Symptomatic Drug-refractory Atrial Fibrillation Research Articles

The Feasibility, Safety and Outcome of Very High-Power Short Duration Radiofrequency Ablation in Pulmonary Vein Isolation: A Real-World Observation Study.

Pulmonary vein isolation (PVI) ablation is the established gold standard therapy for patients with symptomatic drug refractory atrial fibrillation (AF). Advancements in radiofrequency (RF) ablation, have led to the development of the novel contact force-sensing temperature-controlled very high-power short-duration (vHPSD) RF ablation. This setting delivers 90 W for up to 4 seconds with a constant irrigation flow rate of 8 mL/min. The aim of this study was to compare procedural outcomes and safety with conventional radiofrequency ablation. An observational study was conducted with patients who underwent first time PVI ablation between August 2020 and January 2022. The cohort was divided into: (1) vHPSD ablation; (2) High-power short duration (HPSD) ablation; (3) THERMOCOOL SMARTTOUCH™ SF (STSF). The vHPSD ablation group was prospectively recruited while the HPSD and STSF group were retrospectively collected. Primary outcomes were procedural success, PVI duration, ablation duration and incidence of perioperative adverse events. Secondary outcomes were intraprocedural morphine and midazolam requirement. A total of 175 patients were included in the study with 100, 30 and 45 patients in the vHPSD, HPSD and STSF group, respectively. PVI was successfully attained in all vHPSD patients. vHPSD demonstrated significantly reduced time required for PVI and total energy application in comparison to the HPSD and STSF groups (67.7 29.7 vs. 92.9 25.7 vs. 93.6 29.1 min, p 0.0001; 9.87 4.16 vs. 33.9 7.49 vs. 36.0 10.5 min, p 0.0001, respectively). Intravenous morphine and midazolam requirement was lower in the vHPSD group compared to the HPSD and STSF groups (10.2 3.43 vs. 16.1 4.58 vs. 15.3 3.94 mg, p 0.0001; 4.04 3.24 vs. 8.63 5.22 vs. 8.58 4.72 mg, p 0.0001). One cardiac tamponade was observed in both the vHPSD and HPSD groups while the STSF group exhibited an embolic stoke and two pericardial effusions that did not require drainage. In this study, vHPSD demonstrated a comparable safety profile to the other treatment arms. Procedural duration and energy application time was substantially reduced along with sedation requirement notwithstanding the limitations of observational study design, these preliminary findings are promising with respect to periprocedural outcomes and safety of vHPSD however longitudinal outcomes will be essential to assessing the overall efficacy of this novel technology.

A Long Atrial Electromechanical Interval is Associated with Arrhythmic Recurrence after Catheter Ablation: How to Find What Has Been Lost.

Atrial fibrillation (AF) results in electrical and structural remodeling of the atria, which extent is known to be associated with a higher AF recurrence rate after catheter ablation (CA). Recently, a novel echocardiographic parameter derived from tissue Doppler imaging (TDI) [PA-TDI] has been introduced to assess the total atrial activation time, as a noninvasive surrogate of fibrosis and remodeling. The aim of the study is to investigate the role of PA-TDI interval as a predictor of AF ablation efficacy. We retrospectively included patients with paroxysmal symptomatic drug-refractory AF referred to our institution for CA procedure, who presented sinus rhythm at admission. A complete transthoracic echocardiogram was performed before the ablation procedure, including the assessment of PA-TDI interval. From January 2015 to April 2018, 128 patients (mean age: 61.86 ± 9.08 years, 68% male, body surface area: 1.97 ± 0.21 mq, body mass index: 26.98 ± 3.86 kg/mq, and ejection fraction: 59% ±6.06%) with symptomatic drug-refractory AF who received radiofrequency CA were enrolled. During the follow-up of 15.80 ± 6.7 months, 30 patients (23%) developed AF recurrence out of the blanking period. Compared with those without recurrence (group 1), patients with recurrence (group 2) had a larger left atrium (LA) size (Group 1 vs. Group 2: mean LA area: 22.2 ± 4.6 cmq vs. 25 ± 6.6 cmq, P = 0.015; mean indexed LA volume: 35 ± 10 mL/mq vs. 40 ± 12 mL/mq, P = 0.04) and longer PA-TDI interval (Group 1 vs. Group 2: 162 ± 33 ms vs. 133 ± 26 ms, P < 0.0001). A cutoff of PA-TDI > 150 ms identified patients with recurrence after ablation with a sensibility of 82% and specificity of 83% (area under the curve 0.879). The total activation time assessed by PA-TDI is an independent predictor of AF recurrence and can be used to predict the efficacy of transcatheter ablation.

Association between left atrial wall thickness and residual potential after first-pass pulmonary vein isolation using very high-power short-duration ablation in patients with atrial fibrillation

Abstract Background In this study, we evaluated efficacy, efficiency, and safety of pulmonary vein isolation (PVI) applying vHPSD ablation strategy in patients with atrial fibrillation (AF) and explored the association between left atrial wall thickness (LAWT) and the residual potential after first-pass PVI. Methods Between April 2, 2023 and October 6, 2023, drug refractory symptomatic AF patients who underwent AF ablation using vHPSD ablation strategy with QDOT MICRO catheter were prospectively enrolled. All patients took cardiac computed tomography (CT) a day before procedure. Using CT image, LAWT map was created. PV segments were categorized into prespecified 14 segments, and LAWT of each segment, segments with residual potential (RP) after first-pass PVI and early reconnection after 20-minute waiting after PVI were evaluated. Total procedure time, ablation time for PVI, and occurrence of procedure-related complication were collected. Results A total of 40 patients were included (mean age 64 years, 45% of persistent AF). Additional ablation other than PV was performed in 48% of patients, total procedure time was 77 minutes, and total PVI time was 9.9 minutes. With vHPSD PVI, all PVs first pass isolation rate was 60%; in terms of per PV, RSPV first-pass isolation was 88%, followed by LSPV and LIPV 85%, RIPV showed lowest first-pass isolation rate, 75% (Figure A). Most common RP sites was right carina, followed by left carina (Figure A). Compared to historical comparator, vHPSD PVI showed shorter procedure time, shorter ablation time for PVI, with numerically lower but statistically comparable first-pass PVI rate (Figure B). In total 560 PV segments in 40 patients, RSPV anterior, left carina, and right carina showed higher prevalence to be thick PV segments (over 60% of patients), followed by RPSV posterior, LSPV posterior, and RIPV anterior (over 40% of patients). Looking into ablation parameter detail, mean contact force was 10g, mean temperature was 47°C, and mean impedance drop was 8.4Ω. Compared to segments without RP, segments with RP showed thicker mean left atrial wall thickness grades, lower minimum contact force, higher maximum temperature, and lower minimum impedance drop. According to the left atrial wall thickness, thick PV segments showed higher prevalence of RP after first-pass PVI with vHPSD ablation. In segments with LAWT grade 3 or more, the RP rate was 9.1%. This thickness means thicker than 1.5 to 2.0 mm of thickness (Figure C). In 10% of patients (n=4) had audible or tactile steam-pops, visible char was confirmed in 5% of patients (n=2). There were no clinical complications. Conclusion PVI using vHPSD achieved shorter procedure time, shorter ablation time for PVI, and comparable first-pass PVI rate compared to historical comparator using ablation-index guided conventional power ablation. Thick segments had higher chance to have residual potential after first-pass PVI with vHPSD.

Long-term recurrence-free survival following second-generation cryoballoon ablation for persistent atrial fibrillation: role of the autonomic nervous system

Abstract Background The cardiac autonomic nervous system (ANS) plays a pivotal role in the regulation of atrial fibrillation (AF). Cryoballon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for AF. Purpose In our present study we evaluated the impact of vagal reactions (VRs), as a surrogate parameter for ANS modulation, on the long-term outcome of CB-ablation in patients with persistent AF (PERS AF). Methods Data from consecutive PERS AF patients undergoing primary CB-guided PVI for symptomatic drug refractory AF between 2013-2023 were analysed. VRs were defined as bradycardia &amp;lt; 40 beats/min, asystole or higher-degree atrioventricular block. Long-term follow-up data were assessed. AF-recurrence was defined as AF lasting &amp;gt; 30 seconds beyond a 3-month blanking period. Results A total of 250 consecutive patients (mean age 63.9±10.0 years, 30% female) were included. VRs were recorded in 61 patients (24%, mean age 64.2±13.0 years, 30% female). The mean follow-up duration amounted to 84±14 months. Within this observation period 101 patients (40%) developed AF-recurrence. Re-ablation procedures were performed in 61 patients (60%). Patients with PVI-associated VRs presented with a significantly higher estimated AF-free survival rate (log-rank p-value &amp;lt; 0.001) (Figure 1) and a significantly longer median AF-free survival time (75 months, interquartile range (IR) 63-92 months) compared to those without (69 months, IR 13-79 months) (p=0.002). Beyond that Kaplan-Meier plot analyses revealed significant gender differences (Figure 1). Multivariate cox regression analyses confirmed VRs (Confidence interval (CI) 0.294-0.838, Hazard Ratio (HR) 0.497, p=0.009) and male gender (CI 0.352-0.781, HR, 524, p=0.001) as independent predictors (IPs) for AF-free-survival. Conclusion CB-ablation procedure associated VRs and male gender seem to be associated with a favorable long-term outcome in PERS AF. Further studies are warranted to verify our observations.Kaplan Meier plot on long-term AF-free s

Association of atrial mechanical dispersion with atrial fibrillation recurrence following catheter ablation: results of the ASTRA-AF pilot study.

For patients with symptomatic drug-refractory atrial fibrillation (AF), catheter ablation to achieve rhythm control is an important therapeutic option. The atrial mechanical dispersion measured as standard deviation of the time to peak strain (SD-TPS) is associated with the risk of AF recurrence following catheter ablation. The study cohort prospectively enrolled n = 132 consecutive patients with paroxysmal (n = 88) or persistent AF (n = 44) presenting for de novo pulmonary vein isolation (PVI) and followed for 1year. We related left atrial (LA) volume, LA ejection fraction, SD-TPS, and global longitudinal strain of the left ventricle and clinical variables (sex, age, and type of AF) to AF recurrence. Kaplan-Meier curves showed higher AF recurrence rate with an increase of SD-TPS with the calculated cut-off of 38.6ms. Uni- and multivariable Cox regression analysis could show that SD-TPS had the highest relevance regarding AF recurrence with a HR of 1.05 (95% CI, 1.01; 1.09, p = 0.01) and HR of 1.05 (95% CI, 1.01; 1.09, p = 0.02) per 10ms increase. In the additional analyses for the model including the clinical variables age, sex, and type of AF with paroxysmal or persisting AF, SD-TPS did only show a trend and after adjusting for covariates, SD-TPS showed a HR of 1.04 (95% CI, 0.99; 1.09, p = 0.09) per 10ms increase. Atrial mechanical dispersion was associated with recurrent AF.

Abstract 15076: Long-Term Recurrence Free Survival in Second Generation Cryoballoon Ablation for Persistent Atrial Fibrillation: It’s All About the Autonomic Nervous System

Introduction: Cryoballon (CB)-guided pulmonary vein isolation (PVI) is an accepted treatment option for atrial fibrillation (AF). The cardiac autonomic nervous system (ANS) plays a crucial role in the regulation of AF. Hypothesis: ANS modulation has an impact on patients’ AF free survival following CB-ablation. The aim of this observational clinical trial was to analyze the impact of vagal reactions (VRs), as a surrogate parameter for ANS modulation, on the long-term outcome of CB-ablation in patients with persistent AF (PERS AF). Methods: Data from consecutive PERS AF patients treated with a CB-guided PVI for symptomatic drug refractory AF between 2013-2023 were analyzed. VRs were defined as bradycardia &lt; 40 beats/min, asystole or higher-degree atrioventricular block. All patients were continuously followed up in our outpatient clinic. AF-recurrence was defined as AF lasting &gt; 30 seconds beyond a 3-month blanking period. Results: A total of 250 consecutive patients (mean age 63.9 ± 10.0 years, 70% male) were included. VRs were recorded in 61 patients (24%). The mean follow-up duration amounted to 84±14 months. Within this observation period 101 patients (40%) developed AF recurrence a mean of 1.75 ± 0.80 times. Re-ablation procedures were performed in 61 patients (60%) a mean of 1.28 ± 0.55 times. Reconnected PVs were documented in 41 cases (67%). An additional substrate modification was performed in 34 procedures (42%). Patients with procedure associated VRs presented with a significantly higher estimated AF-free survival rate compared to those without (log-rank p-value=0.016) (Figure1). Multivariate analyses revealed the days to first AF recurrence following primary CB-ablation as an independent predictor for AF-free survival (CI 0.841-0.928, HR, 0.883, p&lt;0.01). Conclusions: CB-ablation procedure associated VRs seem to be associated with a favorable long-term outcome in PERS AF. Thus, our findings may influence future CB-ablation strategies.

Clinical outcomes of combined catheter ablation and left atrial appendage closure in elderly patients with nonvalvular atrial fibrillation.

Catheter ablation (CA) combined with left atrial appendage closure (LAAC) has emerged as a promising method to relieve symptoms while reducing the incidence of stroke in selected high-risk patients with atrial fibrillation (AF). We aimed to investigate the clinical outcomes of combined CA and LAAC in elderly patients. A total of 316 patients with symptomatic drug-refractory AF who underwent combined CA and LAAC between January 2016 and December 2020 were retrospectively included. Baseline characteristics, periprocedural complications, and clinical events during follow-up were recorded and compared between patients aged ≥ 75 years (n = 66) and <75 years (n = 250). Pulmonary vein isolation and satisfactory LAAC were achieved in all patients. No patients experienced death or stroke/transient ischemic stroke periprocedurally. After a median follow-up of 12.2 (6.7-24.4) months and 11.9 (5.5-23.6) months, the rate of sinus rhythm maintenance was comparable between the two groups (≥75 years: 78.8% vs. <75 years: 80.8%; log-rank test, p = 0.674). The median follow-up periods for clinical outcomes were 27.9 (9.3-44.8) months and 25.2 (10.8-45.7) months, respectively. In patients aged ≥ 75 years, one suffered ischemic stroke, and one experienced major bleeding event. In patients aged < 75 years, four had ischemic stroke, and eight had major bleeding events. Two patients aged < 75 years died during follow-up, while none of the patients aged ≥ 75 years died. Combining CA and LAAC was feasible, safe and effective in elderly patients with AF.

Growing thrombus adhesion on the left atrial wall after catheter ablation of atrial fibrillation.

Growing thrombus adhesion on the left atrial wall after catheter ablation of atrial fibrillation.

10-Year Outcomes of Patients With Non-Paroxysmal Atrial Fibrillation Undergoing Catheter Ablation.

Radiofrequency catheter ablation (RFCA) is commonly performed in patients with non-paroxysmal atrial fibrillation (AF), but because very long-term follow-up results of RFCA are limited, we investigated the 10-year RFCA outcomes of non-paroxysmal AF. We retrospectively enrolled 100 patients (89 men, mean age 53.5±8.4years) with drug-refractory symptomatic non-paroxysmal AF who underwent 3D electroanatomic-guided RFCA. Procedural characteristics at index procedures and clinical outcomes were investigated. In the index procedures, all patients had pulmonary vein isolation, 56 (56.0%), 48 (48.0%), and 32 (32.0%) underwent additional linear, complex fractionated atrial electrogram (CFAE) and non-pulmonary vein (NPV) foci ablations, respectively. After 124.1±31.7 months, 16 (16%) patients remained in sinus rhythm after just 1 procedure (3 with antiarrhythmic drugs [AAD]) and after multiple (2.1±1.3) procedures in 53 (53.0%) patients (22 with AAD). Left atrial (LA) diameter (hazard ratio HR 1.061; 95% confidence interval (CI) 1.020 to 1.103; P=0.003), presence of NPV triggers (HR 1.634; 95% CI 1.019 to 2.623; P=0.042) and undergoing CFAE ablation (HR 2.003; 95% CI 1.262 to 3.180; P=0.003) in the index procedure were independent predictors for recurrent atrial tachyarrhythmia. The 10-year outcomes of single RFCA in non-paroxysmal AF were unsatisfactory. Enlarged LA, presence of NPV triggers, and undergoing CFAE ablation in the index procedure independently predicted single-procedure recurrence. Multiple procedures are required to achieve adequate rhythm control.

Outcomes of very high-power short-duration ablation using 90w for pulmonary vein isolation in patients with atrial fibrillation: a real world observation study

Abstract Introduction Pulmonary vein isolation (PVI) ablation is the established gold standard therapy for patients with symptomatic drug refractory atrial fibrillation (AF). Advancements in radiofrequency (RF) ablation, have led to the development of the novel contact force-sensing temperature-controlled very high-power short-duration (vHPSD) RF ablation. This setting delivers 90W for up to 4 seconds with a constant irrigation flow rate of 8ml/min. The aim of this study was to compare procedural outcomes and safety with conventional radiofrequency ablation. Methods An observational study was conducted with patients who underwent first time PVI ablation from 2019 to 2021. The cohort was divided in to: 1) vHPSD ablation – QMODE+ via QDOT MICRO catheter, 2) QMODE via QDOT MICRO catheter and 3) Conventional power-controlled RF (PCRF) ablation via THERMOCOOOL SMARRTOUCH SF (STSF) catheter. The QMODE+ vHPSD ablation group was prospectively recruited while the QMODE and PCRF group were retrospectively collected. Primary outcomes were procedural success, PVI duration, ablation duration and incidence of perioperative adverse events. Secondary outcomes were intraprocedural morphine and midazolam requirement. Results A total of 155 patients were included in the study with 80, 30 and 45 patients in the QMODE+ (vHPSD), QMODE and PCRF, respectively. PVI was successfully attained in all patients. QMODE+ (vHPSD) demonstrated significantly reduced time required for PVI and total energy application in comparison to the QMODE and PCRF groups (68.3±3.30 vs. 92.9±4.86 vs. 93.6±4.34 min, P&amp;lt;0.0001; 9.7±0.452 vs. 33.9±0.452 vs. 36.0±1.56 min, P&amp;lt;0.0001, respectively) (Figure 1). Intravenous morphine and midazolam requirement was lower in the QMODE+ (vHPSD) group compared to the QMODE and PCRF groups (10.3±0.45 vs. 16.1±0.935 vs. 15.3±0.686 mg, P&amp;lt;0.0001; 4.05±0.402 vs. 8.63±1.07 vs. 8.58±0.821 mg, P&amp;lt;0.0001) (Figure 2). QMODE+ (vHPSD) observed a non-significant reduction in fluoroscopy time compared to QMODE and PCRF. One cardiac tamponade were observed in both the QMODE+ (vHPSD) and QMODE group while the PCRF group exhibited an embolic stoke and two pericardial effusions that did not require drainage. Conclusion In this study, QMODE+ (vHPSD) demonstrated a comparable safety profile to the other treatment arms. Procedural duration and energy application time was substantially reduced while a non-significant reduction was observed for fluoroscopy time for QMODE+. Furthermore, sedation requirement was reduced and thus potentially conveyed greater patient tolerability of the procedure when conducted with QMODE+. Notwithstanding the limitations of observational study design, these preliminary findings are promising with respect to periprocedural outcomes and safety of QMODE+. Longer term outcomes with respect to maintenance of sinus rhythm and symptomatic burden will be essential to assessing the overall efficacy of this novel technology. Funding Acknowledgement Type of funding sources: None.

Predictive value of HMGB1 for atrial fibrillation recurrence after cryoballoon ablation in paroxysmal atrial fibrillation patients.

Cryoballoon ablation (CBA) is recommended for patients with symptomatic drug refractory paroxysmal atrial fibrillation (pAF). However, substantial atrial fibrillation (AF) recurrence is common during follow-up. Searching for a potential biomarker representing both myocardial injury and inflammation to identify patients at high risk of AF recurrence after CBA is very meaningful for postoperative management of AF patients. To evaluate the clinical efficacy of high-mobility group box 1 (HMGB1) protein released from the left atrium to predict AF recurrence in pAF patients after CBA at 1-year follow-up. We included 72 pAF patients who underwent CBA. To determine the expression levels of HMGB1, left atrial blood samples were collected from the patients before CBA and after the procedure through the transseptal sheath. Patients were followed up for AF recurrence for 1 year. A total of 19 patients of the 72 experienced AF recurrence. The level of postoperative HMGB1 (HMGB1post) was higher in the AF recurrence group than in the AF non recurrence group (p = .03). However, no differences were noted in the levels of other biomarkers such as preoperative high-sensitivity C-reactive protein (hs-CRP), postoperativehs-CRP, and preoperative HMGB1 between the two groups. Multiple logistic regression analysis revealed that a higher level of serum HMGB1post was associated with AF recurrence (odds ratio: 5.29 [1.17-23.92], p = .04). Receiver operating characteristic analysis revealed that HMGB1post had a moderate predictive power for AF recurrence (area under the curve: 0.68; sensitivity: 72%; and specificity: 68%). The 1-year AF-free survival was significantly lower in patients with a high HMGB1post level than in those with a low HMGB1post level (hazard ratio: 3.81 [1.49-9.75], p = .005). In pAF patients who under went CBA, the level of HMGB1 after CBA was associated with AF recurrence and demonstrated a moderate predictive power. Thus, we offer a potential biomarker to identify pAF patients at high risk of AF recurrence.

Long-term Outcomes after Second-Generation Cryoballoon Ablation of Atrial Fibrillation and Analysis of Risk Factors Related to Recurrence

Objective: This study is aimed to analyze the long-term safety and effectiveness of second-generation cryoballoon (CB2) ablation in the treatment of atrial fibrillation (AF). Methods: Data from 760 consecutive patients in the Department of Cardiology, General Hospital of Northern Theater Command from August 2016 to December 2018 with drug-refractory symptomatic AF undergoing pulmonary vein isolation (PVI) using CB2 were assessed. Procedure-related safety and freedom from AF and atrial flutter/atria tachycardia through 3 years were determined. The risk factors related to atrial tachyarrhythmia recurrence were analyzed. Results: Acute PVI was achieved in 100% of the 760 patients. Radiofrequency application for additional focal ablation was needed in 11 (1.4%) patients and for 14 pulmonary veins (0.5%, 14/(760 × 4)) to achieve PVI. A total of 748 patients, including 539 with paroxysmal AF (PAF) and 209 with persistent AF (SAF) completed the follow-up, and only 12 (1.6%) patients were lost. The mean follow-up duration was (19 ± 8) months. The rate of major complications was 0.9%, including 0.8% of right phrenic nerve injury, which resolved before discharge. Freedom from all tachyarrhythmias was achieved in 75.0%, 69.4%, and 63.2% of patients with PAF, respectively, at 12-, 24-, and 36-month follow-up, and in 75.1%, 67.4%, and 60.9% for SAF, with no significant differences between the PAF and SAF groups. AF course and the rate of body weight gain were independent risk factors for recurrence at 12 months after ablation (P = 0.001 and P = 0.009, respectively). Conclusion: PVI using CB2 has a high acute success rate and good safety in the treatment of PAF and SAF. Long course of AF and weight gain after ablation were independent risk factors for recurrence.

Alteration of Skin Sympathetic Nerve Activity after Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation.

Autonomic system plays a pivotal role in the pathogenesis of paroxysmal atrial fibrillation (AF). Skin sympathetic nerve activity (SKNA) is a noninvasive tool for assessing sympathetic tone. However, data on changes in SKNA after ablation are limited. Here, we retrospectively enrolled 37 patients with symptomatic drug-refractory paroxysmal AF who underwent pulmonary vein isolation (PVI) with radiofrequency ablation (RFA) or cryoablation (CBA). SKNA was measured from the chest and right arm 1 day prior to ablation, as well as 1 day and 3 months after ablation. One day after ablation, the SKNA-Arm increased from 517.1 µV (first and third quartiles, 396.0 and 728.0, respectively) to 1226.2 µV (first and third quartiles, 555.2 and 2281.0), with an increase of 179.8% (125% and 376.0%) (p < 0.001); the SKNA-Chest increased from 538.2 µV (first and third quartiles, 432.9 and 663.9) to 640.0 µV (first and third quartiles, 474.2 and 925.6), with an increase of 108.3% (95.6% and 167.9%) (p = 0.004), respectively. In those without recurrence, there was a significant increase in SKNA 1 day after ablation as compared with those before ablation. Twelve patients received SKNA measurement 3 months after ablation; both SKNA-Arm (p = 0.31) and SKNA-Chest (p = 0.27) were similar to those before ablation, respectively. Among patients with symptomatic drug-refractory paroxysmal AF receiving PVI, increased SKNA was observed 1 day after ablation and returned to the baseline 3 months after ablation. Elevation of SKNA was associated with lower early and late recurrences following ablation.

Relationship between electrical activity and left atrial volume during atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Pulmonary veins (PV) ostia were previously identified as the left atrium (LA) areas with the shortest refractory period during sinus rhythm. Pulmonary veins isolation (PVI) became standard of care, but clinical results are still suboptimal. Currently, atrial fibrillation (AF) cycle length mapping (CLM) is possible due to a special tool of the Carto® electroanatomical mapping, which identifies areas in the left atria with shortest refractory period, during AF. Purpose Using this new EAM feature, our study aimed to assess the relationship between short refractory period LA areas and left atrial volume and AF type, known predictors of AF relapse. Methods Retrospective analysis of an unicentric registry of individuals with symptomatic drug-refractory AF who underwent PVI AF ablation with Carto® EAM. CLM was performed. CL maps were created with a high-density mapping Pentaray® catheter before and after PVI. We assessed areas of short cycle length (SCL) (defined as 120 to 250ms), and their relationships with complex fractionated atrial electrograms (CFAE), and low-voltage zones (from 0.1 to 0.3mV). Results A total of 35 patients (21 men, median age 62 IQR 53-71 years) were included. Most patients presented with persistent AF (n=23, 66%), and 8 patients (23%) had a previous PVI. The mean shortest measured cycle length in AF was 134ms (SD ± 23ms). There was a negative correlation between LA volume and SCL areas after PVI (Spearman Correlation coefficient [ρ] = - 0.47, P = 0.037). There was no correlation between LA volume and SCL areas before the PVI procedure (ρ = -0.06, P = 0.776), nor between AF type and SCL (ρ = -0.118, P = 0.620). All patients presented areas of SCL located in the PVs or their insertion, 76% in the posterior/roof region adjacent to the left superior pulmonary vein (LSPV) and 76% in the anterior region of the wall adjacent to the right superior pulmonary vein (RSPV). These two areas remained the fastest even after PVI. The anterior mitral region rarely presented SCL (16%). SCL were related to low-voltage areas in 93% and were adjacent to CFAE in 84% of the cases. Low-voltage areas and CFAE were more frequent and had a larger LA dispersion than SCL. Conclusion Our study shows that LA volume, not AF type, is correlated with remaining SCL areas after a pulmonary vein isolation procedure. This finding suggests a possible causal link between increased LA volume and AF relapse post-PVI. More studies are needed to assess the role of the SCL areas as a potential ablation target and their impact on AF ablation outcomes.

Procedural characteristics of pulmonary vein isolation with high-power short-duration setting compared to conventional setting

PurposeThe purpose of this study was to investigate the safety and efficacy of high-power short-duration (HP-SD) ablation compared to conventional ablation in patients with atrial fibrillation (AF).MethodsWe enrolled consecutive 158 drug-refractory symptomatic AF patients (119 males, mean age 63 ± 10 years) who had undergone first radiofrequency pulmonary vein isolation (PVI). PVI was performed using the conventional setting (20–35 W) in 73 patients (Conventional group) and using the HP-SD setting (45–50 W) in 85 patients (HP-SD group). The rate of first pass isolation, remaining gaps after circumferential ablation, dormant conduction, and the radiofrequency application time in each pulmonary vein (PV) were compared between the groups.ResultsThe first pass isolation ratio was significantly higher in the HP-SD group than in the Conventional group (81% vs. 65%, P = 0.027) in the right PV, but did not differ in the left PV. The remaining gaps were fewer in the right superior PV (4% vs. 21%, P = 0.001) and left inferior PV (1% vs. 8%, P = 0.032) areas, and the radiofrequency application time in each PV was shorter (right PV, 12.0 ± 8.9 min vs. 34.0 ± 31.7 min, P < 0.001; left PV, 10.6 ± 3.6 min vs. 25.7 ± 22.3 min, P < 0.001) in the HP-SD group than in the Conventional group.ConclusionThe use of the HP-SD setting might contribute to improve the first pass isolation rate and to shorten the radiofrequency application time in each PV.

High vagal tone predicts pulmonary vein reconnection after cryoballoon ablation for paroxysmal atrial fibrillation.

Pulmonary vein (PV) isolation is an established treatment for paroxysmal drug-refractory atrial fibrillation (AF). High parasympathetic tone and reconnection of PVs have demonstrated to be possible culprits of AF recurrence after ablation. Our aim was to investigate the association between parasympathetic tone and reconnected PVs in patients with paroxysmal AF. Consecutive patients who underwent a redo catheter ablation procedure for atrial tachyarrhythmia recurrence by means of 3D electroanatomic mapping with documentation of presence or absence of PVs reconnection following an initial procedure of cryoballoon (CB) ablation for symptomatic drug-refractory paroxysmal AF were screened for the study. A total of 92 patients were included, of whom 50 (54.35%) were males. Reconnected PVs were found in 64 (69%) patients. PVs reconnection could be predicted by DC (C-statistic = .770), by SDNNI (C-statistic = .714) and by absolute VLF power (C-statistic = .722), while right-sided PVs reconnection could be better predicted by DC (C-statistic = .848) and by SDNNI (C-statistic = .761). In multivariate binary logistic regression analysis, a DC value ≥6.45 ms and an absolute VLF power value ≥160 ms2 were associated with three times and five times higher odds of PVs reconnection, respectively. On a vein-per-vein analysis, absolute VLF power ≥160 ms2 was associated with three times higher odds, while reaching of -40°C within 60 s was associated with three times lower odds of PVs reconnection. High parasympathetic tonus accurately predicts PVs reconnection. On a vein-per-vein analysis, parasympathetic markers along with biophysical parameters predicted PVs reconnection. On a case-by-case analysis, parasympathetic markers were the only predictors of PVs reconnection, thus being a robust PVs reconnection prediction tool.

10-year clinical outcomes after radiofrequency catheter ablation for atrial fibrillation. A single center experience

Abstract Background Radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) is becoming a routine procedure to treat patients with drug-refractory symptomatic AF. However, data regarding very long-term clinical outcomes is limited. The aim of the present study was to evaluate the 10-year clinical outcomes of patients who underwent RFCA for paroxysmal and persistent AF. Methods We retrospectively enrolled 503 consecutive patients (mean age 66,9±9,51 years; 71,6% male) who underwent RFCA for drug-refractory symptomatic AF between February 2004 and June 2011. Follow-up information was obtained using medical records and/or telephonic interviews with the patient, relatives and/or referring physicians. Results Among 503 patients enrolled in this study, 362 had paroxysmal atrial fibrillation (PAF) and 141 had persistent atrial fibrillation (PeAF) (72% and 28%, respectively). Mean follow-up was 8,84±3,05 years. The 10-year event-free rate for recurrent atrial tachyarrhythmia (AT) after the first procedure was 44,5% (49,4% for PAF vs 31,9% for PeAF; p=0,002 by log-rank test) and 81,9% after the last procedure (87,3% for PAF and 67,9% for PeAF; p≤0,001 by log-rank test). AT recurrence was observed most commonly during the first 12 months of the initial procedure (56%), with only 18% of them occurring after 60 months. Multivariate analysis revealed that persistent AF (hazard ratio=1,366; 95% confidence interval 1,058–1,76; p=0,017) and duration of AF &amp;gt;5 years (hazard ratio=1,357; 95% confidence interval 1,064–1,732; p=0,005) were independent risk factors for AT recurrence. Regarding adverse events, there were 24 (4,8%) hospitalizations for acute decompensated heart failure, 20 (4%) ischemic strokes and 14 (2,8%) bleeding complications requiring hospital admissions. Patients taking oral anticoagulation and antiarrhythmic drugs at the end of the study accounted for 32,8% and 16,7% respectively. Conclusions RFCA for AF provided favorable results in terms of arrhythmia event-free survival in long-term follow-up with better results in patients with paroxysmal AF. Persistent AF and long-standing AF (beyond 5 years) were associated with AT recurrence. Despite the large number of patients who discontinued oral anticoagulation, thromboembolic adverse events were rare. Funding Acknowledgement Type of funding sources: None.

A multicentered evaluation of the waiting period after PVI guided by the Ablation Index

Abstract Background Since the widespread availability of contact-force sensing catheters the need of a waiting period has not been reassessed in paroxysmal atrial fibrillation (AF) ablation. Objective The purpose of this study was to evaluate if pulmonary vein isolation (PVI) guided by the Ablation Index (AI) could spare the need for a waiting phase. Methods This multicentre, prospective, randomized study consecutively recruited patients referred for first-time catheter ablation of symptomatic drug-refractory paroxysmal AF from May 2019 to February 2020. Patients performed PVI tailored to different AI values according to the different left atrium walls (550 for anterior, 500 for roof, 450 for inferior and 400 for posterior). Patients were enrolled in 1:1 ratio to PVI and 20 min of waiting time versus PVI without a waiting period. Acute reconnection (either spontaneous or after adenosine) and 1-year arrhythmia freedom were analyzed. Results The study included 124 patients (61 in the waiting period group and 63 in the group without the waiting period). There was no significant differences between groups regarding baseline characteristics, echocardiographic and procedure data. There were no significant differences between both groups regarding the first-pass PV isolation (P=0.49) and the presence of low voltage areas (P=0.71). Median PVI time (P=0.40), median fluoroscopy time (P=0.35) and median overall procedure time (P=0.70) were also similar between groups. The acute PVR rate was similar between both groups (8.2% for the waiting period group vs 11.1% in the group without a waiting phase, P=0.40). After a median follow-up of 14 (IQR 12–18) months, there was no significant difference on the arrhythmia recurrence between groups (4.9% for the waiting group vs 12.7% for the group without a waiting phase, P=0.13). Both groups presented a similar arrhythmia freedom over time (log rank P of 0.109). The waiting period time was not a predictor of recurrence during follow-up (p=0.13). Conclusion PVI guided by Ablation Index preclude the need of a waiting phase. Adding a 20-minute waiting period did not significantly increase the acute PV reconnection, neither improve the 1-year arrhythmia freedom. Funding Acknowledgement Type of funding sources: None.

Results and Predictive Factors After One Cryoablation for Persistent Atrial Fibrillation

Cryoballoon pulmonary vein isolation (PVI) for persistent atrial fibrillation (AF) ablation is an increasingly used strategy. We aimed to determine the results and predictors of arrhythmia recurrence after a single procedure of cryoballoon PVI for patients with persistent and long-standing persistent AF. We included all consecutive patients who underwent cryoballoon PVI for the treatment of persistent symptomatic drug-refractory AF since 2012. All patients were prospectively followed to detect the recurrence of atrial tachyarrhythmia (ATa). Predictors of recurrence were assessed. Cryoballoon PVI was performed on 399 patients with persistent AF, among whom 52 (13%) had long-standing persistent AF. Patients with long-standing persistent AF had a significantly larger left atrium than those with persistent AF. A 28-mm cryoballoon was used for 322 patients (93%). In total, 359 patients (90%) completed the 12-month follow-up visit and the median follow-up was 24 months (interquartile range 43 to 13). The 2-year probability of freedom from ATa recurrence was 51% for persistent AF and 27% for long-standing persistent AF. Long-standing persistent AF and left atrial area/volume were independent predictors of ATa recurrence. Ten patients (2.5%) experienced phrenic nerve palsy, 1 tamponade (0.25%), 2 stroke (0.5%), 2 pericardial effusions (0.5%), and 5 vascular complications (1.25%). In conclusion, 2-year ATa-free survival rates were 51 and 27% for persistent and long-standing persistent AF patients, respectively. Complications were rare. Long-standing persistent AF and left-atrial area/volume were predictors of recurrence.

The impact of height on recurrence after index catheter ablation of paroxysmal atrial fibrillation.

The relationship between height and incident atrial fibrillation (AF) has recently been demonstrated. We aimed to evaluate the impact of height on outcomes of ablation in patients with drug-refractory symptomatic paroxysmal AF (PAF). A total of 689 patients (470 males; age, 53.0 ± 11.7years) with symptomatic paroxysmal AF receiving index catheter ablation (CA) between 2003 and 2013 were enrolled in this study. The baseline characteristics, ablation, and follow-up results were evaluated. The patients were categorized according to the quartiles of height for each sex. Patients in the lower quartiles of height had a lower incidence of AF recurrence (log-rank p = 0.022). Height in female patients was strongly associated with AF recurrence (p = 0.027) after an index ablation in the 6.33 ± 4.32years of follow-up. Female patients > 159cm in height had a higher likelihood of AF recurrence after index CA (HR = 2.01, 95% CI: 1.24-3.25, p = 0.005) than that in those below this height. In computed tomography (CT) scan, the superoinferior diameter of the left atrium (LA) correlated with body height in females, but not in male patients. Height is associated with AF recurrence after the index CA of PAF in female patients. In Asian populations, women above height 159cm are twice as likely to have AF recurrence post-ablation as shorter women.