Pulsed-field ablation for repeat procedures after failed prior thermal ablation for atrial fibrillation.

Background: Pulsed-field ablation (PFA) is a novel nonthermal ablation technology. Its potential value for repeat procedures after unsuccessful thermal ablation for atrial fibrillation has not been assessed. Objective: The purpose of this study was to summarize our initial experience with patients undergoing repeat procedures using PFA. Methods: Consecutive patients with arrhythmia recurrences after a prior thermal ablation undergoing a repeat procedure using a multipolar PFA catheter from May 2021 and December 2022 were included. After 3-dimensional electroanatomic mapping, reconnected pulmonary veins (PVs) were reisolated and veins with only ostial isolation wither ablated to widen antral PV isolation. Posterior wall ablation was performed if all PVs were durably isolated or in case of low-voltage areas on the posterior wall at the discretion of the operator. Patients underwent follow-up with 7-day Holter electrocardiography after 3, 6, and 12 months. Results: A total of 186 patients undergoing a repeat procedure using PFA were included. The median number of previous ablations was 1 (range 1-6). The prior ablation modality was radiofrequency in 129 patients (69.4%), cryoballoon in 51 (27.4%), and epicardial ablation in 6 (3.2%). At the beginning of the procedure, 258 of 744 PVs (35%) showed reconnections. Additional antral ablations were applied in 236 of 486 still isolated veins (49%). Posterior wall ablation was added in 125 patients (67%). Major complications occurred in 1 patient (transient ischemic attack 0.5%). Freedom from arrhythmia recurrence in Kaplan-Meier-analysis was 78% after 6 months and 54% after 12 months. Conclusion: PFA is a versatile and safe option for repeat procedures after failed prior thermal ablation.

Early recurrence of atrial tachyarrhythmia indicates pulmonary vein reconduction independent of blanking period duration in the RACE-AF trial.

INTRODUCTION: Atrial tachyarrhythmia recurrence during the blanking period (early ATA) after pulmonary vein isolation (PVI) is associated with an increased risk of later recurrence, but its relationship with pulmonary vein reconduction (PVR) is poorly understood. The objective of the present study was to evaluate the relationship between early ATA and PVR. Second, to provide data on the optimal blanking period by (a) evaluating how the predictive values of ATA for PVR are affected by blanking period duration, and (b) assessing the temporal development in atrial fibrillation (AF) burden. METHODS: In this RACE-AF substudy, 91 patients with paroxysmal AF undergoing PVI randomized to radiofrequency or cryoballoon ablation were included. All patients received an implantable cardiac monitor and underwent a protocol-mandated repeat procedure after 4-6 months for assessment of PVR. ATA ≥ 30 s. ≤ 90 days after PVI constituted early ATA. RESULTS: PVR was found in 37/54 (69%) patients with early ATA and in 11/37 (30%) patients without (p < .001). The positive predictive value of ATA for PVR was independent of blanking period duration (range 0-90 days). In both patients with and without PVR, AF burden was higher in the first month after PVI, but AF burden from the second month was similar to AF burden after the conventional blanking period. CONCLUSION: Early ATA indicates PVR, and the positive predictive value is independent of the blanking period duration. Altogether, the results of this study support substantially shortening the blanking period after PVI for paroxysmal AF.

Repeat ablation strategy for recurrent persistent atrial fibrillation: A propensity-matched score comparison between "2C3L" and "extensive ablation" approach.

BACKGROUND: Debates exist in the repeat ablation strategy for patients with recurrence presenting as persistent atrial fibrillation (AF) after initial persistent AF ablation. OBJECTIVE: To compare the outcome between the "2C3L" and "extensive ablation" approach in patients undergoing repeat procedures for recurrent persistent AF. METHODS: Propensity-score matching was performed in 196 patients with AF recurrence undergoing repeat ablation, and 79 patients treated with "2C3L" strategy were matched to 79 patients treated with "extensive ablation" strategy. The "2C3L" approach included pulmonary vein isolation, mitral isthmus, left atrial roof, and cavotricuspid isthmus ablation, while the "extensive ablation" strategy included extensive ablation of a variety of other targets aiming to terminate the AF. The primary outcome was freedom from any atrial tachyarrhythmia after 24-h ambulatory monitoring follow-up for 12 months. RESULTS: No statistically significant difference was found between the primary outcome between the "2C3L" and the "extensive ablation" group [70.9% vs. 69.6%, p = .862; 95% confidence interval (CI) -12.8 to 15.3], although the "extensive ablation" group had a significantly high proportion of AF termination (19.0% for "2C3L" vs. 41.8% for "extensive ablation" group, p = .002; 95% CI 8.5-35.9). And AF termination was not related to the primary outcome in multifactorial regression. At 40 ± 22 months after the repeat procedure, the primary outcome was also comparable (57.0 % for "2C3L" vs. 48.1% for "extensive ablation" group, p = .265; 95% CI -6.6 to 23.7). CONCLUSION: The outcome between the "2C3L" and "extensive ablation" approaches was comparable in patients undergoing repeat procedures for recurrent persistent AF.

Extremely late recurrences (≥3 years) of atrioventricular nodal reentrant tachycardia: Electrophysiological characteristics of the index and repeat ablation procedures.

BACKGROUND: Catheter ablation is an effective treatment for atrioventricular nodal reentrant tachycardia (AVNRT). However, the characteristics of extremely late (>3 years) recurrences of AVNRT after a successful initial ablation are not fully elucidated. We aimed to explore the electrophysiological characteristics of extremely late recurrences of AVNRT after a successful ablation. METHODS: From 1991 to 2018, 3311 patients (mean age: 48.7 ± 17.4 years; men: 1328 [40.1%]) who underwent catheter ablation for AVNRT were investigated. Baseline characteristics of the patients, recurrence status, and detailed electrophysiological parameters of the index and repeat ablation procedures were obtained for analysis. RESULTS: After a mean follow-up period of 129.5 ± 58.0 months, 65 (2.0%) patients underwent repeat ablation for recurrences of AVNRT, of whom 17 (0.5%) presented with extremely late recurrences. The incidence of transient AV block was significantly higher in patients with extremely late recurrences (5.9%) than in those without recurrences (1.9%) but lower than that in patients with recurrences within <3 years (12.5%, P < .001). In addition, among patients with extremely late recurrences of AVNRT, the atrial-His bundle interval was significantly longer (99.1 ± 23.4 vs. 76.5 ± 13.1 ms, P < .01) and the need for intravenous isoproterenol and/or atropine for the induction of AVNRT (88.2% vs. 47.1%, P = .03) was higher in the repeat ablation procedure than in the index ablation procedure. CONCLUSION: Recurrences of AVNRT can occur 3 years after a successful initial ablation. The electrophysiological features of the index and repeat ablation procedures differed between patients with extremely late recurrences of AVNRT and those with recurrences within <3 years.

High-sensitivity cardiac Troponin T delta concentration after repeat pulmonary vein isolation.

INTRODUCTION: Difference between high-sensitivity cardiac troponin T concentrations (hs-cTnT) before and after ablation procedure (delta concentration) reflects the amount of myocardial injury. The aim of the study was to investigate hs-cTnT prognostic power for predicting atrial fibrillation (AF) recurrence after repeat pulmonary vein isolation (PVI) procedure. MATERIALS AND METHODS: Consecutive patients with paroxysmal AF undergoing repeat PVI using a focal radiofrequency catheter were included in the study. Hs-cTnT was measured before and 18-24 hours after the procedure. Standardized 3, 6 and 12-month follow-up was performed. Cox-regression analysis was used to identify predictors of AF recurrence. RESULTS: A total of 105 patients undergoing repeat PVI were analysed (24% female, median age 61 years). Median (interquartile range) hs-cTnT delta after repeat PVI was 283 (127 - 489) ng/L. After a median follow-up of 12 months, AF recurred in 24 (23%) patients. A weak linear relationship between the total radiofrequency energy delivery time and delta hs-cTnT was observed (Pearson R2 = 0.31, P = 0.030). Delta Hs-cTnT was not identified as a significant long-term predictor of AF recurrence after repeated PVI (P = 0.920). CONCLUSION: This was the first study evaluating the prognostic power of delta hs-cTnT in predicting AF recurrence after repeat PVI. Delta hs-cTnT does not predict AF recurrence after repeat PVI procedures. Systematic measurement of hs-cTnT after repeat PVI does not add information relevant to outcome.

Repeat procedure is a new independent predictor of complications of atrial fibrillation ablation.

AIMS: Atrial fibrillation (AF) ablation has made huge progress with respect to innovation, efficacy, and safety, however, complications are still present. Recent studies examined various predictors of complications. However, limited data exist regarding the role of a repeat procedure. Our aim was the prospective evaluation of the incidence and predictors of complications related to AF ablation procedures in consecutive patients, including repeat procedures. METHODS AND RESULTS: All ablation procedures for AF between January 2013 and December 2015 were analysed in our electrophysiology laboratory. During the study period 1243 procedures were analysed [394 female, median age 62 (55-69)]. Overall complication rate was 6.84%, major complication rate was 2.82%. Major complications were the following: 18 pericardial tamponades; 5 pseudoaneurysms; 1 arteriovenous fistula; 6 thromboembolic cerebrovascular events; 3 pulmonary vein stenosis; and 2 atrioventricular blocks. No atrio-oesophageal fistula or procedure related death occurred. Univariate analysis for overall complications showed that age ≥ 65 years (P = 0.0231), female gender (P = 0.0438), hypertension (P = 0.0488), CHA2DS2-VASc score ≥ 2 (P = 0.0156), and previous AF ablation procedure (P < 0.0001) is associated with higher risk for adverse events. Multivariate analysis showed that the only independent predictor of overall complications was previous AF ablation procedure (P < 0.0001). Similarly, the only predictor of major complications was previous AF ablation procedure (P < 0.0001). CONCLUSION: Incidence of complications associated with AF ablation in our high volume electrophysiology laboratory is similar to other cohorts. The only independent predictor of complications was previous AF ablation procedure in our series.

Predictors and outcomes of patients requiring repeat transvenous lead extraction of pacemaker and defibrillator leads.

BACKGROUND: A proportion of patients who undergo an initial lead extraction procedure will require a second, repeat extraction. Data regarding this clinical entity are scarce and neither the predisposing risk factors for, nor outcomes from, these procedures have been described previously. We sought to determine the incidence, risk factors, and outcomes of repeat lead extraction. METHODS: A database of extraction procedures from 2001 to 2015 was analyzed. Repeat extraction procedures were identified and the indication for extraction was dichotomized into infection and lead-related problems. Univariate and multivariate analyses were performed to identify predictors of repeat extraction. RESULTS: 807 extraction procedures were identified in 755 patients of whom 6% required a repeat extraction. At multivariate analysis, only suffering a major complication at the initial extraction procedure (odds ratio [OR] 21.5, 95% confidence interval [CI] 2.69-171.92; P < 0.01), complexity of device (cardiac resynchronization devices/implantable cardioverter defibrillators) (OR 2.58, 95% CI 1.2-5.2; P = 0.01), and age (OR 1.02 per year, 95% CI 1.0-1.4; P  =  0.03) were significant predictors of repeat extraction. When repeat extraction was required for infection there was a significant increase in mortality compared with those who did not require a second procedure (36% vs 23%; P  =  0.02). CONCLUSIONS: Repeat lead extraction is required in 6% of cases. Complexity of device, age at extraction, and a major complication at the first extraction were predictors of repeat extraction. Mortality is significantly increased where the repeat procedure is for infection. Clinicians should alert patients to the potential need for further extraction and the increased risks of repeat procedures when indicated for infection.

Long-term outcome of catheter ablation for left posterior fascicular ventricular tachycardia with the development of left posterior fascicular block and characteristics of repeat procedures.

OBJECTIVE: The present study aimed to retrospectively investigate long-term clinical outcomes of patients undergoing catheter ablation of left posterior fascicular ventricular tachycardia (LPF-VT) with the development of left posterior fascicular block (LPF block) and characteristics of repeat procedures. METHODS AND RESULTS: A total of 195 patients (mean age 29.76±1.03years, 16.4% females) who underwent catheter ablation for LPF-VT were consecutively enrolled. The earliest ventricular potential with a single fused Purkinje potential (PP) during VT and the PP located in the inferior-apical or mid-apical septum during SR were targeted for linear ablation. The endpoint of the procedure was noninducible VT and development of new-onset LPF block. Follow-up with clinic visits or telephonic interviews, electrocardiogram (ECG), or Holter monitoring was performed after the procedure. With a median follow-up of 85 (18,181) months, 20 patients were censored and 152 of 175 (86.86%) patients had long-term freedom from VT after a single procedure. No statistical difference in the outcome of catheter ablation of LPF-VT was found between inducible and non-inducible groups (P=0.89). Twenty-three patients exhibited recurrent LPF-VT. Seven of 23 patients developed new-onset left upper septal ventricular tachycardia that was successfully ablated. All the patients undergoing repeat procedures had freedom from VT. No procedural complications occurred. CONCLUSIONS: Ablation of LPF-VT using the development of LPF block as the endpoint is associated with a high procedural success rate. No difference in freedom from LPF-VT was found between inducible and non-inducible patients. New-onset LPF block recovery and non-early PP-QRS interval can be the predictors of LPF-VT repeat procedure.

Comparison of remote magnetic navigation ablation and manual ablation of idiopathic ventricular arrhythmia after failed manual ablation.

PURPOSE: Catheter ablation for idiopathic ventricular arrhythmia (VA) is effective and safe, but efficacy is frequently limited due to an epicardial origin and difficult anatomy. The remote magnetic navigation (RMN) catheter has a flexible catheter design allowing access to difficult anatomy. We describe the efficacy of the RMN for ablation of idiopathic VA after failed manual ablation. METHODS: Among 235 patients with idiopathic VA referred for catheter ablation, we identified 51 patients who were referred for repeat ablation after a failed manual ablation. We analyzed the clinical characteristics, including the successful ablation site and findings at electrophysiology study, in repeat procedures conducted using RMN as compared with manual ablation. Among these patients, 22 (43 %) underwent repeat ablation with the RMN and 29 (57 %) underwent repeat ablation with a manual ablation. RESULTS: Overall, successful ablation rate was significantly higher using RMN as compared with manual ablation (91 vs. 69 %, P = 0.02). Fluoroscopy time in the RMN was 17 ± 12 min as compared with 43 ± 18 min in the manual ablation (P = 0.009). Successful ablation rate in the posterior right ventricular outflow tract (RVOT) plus posterior-tricuspid annulus was higher with RMN as compared with manual ablation (92 vs. 50 %, P = 0.03). Neither groups exhibited any major complications. CONCLUSIONS: The RMN is more effective in selected patients with recurrent idiopathic VA after failed manual ablation and is associated with less fluoroscopy time. The RMN catheters have a flexible design enabling them to access otherwise difficult anatomy including the posterior tricuspid annulus and posterior RVOT.

Same site submucosal tunneling for a repeat per oral endoscopic myotomy: A safe and feasible option.

Per oral endoscopic myotomy (POEM) is a novel endoscopic procedure for achalasia treatment. Due to its novelty and high success rates, a repeat procedure is usually not warranted, making the feasibility and safety of such approach unknown. We report the first case of a successful repeat POEM done at the same site of a previously uncompleted POEM. An 84-year-old female with type 2 achalasia presented for a POEM procedure. The procedure was aborted at the end of tunneling and before myotomy due to hypotension, which later resolved spontaneously. POEM was re-attempted at the same site of the original tunnel 1 year afterward, and surprisingly we didn't encounter any submucosal fibrosis. The procedure felt similar to a native POEM and a myotomy was performed uneventfully. Our case is the first to suggest that submucosal tunneling during a repeat POEM can be done at the same site. Hypotension during POEM is a rare complication that should be recognized as a potential result of tension capnothorax, it can however, be managed with close supportive care.

Characteristics of Clinical and Induced Ventricular Tachycardia Throughout Multiple Ablation Procedures.

BACKGROUND: Optimal procedure endpoints of catheter ablation for ventricular tachycardia (VT) are not defined and multiple repeat procedures are sometimes required. However, there are few studies to compare the details of repeat procedures to the initial procedure. The aim of this study is to compare the characteristics of clinical and induced VT throughout multiple procedures and clarify their relations. METHODS AND RESULTS: Of 425 consecutive patients with structural heart disease who underwent catheter VT ablation, second, third and fourth procedures were performed in 101, 23, and 5 patients, respectively. Of 227 VTs that were induced during the second procedure, 68 (30%) VTs had previously been induced at the first procedure. In multivariable analysis, identification of an exit/isthmus site (HR = 0.29, P = 0.047), early termination of VT during radiofrequency application (HR 0.11, P = 0.037) and elimination of target VT at the end of first procedure (HR = 0.43, P = 0.036) were independently associated with noninducibility of the same VT at the second procedure. Over the course of multiple procedures the mean VT cycle length gradually lengthened (381 ± 107, 413 ± 111, 460 ± 124, 507 ± 99 milliseconds in first, second, third, and fourth procedure, respectively, P < 0.001) and more induced VTs became mappable (32%, 40%, 62%, and 70% in first, second, third, and fourth procedure, respectively, P < 0.001). CONCLUSIONS: Identification and ablation of VT exit/isthmus, early termination of VT during radiofrequency application and elimination of targeted VT are associated with absence of that VT during a repeat procedure, and recurrences are then mostly due to new VTs or other VTs that were not induced at the first procedure.

Predictors of recurrence after a repeat ablation procedure for paroxysmal atrial fibrillation: role of left atrial enlargement.

AIMS: This study sought to explore the predictors of recurrence in patients with paroxysmal atrial fibrillation (AF) undergoing repeat catheter ablation, especially the impact of left atrial (LA) remodelling after the original procedure on the outcome of repeat procedure. METHODS AND RESULTS: Ninety-five patients undergoing repeat ablation were enrolled in this study. Repeat procedure endpoints were pulmonary vein isolation, linear block when linear ablation is performed, and non-inducibility of atrial tachyarrhythmia by burst pacing. Patients with LA enlargement between the pre-original procedure and pre-repeat procedure were categorized as Group 1 (35 patients), while individuals with no change or decrease of LA diameter were categorized as Group 2 (60 patients). The mean duration from the original procedure to the repeat procedure was 12 months (1-40 months). After 29.6 ± 20.5 (3-73) months follow-up from the repeat procedure, 33 patients experienced recurrence (34.7%). The recurrence rate was significantly higher in Group 1 than in Group 2 (51.4 VS. 25.0%, P = 0.017). In univariate analysis, LA remodelling was the only predictor of recurrence. In multivariate analysis, after adjustment for age and LA diameter, Group 1 had a greater risk of recurrence after the repeat procedure (hazard ratio = 2.22, 95% confidence interval: 1.02-4.81, P = 0.043). CONCLUSIONS: Left atrial enlargement after undergoing the original catheter ablation of paroxysmal AF was an independent risk factor of recurrence after repeat ablation.