BACKGROUND: Pulsed field ablation (PFA) is a novel, myocardial-selective, non-thermal ablation modality used to target cardiac arrhythmias. Although prompt EGM signal disappearance is observed immediately after PFA application in the pulmonary veins, whether this finding results in adequate transmural lesions is unknown.
OBJECTIVE: If application repetition and catheter-tissue contact impact on lesion formation during PFA.
METHODS: A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact-force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 hours in the vegetal model and over 6 hours in the porcine model.
RESULTS: Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 mm and 4.4 ± 1.3 mm, respectively (p =0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0±0.9 mm with no contact Vs. 5.4±1.4 mm with 30 g of force; p=.0001).
CONCLUSIONS: PFA delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA ablation are more related to PFA biophysics than mere EGM attenuation.

UNASSIGNED: Currently, two types of cryoballoon (CB) systems are available for catheter ablation of atrial fibrillation (AF). Since the POLARx (Boston Scientific) is softer during freezing than the Arctic Front Advance Pro (AFA-Pro; Medtronic), it tends to go more deeply into the pulmonary vein (PV), risking PV stenosis.
UNASSIGNED: Ninety-one patients underwent initial CB ablation for paroxysmal AF (AFA-Pro 56; POLARx 35). Twenty-six from each group were extracted using propensity score matching. The PV cross-sectional area (PVA) was measured by tracing the area within the PV plane at 5-mm intervals from the PV ostium in a distal direction for 20 mm or to the bifurcation in each PV. The PVA was compared before and 3 months after ablation.
UNASSIGNED: Time to balloon temperatures of -30 and - 40°C was significantly shorter and the nadir temperature was significantly lower with POLARx than with AFA-Pro. In the left inferior (LI) PV and right superior (RS) PV, the freezing balloon position was significantly deeper in POLARx than in AFA-pro. The freezing position in RSPV with mild to moderate narrowing was deeper than those without (10.2 ± 3.3 mm vs. 8.2 ± 1.8 mm, p = .01). In RSPV, the reduction of PVA tended to be greater with the POLARx than with the AFA-Pro (26.1% ± 14.1% vs. 19.9% ± 10.3%, p = .07).
UNASSIGNED: There was no significant difference in the incidence of PV stenosis between POLARx and AFA-Pro. However, if POLARx goes deep into the PVs, we will still have to be careful.

暂无摘要。

UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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.
UNASSIGNED: 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.

BACKGROUND: Cryoballoon ablation for treatment of atrial fibrillation (AF) reduces procedure times, but limited data is available about its impact on electrophysiology (EP) lab efficiency in Central and Eastern Europe (CEE). Using CEE-specific procedure data, the present study modeled cryoballoon ablation procedures on EP lab resource consumption to improve efficiency.
METHODS: A discrete event simulation model was developed to assess EP efficiency with cryoballoon ablation. Model inputs were taken from CEE sites within the Cryo Global Registry, namely Czech Republic, Hungary, Poland, Serbia, and Slovakia. The main endpoints were percentage of days that resulted in overtime and percentage of days with time for one extra simple EP procedure. Use of the \'figure of 8\' (Fo8) closure technique to reduce procedure time was also examined.
RESULTS: The mean lab occupancy time across all CEE sites was 133 ± 47 minutes (min: 104 minutes, max:181 minutes). Cryoballoon ablation in the base-case scenario resulted in 14.6% of days with overtime and 64.8% of days with time for an extra simple EP procedure. Use of the Fo8 closure technique enhanced these values to 5.5% and 85.3%, respectively. Model endpoints were most sensitive to changes in lab occupancy times and overtime start time.
CONCLUSIONS: In this CEE-specific analysis of EP lab efficiency it was found that 3 cryoballoon ablation procedures could be performed in 1 lab day, leaving time for a 4th simple EP procedure on most days. As such, use cryoballoon ablation for PVI is an effective way to improve EP lab efficiency.

BACKGROUND: The long-term success rate of pulmonary vein isolation (PVI) is suboptimal due to the presence of non-pulmonary vein (PV) foci that can trigger atrial fibrillation (AF) in up to 11%. Among non-PV triggers, the superior vena cava (SVC) is a major site of origin of ectopic beats initiating AF.
OBJECTIVE: To compare data from randomized controlled trials (RCTs) assessing PVI + empiric SVC isolation (SVCI) versus PVI alone in terms of AF recurrence, procedure-related complications, and fluoroscopic and procedural times.
METHODS: A search of online scientific libraries (from inception to April 1, 2024) was performed. Four RCTs were considered eligible for the meta-analysis totaling 600 patients of whom 287 receiving PVI + SVCI and 313 receiving PVI alone.
RESULTS: In the overall population, SVCI + PVI was associated with a non-significant reduction of AF recurrence at follow-up (0.66 [0.43;1.00], p = 0.05, I2 0%). In patients with paroxysmal AF (PAF), a significant reduction of AF recurrence was related to SVCI + PVI (11.7%) as compared to PVI alone (19.9%) (0.54 [0.32;0.92], p = 0.02, I2 0%). No statistical differences were found among the groups in terms of fluoroscopic (3.31 [- 0.8;7.41], p = 0.11, I2 = 91%), procedural times (5.69 [- 9.78;21.16], p = 0.47, I2 = 81%), and complications (1.06 [0.33;3.44], p = 0.92, I2 = 0%).
CONCLUSIONS: The addition of SVCI to PVI in patients in PAF is associated with a significant lower rate of AF recurrence at follow-up, without increasing complication rates and procedural and fluoroscopy times.

UNASSIGNED: Single-shot devices are increasingly used for pulmonary vein isolation (PVI) in atrial fibrillation (AF). The Arctic Front cryoballoon is the most frequently used single-shot technology. A recently developed novel pulsed field ablation (PFA) device (FARAPULSE) has been introduced with the aim to improve procedural safety and efficacy.
UNASSIGNED: This study will compare the novel FARAPULSE PFA device and the Arctic Front cryoballoon for first PVI in patients with symptomatic paroxysmal AF.
UNASSIGNED: SINGLE SHOT CHAMPION is a multicenter, randomized controlled trial with blinded endpoint adjudication by an independent clinical events committee. Overall, 210 patients with paroxysmal AF undergoing their PVI are randomized 1:1 between PFA and cryoballoon ablation. Continuous rhythm monitoring with an implantable cardiac monitor is performed in all patients.
UNASSIGNED: The primary endpoint is time to first recurrence of any atrial tachyarrhythmia (AF and/or organized atrial tachyarrhythmia) lasting ≥120 seconds and identified by the implantable cardiac monitor within 91 and 365 days postablation. The composite procedural safety endpoint includes cardiac tamponade requiring drainage, persistent phrenic nerve palsy, vascular complications requiring intervention, stroke/transient ischemic attack, atrioesophageal fistula, and death occurring during or up to 30 days after the procedure. Key secondary endpoints include (1) increase in high-sensitivity troponin on day 1 postablation, (2) analysis of postablation 3-dimensional electroanatomic mapping (first 25 patients per study group), (3) AF burden, and (4) quality-of-life changes.
UNASSIGNED: SINGLE SHOT CHAMPION will evaluate the efficacy and safety of PVI using the novel FARAPULSE PFA for patients with symptomatic paroxysmal AF.

BACKGROUND: Despite improvement in treatment strategies for atrial fibrillation (AF), a significant proportion of patients still experience recurrence after ablation. This study aims to propose a novel algorithm based on Transformer using surface electrocardiogram (ECG) signals and clinical features can predict AF recurrence.
METHODS: Between October 2018 to December 2021, patients who underwent index radiofrequency ablation for AF with at least one standard 10-second surface ECG during sinus rhythm were enrolled. An end-to-end deep learning framework based on Transformer and a fusion module was used to predict AF recurrence using ECG and clinical features. Model performance was evaluated using areas under the receiver operating characteristic curve (AUROC), sensitivity, specificity, accuracy and F1-score.
RESULTS: A total of 920 patients (median age 61 [IQR 14] years, 66.3% male) were included. After a median follow-up of 24 months, 253 patients (27.5%) experienced AF recurrence. A single deep learning enabled ECG signals identified AF recurrence with an AUROC of 0.769, sensitivity of 75.5%, specificity of 61.1%, F1 score of 55.6% and overall accuracy of 65.2%. Combining ECG signals and clinical features increased the AUROC to 0.899, sensitivity to 81.1%, specificity to 81.7%, F1 score to 71.7%, and overall accuracy to 81.5%.
CONCLUSIONS: The Transformer algorithm demonstrated excellent performance in predicting AF recurrence. Integrating ECG and clinical features enhanced the models\' performance and may help identify patients at low risk for AF recurrence after index ablation.

BACKGROUND: High-frequency low-tidal-volume (HFLTV) ventilation during radiofrequency catheter ablation (RFCA) for paroxysmal atrial fibrillation (PAF) has been shown to be superior to standard ventilation (SV) in terms of procedural efficiency, acute and long-term clinical outcomes. Our study aimed to compare ablation lesions characteristics utilizing HFLTV ventilation versus SV during RFCA of PAF.
METHODS: A retrospective analysis was conducted on patients who underwent pulmonary vein isolation (PVI) for PAF between August 2022 and March 2023, using high-power short-duration ablation. Thirty-five patients underwent RFCA with HFLTV ventilation and were matched with another cohort of 35 patients who underwent RFCA with SV. Parameters including ablation duration, contact force (CF), impedance drop, and ablation index were extracted from the CARTONET database for each ablation lesion.
RESULTS: A total of 70 patients were included (HFLTV = 35/2484 lesions, SV = 35/2830 lesions) in the analysis. There were no differences in baseline characteristics between the groups. While targeting the same ablation index, the HFLTV ventilation group demonstrated shorter average ablation duration per lesion (12.3 ± 5.0 vs. 15.4 ± 8.4 s, p < .001), higher average CF (17.0 ± 8.5 vs. 10.5 ± 4.6 g, p < .001), and greater impedance reduction (9.5 ± 4.6 vs. 7.7 ± 4.1 ohms, p < .001). HFLTV ventilation group also demonstrated shorter total procedural time (61.3 ± 25.5 vs. 90.8 ± 22.8 min, p < .001), ablation time (40.5 ± 18.6 vs. 65.8 ± 22.5 min, p < .001), and RF time (15.3 ± 4.8 vs. 22.9 ± 9.7 min, p < .001).
CONCLUSIONS: HFLTV ventilation during PVI for PAF was associated with improved ablation lesion parameters and procedural efficiency compared to SV.

BACKGROUND: There remains an imperative need to accurately map the left atrium in the setting of atrial fibrillation. While the pulmonary vein segmental ostial isolation plays a significant role in atrial fibrillation, clinical attempts to selectively ablate near the pulmonary vein myocardial sleeves have demonstrated a higher recurrence rate of arrhythmia given less precise mapping modalities. However, novel omnipolar mapping technology coupled with Advisor™ HD Grid Mapping Catheter may provide an advantageous profile to map and selectively ablate near the myocardial sleeves.
METHODS: This retrospective cohort underwent ablation targeting the pulmonary vein myocardial sleeves with the use of omnipolar mapping technology and later wide area circumferential ablation (WACA) was performed.
RESULTS: The findings of this study demonstrated a few number of lesions were required to achieve all PVI targeting PVMS at 36 (95% CI 32-41) compared to WACA at 81 (95% CI 73-90). PVMS radiofrequency time was shorter at 314 s (95% CI 278-350 s) compared to 799 s (95% CI 692-906 s) for WACA. Mean procedure time to complete PVMS was 59 min (95% CI 53-65) and to complete WACA was 90 min (95% CI 80-100).
CONCLUSIONS: Precision ablation near PVMS coupled with omnipolar technology may provide a superior profile in reducing procedure time and number of ablative lesions compared to WACA in the setting of atrial fibrillation with possible similar results. Future investigation using randomized controlled trials can help further support these findings.