Drug-refractory Atrial Fibrillation Research Articles

Maintenance of Sinus Rhythm Is Associated With Lower Incidence of Stroke in Patients With Drug-Refractory Atrial Fibrillation.

Recent studies have demonstrated that early rhythm control for first-line treatment of atrial fibrillation (AF) improved cardiovascular outcomes. However, there is limited data regarding the long-term outcome of patients who failed antiarrhythmic drugs and who refuse radiofrequency catheter ablation (RFCA). Patients with AF who were refractory to antiarrhythmic drugs and had refused further rhythm control attempts via RFCA were retrospectively identified and propensity-score (PS) matched with thosewho had been treated with RFCA. The primary outcome of interest was all-cause mortality or ischemic stroke. A total of 169 patients who refused rhythm control with RFCA and PS matched 169 patients who had been treated with RFCA were included for analysis. During a mean follow-up of 4.3 (2.3;6.9) years, maintenance of sinus rhythm was more achieved in RFCA group (7 [4.1%] in Refuse group vs. 133 [78.7%] in RFCA group, p < 0.001). The incidence of ischemic stroke was significantly higher in patients who refused RFCA compared with patients who underwent RFCA (2.96 per 100 person-years in the Refused group vs. 0.74 per 100 person-years in the RFCA group, log-rank p < 0.001), but all-cause mortality was not significantly different (log-rank p = 0.8). Refusal of attempted rhythm control via RFCA was an independent risk factor for ischemic stroke on multivariate Cox analysis (hazard ratio [HR] 3.2; 95% confidence interval [CI] 1.2-8.53, p = 0.02). In patients with antiarrhythmic drug-refractory AF, the risk of stroke was significantly higher in patients who refused rhythm control via RFCA compared with that of those treated with RFCA.

Maintenance of sinus rhythm is associated with lower incidence of stroke in patients with drug-refractory atrial fibrillation

Abstract Introduction Recent studies have demonstrated that early rhythm control for first-line treatment of atrial fibrillation (AF) improved cardiovascular outcomes. However, there is limited data regarding the long-term outcome of patients who failed antiarrhythmic drugs and who refuse radiofrequency catheter ablation (RFCA). Methods Patients with AF who were refractory to antiarrhythmic drugs and had refused further rhythm control attempts via RFCA were retrospectively identified and propensity-score matched with who had been treated with RFCA. The primary outcome of interest was all-cause mortality or ischemic stroke. Results A total of 169 patients who refused rhythm control with RFCA and propensity-score matched 169 patients who had been treated with RFCA were included for analysis. During a mean follow-up of 4.3[2.3;6.9] years, maintenance of sinus rhythm was more achieved in RFCA group (7 [4.1%] in Refuse group vs. 133 [78.7%] in RFCA group, p&amp;lt;0.001). the incidence of ischemic stroke was significantly higher in patients who refused RFCA compared with patients who underwent RFCA (24 [14.2%] vs. 6 [3.5%], log-rank p&amp;lt;0.001), but all-cause mortality was not significantly different (log-rank p=0.8). Refusal of attempted rhythm control via RFCA was an independent risk factor for ischemic stroke on multivariate Cox analysis (hazard ratio 3.2; 95% confidence interval 1.2 to 8.53, p=0.02). The risk of major adverse cardiovascular events (MACE) were also significantly higher in Refuse group (31 [18.3%] vs. 12 [7.1%], HR 3.83, 95% CI 1.57-9.37, p=0.003). Conclusion In patients with antiarrhythmic drug-refractory AF, maintenance of sinus rhythm was significantly different dependent on rhythm control via RFCA, therefore the risk of stroke was significantly higher in patients who refused rhythm control via RFCA compared with that of those treated with RFCA.

The predictive value of left atrial functional parameters for recurrence of atrial fibrillation after catheter ablation in patients

Abstract Background Catheter ablation (CA) is a first-line treatment option for patients with symptomatic or drug-refractory atrial fibrillation (AF), yet the recurrence rate of AF post-CA remains considerably high. Studies have reported that left atrial (LA) functional parameters can serve as predictive factors for AF recurrence, however, the results remains controversial. Purpose This study aims to investigate the predictive value of LA functional parameters for AF recurrence following CA in patients. Methods We prospectively enrolled patients with AF who underwent CA for the first time from June 2022 to May 2023 and met the inclusion criteria at our institution. All patients underwent pre-ablation evaluation of LA structure and function, including LA diameter (LAD), LA maximum volume (LAVmax), LA minimum volume (LAVmin), LA pre-systolic volume (LAVpre), LA reservoir strain (LASr), LA strain conduit (LAScd), LA contraction strain (LASct), and LA ejection fraction (LAEF) using three-dimensional speckle tracking echocardiography. AF recurrence was defined as atrial tachycardia occurring 3 months after ablation and lasting longer than 30s. Patients were followed up for 9 months post-CA , and the primary end point was any atrial tachycardia occurring at 3 months after ablation. Results A total of 85 patients with AF were ultimately included in this study, with an average age of 68.9±11.0 years, 54.2% of whom were male. During the 9-month follow-up, 30 patients (35.29%) experienced recurrence postoperatively, while 55 patients (64.71%) still maintained sinus rhythm. Compared with the AF non-recurrence group, the AF recurrence group had significantly increased LAD (46.4±5.5mm vs. 42.3±4.5mm, p&amp;lt;0.05), LAVmax (80.7±21.3mL vs. 67.1±22.0mL, p&amp;lt;0.05), LAVmin (63.8±18.0mL vs. 42.8±16.9mL, p&amp;lt;0.05) and LAVpre (72.4±19.4mL vs. 53.9±16.8mL, p&amp;lt;0.05). Meanwhile, in AF recurrence group, LAEF (21.7±6.8% vs. 37.5±8.0%, p&amp;lt;0.05), LASr (5.1±3.1% vs. 12.0±5.4%, p&amp;lt;0.05), LAScd (-4.0±3.6% vs. -7.3±5.7%, p&amp;lt;0.05), and LASct (-1.0±3.8% vs. -3.3±4.9%, p&amp;lt;0.05) were significantly decreased. Multivariate logistic regression analysis revealed that LASr (OR=0.640, 95%CI 0.425-0.964, p&amp;lt;0.05) and LAEF (OR=0.816, 95%CI 0.694-0.960, p&amp;lt;0.05) were independent risk factors for predicting AF recurrence. ROC curve analysis showed that both LAEF (AUC=0.935, 95%CI 0.871-0.999) and LASr (AUC=0.903, 95%CI 0.833-0.973) possess high predictive values. Furthermore, the combined model of LAEF and LASr (AUC=0.954, 95%CI 0.905-1.000) had a greater predictive value than any one of the two indicators (p&amp;lt;0.05). Conclusion Taken together, these findings indicate that LAEF and LASr are independent predictors of AF recurrence following CA in patients with AF. Combination of the two indicators can more accurately assess the risk of recurrence in AF patients post-CA.

Impact of conduction velocity in left atrium assessing with omnipolar technology in patients with atrial fibrillation

Abstract Background There is increased interest in exploring substrate of atrial fibrillation (AF) and recent studies have shown that atrial conduction velocity (CV) reflects the electrophysiological phenomena and plays key role in perpetuating AF. The novel omnipolar technology (OT) use three unipolar and two orthogonal bipolar signals allow us to analyze the voltage, activation direction, and CV independent of catheter position. Objective The purpose of the present study was to evaluate if the left atrium (LA) CV which assessed by OT predict the any atrial tachy-arrhythmia (AT) recurrence after initial AF ablation. Methods We enrolled 58 consecutive patients who underwent initial pulmonary vein isolation (PVI) for drug refractory AF. (mean age: 68.2±10.2 years old, 32 male(55.1%), 32 persistent AF(55.1%), CHADS2 score:1.6±0.6). After electrical PVI was achieved and remained in sinus rhythm, the LA was mapped with high density mapping catheter (Advisor HD Grid, Abott USA) utilizing with the novel OT combined with Ensite X system (Abott, USA). The conduction distance and conduction times were measured from the earliest activation site to the latest activation site in LA (Figure 1). Each conduction velocity in anterior, posterior, and septal area were also calculated as conduction distance divided by conduction time. The LA voltage was also measured. Results During a mean follow up period of 316±143 days, the recurrence of AT after initial PVI was observed in 9 (15.5%) patients. There were no significant differences in baseline demographics between AT recurrence and non-recurrence group (mean age:66±13.3 vs 68.5±10.5 years old P=0.66, CHADS2 score: 1.5±0.57 vs 1.68±0.62 P=0.59, proportion of persistent AF: 15.4% vs 15.5% P=0.82, LA volume: 102±35.9 vs 93.6±37.3ml P=0.63). The earliest activation site in LA were identified in 3 areas including anterior site of right pulmonary vein (51.7%), Bachmann bundle area (41.4%), and antero-septal area (6.89%) (Figure 2). In patients with AT recurrence, the CV in LA was significantly slower than those without AF recurrence(0.61±0.21 vs 0.81±0.16 m/s, P=0.036) whereas the whole LA voltage was not (1.52±0.75 vs 2.22±1.06 mv, P=0.28). The CV in each LA portion are similar between recurrence and non-recurrence AT group. (anterior:0.57±0.24 vs 0.81±0.23 m/s, P=0.18, posterior: 0.87±0.18 vs 1.2±0.49 m/s P=0.36, septal: 0.89±0.76 vs 1.15±0.39 m/s, P=0.41). Conclusion The earliest activation site in LA was varied in each case. The whole CV in LA is a predictor of AF recurrence after PVI whereas the CV of each LA portion and LA voltage was not.

Discordance between left atrial volume and scar burden in patients with atrial fibrillation and its impact on atrial fibrillation recurrence after catheter ablation

Abstract Background Large left atrial (LA) volume and a high burden of LA low voltage zone (LVZ) are associated with atrial fibrillation (AF) recurrence after AF catheter ablation. There is a scarcity of information on the association between LA volume and LVZ and its impact on the risk of AF recurrence. Purpose To investigate the relationship between the LA volume and LVZ, as well as how these factors contribute to the recurrence of atrial fibrillation (AF). Methods From Nov 2021 to Oct 2023, drug-refractory AF patients who underwent AF catheter ablation were included. LA volume was assessed using the LA volume index (LAVI) using echocardiography. The LVZ was evaluated by conducting high-density electroanatomical mapping using a multipolar catheter. The cut-off value associated with AF recurrence was 48ml/m2 in LAVI and 4.5% in scar burden. Patients were categorised into four groups according to the LAVI and scar burden: Group 1 (Low LVZ and small LA), group 2 (Low LVZ and large LA), group 3 (High LVZ and small LA), and group 4 (High LVZ and large LA). Results A total of 170 patients were included (mean age 62± 9 years, 82% of men, 68.2% of non-paroxysmal AF and 81 [48%] in group 1; 32 [19%] in group 2, 27 [16%] in group 3, 30 [17%] in group 4, respectively). Among total, mean follow-up duration was 266.5 ± 174.4 days, and 8.8% of patients received additional LA ablation beyond pulmonary vein isolation. Among the four groups, group 2 and 4 were significantly associated with higher risks of AF recurrence compared to group 1 (HR 2.36 [1.04-5.34], p=0.039; 3.56 [1.59-7.95], p=0.002, respectively). The risk of AF recurrence was highest in group 4, followed by group 2 (log-rank P=0.002). Comparing group 2 and 3, AF recurrence occurred predominantly within 6-month after catheter ablation in group 2, while after 1-year in group 3 (log-rank P=0.83). Conclusion About one-third of patients showed discordance between the LAVI and LVZ, which are both independent predictors for AF recurrence. A substantial LA volume seems to contribute to early AF recurrence, whereas a high scar burden appears to affect late AF recurrence.

Impact of proximity of left atrium to descending aorta on left inferior pulmonary vein triggers or drivers of atrial fibrillation: A risk score model

BackgroundPrior studies have investigated cardiac anatomy and clinical parameters as predictors for pulmonary vein and non–pulmonary vein triggers. ObjectiveWe aimed to assess the link between the descending aorta to left inferior pulmonary vein (Dao-LIPV) distance and the occurrence of triggers and drivers in atrial fibrillation (AF) ablation procedures. MethodsDrug-refractory AF patients who underwent first-time index catheter ablation from January 2010 to December 2019 were retrospectively assembled. The Dao-LIPV distance was measured from preablation pulmonary vein computed tomography. Patients were assigned to groups on the basis of the presence of LIPV triggers or drivers. Multivariate logistic regression was used to identify risk factors. ResultsA total of 886 consecutive patients with drug-refractory AF were studied, and 63 (7.1%) patients were identified to have LIPV triggers or drivers. The Dao-LIPV distance had a better predictive performance (area under the curve, 0.70) compared with persistent AF (area under the curve, 0.57). Multivariate logistic regression analysis showed that Dao-LIPV distance ≤2.5 mm (odds ratio, 3.96; 95% CI, 2.15–7.29; P < .001) and persistent AF (odds ratio, 1.73; 95% CI, 1.02–2.94]; P = .044) were independent predictors for the presence of LIPV triggers or drivers. A risk score model was established to predict the probability of LIPV triggers or drivers with persistent AF (10.2%), Dao-LIPV distance ≤2.5 mm (11.4%), and both (15.0%). ConclusionThe proximity of the Dao-LIPV was correlated to the presence of LIPV triggers or drivers. We developed a risk score model indicating that persistent AF and Dao-LIPV distances ≤2.5 mm significantly increase the risk of LIPV triggers or drivers, aiding electrophysiologists in preparing for and performing catheter ablation more effectively.

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.

Long-Term Changes in Atrial Arrhythmia Burden After Renal Denervation Combined With Pulmonary Vein Isolation: SYMPLICITY-AF

BackgroundThe autonomic nervous system plays an important role in atrial fibrillation (AF) and hypertension. Renal denervation (RDN) lowers blood pressure (BP), but its role in AF is poorly understood. ObjectivesThe purpose of this study was to investigate whether RDN reduces AF recurrence after pulmonary vein isolation (PVI). MethodsThis study randomized patients from 8 centers (United States, Germany) with drug-refractory AF for treatment with PVI+RDN vs PVI alone. A multielectrode radiofrequency Spyral catheter system was used for RDN. Insertable cardiac monitors were used for continuous rhythm monitoring. The primary efficacy endpoint was ≥2 minutes of AF recurrence or repeat ablation during all follow-up. The secondary endpoints included atrial arrhythmia (AA) burden, discontinuation of class I/III antiarrhythmic drugs, and BP changes from baseline. ResultsA total of 70 patients with AF (52 paroxysmal, 18 persistent) and uncontrolled hypertension were randomized (RDN+PVI, n = 34; PVI, n = 36). At 3.5 years, 26.2% and 21.4% of patients in RDN+PVI and PVI groups, respectively, were free from the primary efficacy endpoint (log rank P = 0.73). Patients with mean ≥1 h/d AA had less daily AA burden after RDN+PVI vs PVI (4.1 hours vs 9.2 hours; P = 0.016). More patients discontinued class I/III antiarrhythmic drugs after RDN+PVI vs PVI (45% vs 14%; P = 0.040). At 1 year, systolic BP changed by −17.8 ± 12.8 mm Hg and −13.7 ± 18.8 mm Hg after RDN+PVI and PVI, respectively (P = 0.43). The composite safety endpoint was not significantly different between groups. ConclusionsIn patients with AF and uncontrolled BP, RDN+PVI did not prevent AF recurrence more than PVI alone. However, RDN+PVI may reduce AF burden and antiarrhythmic drug usage, but this needs further prospective validation.

Efficacy and safety of a novel hexaspline pulsed field ablation system in patients with paroxysmal atrial fibrillation: the PLEASE-AF study.

Pulsed field ablation (PFA) is an emerging non-thermal ablative modality demonstrating considerable promise for catheter ablation of atrial fibrillation (AF). However, these PFA trials have almost universally included only Caucasian populations, with little data on its effect on other races/ethnicities. The PLEASE-AF trial sought to study the 12-month efficacy and the safety of a multi-electrode hexaspline PFA catheter in treating a predominantly Asian/Chinese population of patients with drug-refractory paroxysmal AF. Patients underwent pulmonary vein (PV) isolation (PVI) by delivering different pulse intensities at the PV ostium (1800 V) and atrium (2000 V). Acute success was defined as no PV potentials and entrance/exit conduction block of all PVs after a 20-min waiting period. Follow-up at 3, 6, and 12 months included 12-lead electrocardiogram and 24-h Holter examinations. The primary efficacy endpoint was 12-month freedom from any atrial arrhythmias lasting at least 30 s. The cohort included 143 patients from 12 hospitals treated by 28 operators: age 60.2 ± 10.0 years, 65.7% male, Asian/Chinese 100%, and left atrial diameter 36.6 ± 4.9 mm. All PVs (565/565, 100%) were successfully isolated. The total procedure, catheter dwell, total PFA application, and total fluoroscopy times were 123.5 ± 38.8 min, 63.0 ± 30.7 min, 169.7 ± 34.6 s, and 27.3 ± 10.1 min, respectively. The primary endpoint was observed in 124 of 143 patients (86.7%). One patient (0.7%) developed a small pericardial effusion 1-month post-procedure, not requiring intervention. The novel hexaspline PFA catheter demonstrated universal acute PVI with an excellent safety profile and promising 12-month freedom from recurrent atrial arrhythmias in an Asian/Chinese population with paroxysmal AF. ClinicalTrials.gov Identifier: NCT05114954.

Cardiovascular magnetic resonance 3D LGE imaging for atrial fibrillation ablation

Abstract Objective To assess feasibility and reliability of cardiac magnetic resonance (CMR) imaging in visualizing left atrial (LA) structural changes that patients with paroxysmal atrial fibrillation (PAF) undergo acutely and long-term post ablation. Two different ablation methods i.e pulsed filed ablation (PFA) and cryoablation were studied. Background Pulmonary vein (PV) isolation has become the cornerstone technique for catheter ablation in patients with drug-refractory atrial fibrillation (AF). At present, almost all ablation technologies are mediated by a thermal effect. Recently, pulsed field ablation (PFA) has been introduced as a new energy source. PFA is a non-thermal ablative modality in which high voltage ultra-short pulses are applied to target tissue, while preserving the extracellular matrix architecture, nerves, and microvascular structures. Few data exist showing different structural LA changes between the two methods using Three-Dimensional (3D) Late Gadolinium Enhancement (LGE) Imaging. Methods CMR imaging was performed pre-ablation, acutely (&amp;lt;24 h), and 3 months post-ablation in 10 patients with paroxysmal atrial fibrillation (AF) undergoing pulmonary vein (PV) isolation with PFA (n = 5) or cryoablation (n = 5). 3D LGE and T2-weighted images were analysed. We obtained two data sets of 3D whole heart LGE imaging with high resolution, 20minutes post gadolinium injection. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D LGE with Dixon water-fat separation. 3D LGE data were analysed using a dedicated (ADAS LA) software in order to produce a 3D-LA model visualization of LGE areas. Results In the acute stage, LGE volume was 50% larger after PFA vs. cryoablation (P &amp;lt; 0.001), and oedema on T2 imaging was significantly smaller (visual estimation) on PFA cases. LGE rings surrounding PV ostia were more homogeneous after PFA, with no sign of microvascular damage or intramural hemorrhage as compared to cryoablation cases. In the chronic stage, the majority of acute LGE had disappeared after PFA, whereas most LGE persisted after cryo-ablation. The two 3D LGE sequences used for analysis showed complete agreement in the visualization of atrial scar with superior image quality of the novel sequence. The mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. Conclusions CMR imaging may help in visualization and understanding of LA structural remodeling post different ablation techniques.

Radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique: 9-year outcome

Abstract Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Cryoablation has been shown to be a safe and effective technique for pulmonary vein isolation. However, there is a significant arrhythmia recurrence rate after cryoablation procedures and there are no established strategies for redo procedures in these patients. Therefore, we have summarized our experience with radiofrequency catheter ablation for redo procedures after pulmonary vein isolation with the cryoballoon technique (including an analysis of pulmonary vein conduction recovery patterns after procedures performed with the first or second generation cryoballoon). Methods Two hundred and twenty patients (paroxysmal AF: 140 patients, persistent AF: 80 patients) had to undergo a redo procedure after initially successful circumferential PV isolation with the cryoballoon technique (First generation: 110 patients (group A); second generation: 110 patients (group B)). The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy (three-dimensional mapping system) depending on the intra-procedural findings. Results During the redo procedure, a mean number of 1.6 re-conducting PVs were detected (using a circular mapping catheter; group A: 2.2 re-conducting PVs, group B: 1.0 re-conducting PVs). There was a slightly higher incidence of chronic PV reconnections related to the left-sided PV ostia than to the right-sided PVs in both groups. Furthermore, sites of chronic PV reconnection were found more frequently in the inferior parts of the PV ostia than in the superior parts. In 97 patients in group A, a segmental approach was sufficient to eliminate the residual PV conduction because there were only a few recovered PV fibers (1-3 reconnected PVs; group A1). In the remaining 13 patients in group A, a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction of all four pulmonary veins (group A2). In group B, a segmental approach was sufficient in nearly all patients (109/110) because there was only a minor reconnection of 1-2 PVs. All recovered PVs could be isolated sucessfully again. At 108-month follow-up, 69.1 % of all patients were free from an arrhythmia recurrence (152/220 patients; group A: 72/110 patients (65.5 %), group B: 80/110 patients (72.3 %)). There were no major complications in both groups. Conclusions In patients with an initial circumferential PVI using the cryoballoon technique, a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation. In most cases only a few re-conducting PV fibers were found and therefore, a segmental re-ablation approach seems to be sufficient in the majority of patients (especially in patients treated with the second generation cryoballoon).

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.

Two-year safety and effectiveness of hybrid ablation versus catheter ablation in patients with non-paroxysmal AF: mid-term results of the CEASE-AF trial

Abstract Background Hybrid Ablation for atrial fibrillation (AF) combines epicardial and endocardial ablation through a Heart Team approach to target durable, transmural isolation of the pulmonary veins (PV) and left atrial posterior wall (LAPW). While the primary efficacy endpoint at 12 months was met with a significant benefit increase for hybrid ablation, we now report the midterm durability of those results. Purpose To evaluate 24-months safety and effectiveness of Hybrid Ablation with left atrial appendage exclusion (LAAE) versus Catheter Ablation in patients with persistent AF/enlarged left atrium and longstanding persistent AF (LSPAF). Methods CEASE-AF is a prospective, multi-center, 2:1 randomized controlled trial. Eligible patients were 18-75 years of age, had symptomatic, drug-refractory persistent AF and enlarged left atrium (&amp;gt;4 cm) or LSPAF, and were undergoing a first ablation. Hybrid Ablation consisted of two stages: thoracoscopic epicardial radiofrequency (RF) ablation for PV and LAPW isolation and epicardial LAAE followed by endocardial ablation 91-180 days later. Catheter Ablation consisted of minimum PV isolation by endocardial RF ablation, and repeat ablation was allowed between 91-180 days. In both arms, additional lesions were permitted according to institutional practices. Effectiveness was freedom from AF/atrial flutter (AFL)/atrial tachycardia (AT) off anti-arrhythmic drugs (AAD) (except AADs not exceeding doses which previously failed) and was assessed through 48-h Holter monitoring reviewed by an independent core laboratory blinded to the study. Safety was major adverse events throughout the study, adjudicated by an independent Clinical Events Committee. Results There were 102 Hybrid Ablation and 52 Catheter Ablation patients; 26% were female, mean age was 60.7±7.9 years, mean LAD was 4.7±0.4 cm, and 19% had LSPAF with no differences between arms. The 12- and 24-month results are shown for comparison (Table). Through 24-months, effectiveness was 66.3% (63/95) in the Hybrid Arm and 33.3% (17/51) in the Catheter Arm (absolute difference 33.0% [95% CI 14.3%, 48.3%; p&amp;lt;0.001]). Major adverse event rates through 24-months were statistically similar at 10.8% (11/102) in the Hybrid Arm and 9.6% (5/52) in the Catheter Arm (p=1.0). Through 24-months, repeat ablations were performed in 7.4% (7/95) of the Hybrid Arm versus 37.3% (19/51) of the Catheter Arm (p&amp;lt;0.001), and cardioversions were performed in 14.7% (14/95) of the Hybrid Arm versus 29.4% (15/51) of the Catheter Arm (p=0.034) Conclusions: CEASE-AF demonstrated that superior effectiveness of Hybrid Ablation including LAAE versus Catheter Ablation was durable through 24-month follow-up, with 33% absolute improvement in freedom from AF/AFL/AT. Safety rates continued to be similar between arms. Three-year follow-up is ongoing.

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

Gastric hypomotility after adjunctive pulmonary vein and posterior wall isolation using cryoballoon in patients with atrial fibrillation: case control study

Abstract Background Pulmonary vein isolation (PVI) and concomitant electrical isolation of left atrial (LA) posterior wall (posterior wall box isolation [POBI]) using cryoballoon have mentioned as alternative ablation method for atrial fibrillation (AF). Gastric hypomotility (GH) is a possible complication of cryoballoon ablation (CBA); however, it remains unclear which factors are associated with GH during PVI plus POBI using cryoballoon. Objective We sought to investigate the clinical characteristics and intra-procedural parameters in AF patients with GH after PVI plus POBI using cryoballoon. Methods Forty-seven patients who underwent first-time CBA procedure for drug-refractory AF were enrolled. After the completion of ipsilateral superior and inferior PVI, cryoballoon was subsequently used to perform POBI; ablating in a segmental fashion for both superior and inferior portions of LA posterior wall. Intra-procedural luminal esophageal temperature (LET) monitoring, and postprocedural esophagogastroscopy within 72 hours were performed in all patients. In addition, intra-procedural parameters of CBA were comparatively evaluated between the patients with or without GH. Results Of overall enrolled patients (69.6 ± 9.6 years, 62% paroxysmal AF, CHA2DS2-VASc score 3.2 ± 1.7), GH were observed in 4 (8.6%) patients. Clinical characteristics were similar between the patients with and without GH, while the diameter of left inferior pulmonary vein ostium was significantly smaller in patients with GH compared with those without (15.0 ± 1.5mm vs. 18.8 ± 0.5mm; p=0.018). With regard to the intra-procedural parameters, minimum balloon temperatures at 30 seconds after CBA initiation during inferior portions of LA posterior wall, and minimum LET during POBI were significantly lower in patients with GH compared with those without (-43.3 ± 4.9°C vs. -37.2 ± 5.0°C; p=0.024, and 15.8 ± 1.0°C vs. 23.0 ± 6.0°C; p=0.022, respectively). The optimal cut-off values for prediction were -45°C (sensitivity 75%; specificity 92.5%), and 16.8°C (sensitivity 100%; specificity 85.4%), respectively. Conclusion Specific anatomical information and intra-procedural parameters aid identifying high-risk populations of GH after PVI plus POBI using cryoballoon.

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.

Micro-Costing Analysis for the Treatment of Atrial Fibrillation: An Economic Evaluation of the First Italian Experience of Same-Day Discharge Protocol for Cryoballoon Atrial Fibrillation Ablation.

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia, and its prevalence is expected to increase further due to the aging population, increasing prevalence of risk factors, improving detection methods, and broadening of catheter ablation indications. Along with limited healthcare resources and bed availability, these reasons led to the development of a same-day discharge (SDD) protocol. The aim of this study was to evaluate the health and economic impact of a routine adoption of same-day discharge after cryoballoon AF ablation. Methods: Consecutive patients with symptomatic and drug-refractory AF scheduled for first-time AF ablation were screened, and if deemed suitable, the SDD protocol was proposed and, if accepted, enrolled in the protocol. Results: A total of 324 patients were screened, and 118 were considered eligible for the SDD pathway. Fifty-two patients accepted the SDD pathway and were included in this study. The analysis showed that the variation in resource consumption associated with cryoablation in SDD is equal to EUR 739.85/patient. The analysis showed that the main cost driver for ordinary hospitalization was represented by the hospital stay, which was calculated to be 36% of the total cost. In total, there was a cost reduction of EUR 38.472 thanks to optimized AF patient management from the standard recovery setting to SDD. Conclusions: SDD after cryoballoon ablation of AF is feasible in selected patients with a standardized protocol.

Initial clinical experience with the balloon-in-basket pulsed field ablation system: acute results of the VOLT CE mark feasibility study.

Pulsed field ablation (PFA) for the treatment of atrial fibrillation (AF) potentially offers improved safety and procedural efficiencies compared with thermal ablation. Opportunities remain to improve effective circumferential lesion delivery, safety, and workflow of first-generation PFA systems. In this study, we aim to evaluate the initial clinical experience with a balloon-in-basket, 3D integrated PFA system with a purpose-built form factor for pulmonary vein (PV) isolation. The VOLT CE Mark Study is a pre-market, prospective, multi-centre, single-arm study to evaluate the safety and effectiveness of the Volt™ PFA system for the treatment of paroxysmal (PAF) or persistent AF (PersAF). Feasibility sub-study subjects underwent phrenic nerve evaluation, endoscopy, chest computed tomography, and cerebral magnetic resonance imaging. Study endpoints were the rate of primary serious adverse event within 7 days and acute procedural effectiveness. A total of 32 subjects (age 61.6 ± 9.6 years, 65.6% male, 84.4% PAF) were enrolled and treated in the feasibility sub-study and completed a 30-day follow-up. Acute effectiveness was achieved in 99.2% (127/128) of treated PVs (96.9% of subjects, 31/32) with 23.8 ± 4.2 PFA applications/subject. Procedure, fluoroscopy, LA dwell, and transpired ablation times were 124.6 ± 28.1, 19.8 ± 8.9, 53.0 ± 21.0, and 48.0 ± 19.9 min, respectively. Systematic assessments of initial safety revealed no phrenic nerve injury, pulmonary vein stenosis, or oesophageal lesions causally related to the PFA system and three subjects with silent cerebral lesions (9.4%). There were no primary serious adverse events. The initial clinical use of the Volt PFA System demonstrates acute safety and effectiveness in the treatment of symptomatic, drug refractory AF.

Left Atrium Volume Measured with Multislice Computed Tomography as a Prognostic Predictor for Atrial Fibrillation Catheter Ablation Outcomes.

Background: Current guidelines consider atrial fibrillation (AF) type as the prognostic factor for a recommendation of catheter ablation. We aimed to determine whether LA and LA appendage (LAA) volumes measured using multislice computed tomography (MSCT) were related to long-term outcomes in AF following radiofrequency catheter ablation (RFCA). Methods: We evaluated 152 consecutive patients with drug-refractory AF (median age, 55.8 ± 9.6 years), including 110 male patients, who underwent RFCA in a single center. All patients underwent MSCT imaging for anatomical assessment. The endpoint of this study was documented AF recurrence after RFCA. Results: The overall procedure success rate was 77.6% (n = 118) during a mean follow-up period of 12.6 months. The LA volume was significantly larger for those who experienced AF recurrence after RFCA than for the patients without recurrent AF after the procedure (153.8 ± 29.9 mL vs. 139.2 ± 34.1 mL, p = 0.025). However, LAA volumes were nearly equivalent between the patients with and without AF recurrence after RFCA (16.2 ± 6.3 mL and 14.7 ± 6.5 mL, respectively; p = 0.235). LA volume ≥ 153.2 mL was the optimal cutoff value for estimating AF recurrence after RFCA, with 94% sensitivity and 66% specificity. LA volume remained an independent predictor of both AF recurrence and permanent AF. Conclusions: LA volume as assessed by MSCT might be helpful for identifying patients likely to achieve successful AF ablation. LA volume ≥ 153.2 mL, but not LAA volume, showed good accuracy in predicting AF recurrence after RFCA.