Atrial Arrhythmia Recurrence Research Articles

La identificación subjetiva y ablación de impulsores auriculares mejora el control del ritmo en la fibrilación auricular persistente. Estudio CHAOS-AF

Introduction and objectivesThe optimal approach for persistent atrial fibrillation (AF) ablation remains unknown. In patients with persistent AF, we compared an ablation strategy based on pulmonary vein isolation (PVI) plus ablation of drivers (PVI+D), with a conventional PVI-only approach performed in a 1:1 propensity score-matched cohort. MethodsDrivers were subjectively identified using conventional high-density mapping catheters (IntellaMap ORION, PentaRay NAV or Advisor HD Grid), without dedicated software, as fractionated continuous or quasicontinuous electrograms on 1 to 2 adjacent bipoles, which were ablated first; and as sites with spatiotemporal dispersion (the entire cycle length comprised within the mapping catheter) plus noncontinuous fractionation, which were only targeted in patients without fractionated continuous electrograms, or without AF conversion after ablation of fractionated continuous electrograms. Ablation included PVI plus focal or linear ablation targeting drivers. ResultsA total of 50 patients were included in each group (61±10 years, 25% women). Fractionated continuous electrograms were found and ablated in 21 patients from the PVI+D group (42%), leading to AF conversion in 7 patients. In the remaining 43 patients, 143 sites with spatiotemporal dispersion plus noncontinuous fractionation were targeted. Globally, AF conversion was achieved in 21 patients (42%). The PVI+D group showed lower atrial arrhythmia recurrences at 1 year of follow-up (30.6% vs 48%; P=.048) and at the last follow-up (46% vs 72%; P=.013), and less progression to permanent AF (10% vs 40%; P=.001). ConclusionsSubjective identification and ablation of drivers, added to PVI, increased 1-year freedom from atrial arrhythmia and decreased long-term recurrences and progression to permanent AF.

Surgical Ablation for Atrial Fibrillation: Risk Factors for Recurrence and Long-Term Outcome

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Due to the insufficient efficacy of antiarrhythmic drugs and their adverse side effects, there has been considerable interest in the interventional treatment of AF, including both catheter ablation and surgical ablation. Surgical ablation or the maze procedure is a treatment option for patients with AF undergoing concomitant or isolated cardiac surgery. We performed a retrospective study of prospectively collected data to investigate short- and long-term outcomes of patients who underwent the surgical ablation of AF. Outcome variables included freedom from recurrent atrial arrhythmias and mortality at 1-, 3-, 5-, and 7-year follow-ups. We also identified risk factors for arrhythmia recurrence and mortality. Israel's largest university tertiary care center. The study population comprised 668 patients operated on between January 1, 2006, and June 30, 2022. All patient data were extracted from our departmental database. Concomitant or stand-alone surgical AF ablation. The mean duration of follow-up was 106 ± 66.7 months. Freedom from AF was 97.6% (n = 615) and mortality was 3% (n = 20) at the 1-year follow-up, 95.3% (n = 574) and 6.1% (n = 45) at 3 years, 90.1% (n = 396) and 9.1% (n = 61) at 5 years, and 77.5% (n = 308) and 10.8% (n = 72) at 7 years. According to logistic regression analysis, age and female sex determined the 7-year freedom from AF, and risk factors for 7-year mortality included diabetes mellitus, age, and valve surgery. Surgical ablation had a high success rate, with freedom from recurrent atrial arrhythmia at 1-, 3-, 5-, and 7-year follow-ups. Age and female sex were factors determining the 5- and 7-year recurrence of AF.

Analysis of the effectiveness of the latest 4th-generation cryoballoon catheters in pulmonary vein isolation using high-resolution mapping

BackgroundLong-term data showed that up to 27% of pulmonary veins are reconnected using cryoballoon ablation. This study aimed to evaluate the efficacy of the latest 4th-generation cryoballoon catheters using ultra high-resolution mapping. MethodsIn patients with atrial fibrillation, a standard pulmonary vein isolation (PVI) with the latest 4th-generation cryoballoon catheter (Arctic Front Advance PRO, Medtronic Minneapolis, USA) and the spiral mapping catheter (Achieve Advance, Medtronic, Minneapolis, MN, USA) was performed. Subsequently, high-resolution mapping was achieved using the novel multipolar grid mapping catheter (Advisor HD Grid SE, Abbott Laboratories, USA). Follow-up was obtained after 6 months by means of a 7-day Holter electrocardiogram. ResultsIn our study, acute PVI was successfully achieved in all 31 patients. The latest 4th-generation cryoballoon catheter is safe in the acute phase of PVI. Additional high-resolution mapping (mean points per map 21,001 ± 4911) using the multipolar grid mapping catheter enabled us to identify residual gaps only in the carina pulmonary vein region; therefore, no additional ablation was performed. Three of 31 patients (10%) presented with atrial arrhythmia recurrence always related with pulmonary vein reconnection; using high-resolution mapping had no additional benefit in identifying pulmonary veins in which reconnection will occur. ConclusionThe utility of additional high-density mapping, facilitated by the HD Grid catheter after PVI with the 4th-generation cryoballoon catheter do not substantiate a discernible advantage over conventional mapping methodologies, particularly, the spiral mapping catheter. Residual carinal conduction was observed in a substantial cohort of patients (48%), highlighting a persistent challenge in achieving complete electrical isolation.

First-in-human clinical series of a novel conformable large-lattice pulsed field ablation catheter for pulmonary vein isolation.

Pulsed field ablation (PFA) has significant advantages over conventional thermal ablation of atrial fibrillation (AF). This first-in-human, single-arm trial to treat paroxysmal AF (PAF) assessed the efficiency, safety, pulmonary vein isolation (PVI) durability and one-year clinical effectiveness of an 8 Fr, large-lattice, conformable single-shot PFA catheter together with a dedicated electroanatomical mapping system. After rendering the PV anatomy, the PFA catheter delivered monopolar, biphasic pulse trains (5-6 s per application; ∼4 applications per PV). Three waveforms were tested: PULSE1, PULSE2, and PULSE3. Follow-up included ECGs, Holters at 6 and 12 months, and symptomatic and scheduled transtelephonic monitoring. The primary and secondary efficacy endpoints were acute PVI and post-blanking atrial arrhythmia recurrence, respectively. Invasive remapping was conducted ∼75 days post-ablation. At three centres, PVI was performed by five operators in 85 patients using PULSE1 (n = 30), PULSE2 (n = 20), and PULSE3 (n = 35). Acute PVI was achieved in 100% of PVs using 3.9 ± 1.4 PFA applications per PV. Overall procedure, transpired ablation, PFA catheter dwell and fluoroscopy times were 56.5 ± 21.6, 10.0 ± 6.0, 19.1 ± 9.3, and 5.7 ± 3.9 min, respectively. No pre-defined primary safety events occurred. Upon remapping, PVI durability was 90% and 99% on a per-vein basis for the total and PULSE3 cohort, respectively. The Kaplan-Meier estimate of one-year freedom from atrial arrhythmias was 81.8% (95% CI 70.2-89.2%) for the total, and 100% (95% CI 80.6-100%) for the PULSE3 cohort. Pulmonary vein isolation (PVI) utilizing a conformable single-shot PFA catheter to treat PAF was efficient, safe, and effective, with durable lesions demonstrated upon remapping.

Meta-analysis of pulsed-field ablation versus cryoablation for atrial fibrillation.

The available data on the treatment strategy of pulsed field ablation (PFA) for patients with atrial fibrillation (AF) is limited. This study aims to provide a comparative analysis of the efficacy, safety, and procedural efficiency between PFA and cryoballoon ablation (CBA) for AF. We conducted a comprehensive search of the EMBASE, PubMed, Cochrane Library, and ClinicalTrials.gov databases to identify trials comparing PFA with CBA for AF from their inception until December 2023. The odds ratio (OR) and mean difference (MD), along with a 95% confidence interval (CI), were utilized as measures of treatment effect. The analysis included 15 eligible trials with a total enrollment of 1880 patients. No significant differences were found in recurrent atrial arrhythmia (OR 0.83, 95% CI 0.64, 1.07) or periprocedural complications (OR 0.78, 95% CI 0.46, 1.30) between the two ablation techniques examined in this study. However, the PFA technique demonstrated a significantly shorter procedure time (MD -7.17, 95% CI -13.60, -0.73), but a longer fluoroscopy time (MD 2.53, 95% CI 0.87, 4.19). Similarly, PFA was found to be significantly associated with a decreased incidence of phrenic nerve palsy (OR 0.20, 95% CI 0.07, 0.59), but an increased incidence of cardiac tamponade (OR 4.07, 95% CI 1.15, 14.39). Moreover, there was a significantly higher release of troponin with PFA compared to CBA (MD 470.28, 95% CI 18.89, 921.67), while the increase in S100 protein and heart rate was significantly lower with PFA than with CBA (MD -64.41, 95% CI -105.46, -17.36), (MD -8.76, 95% CI -15.12, -2.40). The utilization of PFA provides a safer, time-saving, and tissue-specific procedure compared to CBA, while maintaining comparable success rates. This has the potential to enhance procedural efficiency and optimize resource utilization in clinical practice. These findings underscore the feasibility and promise of PFA as an alternative technique for PVI in patients with AF.

Pentaspline Pulsed Field Ablation Catheter Versus Cryoballoon for Atrial Fibrillation Ablation: Results From a Prospective Comparative Study.

Cryoballoon ablation is currently the gold standard technique for single-shot pulmonary vein isolation (PVI). Pulsed field ablation (PFA) has recently emerged as an interesting nonthermal alternative energy for PVI. The purpose of our study was to evaluate the safety and long-term efficacy of PVI using the pentaspline PFA catheter in comparison to cryoballoon ablation. Between January 2021 and December 2022, we included all consecutive patients of our center in whom a first PVI-only procedure was performed using PFA or cryoballoon. The choice of the energy was based on patients' preference between general anesthesia (PFA) and local anesthesia (cryoballoon). The primary end point was freedom from documented atrial arrhythmia recurrence after a 3-month blanking period. A total of 301 patients (paroxysmal atrial fibrillation in 220 patients) underwent a first PVI procedure performed using PFA (n=151) or cryoballoon (n=150). Complete short-term PVI was obtained in 144 of 150 patients (96%) in the cryoballoon group and in all patients of the PFA group (P=0.01). Procedure duration was significantly longer in the cryoballoon group. Transient and persistent phrenic nerve injuries were observed in the cryoballoon group only (13/150 and 2/150, respectively). One-year freedom from atrial arrhythmia was significantly higher in the PFA group compared with the cryoballoon group (87.9% versus 77.7%; adjusted hazard ratio, 0.53 [95% CI, 0.30-0.96]; P=0.037). This prospective, comparative, real-life study suggested that PFA could overcome safety limitations of cryoballoon with optimal effectiveness. Randomized controlled studies are required to further investigate the potential superiority of PFA over cryoballoon.

Cryoballoon ablation for atrial fibrillation in South Africa: One-year outcome from the Cryo Global Registry

Background. Pulmonary vein isolation (PVI) with cryoballoon catheter ablation (CBA) is a well-established and widely adopted method for the treatment of patients with atrial fibrillation (AF) to prevent recurrences of AF. CBA adoption in South Africa (SA) and outcome data in SA patients are limited.Objectives. To evaluate real-world usage, safety and effectiveness of CBA in SA. Methods. In this sub-analysis of the Cryo Global Registry, 81 participants with paroxysmal AF (PAF) and persistent AF (PsAF) were enrolled between 2017 and 2021 across two private SA hospitals. Baseline characteristics, procedural characteristics, 12-month safety, effectiveness (atrial arrhythmia recurrence), healthcare utilisation (repeat ablation and all-cause hospitalisation), quality of life (QoL; measured by EQ-5D-3L) and predefined symptoms were reported on. Results. Participants in the SA cohort were a mean (standard deviation) of 60 (12) years old, 19 (23.5%) were female, and 48 (59.3%) presented with PAF. The overall presence of baseline comorbidities in the SA cohort was relatively low compared with the entire Cryo Global Registry cohort. The acute PVI success rate was high (98.8%). Two serious procedure-related adverse events occurred in 2 (2.5%) participants in the SA cohort. Freedom from arrhythmia recurrence was 97.4% (95% confidence interval (CI) 83.2 - 99.6%) in PAF and 78.4% (95% CI 58.1 - 89.7%) in persistent AF (p=0.035). Kaplan-Meier estimates for freedom from repeat ablations and all-cause hospitalisations were 97.0% (95% CI 88.4 - 99.2%) and 98.5% (95% CI 90.0 - 99.8%), respectively. Participants reported significant improvement in EQ-5D-3L index score and symptoms from baseline (0.90 (0.11)) - 12 months (0.97 (0.07), p<0.001). Conclusion. CBA standard-of-care procedures in SA resulted in a high clinical freedom from arrhythmia recurrence, with a low risk of safety events within 12 months post ablation. In addition, participants experienced an improvement in QoL and high freedom from healthcare utilisation at 12 months. The obtained results will be important for guiding clinical decisions around CBA in SA.

Impact of Atrial Fibrillation Triggers on Long-Term Outcomes of a Second Catheter Ablation of Nonparoxysmal Atrial Fibrillation.

Background: Catheter ablation (CA) of atrial fibrillation (AF) triggers, including non-pulmonary vein (PV) foci, contributes to improved procedural outcomes. However, the clinical significance of an AF trigger ablation during second CA procedures for nonparoxysmal AF is unknown. Methods and Results: We enrolled 94 patients with nonparoxysmal AF undergoing a second CA. Intracardiac cardioversion during AF using high-dose isoproterenol was performed to determine the presence or absence of AF triggers. PV re-isolations were performed if PV potentials recurred, and if AF triggers appeared from any non-PV sites, additional ablation was added to those sites. We investigated the incidence of atrial arrhythmia recurrence (AAR) >3 months post-CA. Of the 94 enrolled patients, AF triggers were identified in 65 (69.1%), and of those with AF triggers, successful elimination of the triggers was achieved in 47 patients (72.3%). Multivariate analysis revealed that no observed AF triggers were a significant predictor of AAR (hazard ratio [HR] 1.97, 95% confidence interval [CI] 1.21-3.46, P=0.019). In a subanalysis of the patients with AF triggers, multivariate analysis showed that unsuccessful trigger ablation was significantly associated with AAR (HR 5.84, 95% CI 2.79-12.22, P<0.01). Conclusions: Having no observed AF triggers during a second CA session significantly increased the risk of AAR, as did unsuccessful CA of AF triggers.

Quantitative comparison of the isolation lesions between conventional- and larger-sized visually guided laser balloon ablation.

The importance of a wider circumferential isolation of the pulmonary veins (PV), which includes a large portion of the left atrial posterior wall (LAPW), has been suggested in several studies. However, the extended isolation area using a larger inflated visually guided laser balloon (VGLB) ablation remains to be elucidated. Seventy-eight patients with atrial fibrillation (AF) who underwent VGLB ablation were enrolled in this prospective study. An electroanatomic map of the left atrium was obtained before and after PV isolation (PVI) using a conventional-sized VGLB. The isolation areas were extended by the largest-sized VGLB ablation and remapped in the same manner. After the ablation, isolation areas were calculated with CARTO-3 system.The one-year atrial arrhythmia (Ata) recurrence was assessed. RESULTS: The largest-sized VGLB ablation yielded statistically greater areas of isolation in left-sided PV antrum (PVA) (11.5 ± 2.3 cm2 vs. 15.9 ± 3.5 cm2, P < .001) and right-sided PVA (14.2 ± 3.3 cm2 vs. 20.6 ± 4.4 cm2, P < .001) than the conventional-sized VGLB. Further, non-ablated LAPW (12.3 ± 4.4 cm2 vs. 7.8 ± 3.9 cm2, P < .001) was significantly reduced after largest-sized VGLB ablation, compared to the conventional-sized VGLB ablation.The one-year Ata freedom was 83.7% in patients with paroxysmal AF and 96.4% in those with persistent AF. The largest-sized VGLB ablation technique can create a significantly wider isolation area of PVA and debulk a large amount of LAPW than the conventional-sized VGLB ablation.The one-year outcome was similarly high in paroxysmal and persistent AF.

Data-driven classification of left atrial morphology and its predictive impact on atrial fibrillation catheter ablation.

Various left atrial (LA) anatomical structures are correlated with postablative recurrence for atrial fibrillation (AF) patients. Comprehensively integrating anatomical structures, digitizing them, and implementing in-depth analysis, which may supply new insights, are needed. Thus, we aim to establish an interpretable model to identify AF patients' phenotypes according to LA anatomical morphology, using machine learning techniques. Five hundred and nine AF patients underwent first ablation treatment in three centers were included and were followed-up for postablative recurrent atrial arrhythmias. Data from 369 patients were regarded as training set, while data from another 140 patients, collected from different centers, were used as validation set. We manually measured 57 morphological parameters on enhanced computed tomography with three-dimensional reconstruction technique and implemented unsupervised learning accordingly. Three morphological groups were identified, with distinct prognosis according to Kaplan-Meier estimator (p < .001). Multivariable Cox model revealed that morphological grouping were independent predictors of 1-year recurrence (Group 1: HR = 3.00, 95% CI: 1.51-5.95, p = .002; Group 2: HR = 4.68, 95% CI: 2.40-9.11, p < .001; Group 3 as reference). Furthermore, external validation consistently demonstrated our findings. Our study illustrated the feasibility of employing unsupervised learning for the classification of LA morphology. By utilizing morphological grouping, we can effectively identify individuals at different risks of postablative recurrence and thereby assist in clinical decision-making.

Expedited loading with intravenous sotalol is safe and feasible—primary results of the Prospective Evaluation Analysis and Kinetics of IV Sotalol (PEAKS) Registry

BackgroundLoading of oral sotalol for atrial fibrillation requires 3 days, frequently in the hospital, to achieve steady state. The Food and Drug Administration approved loading with intravenous (IV) sotalol through model-informed development, without patient data. ObjectiveWe present results of the first multicenter evaluation of this recent labeling for IV sotalol. MethodsThe Prospective Evaluation Analysis and Kinetics of IV Sotalol (PEAKS) Registry was a multicenter observational registry of patients undergoing elective IV sotalol load for atrial arrhythmias. Outcomes, measured from hospital admission until first outpatient follow-up, included adverse arrhythmia events, efficacy, and length of stay. ResultsOf 167 consecutively enrolled patients, 23% were female; the median age was 68 (interquartile range, 61–74) years, and the median CHA2DS2-VASc score was 3 (interquartile range, 2–4). Overall, 99% were admitted for sotalol initiation (1% for dose escalation), with a target oral sotalol dose of either 80 mg twice daily (85 [51%]) or 120 mg twice daily (78 [47%]); 62 patients (37%) had an estimated creatinine clearance ≤90 mL/min. On presentation, 40% of patients were in sinus rhythm, whereas 26% underwent cardioversion before sotalol infusion. In 2 patients, sotalol infusion was stopped for bradycardia or hypotension. In 6 patients, sotalol was discontinued before discharge because of QTc prolongation (3), bradycardia (1), or recurrent atrial arrhythmia (2). The mean length of stay was 1.1 days, and 95% (n = 159) were discharged within 1 night. ConclusionIV sotalol loading is safe and feasible for atrial arrhythmias, with low rates of adverse events, and yields shorter hospitalizations. More data are needed on the minimal duration required for monitoring in the hospital.

Efficacy of dapagliflozin in improving arrhythmia-related outcomes after ablation for atrial fibrillation: a retrospective single-center study.

Atrial fibrillation (AF) is a widespread type of sustained arrhythmia that poses significant health risks. Catheter ablation is the preferred treatment; however, arrhythmia recurrence remains challenging. Sodium-glucose co-transporter 2 inhibitors, particularly dapagliflozin (DAPA), have exhibited cardiovascular benefits. However, to date, the influence of these inhibitors on AF post-ablation remains unclear. We analyzed the records of 272 patients who underwent catheter ablation for AF from January 2018 to December 2022. Patients were divided into the control (n = 199) and DAPA (n = 73) groups based on DAPA prescription post-ablation. The primary outcome was total atrial arrhythmia recurrence after a 3-month blanking period. The mean age was 72.19 ± 5.45years; 86.8% of the patients were men. At 18months post-ablation, 36.2% and 9.5% of the patients in the control and DAPA groups, respectively, reported atrial arrhythmia. Multivariate analysis revealed that DAPA use was associated with a significantly reduced risk of arrhythmia recurrence (adjusted hazard ratio [aHR]: 0.15, 95% confidence interval [CI]: 0.07-0.32, p < 0.001). After propensity score-matching (PSM) in 65 pairs, arrhythmia recurrence was lower in the DAPA group compared with the control (8.3% versus 30.8%, aHR: 0.17, 95% CI: 0.06-0.51, p = 0.002). Freedom from total arrhythmia recurrence was significantly higher in the DAPA group compared with the control group in both the overall and PSM population (log-rank test p < 0.01). DAPA administration post-ablation was associated with significantly reduced atrial arrhythmia recurrence rates, indicating its potential as an adjunct therapy for enhancing the success of AF ablation.

Pulmonary vein capture is a predictor for long-term success of stand-alone pulmonary vein isolation with cryoballoon ablation in patients with persistent atrial fibrillation.

The mechanisms of AF development and progression are still not completely understood. Despite the relative efficacy of ablation, the risk of AF recurrence is substantial, particularly in patients with persistent AF (perAF). At present we do not have any reliable intra-procedural electrophysiologic predictors of long-term success of AF ablation other than pulmonary vein isolation. We evaluated selected intraprocedural pulmonary vein characteristics that may be helpful in future guidance of persistent AF ablation. 390 consecutive procedures using cryoballoon for initial AF ablation were divided by clinical presentation (paroxysmal or persistent AF), and by pulmonary vein (PV) response to pacing after completion of ablation (discrete electrogram elicited with pacing-"PV capture" or not-"Control"). Patients were followed (median 20 months) for recurrent atrial arrhythmias as the primary end point of the study. PV capture was identified in 20.3% and 17.1% and patients with paroxysmal and persistent AF respectively (ns). In patients with persistent AF presence of PV capture was associated with significantly better outcomes compared to patients without PV capture (p < 0.001). In the group "persistent AF and PV capture", an initial strategy of PV isolation and reisolation of the PVs (without additional lesions) for patients with recurrent atrial arrhythmias resulted in 20/23 (87%) patients in sinus rhythm off antiarrhythmic medications at study completion. In patients with paroxysmal AF, PV capture was not associated with outcome benefits. Specific electrophysiologic characteristics of PV (PV capture cycle length: PVCCL) did not have an impact on AF recurrence, although 25% shortening of PVCCL was observed after 60 s periods of pacing at short cycle lengths. No background demographic patient characteristic differences were identified between patients with vs. without PV capture. The presence of PV capture was associated with better outcomes in patients with persistent AF. PV capture may identify those patients with persistent AF in whom cryoballoon PV isolation alone is sufficient as an initial ablation procedure and as the primary ablation strategy for recurrent AF.

Pulmonary Vein Isolation in Elderly Patients ≥ 75 Years: A Propensity Score-Matched Analysis With Focus on Differences Among Atrial Fibrillation Types

BackgroundAge is a major risk factor for development of atrial fibrillation (AF) and associated with increased recurrence rates in the setting of rhythm control. Current data tend to support catheter ablation in elderly patients, but uncertainties exist regarding efficacy and safety of ablation in elderly patients. MethodsThis was a prospective single-centre observational study with propensity score matching (PSM) to investigate the influence of age on efficacy and safety of cryoballoon ablation (CBA) stratified by age (< 75 years vs ≥ 75 years) and AF phenotype (paroxysmal vs persistent). Primary efficacy endpoint was recurrence of atrial arrhythmia after a 90-day blanking period. Safety endpoints were death, stroke, or procedure-associated complications. ResultsConsecutive patients (n = 953) underwent CBA for first-time AF ablation. Median follow-up was 18 months. By means of PSM, 268 matches were formed. At 1 year, primary efficacy endpoint occurred in 22.4% of young vs 33.2% of elderly patients, including both AF phenotypes (hazard ratio [HR], 0.65; 95% confidence interval [CI], 0.47-0.90; P = 0.01). AF relapse occurred in 19.7% of young vs 28.5% of elderly patients with paroxysmal (HR, 0.63; 95% CI, 0.40-0.99; P = 0.046) compared with 25.9% (30 of 116, young) vs 38.8% (45 of 116, elderly) patients with persistent AF (HR, 0.62; 95% CI, 0.39-0.97; P = 0.038). No difference was observed regarding the incidence of safety endpoints between young and elderly patients (P = 0.38). ConclusionsCBA is associated with higher recurrence rates in elderly (≥ 75 years) than in younger patients, with highest recurrence rates in elderly patients with persistent AF.

One-year outcomes of wide antral cryoballoon ablation guided by high-density mapping vs. conventional cryoballoon ablation for atrial fibrillation: a propensity score-matched study.

Pulmonary vein isolation with wide antral ablation leads to better clinical outcomes for the treatment of atrial fibrillation, but the isolation lesion is invisible in conventional cryoballoon ablation. In this study, we aim to investigate the efficacy of the wide pulmonary vein isolation technique that includes the intervenous carina region, guided by high-density mapping, compared with pulmonary vein isolation alone without the mapping system. We conducted a propensity score-matched comparison of 74 patients who underwent a wide cryoballoon ablation guided by high-density mapping (mapping group) and 74 controls who underwent conventional cryoballoon ablation in the same period (no-mapping group). The primary outcome was a clinical recurrence of documented atrial arrhythmias for >30 s during the 1-year follow-up. Of 74 patients in the mapping group, residual local potential in the pulmonary vein antrum was found in 30 (40.5%) patients, and additional cryothermal applications were performed to achieve a wide pulmonary vein isolation. Compared with the no-mapping group, the use of the mapping system in the mapping group was associated with a longer fluoroscopic time (26.97 ± 8.07 min vs. 23.76 ± 8.36 min, P = 0.023) and greater fluoroscopic exposure [339 (IQR181-586) mGy vs. 224 (IQR133-409) mGy, P = 0.012]. However, no significant differences between the two groups were found in terms of procedural duration and left atrial dwell time (104.10 ± 18.76 min vs. 102.45 ± 21.01 min, P = 0.619; 83.52 ± 17.01 min vs. 79.59 ± 17.96 min, P = 0.177). The rate of 12-month freedom from clinical atrial arrhythmia recurrence was 85.1% in the mapping group and 70.3% in the no-mapping group (log-rank P = 0.029). Voltage and pulmonary vein potential mapping after cryoballoon pulmonary vein isolation can identify residual potential in the pulmonary vein antrum, and additional cryoablation guided by mapping leads to improved freedom from atrial arrhythmias compared with conventional pulmonary vein isolation without the mapping system. ChiCTR2200064383.

Subjective identification and ablation of drivers improves rhythm control in patients with persistent atrial fibrillation. The CHAOS-AF study

Introduction and objectivesThe optimal approach for persistent atrial fibrillation (AF) ablation remains unknown. In patients with persistent AF, we compared an ablation strategy based on pulmonary vein isolation (PVI) plus ablation of drivers (PVI+D), with a conventional PVI-only approach performed in a 1:1 propensity score-matched cohort. MethodsDrivers were subjectively identified using conventional high-density mapping catheters (IntellaMap ORION, PentaRay NAV or Advisor HD Grid), without dedicated software, as fractionated continuous or quasicontinuous electrograms on 1 to 2 adjacent bipoles, which were ablated first; and as sites with spatiotemporal dispersion (the entire cycle length comprised within the mapping catheter) plus noncontinuous fractionation, which were only targeted in patients without fractionated continuous electrograms, or without AF conversion after ablation of fractionated continuous electrograms. Ablation included PVI plus focal or linear ablation targeting drivers. ResultsA total of 50 patients were included in each group (61±10 years, 25% women). Fractionated continuous electrograms were found and ablated in 21 patients from the PVI+D group (42%), leading to AF conversion in 7 patients. In the remaining 43 patients, 143 sites with spatiotemporal dispersion plus noncontinuous fractionation were targeted. Globally, AF conversion was achieved in 21 patients (42%). The PVI+D group showed lower atrial arrhythmia recurrences at 1 year of follow-up (30.6% vs 48%; P=.048) and at the last follow-up (46% vs 72%; P=.013), and less progression to permanent AF (10% vs 40%; P=.001). ConclusionsSubjective identification and ablation of drivers, added to PVI, increased 1-year freedom from atrial arrhythmia and decreased long-term recurrences and progression to permanent AF.

Understanding Lesion Creation Biophysics and Improved Lesion Assessment during Radiofrequency Catheter Ablation. The Perfect Combination to Achieve Durable Lesions in Atrial Fibrillation Ablation.

Atrial fibrillation (AF) is a prevalent arrhythmia, while pulmonary vein isolation (PVI) has become a cornerstone in its treatment. The creation of durable lesions is crucial for successful and long-lasting PVI, as inconsistent lesions lead to reconnections and recurrence after ablation. Various approaches have been developed to assess lesion quality and transmurality in vivo, acting as surrogates for improved lesion creation and long-term outcomes utilizing radiofrequency (RF) energy. This review manuscript examines the biophysics of lesion creation and different lesion assessment techniques that can be used daily in the electrophysiology laboratory when utilizing RF energy. These methods provide valuable insights into lesion effectiveness, facilitating optimized ablation procedures and reducing atrial arrhythmia recurrences. However, each approach has its limitations, and a combination of techniques is recommended for comprehensive lesion assessment during AF catheter ablation. Future advancements in imaging techniques, such as magnetic Resonance Imaging (MRI), optical coherence tomography, and photoacoustic imaging, hold promise in further enhancing lesion evaluation and guiding treatment strategies.

Left Atrial Low Voltage Areas Predicts Recurrence of Atrial Fibrillation after Catheter Ablation: A Meta-Analysis.

Low voltage areas (LVAs) on left atrial (LA) voltage mapping correlate with atrial fibrosis. However, there is no uniform standard for the definition of LVAs, or mapping techniques and mapping rhythms, so that the predictive value of left atrial LVAs for recurrence of atrial fibrillation (AF) is uncertain. This study aimed to explore the relationship between the presence of pre-ablation left atrial LVAs and the risk of recurrent AF after catheter ablation. The databases of PubMed, Embase, Web of science, Cochrane library, Scopus, Wanfang Datebase, China National Knowledge Infrastructure, China Biology Medicine and China Scientific Journal Datebase were searched from inception to 31 July 2023. Relevant studies regarding left atrial LVAs prior to ablation to predict postoperative recurrence of AF were identified and analyzed. The efficacy endpoints were defined as the recurrence of atrial arrhythmia lasting over 30 s. A total of 12 studies with 1070 patients were included. We found the presence of pre-ablation left atrial LVAs correlated with the risk of recurrent AF after ablation (hazard ratio (HR) = 2.87, 95% confidence interval (CI): 2.33-3.52). The presence of pre-ablation left atrial LVAs can predict the risk of recurrent AF after ablation both in the follow-up duration ≤12 months group and follow-up duration >12 months group (follow-up duration ≤12 months: HR = 2.93, 95% CI: 2.20-3.90; follow-up duration >12 months: HR = 2.80, 95% CI: 2.09-3.77). The presence of pre-ablation left atrial LVAs correlated with the risk of recurrent AF after ablation in paroxysmal AF (HR = 2.89, 95% CI: 1.97-4.24). The presence of pre-ablation left atrial LVAs correlate with the risk of recurrent AF after catheter ablation.

Analysis of the endocardial stage of treatment of tachyarhythmias after open interventions for atrial fibrillation. Experience of one center

AIM: To study EFI parameters and features of recurrent atrial tachyarrhythmias in patients who underwent surgical correction of AF.&#x0D; MATERIALS AND METHODS: from January 2013 to December 2021, 447 combined interventions were performed to eliminate AF using the labyrinth-3 and left atrial labyrinth techniques with correction of CHD (congenital heart disease) and/or coronary artery disease.&#x0D; Rhythm disturbances were detected in 57 (12.7%) patients at various follow-up periods. Endovascular interventions were performed in 39 patients. The average follow-up period after the endocardial stage was 34.37 (standard deviation 24.32) months. The median age of patients was 64 (58–67) years, 21 (54%) were men. The patients were divided into 2 groups: group 1 — after the classic biatrial (BA) labyrinth-3 — 23 (59%) patients, group 2 — after the left-atrial variant (LA) labyrinth-3 — 16 (41%) patients.&#x0D; At the endocardial stage, electrophysiological studies (EFI) were performed to clarify the mechanism of arrhythmia, and ablation eliminated tachyarrhythmia. EFI protocol: revision of the pulmonary veins, determination of the isolation of the posterior wall of the LA assessment of atrial arrhythmia, elimination of arrhythmia, control induction of arrhythmia after ablation. After repeated intervention, patients were observed in the operating clinic every 3 months.&#x0D; RESULTS: After the endocardial stage, a regular rhythm was determined in 19 (82.6%) patients of the BA group, 13 (92.9%) patients of the LA group (p = 0.914). Relapses in the form of AF were noted in 5 patients (4 — group 1 and 1 — group 2) group (p = 0.306) All relapses of tachyarrhythmia with an irregular cycle (AF) were detected in patients with AF before the endovascular stage In both groups, there were cases of restoration of conduction in the pulmonary veins — 10 (43.5%) patients after BA ablation and 1 (5.3%) patient after LA ablation. There are no recurrences of atrial arrhythmia after ablation of atrial flutter (arrhythmia with a stable cycle).&#x0D; CONCLUSION: The endocardial stage is highly effective and demonstrates subsequent freedom from atrial arrhythmia in patients who have tachycardia with a regular cycle after both methods of surgical ablation of AF. Recurrent tachyarrhythmia in the form of AF (irregular cycle) is associated with a low probability of maintaining a regular atrial rhythm after a repeated endocardial procedure, due to the presence of structural and electrophysiological changes in the atrial myocardium.

The efficacy and safety of cryoballoon atrial fibrillation ablation in patients with heart failure: A systematic review and meta-analysis

IntroductionWhile atrial fibrillation (AF) ablation has proven beneficial for heart failure (HF) patients, most reports were performed with radiofrequency ablation. We aimed to evaluate the efficacy and safety of cryoballoon AF ablation in patients with HFrEF. MethodWe comprehensively searched the databases of MEDLINE, EMBASE, and Cochrane database from inception to December 2022. Studies that reported the outcomes of freedom from atrial arrhythmia, complications, NYHA functional class (NYHA FC), and left ventricular ejection fraction (LVEF) after Cryoballoon AF ablation in HF patients were included. Data from each study were combined with a random-effects model. ResultA total of 9 studies observational studies with 1414 HF patients were included. Five studies had only HF with reduced ejection fraction (HFrEF), 1 study with HF with preserved ejection fraction (HFpEF), and others with mixed HF types. Freedom from AA in HFrEF at 12 months was 64% (95% CI 56–71%, I2 58%). There was a significant improvement of LVEF in these patients with a standard mean difference of 13% (95% CI 8.6–17.5%, I2 99% P < 0.001. The complication rate in HFrEF group was 6% (95% CI 4–10%, I2 0%). The risk of recurrence of atrial arrhythmia was not significantly different between HF and no HF patients (RR 1.34, 95% CI 0.8–2.23, I2 76%). ConclusionCryoballoon AF ablation is effective in HFrEF patients comparable to radiofrequency ablation. The complication rate was low.