benefit of empirical anticoagulation for all ESUS patients, with sub-analyses supporting the need for a tailored approach to those patients at greatest risk of atrial fibrillation (AF) development. Understanding how the increased incidence of ILR-detected AF in the ESUS cohort, compares with ILR-detected AF in other cohorts is an essential step in understanding the significance of this finding. Purpose To compare the incidence of ILR-detected AF following ESUS against patients undergoing ILR implantation for non-stroke indications for example syncope and palpitations. Methods We retrospectively studied all patients without known AF who were referred to our institution for ILR implantation following ESUS, syncope or palpitations from 2009 to 2019. The primary endpoint was any detection of AF or atrial flutter (AFL) by ILR. Kaplan-Meier and multivariable Cox-regression analyses were utilised to account for time-to-event. Results A total of 750 patients were included and followed up for a mean of 731 days (SD 443). An ILR was implanted following ESUS in 323 patients and for another reason in 427 patients (figure 1). The incidence of AF was significantly higher among patients with ESUS compared to the non-ESUS group; 48.6% versus 13.8% (for any duration of AF) and 32.2% versus 12.4% (for AF lasting > 30 seconds) both p <0.001. Kaplan-Meier analysis (figure 2), showed significantly higher incidence of AF for ESUS for any duration of AF. This was driven predominantly by AF duration <6 minutes and between 5.5 hours and 24 hours. Importantly, in a multivariable Cox regression analysis, ESUS independently conferred an almost 5-fold increase in the hazard for any duration of AF (Hazard Ratio 4.948, 95% confidence interval 3.587 – 6.825, p<0.001). Conclusion The incidence of AF is significantly higher amongst ESUS versus non-ESUS patients monitored constantly by an ILR. A high number of ESUS survivors have short duration AF episodes. Further work is needed to determine the optimal treatment strategy of these AF episodes in ESUS considering AF duration and overall burden.

The incidence of atrial fibrillation detected by implantable loop recorders: a comparison between patients with and without embolic stroke of undetermined source.

Stroke is the most debilitating outcome of atrial fibrillation (AF). The use of implantable loop recorders increases the detection of AF episodes among patients with embolic stroke of undetermined source. The significance of device-detected AF, or subclinical AF, is unknown. This study aimed to compare the incidence of AF detected by implantable loop recorder in patients with and without embolic stroke of undetermined source. We retrospectively studied all patients without known AF who were referred to our institution for implantable loop recorder implantation following embolic stroke of undetermined source, syncope, or palpitations from March 2009 to November 2019. The primary endpoint was any detection of AF or atrial flutter by implantable loop recorder. Seven hundred and fifty patients were included and followed up for a mean duration of 731 days (SD 443). An implantable loop recorder was implanted following embolic stroke of undetermined source in 323 and for assessment of syncope, palpitations, or another reason in 427 patients. The incidence of AF was significantly (P < 0.001) higher among patients with embolic stroke of undetermined source compared with the non-embolic stroke of undetermined source group; 48.6% vs. 13.8% (for any duration of AF) and 32.2% vs. 12.4% (for AF lasting ≥30 s) both P < 0.001. Kaplan-Meier analysis showed significantly higher incidence of AF for incremental durations of AF up to >5.5 h, but not >24 h. This was driven by longest AF durations of <6 min and between 5.5 h and 24 h, suggesting a bimodal distribution. In a multivariable Cox regression analysis, embolic stroke of undetermined source independently conferred an almost 5-fold increase in the hazard for any duration of AF. The incidence of AF is significantly higher amongst embolic stroke of undetermined source vs. non-embolic stroke of undetermined source patients monitored constantly by an implantable loop recorder. A high number of embolic stroke of undetermined source survivors have short-duration AF episodes. Further work is needed to determine the optimal treatment strategy of these AF episodes in embolic stroke of undetermined source.

Clinical effect of vein of Marshall ethanol infusion on mitral isthmus ablation.

This study aimed to investigate the effect of Marshall ethanol infusion (VOM-Et) in the vein on mitral isthmus (MI) ablation. Patients with persistent atrial fibrillation (AF) were grouped into vein of VOM-Et combined with radiofrequency (RF) ablation (VOM-Et-RF) and RF groups. The primary outcome was MI block immediate block rate after surgery. Stratified analysis was also performed for factors affecting the outcome measures. A total of 118 consecutive patients underwent AF ablation at Taizhou Hospital of Zhejiang Province from January 2018 to December 2021. Successful bidirectional perimitral block was achieved in 96% of patients in VOM-Et-RF (69 of 72) and in 76% of patients in the RF group (35 of 46) (P < 0.01). In the subgroup analysis, male sex, elder than 60 years, Left atrial diameter <55 mm, and AF duration <3 years were associated with the benefits of VOM-Et in AF Patients. The vein of Marshall ethanol infusion for catheter ablation can improve the MI block rate. Male sex, elder age, smaller Left atrial diameter and shorter AF duration may have significant benefits for VOM-Et.

Antiarrhythmic drugs for pharmacological cardioversion of atrial fibrillation and sex differences: Insights from the CANT II Study.

Data on sex differences in terms of action of antiarrhythmic agents (AADs) are limited. This study aimed to evaluate the clinical profile of patients with atrial fibrillation (AF), and efficacy and safety of AADs used for pharmacological cardioversion (PCV) of AF. This research was a sub-analysis of the retrospective multicenter Cardioversion with ANTazoline II (CANT) registry, which comprised 1365 patients with short-duration AF referred for urgent PCV with the use of AAD. Patients were categorized according to and compared in terms of clinical parameters and PCV outcomes. The primary endpoint was return of sinus rhythm within 12 hours after drug infusion, and the composite safety endpoint involved bradycardia <45 bpm, hypotension, syncope, or death. The sex distribution of patients qualified for PCV was even (men, n = 725; 53.1%). Females were older and more symptomatic and had higher CHA2DS2-VASc scores, higher prevalence of tachyarrhythmia, and higher use of chronic anticoagulation. The overall efficacy (71.4% vs. 70.1%; P = 0.59) and safety (5.2% vs. 4.6%; P = 0.60) of PCV was comparable in men and women. Amiodarone (68.3% vs. 65.9%; P = 0.66) and antazoline (77.1% vs. 80.0%; P = 0.19) had similar efficacy in men and women, but propafenone had a lower rate of rhythm conversion in men (64.7% vs. 79.3%; P = 0.046). None of the assessed AADs differed in terms of safety profile in both sexes. Female patients with AF have different clinical profiles but similar efficacy and safety of AADs as compared to male participants. Propafenone has significantly lower efficacy in men, which requires further investigation.

Impact of high-power short-duration atrial fibrillation ablation technique on the incidence of silent cerebral embolism: a prospective randomized controlled study

BackgroundHigh-power short-duration (HPSD) ablation strategy has emerged as a popular approach for treating atrial fibrillation (AF), with shorter ablation time. The utilized Smart Touch Surround Flow (STSF) catheter, with 56 holes around the electrode, lowers electrode-tissue temperature and thrombus risk. Thus, we conducted this prospective, randomized study to investigate if the HPSD strategy with STSF catheter in AF ablation procedures reduces the silent cerebral embolism (SCE) risk compared to the conventional approach with the Smart Touch (ST) catheter.MethodsFrom June 2020 to September 2021, 100 AF patients were randomized 1:1 to the HPSD group using the STSF catheter (power set at 50 W) or the conventional group using the ST catheter (power set at 30 to 35 W). Pulmonary vein isolation was performed in all patients, with additional lesions at operator’s discretion. High-resolution cerebral diffusion-weighted magnetic resonance imaging (hDWI) with slice thickness of 1 mm was performed before and 24–72 h after ablation. The incidence of new periprocedural SCE was defined as the primary outcome. Cognitive performance was assessed using the Montreal Cognitive Assessment (MoCA) test.ResultsAll enrolled AF patients (median age 63, 60% male, 59% paroxysmal AF) underwent successful ablation. Post-procedural hDWI identified 106 lesions in 42 enrolled patients (42%), with 55 lesions in 22 patients (44%) in the HPSD group and 51 lesions in 20 patients (40%) in the conventional group (p = 0.685). No significant differences were observed between two groups regarding the average number of lesions (p = 0.751), maximum lesion diameter (p = 0.405), and total lesion volume per patient (p = 0.669). Persistent AF and CHA2DS2-VASc score were identified as SCE determinants during AF ablation procedure by multivariable regression analysis. No significant differences in MoCA scores were observed between patients with SCE and those without, both immediately post-procedure (p = 0.572) and at the 3-month follow-up (p = 0.743).ConclusionsInvolving a small sample size of 100 AF patients, this study reveals a similar incidence of SCE in AF ablation procedures, comparing the HPSD strategy using the STSF catheter to the conventional approach with the ST catheter.Trial registrationClinicaltrials.gov: NCT04408716.Graphical AF = Atrial fibrillation, DWI = Diffusion-weighted magnetic resonance imaging, HPSD = High-power short-duration, ST = Smart Touch, STSF = Smart Touch Surround Flow.

Efficacy and safety of antiarrhythmic drugs for pharmacological cardioversion of atrial fibrillation depending on gender: a subanalysis of CANT II Study

Abstract Background/introduction The data on gender differences concerning antiarrhythmic drugs (AAD) applied in atrial fibrillation (AF) patients is scarce. Purpose The aim of the study was to evaluate gender differences in terms of clinical profile of AF patients, and efficacy and safety of AAD used for pharmacological cardioversion (PCV) of AF. Methods This research was a sub-analysis of retrospective multicenter Cardioversion with ANTazoline II (CANT) registry, which comprised 1365 patients with short-duration AF referred for urgent PCV with the use of AAD. Patients were categorized in terms of gender and compared in terms of clinical parameters and outcome of PCV. The primary endpoint was return of sinus rhythm within 12 hours after drug infusion and the composite safety endpoint involved bradycardia &amp;lt;45 bpm, hypotension, syncope or death. Results The majority of patients qualified for PCV were men (n=725, 53.1%). Females were older and more symptomatic, had higher CHA2DS2-VASc score, greater prevalence of tachyarrhythmia and higher utilization of chronic anticoagulation. The overall efficacy (71.4% vs. 70.1%,P=0.588) and safety (5.2% vs. 4.6%,P=0.603) of PCV was comparable in men and women. Amiodarone (68.3% vs. 65.9%, P=0.664) and antazoline (77.1% vs. 80.0%, P=0.19) had similar efficacy in men and women, but propafenone had lower rate of rhythm conversion in men (64.7% vs. 79.3%, P=0.046; Figure). None of the assessed AAD differed in terms of safety profile in both genders. Logistic regression showed that, among other predictors, in women the use of amiodarone vs. other AAD (odds ratio [OR] 0.569, P=0.033), while in men administration of a amiodarone (OR 0.379, P=0.001) or propafenone (OR 0.331, P=0.002) vs. other AAD were associated with lower chance of successful rhythm conversion. Conclusions Female patients with AF share different clinical profile and similar efficacy and safety of AAD used for PCV as compared to male participants. Propafenone has significantly lower efficacy in men, which requires further prospective investigation.

Revisiting pulmonary vein stenosis after high-power short-duration radiofrequency ablation in patients with atrial fibrillation

Abstract Background High-power short-duration atrial fibrillation catheter ablation (HPSD-AFCA) of pulmonary vein (PV) isolation reduces the procedure time without a difference in the efficacy as compared to conventional power AFCA (ConvP-AFCA). PV stenosis (PVS) after AFCA is a rare complication. Purpose We compared the frequency of symptomatic PVS as a long-term complication between the ConvP-AFCA and HPSD-AFCA groups. Methods We included 3,851 patients undergoing AFCA between 2009 and 2022 prospectively. We evaluated the characteristics of patients diagnosed with clinically symptomatic PVS, ascertained using computed tomography during the follow-up period. The risk of PVS was compared between the ConvP-AFCA and HPSD-AFCA groups using propensity overlap weighting. Results Symptomatic PVS was diagnosed in 14 (0.4%) patients at a mean of 342.9 days after the procedure. After overlap weighting, PVS was significantly more frequent in the HPSD-AFCA group (incidence: HPSD-AFCA, 0.8% vs. ConvP-AFCA, 0.2%; weighted hazard ratio [HR] 6.27, 95% confidence interval [CI] 2.15-18.28; P&amp;lt;0.001). In the multivariable Cox regression analyses, repeat AFCA procedures (HR 3.52, 95% CI 1.18-10.55; P=0.024) and paroxysmal AF (HR 8.29, 95% CI 1.08-63.82; P=0.042) were also independently associated with PVS after AFCA. Among the PVs of patients with PVS, stenotic PVs had shorter antral diameters and a smaller cross-sectional area than non-stenotic PVs on preprocedural computed tomographic evaluations. Conclusion HPSD-AFCA, compared to ConvP-AFCA, was associated with a 6-fold increased risk of symptomatic PVS. Caution is required, especially in patients with plans for a repeated AFCA, paroxysmal AF, or small PV antrum.

Incidence and predictors of stroke and silent cerebral embolism following very high-power short-duration atrial fibrillation ablation.

Cerebral thrombo-embolism is a dreaded complication of pulmonary vein isolation (PVI) for atrial fibrillation; its surrogate, silent cerebral embolism (SCE) can be detected by diffusion-weighted brain magnetic resonance imaging (bMRI). Initial investigations have raised a concern that very high-power, short-duration (vHPSD; 90 W/4 s) temperature-controlled PVI with the QDOT Micro catheter may be associated with a higher incidence of SCE compared with low-power long-duration ablation. We aimed to assess the incidence of procedural complications of vHPSD PVI with an emphasis on cerebral safety. We enrolled 328 consecutive patients undergoing their PVI procedure using vHPSD. A subgroup of 61 consecutive patients underwent diffusion-weighted bMRI within 24 h of the procedure, and incidence and predictors of SCE were studied. The mean procedure time and left atrial dwell time for the overall cohort were 69.6 ± 24.1 and 46.5 ± 21.5 min, respectively. First-pass isolation was achieved in 82%. No stroke or transient ischaemic attack occurred. Silent cerebral embolism was identified in 5 of 61 patients (8.2%). Silent cerebral embolism following procedures was significantly associated with lower baseline generator impedance (105.8 vs. 112.6 Ω, P < 0.0001) and with intermittent loss of catheter-tissue contact during ablation (14.1% vs. 6.1%, P < 0.0001). Very high-power, short-duration PVI is a safe technique with an excellent acute success rate. Silent cerebral embolism incidence in our cohort was below the previously reported range, with no clinically overt cerebral complications. Lower baseline generator impedance and loss of contact during ablation may contribute to a higher risk of SCEs.

5-Methoxytryptophan alleviates atrial structural remodeling in ibrutinib-associated atrial fibrillation

BackgroundIbrutinib is an effective and well-tolerated treatment for B-cell lymphomas but is associated with an increased risk of atrial fibrillation (AF) by altering the structure of the atrium. 5-Methoxytryptophan (5-MTP) inhibits inflammatory and fibrotic processes. This study aimed to determine the effects and mechanisms of 5-MTP on the underlying mechanisms of AF caused by ibrutinib. MethodsThe effect of 5-MTP on ibrutinib-related AF was investigated in male Sprague Dawley rats using echocardiographic, electrophysiological, immunofluorescent, Masson staining, and molecular analyses. RusultsThe ibrutinib+5-MTP group showed (1) a lower incidence and shorter duration of AF and accelerated atrial conduction; (2) a decreased left atrial mass and left atrial diameter; (3) decreased myocardial fibrosis in the left atrium; (4) lower atrial inflammation; (5) increased sarcoplasmic reticulum Ca2+-ATPase 2a protein expression, decreased phosphorylation of phospholamban at Thr17, and decreased sodium/calcium exchanger 1 protein expression and phosphorylation of ryanodine receptor 2 at S2814; and (6) decreased phosphorylation of CaMKII expression. 5-MTP treatment markedly activated the PI3K-Akt signaling. Inhibiting PI3K-Akt signaling significantly reversed the protective effect of 5-MTP on ibrutinib-related AF. ConclusionsThese findings suggest that 5-MTP administration decreases the vulnerability of ibrutinib-related AF mainly caused by ameliorated maladaptive left atrial remodeling and dysregulation of calcium handling proteins. Mechanistically, 5-MTP treatment markedly enhanced the activation of cardiac PI3K-Akt signaling.

Comparison between weight-adjusted, high-frequency, low-tidal-volume ventilation and atrial pacing with normal ventilation in high-power, short-duration atrial fibrillation ablation: Results of a pilot study.

Better contact force (CF) and catheter stability (CS) during atrial fibrillation (AF) ablation are associated with higher success rate. Changes in CF and CS are observed during respiratory movements and cardiac contraction. Previous studies have suggested that rapid atrial pacing (RAP) and high-frequency, low-tidal-volume ventilation (HFLTV) independently or in combination improve CS and CF and quality of lesions. Data from a body weight-adjusted HFLTV strategy associated with RAP in AF high-power, short-duration (HPSD) ablation are still lacking. This study aimed to compare the results of HPSD AF ablation using simultaneous weight-adjusted HFLTV and RAP and standard ventilation (SV) protocol. This was a prospective, nonrandomized study with 136 patients undergoing de novo ablation were divided into 2 groups: 70 in RAP (100 ppm) + HFLTV with 4 mL/kg of tidal volume and 25 breaths/min (group A) and 66 patients with SV in intrinsic sinus rhythm (group B). The ablation used 50 W, CF of 5 to 10 g and 10 to 20 g, and 40 mL/min flow rate on the posterior and anterior left atrial walls, respectively. There were no procedure-related complications. In group A, left atrial and total ablation times were 53.5 ± 8.3 minutes and 67.4 ± 10.1 minutes, respectively. Radiofrequency time was 19.7 ± 5.7 minutes, radioscopy time was 3.4 ± 1.8 minutes, 62 (88.6%) patients had first-pass isolation, 23 (33.3%) patients had elevation of luminal esophageal temperature, and 7 (10%) patients had recurrence. In group B, left atrial time was 56.7 ± 10.8 minutes, total ablation time was 72.4 ± 11.5 minutes, radiofrequency time was 22.4 ± 6.2 minutes, radioscopy time was 3.6 ± 3 minutes, 58 (87.9%) patients had first-pass isolation, and 20 (30.3%) patients had luminal esophageal temperature elevation. Weight-adjusted HFLTV with RAP in comparison with SV and intrinsic sinus rhythm in HPSD ablation is safe with no CO2 retention. The approach produced significantly reduced radiofrequency, left atrial, and total ablation times and better CF and local impedance drop indexes.

Study of ECG-derived atrial fibrillatory rate for prediction of the outcome of cardioversion of short duration atrial fibrillation (CASAF)

AimsThe present study aimed at testing the hypothesis that atrial fibrillatory rate (AFR) is predictive of sinus rhythm maintenance after electrical cardioversion. Methods and resultsThe study comprised 32 patients admitted for cardioversion of atrial fibrillation of short duration (mean duration 3.8 ± 7.7 days). AFR was estimated using frequency power spectrum analysis of QRST-cancelled ECG.At six-weeks follow-up 22% of the patients had relapsed to AF. The pre-cardioversion mean AFR of those was 332 ± 64 fpm compared to 378 ± 59 fpm among patients maintaining sinus rhythm (p = 0.12). ConclusionAFR was not predictive of sinus rhythm maintenance in patients of short duration AF undergoing cardioversion. This is in stark contrast with the earlier reported findings. Clinical trial registrationNCT02112318 (http://www.clinicaltrials.gov).

Acute oesophageal safety and long-term follow-up of AI-guided high-power short-duration with 50 W for atrial fibrillation ablation.

Pulmonary vein isolation using radiofrequency ablation is an effective treatment option for patients with symptomatic atrial fibrillation (AF). Application of high power over a short period of time (HPSD) is reported to create more efficient lesions and may prevent collateral thermal oesophageal injury. This study aims to compare efficacy and safety of two different HPSD ablation approaches using different ablation index settings. Consecutive patients undergoing AF ablation with HPSD (50 W; ablation index-guided) using the ThermoCool SmartTouch SF catheter were included. Patients were grouped by ablation protocol: ablation with target ablation index (AI) of 400 on the anterior left atrial wall vs. 300 at the posterior left atrial wall (AI 400/300) or AI 450/350 was performed upon the operator's preference and compared. Peri-procedural parameters and complications were recorded, and incidences of endoscopically detected thermal oesophageal lesions (EDEL) analysed. Recurrence rates after a mean follow-up of 25 ± 7 months and reconnection patterns in patients undergoing redo procedures were investigated. A total of 795 patients (67 ± 10 years; 58% male; 48% paroxysmal AF) underwent a first AF ablation with HPSD (211 in group AI 400/300 and 584 in group 450/350). Median procedure time was 82.9 ± 24.6 min with longer ablation times in patients with target AI 400/300 due to higher intraprocedural reconnection rates, increased box lesions, and additional right atrial isthmus ablations. EDEL rates among target AI 400/300 procedures were significantly lower (3% vs. 7%; P = 0.019). Correspondingly, AI 450/350 was the strongest independent predictor of post-ablation EDEL (OR 4.799, CI 1.427-16.138, P = 0.011). Twelve-month (76% vs. 76%; P = 0.892) and long-term ablation single procedure success (68% vs. 71%; log-rank P = 0.452) after a mean of 25 ± 7 months were comparable among both target AI groups; however, long-term success was significantly higher for paroxysmal AF compared to persistent AF (12 months: 80% vs. 72%; P = 0.010; end of follow-up: 76% vs. 65%; log-rank P = 0.001). One hundred three patients (16%) underwent a redo procedure during follow-up documented comparable pulmonary vein (PV) reconnection among groups. Multivariate predictors of AF recurrence were age, left atrium (LA) size, persistent AF, and extra-PV ablation targets. High-power short-duration AF ablation with target AI of 400 for non-posterior wall and 300 for posterior wall lesions resulted in comparable long-term results compared to higher AI (450/350) ablations with significantly lower risk for thermal oesophageal lesions. Older age, larger LA size, persistent AF, and extra-PV ablation targets were identified in a multivariate analysis as independent risk factors for recurrences of atrial arrhythmias.

Very long term outcomes of atrial fibrillation ablation

Little is known about the very long term durability of atrial fibrillation (AF) ablation. The purpose of this study was to evaluate very long term AF ablation outcomes. We followed 5200 patients undergoing 7145 ablation procedures. We evaluated outcomes after single and multiple ablation procedures for paroxysmal (PAF; 33.6%), persistent (PeAF; 56.4%), and long-standing (LsAF; 9.9%) AF. We compared 3 ablation eras by initial ablation catheter: early (101 patients) using solid big tip (SBT) catheters (October 2003 to December 2005), intermediate (2143 patients) using open irrigated tip (OIT) catheters (December 2005 to August 2016), and contemporary (2956 patients) using contact force (CF) catheters (March 2014 to December 2021). AF freedom at 5, 10, and 15 years was as follows: initial ablation: PAF 67.8%, 56.3%, 47.6%; PeAF 46.6%, 35.6%, 26.5%; and LsAF 30.4%, 18.0%, 3.4%; final ablation: PAF 80.3%, 72.6%, 62.5%; PeAF 60.1%, 50.2%, 42.5%; and LsAF 43.4%, 32.0%, 20.6%. For PAF and PeAF, CF ablation procedures were better than OIT ablation procedures (P < .0001) and both were better than SBT ablation procedures (P < .001). LsAF had no outcome improvement over the eras. The 8-year success rate after final ablation for CF, OIT, and SBT catheter eras was as follows: PAF 79.1%, 71.8%, 60.0%; PeAF 55.9%, 50.7%, 38.0%; and LsAF 42.7%, 36.2%, 31.8%. Highest AF recurrence was in the first 2 years, with a 2- to 15-year recurrence of 2%/yr. Success predictors after initial and final ablation procedures were younger age, smaller left atrium, shorter AF duration, male sex, less persistent AF, lower CHA2DS2-VASc score, fewer drugs failed, and more recent catheter era. After year 2, there is 2%/yr recurrence rate for all AF types. Ablation success is best in the CF catheter era, intermediate in the OIT era, and worst in the SBT era. Over the ablation eras, outcomes improved for PAF and PeAF but not for LsAF. We should follow patients indefinitely after ablation. We need an understanding of how to better ablate more persistent AF.

Effect of angiotensin receptor-neprilysin inhibitor on atrial electrical instability in atrial fibrillation.

Around 33.5 million patients suffered from atrial fibrillation (AF), causing complications and increasing mortality and disability rate. Upstream treatment for AF is getting more popular in clinical practice in recent years. The angiotensin receptor-neprilysin inhibitor (ARNI) is one of the potential treatment options. Our study aimed to investigate the effect of ARNI on atrial electrical instability and structural remodeling in AF. Our research consisted of two parts - a retrospective real-world clinical study and an animal experiment on calmness to verify the retrospective founding. In the retrospective study, we reviewed all patients (n = 110) who had undergone the first AF ablation from 1 August 2018 to 1 March 2022. Patients with ARNI (n = 36) or angiotensin II receptor antagonist (ARB) (n = 35) treatment were enrolled. Their clinical data, ultrasound cardiogram (UCG) and Holter parameters were collected before radiofrequency catheter ablation (RFCA) as baseline and at 24-week follow-up. Univariate and multivariate logistic regression analysis were performed. In the animal experiment, we established an AF model (n = 18) on canines by rapid atrial pacing. After the successful procedure of pacing, all the 15 alive beagles were equally and randomly assigned to three groups (n = 5 each): Control group, ARB group, and ARNI group. UCG was performed before the pacing as baseline. Physiological biopsy, UCG, and electrophysiological study (EPS) were performed at 8-week. Clinical data showed that the atrial arrhythmia rate at 24-week was significantly lower in ARNI group compared to ARB group (P < 0.01), and ARNI was independently associated with a lower atrial arrhythmia rate (P < 0.05) at 24-week in multivariate regression logistic analysis. In the animal experiment, ARNI group had a higher atrial electrical stability score and a shorter AF duration in the EPS compared to Control and ARB group (P < 0.05). In the left atrium voltage mapping, ARNI group showed less low voltage and disordered zone compared to Control and ARB group. Compared to Control group, right atrium diameter (RAD), left ventricle end-diastolic volume index (LVEDVI), E/A, and E/E' were lower in ARNI group (P < 0.05) at the 8-weeks follow-up, while left atrium ejection fraction (LAEF) and left ventricle ejection fraction (LVEF) were higher (P < 0.01). Compared to ARB group, LVEF was higher in ARNI group at the 8-week follow-up (P < 0.05). ARB and ARNI group had a lower ratio of fibrotic lesions in the left atrium tissues compared to Control group (P < 0.01), but no difference was found between the ARB and the ARNI group. ARNI could reduce atrial electrical instability in AF in comparison with ARB in both retrospective study and animal experiment.

Incidence and clinical impact of tachyarrhythmic events following transcatheter aortic valve replacement: A review.

Transcatheter aortic valve replacement (TAVR) is well established for treating severe symptomatic aortic stenosis. Whereas broad information on the epidemiology, clinical implications, and management of bradyarrhythmias after TAVR is available, data about tachyarrhythmic events remain scarce. Despite the progressively lower risk profile of TAVR patients and the improvement in device characteristics and operator skills, approximately 10% of patients develop new-onset atrial fibrillation (NOAF) after TAVR. The proportion of patients in whom NOAF actually corresponds to previously undiagnosed silent atrial fibrillation (AF) has not been properly determined. The transapical approach, the need for pre- or post- balloon dilation, and the presence of periprocedural complications have been associated with a higher risk of NOAF. Older age, left atrial volume, or worse functional class are patient-derived risk factors shared with preprocedural AF. NOAF after TAVR has been associated with poorer survival and a higher incidence of cerebrovascular events. However, patient management differs markedly among different centers, especially with regard to anticoagulation in patients with short-duration AF episodes detected in the periprocedural setting and in cases of silent NOAF detected during continuous electrocardiographic (ECG) monitoring. Evidence about ventricular arrhythmias is even more scarce than for AF. Some case reports of sudden cardiac death after TAVR in patients with a pacemaker have identified ventricular tachycardia or ventricular fibrillation in device interrogation. TAVR has been shown to reduce the arrhythmic burden, but a significant proportion of patients (16%) present with complex premature ventricular complex arrhythmias within the year after TAVR. Whether these events are related to poorer outcomes is unknown. Continuous ECG monitoring after TAVR may help describe the frequency, risk factors, and prognostic implications of tachyarrhythmias in this population.

Sex differences in presentation of atrial fibrillation: Findings from 30-day ambulatory monitoring in real-world practice

BackgroundWomen are less likely to receive oral anticoagulation or ablation for treatment of atrial fibrillation (AF). Identification of sex differences in arrhythmia characteristics and symptoms may lead to a better understanding of potential reasons for these differences. ObjectivesTo determine sex differences in AF with respect to heart rate, duration, burden, and symptoms in patients undergoing mobile cardiac telemetry (MCT) monitoring. MethodsAll patients who registered for ≤30-day MCT using PocketECG (MediLynx) in the USA in 2017 were included (n = 27,512, 58 % women). PocketECG records and transmits a three-lead ambulatory electrocardiogram (ECG) with real-time beat-to-beat analysis. Sex-related differences were analyzed with Chi2 and Spearmans rho. ResultsFewer women than men were diagnosed with AF lasting ≥30s (13.7 % versus [vs] 19.0 %, p < 0.001). AF burden was lower in women in all age groups <90 years (all p < 0.01). Women were older at the time of AF diagnosis (median 76 vs 73 years, p < 0.001), had faster heart rate during AF (mean: 104.7 ± 26.0 vs 96.7 ± 26.7 bpm, p < 0.001), and shorter AF duration (mean: 96.2 ± 176.0 vs 121.6 ± 189.9 min, p < 0.001). There was a non-significant trend toward more symptoms (such as dizziness, racing heart, fatigue, or palpitations) during AF in women compared to men (46.5 % vs 43.7 %, p = 0.062). ConclusionsAF was less prevalent and occurred at lower burdens in women than men in each age strata. Despite faster heart rates in AF in women, there were no significant sex differences in reported symptoms during AF. Sex differences in therapy cannot be explained by differences in symptoms or rates in AF. Condensed abstractReal-world data on sex differences in AF using a 30-day MCT monitoring device remain scarce. We aim to determine the sex differences in AF with respect to prevalence, burden, heart rate, and symptom in patients undergoing ≤30-day MCT monitoring. Our data analysis suggests that fewer women than men had AF, women were older at diagnosis of AF, and women with AF had higher mean heart rate, shorter mean AF duration, and lower mean AF burden than men. Further studies are needed to examine reasons for sex differences, specifically in relation to AF therapy and its impact on clinical outcomes.

Evaluation of atrial contractility and remodeling after the Maze-3 procedure with combined heart interventions

Highlights. The most important goal of atrial fibrillation surgical treatment is to eliminate the arrhythmia in order to restore atrial contractility and improve their transport function. Our study showed positive dynamics of atrial contractility and remodeling after the maze-3 procedure against the background of a regular heart rhythm restoration. The study of sinus rhythm predictors maintenance and recovery of atrial transport function will help to make patient selection more personified.Aim. Evaluation of atrial contractility and remodeling after the maze-3 procedure with combined interventions on the heart.Methods. The analysis of 217 combined surgical interventions was carried out, where a maze-3 was used to treat atrial fibrillation (AF). The operations were performed in our center from 2012 to 2016. Key points of the study: rhythm after surgery and echocardiographic control in the long-term follow-up in order to determine the dynamics of atrial contractility and volumes. The average follow-up period was 47 (1–100) months. 40 (18.4%) patients had paroxysmal, 38 (17.5%) persistent, 139 (64.1%) long-term persistent AF. The mean AF duration before surgery was 27.4 months (1–200 months). The indications for the maze-3 procedure were: ineffectiveness of antiarrhythmic therapy, the need to perform combined cardiac procedures. We used standard statistical research methods with one – and multivariate logistic regression.Results. In the long-term follow-up, sinus rhythm (SR) persists in 79% of patients. In the long-term follow-up, in this group of patients, the left atrial contractility was restored from 76% to 91%, while the biatrial contractility increased from 82 to 96%. Shorter AF duration before surgery was a positive predictor of SR recovery and atrial contractility (p = 0.005), while pulmonary artery pressure and patient age negatively affected these indicators (p = 0.041 and p = 0.038, respectively). The presence of SR early after surgery was not a significant predictor of AF freedom. At the same time, according to the long-term observations, patients maintaining a regular atrial heart rate had positive indicators of atrial systolic function restoration and a positive dynamics of a decrease in atrial volumes.Conclusion. SR and restoration of left atrial contractility are two interrelated goals of the maze procedure. The negative factors associated with the failure of surgical treatment of AF are increased pressure in the pulmonary artery, long-term AF before surgery, and the age of patients.

Artificially Created Reentry Circuit by Laser Irradiation Causes Atrial Tachycardia to Persist in Murine Atria.

There is a gradual progression from paroxysmal to persistent atrial fibrillation (AF) in humans. To elucidate the mechanism involved, the creation of an artificial atrial substrate to persist AF in mice was attempted.Methods and Results:This study used wild type (WT) mice, but it is difficult to induce AF in them. A novel antegrade perfusion method from the left ventricle (LV) to enlarge both atria for artificial atrial modification was proposed in this study. Short duration AF was induced by burst pacing under this method. Optical mapping analysis revealed non-sustained focal type and meandering spiral reentrants after short duration AF. A tiny artificial substrate (~1.2 mm in diameter) was added in by laser irradiation to create a critical atrial arrhythmogenic substrate. Burst pacing was performed in a non-laser group (n=8), a circular-shape laser group (n=8), and a wedge-shaped dent laser group (n=8). We defined AF and atrial tachycardia (AT) as atrial arrhythmia (AA). Long-lasting AA was defined as lasting for ≥30 min. Long-lasting AA was observed in 0/8, 0/8, and 6/8 (75%) mice in each group. Optical mapping analysis revealed that the mechanism was AT with a stationary rotor around the irradiated margin. Regrettably, this study failed to reproduce persistent AF, but succeeded in creating an arrhythmic substrate that causes sustained AT in WT mice.

Systematic review of the safety and efficacy of antazoline in the treatment of atrial fibrillation

Context: In the emergency department, patients with recent-onset atrial fibrillation are typically managed with intravenous antiarrhythmic agents. However, the currently used agents have a low efficacy and safety profile. Antazoline is an antihistaminic agent that has been shown to have a strong antiarrhythmic effect when administered intravenously, facilitating rapid conversion to normal sinus rhythm. Aims: To systematically review the literature on the safety and efficacy of antazoline in the treatment of recent-onset short-duration atrial fibrillation and to compare the clinical efficacy of antazoline to that of other antiarrhythmic agents listed in clinical guidelines. Methods: The study was written in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. A comprehensive search of databases (PubMed, Scopus, ScienceDirect, Web of Sciences, Google Scholar, Clinical trial.gov) for relevant studies in English from inception to 2021 using keywords involving “antazoline” AND other terms such as “antiarrhythmic”, “atrial fibrillation”, and “arrhythmia”. Results: Of the 478 studies identified, 446 were screened, and 7 were included, one of which was a randomized control trial, and the others were observational studies. The majority of studies indicated that antazoline resulted in rapid cardioversion to sinus rhythm. When compared to other pharmacological cardioversion options, antazoline achieved higher cardioversion rates than amiodarone or propafenone and was generally a safer option. Conclusions: Antazoline appears to be an effective pharmacological agent for the rapid cardioversion of short-term atrial fibrillation. More randomized clinical trials, however, should be conducted to strengthen the evidence.

Cryoablation: safety of same day discharge

Abstract Introduction Discharge after overnight hospital stay is standard procedure in patients submitted to elective atrial fibrillation (AF) ablation. Taking into consideration the low rate of cryoablation procedure complications could the same day discharge be an option? Purpose To assess the safety of same day discharge of patients submitted to AF cryoablation. Methods Single-center retrospective study of consecutive patients admitted to elective AF cryoablation in a tertiary center between February 2017 and November 2020. Patients were divided into two groups: same day discharge and next day discharge. Only patients submitted to ablation until 4 p.m. were included. Complication rates were obtained up to six months after the procedure. Complications were defined as death, pericardial tamponade, hematoma requiring evaluation and/or intervention, major bleeding requiring transfusion, hospital admission related to the procedure. Results One hundred fifty-four patients were included, with a mean age of 61±10.9 years, 66.2% were males, 18.2% with diabetes, 65.6% with dyslipidemia, 77.9% with hypertension, 10.4% with chronic kidney disease KDIGO stage 3 or more. Median follow-up of 436 [178 – 729] days. Most of the patients had paroxysmal (73.4%) and persistent short duration AF (23.4%). Sixty-two patients (40.3%) were early discharged and there were no differences between the two groups regarding epidemiological and clinical characteristics (p=NS). A very low rate of complications in both groups was observed, occurring in 6.5% of patients with early discharge and in 8.7% of patients in overnight stay, without statistical significance between the two groups (p=0.61). The most frequent complications were local hematoma (5 patients, 2 in early discharged group), pericardial effusion (3 patients, all in overnight stay), femoral pseudo-aneurism (2 patients, 1 in each group) and arteriovenous fistula (1 patient in overnight stay group). The type of complications did not differ between the two groups (p=0.51). Two patients died during follow up, and this was unrelated to the procedure. In addition, no difference in success rate and arrhythmic recurrence was observed between the two groups (p=NS). Conclusion Our study suggests that it is safe to early discharge patients submitted to AF ablation, reducing the hospital stay length in selected patients. Larger studies are needed to confirm this data before routine implementation of this strategy. Funding Acknowledgement Type of funding sources: None.