Explore the vast range of titles available.

IntroductionLeft atrial perimitral flutter is a common late complication of atrial fibrillation ablation. Repeat ablation with a posterolateral mitral isthmus line to eliminate the flutter circuit has proven technically challenging, leading some to opt for anteroseptal line ablation as an alternative. A significant issue with the latter approach is the emergence of a biatrial flutter using the right atrial septum via epicardial connections to bypass the line of block and allow continued flutter propagation (image 1). In this case series we present our experience of biatrial flutter in patients with previous anteroseptal left atrial ablation.MethodsWe reviewed all cases of biatrial flutter treated at our institution from January 2017 to July 2024.ResultsFour cases of biatrial flutter were identified. Clinical and procedural characteristics are listed in table 1. All patients were male and had undergone prior pulmonary vein isolation and anteroseptal line. Ablation at sites of interatrial conduction successfully terminated biatrial flutter in 3 out of 4 cases. The remaining case had an unsuccessful ablation and was cardioverted to sinus rhythm.ConclusionBiatrial flutter is a potential complication following anteroseptal line formation for perimitral flutter, necessitating biatrial mapping for diagnosis. Ablation at interatrial connection sites where earliest activation is identified is a potentially effective treatment strategy.Abstract 60 Figure 1[Image Omitted. See PDF.]Abstract 60 Table 1 Case Age Sex Ablation prior to biatrial flutter Interatrial connections involved Ablation site Outcome 1 58 Male PVI, LAPWI, ASL BB, CS Superior RA septum, cavoatrial junction Successful 2 69 Male PVI, LARL, LAPWI, ASL, CTI, PLL BB (posterosuperior branch), CS High posterior RA Successful 3 75 Male CTI, ASL BB, CS Posteroseptal SVC Successful 4 70 Male PVI, ASL BB, CS Superior LA (close to BB insertion), PLL Unsuccessful (cardioverted) PVI = pulmonary vein isolation, LAPWI = left atrial posterior wall isolation, ASL = anteroseptal line, LARL = left atrial roof line, CTI = cavotricuspid isthmus, PLL = posterolateral line, BB = Bachmann’s bundle, CS = coronary sinus, RA = right atrium, SVC = superior vena cava

BackgroundThe use of pulse field ablation in pulmonary vein isolation for treating atrial fibrillation is becoming more widespread. This method may create larger, more uniform, and deeper lesions compared to other techniques. Consequently, it could lead to the formation of a narrow conductive isthmus on the posterior wall, potentially heightening the likelihood of arrhythmias.MethodsElectroanatomic mapping of the left atrium during coronary sinus pacing was performed before and after pulsefield ablation pulmonary vein isolation using the Carto electroanatomic mapping system and using a Pentaray mapping catheter. Electroanatomic maps were converted into an OpenEP format and analysed using EPWorkbench. The posterior wall conducting channel was measured as the distance between 0.5mV isolines atthree levels (roof, mid and inferior). Conducting channel width was defined as the average of these three measurements and also quantified as a proportion of the inter-vein distance. Conduction velocity within the posterior wall region was quantified pre- and post-ablation. (See image 1)ResultsAnalysis was completed in 35 patients (77% male, mean age 60.8 years, range 24–80 years). As expected the conduction channel width was significantly reduced post pulse fi eld ablation with the channel width approximately 38% of the pre-ablation width. (table 1)ConclusionsFollowing pulse field ablation pulmonary vein isolation there is a wide range of conducting channel widths remaining on the posterior wall, with conduction properties of these channels unchanged from pre-ablation. Further research is needed to identify whether a specific minimum channel width impacts conduction properties and increases the likelihood of atrial tachycardia in patients following pulse field ablation.Abstract 83 Table 1[Image Omitted. See PDF.]Abstract 83 Image 1[Image Omitted. See PDF.]

BackgroundEndobiliary radiofrequency ablation (EB-RFA) has emerged as a palliative treatment for malignant biliary strictures (MBSs); however, concerns about complications related to thermal injury remain. In this study, we evaluated the efficacy and safety of EB-RFA with a novel catheter for MBS.MethodsPatients with inoperable cancer causing MBS were randomly assigned to either the radiofrequency ablation (RFA) group or the non-RFA group. The RFA group underwent EB-RFA at the stricture site with a temperature-controlled catheter (ELRA™; STARmed Co., Goyang, Korea) followed by deployment of a self-expanding metal stent (SEMS). For the non-RFA group, only SEMS placement was performed. The duration of stent patency, overall survival (OS), and 30-day complication rate were evaluated. This trial was registered at ClinicalTrials.gov (number NCT02646514).ResultsA total of 48 patients were enrolled (24 in each group). During a median follow-up period of 135.0 days (RFA group) and 119.5 days (non-RFA group), the 90-day stent patency rate, median duration of stent patency, and median OS were not different between the groups (58.3% vs. 45.8% [P = 0.386], 132.0 days vs. 116.0 days [P = 0.440], and 244.0 days vs. 180.0 days [P = 0.281], respectively). In the RFA group, procedure-related complications including thermal injury-related complications, such as bile duct perforation or hemobilia, were not reported. The early complication (< 7 days) rates were not different between the groups (4.2% vs. 12.5%, P = 0.609), and there were no late complications (7–30 days) in both groups.ConclusionEB-RFA with a temperature-controlled catheter followed by SEMS placement for patients with inoperable MBS can be safe and feasible with acceptable biliary patency.

BackgroundAtrial fibrillation (AF) recurrence post catheter ablation can occur in up to 50% within 12 months of treatment. Previously, several novel scoring systems have been suggested, inclusive of CHADS2VASc, R2CHADS2, CHADS2 and APPLE score. Nevertheless, prediction of AF recurrence and subsequent readmission remains difficult.Methods and Results383 consecutive patients attended the Golden Jubilee National Hospital, Glasgow, to undertake cryoablation for AF. Average age 58 (± 13), 64% male, BMI 29 (± 4.7), 60% paroxysmal AF. Degrees of socioeconomic deprivation as per Scottish Index of Multiple Deprivations (SIMD) were recorded in deciles. Patients were followed up to at least 12 months post procedure. After initial 3-month blanking period, symptomatic recurrence of documented AF (not SVT/Atrial tachycardia/Flutter) requiring admission to hospital were observed in 86 patients (22.5%).Individual CHADS2VASc Score, R2CHADS2 (R for renal dysfunction), APPLE Score(one point for Age >65 years, Persistent AF, imPaired eGFR (<60 ml/min/1.73m2), Left atrial diameter ≥43 mm, left ventricular Ejection fraction <50%) were recorded and compared to Scottish Index of Multiple Deprivations (SIMD) using statistical methods to assess for AUC as per ROC Curve.In the current cohort of patients, previous scoring systems CHA2DS2-VASc score (AUC 0.5337 (95% CI 0.4336 – 0.6338, p = 0.287), R2CHADS2 score (AUC 0.5202 (95% CI 0.4201 – 0.6203, p = 0.874) and APPLE score (AUC0.5523 (95% CI 0.4522 – 0.524, p = 0.049)) demonstrated lower predictive values, while SIMD demonstrating better prediction of AF recurrence requiring readmission (AUC 0.6145 (95% CI 0.5144 - 0.7146, p=0.001)). SIMD also demonstrated to better predicts recurrence of subjective AF recurrence (AUC 0.6096 , 0.5095 - 0.7097, p <0.001). Addition of SIMD into CHADS2VASc, R2CHADS2 or APPLE Score through various modeling did not improve predictive value of AF recurrence or readmission.ConclusionScottish Index of Multiple Deprivation is superior to the CHA2DS2-VASc, R2CHADS2 and APPLE scores for prediction of readmission and recurrence of symptomatic AF after AF cryoablation.Conflict of InterestNo

The role of catheter ablation in patients with symptomatic atrial fibrillation and end-stage heart failure is unknown. We conducted a single-center, open-label trial in Germany that involved patients with symptomatic atrial fibrillation and end-stage heart failure who were referred for heart transplantation evaluation. Patients were assigned to receive catheter ablation and guideline-directed medical therapy or medical therapy alone. The primary end point was a composite of death from any cause, implantation of a left ventricular assist device, or urgent heart transplantation. A total of 97 patients were assigned to the ablation group and 97 to the medical-therapy group. The trial was stopped for efficacy by the data and safety monitoring board 1 year after randomization was completed. Catheter ablation was performed in 81 of 97 patients (84%) in the ablation group and in 16 of 97 patients (16%) in the medical-therapy group. After a median follow-up of 18.0 months (interquartile range, 14.6 to 22.6), a primary end-point event had occurred in 8 patients (8%) in the ablation group and in 29 patients (30%) in the medical-therapy group (hazard ratio, 0.24; 95% confidence interval [CI], 0.11 to 0.52; P<0.001). Death from any cause occurred in 6 patients (6%) in the ablation group and in 19 patients (20%) in the medical-therapy group (hazard ratio, 0.29; 95% CI, 0.12 to 0.72). Procedure-related complications occurred in 3 patients in the ablation group and in 1 patient in the medical-therapy group. Among patients with atrial fibrillation and end-stage heart failure, the combination of catheter ablation and guideline-directed medical therapy was associated with a lower likelihood of a composite of death from any cause, implantation of a left ventricular assist device, or urgent heart transplantation than medical therapy alone. (Funded by Else Kröner-Fresenius-Stiftung; CASTLE-HTx ClinicalTrials.gov number, NCT04649801.).

Background. Radiofrequency ablation (RFA) of CTI dependent atrial flutter (CTI-AFL) is conventionally performed under fluoroscopic guidance, or alternatively with 3D mapping and contact force (CF) catheters. Ultra-high density mapping (UHDm) and local impedance (LI) guided ablation have not yet been evaluated for this indication.Methods. An observational study comparing conventional, CF and LI-guided ablation of CTI-AFL to understand whether LI offers superior ablation metrics and UHDm allows accurate identification of breakthrough after initial RFA.Retrospective analysis of consecutive CTI-AFL cases was performed. Irrigated RFA was used in all groups. Contact was determined in the CF group with target >9 g and in the LI group with patient-specific LI. Target LI drop of -20 ohms was used to determine effective lesion formation. Standard generator impedance was used for the conventional group. Power was limited to 40-50W in all groups. In the LI group, if the CTI was not blocked after initial ablation, UHDm was used to identify breakthrough. Mean RFA time, time to CTI block, number of lesions required to achieve block, acute procedural success and complications were analysed with ANOVA. Breakthrough points were manually assessed.Results. Data is presented for 27 patients; 7 conventional, 10 CF and 10 LI. Mean RFA time was 6, 5.8, 3.2min respectively (p=0.0227). Significant differences also seen with LI vs Fluo (p=0.0194), LI vs CF (p=0.0164). Time from first application of RF to block was 22.8, 20.4, 14.2 min (p=ns). No significant difference was seen in the number of lesions required to achieve block. Acute procedural success was 100% in all groups, and there were no acute complications.Breakthrough was identified in 50% of CF and LI cases (5 patients in each group). With LI, there was one case of epicardial-endocardial breakthrough (EEB) 11mm from the CTI (figures A, B), three posterior, and one anterior aspect of the CTI, identified with UHDm. Subsequent LI-guided RFA resulted in block, on average six minutes quicker vs CF.Abstract 66 Figure 1A) Left lateral caudal view of CTI line following failure to demonstrate bi-directional isthmus block. UHD mapping shows EEB away from the line (point ‘y’); B) Right anterior oblique caudal view of ablation line following further RFA of EEB site (pink lesions at point ‘y’) resulting in bi-directional CTI blockDiscussionThis data illustrates that UHDm and LI-guided RFA significantly reduces the amount of ablation required (by 47% and 45% versus conventional and CF respectively; p=sig) by shortening lesion duration guided by LI change. A reduction from first RFA to block is also seen (47% and 30% respectively; p=ns). Many patients require further ablation following the initial RFA line, resulting in longer procedures. UHD mapping quickly and accurately identifies breakthrough for further focused RFA, including EEB away from the CTI which may otherwise be difficult to identify and treat using the conventional or standard 3D mapping, and result in prolonged procedure time and/or increased radiation exposure. LI also resulted in more predictable procedure times. We could not directly compare overall procedure times as many in the CF group had CTI combined with left atrial ablation.Conclusion. LI-guided ablation is safe and effective, and has shown favourable ablation metrics when compared with conventional and CF-guided ablation for CTI dependent AFL. Ultra-high density mapping more rapidly and effectively identifies sites of breakthrough after initial RFA application. A larger study is planned to provide more insight.Conflict of InterestNone

Over 700 patients with drug-refractory paroxysmal atrial fibrillation were randomly assigned to cryoballoon or radiofrequency ablation. Cryoballoon ablation was noninferior to radiofrequency for the composite of recurrent atrial arrhythmia, use of antiarrhythmic drugs, or repeat ablation. According to a 2012 expert consensus statement, catheter ablation of drug-refractory paroxysmal atrial fibrillation is a class I level A indication, 1 and pulmonary-vein isolation is the standard approach. 1 – 3 The two most frequently used ablation technologies for pulmonary-vein isolation differ in the energy source and mode of application. The most common method is the use of radiofrequency current applied in a point-by-point mode, which leads to cellular necrosis by tissue heating; the other method is the use of cryogenic energy applied with a balloon in a single-step mode, which leads to necrosis by freezing (Figure 1). Radiofrequency ablation for atrial . . .

In a randomized trial involving patients with paroxysmal atrial fibrillation, pulsed field ablation was noninferior to thermal ablation with respect to freedom from a composite of procedural and arrhythmia events at 1 year.

Image-guided percutaneous ablation is considered best in the treatment of early-stage hepatocellular carcinoma (HCC). Ablation is potentially curative, minimally invasive, and easily repeatable for recurrence. Ethanol injection used to be the standard in ablation. However, radiofrequency ablation has recently been the most prevailing ablation method for HCC. Many investigators have reported that radiofrequency ablation is superior to ethanol injection, from the viewpoints of treatment response, local tumor curativity, and overall survival. New-generation microwave ablation can create a larger ablation volume in a shorter time period. Further comparison studies are, however, mandatory between radiofrequency ablation and microwave ablation, especially in terms of complications and long-term survival. Irreversible electroporation, which is a non-thermal ablation method that delivers short electric pulses to induce cell death due to apoptosis, requires further studies, especially in terms of long-term outcomes. It is considerably difficult to compare outcomes in ablation with those in surgical resection. However, radiofrequency ablation seems to be a satisfactory alternative to resection for HCC 3 cm or smaller in Child-Pugh class A or B cirrhosis. Furthermore, radiofrequency ablation may be a first-line treatment in HCC 2 cm or smaller in Child-Pugh class A or B cirrhosis. Various innovations would further improve outcomes in ablation. Training programs may be effective in providing an excellent opportunity to understand basic concepts and learn cardinal skills for successful ablation. Sophisticated ablation would be more than an adequate alternative of surgery for small- and possibly middle-sized HCC.

In patients with persistent atrial fibrillation, rates of recurrent atrial fibrillation at 18 months were not significantly different when linear ablation or ablation of complex fractionated electrograms was performed along with pulmonary-vein isolation. Percutaneous catheter ablation is an effective treatment for paroxysmal atrial fibrillation, 1 – 3 particularly in cases that are refractory to antiarrhythmic medications. 4 – 6 Most triggers for paroxysmal atrial fibrillation come from the pulmonary veins, so ablation involves creating circumferential lesions around the veins to electrically isolate them from the rest of the left atrium. 7 Catheter ablation for persistent atrial fibrillation is more challenging and is associated with less favorable outcomes. 8 , 9 To improve outcomes, ablation targeting the substrate that maintains fibrillation (i.e., substrate modification) is often added to pulmonary-vein isolation. 10 , 11 The two most common techniques for substrate modification are the . . .