Catheter Ablation Of Ventricular Arrhythmias Research Articles

Preventive catheter ablation for ventricular arrhythmias in patients with end-stage heart failure referred for heart transplantation evaluation: Rationale for and design of the CASTLE-VT trial.

Timely referrals for transplantation and left ventricular assist device (LVAD) play a key role in favourable outcomes in patients with advanced heart failure (HF). Cardiovascular mortality, driven by sudden cardiac death, is the main reason for dying while waiting for heart transplantation (HTx). The purpose of the Preventive Catheter Ablation for ventricular arrhythmiaS in patients with end-sTage heart faiLure rEferred for heart transplantation eValuaTion (CASTLE-VT) trial is to test the hypothesis that prophylactic catheter ablation of arrhythmogenic ventricular scar tissue will reduce mortality, need for LVAD implantation, and urgent HTx in patients with end-stage HF related to ischaemic cardiomyopathy (ICM). CASTLE-VT is a randomized evaluation of prophylactic ablative treatment of arrhythmogenic ventricular scar in patients referred for HTx evaluation and diagnosed with ICM. Ablation will be performed with the use of a substrate-based approach in which the myocardial scar is mapped and ablated while the heart remains predominantly in sinus rhythm. The primary endpoint is the composite of all-cause mortality, worsening of HF requiring prioritized transplantation or LVAD implantation. The main secondary study endpoints are all-cause mortality, cardiovascular mortality, incidence of implantable cardioverter-defibrillator (ICD) therapy, hospitalizations, quality of life, time to first ICD therapy, number of device-detected ventricular tachycardia/ventricular fibrillation episodes, left ventricular function, and exercise tolerance. CASTLE-VT will randomize 160 patients with a follow-up period of 2 years. CASTLE-VT will determine whether prophylactic catheter ablation of arrhythmogenic ventricular scar tissue reduces mortality in patients with end-stage HF who are referred for HTx evaluation.

Nationwide trends in utilization and safety of ventricular arrythmia ablation in patients with hypertrophic cardiomyopathy

Abstract Background Catheter ablation for ventricular arrhythmias, including ventricular tachycardia (VT) and premature ventricular complexes (PVC) is increasingly utilized across the nation, while data on its safety in Hypertrophic Cardiomyopathy (HCM) patients is sparse. Purpose To analyze the nationwide trends in utilization and complications of inpatient ventricular arrhythmia ablations in patients with HCM. Methods This study is a retrospective analysis of hospitalizations, in HCM patients 18 years of age and older, who underwent an inpatient VA ablation in the U.S., between 2016 and 2020. We drew data from the National Inpatient Sample (NIS) database. Patients without HCM undergoing the CA for VA were used as controls. Baseline sociodemographic and clinical data, procedural complications, mortality and length of stay were analyzed. Multivariable analysis was performed to identify independent predictors of procedural complications. Results Among a weighted total of 2880 patients hospitalized between 2016 and 2020, who underwent VA ablations, the median age was 67 years (IQR 56-74), 60% were male, and 73% were white. The HCM group had similar age distribution but more women (64.5% vs 33.6%, p<0.001) and more African Americans (13.2% vs. 7.3%, p=0.03). The non-HCM cohort had significantly higher rates of prior myocardial infarction (22% vs 12.4%, p=0.026), ischemic cardiomyopathy (30.1% vs 0.8%, p<0.001), heart failure (70.5% vs 39.7%, p<0.001), and peripheral vascular disease (PVD, 42.9% vs 18.2%, p<0.001). This was reflected in higher Deyo Comorbidity Index in the non-HCM cohort (score of ≥ 2 in 66.6% vs 43%, p<0.001). Overall, the real-world peri-procedural complication rate in the entire cohort was 15.3%, including 6.4% hemorrhagic, 4.5% pericardial, and 2.3% vascular complications. There was a trend for lower complication rate in the HCM group (9.9% vs. 16.7%, p = 0.08). The in-hospital mortality didn’t defer (1.7% vs. 4.2%, p=0.28) and the length of stay was shorter in the HCM group (3.5 vs. 6.4 days, p < 0.001). Multivariable logistic regression analysis showed obesity (OR 2.06; 95%CI: 1.59 - 2.67; p<0.001) and PVD (OR 2.19; 95%CI: 1.34-3.53; p=0.001) to be independent predictors of complications while HCM was not (OR 0.76, 95% CI 0.51-1.14, p = 0.195). Conclusion Real-world data from a nationwide inpatient database shows comparable safety for VA ablation in HCM patients with similar mortality and lower length of stay, compared to non-HCM patients.

Preliminary results of the non-invasive cardiac radioablation for ventricular tachycardia study; an in silico dosimetric comparison of photon vs proton radiotherapy for ventricular arrhythmias

Abstract Background Stereotactic arrhythmia radio-ablation (STAR) has been proposed as an alternative treatment for refractory ventricular arrhythmias (VA) in patients who are unsuitable or refractory to standard catheter ablation (CA). It consists in the application of external beam radiotherapy in a single dose of 25 Gy to the target areas. Most of the STAR treatments performed so far used photon radiotherapy. As compared to photons, particle therapy with protons, based on its finite penetration depth in tissue, might have the potential to reduce the dose to surrounding healthy tissues thus lowering the risk of side effects. Purpose The purpose of this in silico simulation study was to evaluate the feasibility of STAR with protons in patients with VA and to compare the doses of the organs at risk (OARs) in photon and proton treatment plans. Methods 14 patients (11 males) candidates to standard CA for VA were enrolled. ECG gated CT scans in expiratory breath-hold, and standard electroanatomical mapping were performed in each patients to reconstruct a 3D bipolar voltage map and identify the ablation target. Based on the information obtained by the contouring of the ablation target three treatment plans were simulated: one with photons, and two with protons - with and without cardiac gating- to assess the doses at the OARs. Results The median age was 68.5 (63.25-71.5), all patients had a history of recurrent VA and the indication for treatment with CA. 7 patients had an ischemic cardiomyopathy, 4 an idiopathic cardiomyopathy and 3 ventricular ectopic beats without structural heart disease. The mean left ventricular ejection fraction was 40±11% and 8 out of 14 patients were ICD carriers. Both photons and protons treatment plans reached the goals for target coverage (25 Gy on 98% of the target volume). A statistically significant reduction in the mean maximum dose (Dmax) to some OARs was observed in proton compared to photon plans (see table 1). Specifically, the Dmax delivered to the mitral valve, vena cava, descending aorta, esophagus and to the lungs have been largely reduced with the proton plans. However, in some specific cases, a higher maximum dose was observed for protons in structures close or overlapping with the target, mainly due to the need of an additional margin in the treatment plan to account for proton range uncertainty. The use of cardiac gating did not show a significant dose reduction to OARs compared to the non-gated proton plan. Conclusion The preliminary results of our in silico simulation study suggest that STAR therapy with the use of protons might be associated with a significant dose reduction to the surrounding organs. Nevertheless, the choice of the best treatment should be evaluated on a case by-case strategy since some specific cases may be better suitable for photon treatment.Table 1

Vascular access complications after catheter ablation of ventricular arrhythmias: Impact of vascular closure devices

BackgroundVascular access site complications are the most frequent complications of percutaneous catheter ablation (CA) of ventricular arrhythmias (VAs). Whether arterial/venous vascular closure devices (VCDs) prevent vascular complications is unknown. ObjectiveWe investigated the benefit of VCDs in patients undergoing CA of VAs. MethodsConsecutive CA of VAs were included (2018–2022). Vascular accesses were obtained with ultrasound guidance. At the discretion of the operator, arterial and/or venous VCDs were used. Cases were divided into 3 groups: no use of VCDs for any arterial/venous accesses (manual compression [MC]), use of VCDs for some but not all accesses (Partial-VCDs), and use of VCDs for all accesses (Complete-VCDs). Vascular complications were classified as minor if they did not require intervention or major if they required intervention. ResultsA total of 1016 procedures were performed in 872 patients (mean age 62 ± 13 years; mean body mass index 30 ± 6 kg/m2; 27% female) during the study period. Femoral arterial access was obtained in 887 procedures (875 single access: 7.4 ± 1.5 F size; 12 two accesses: 7.3 ± 3 and 6.9 ± 1.8 F). Femoral venous access was obtained in 1014 procedures (unilateral in 17%; bilateral in 83%; mean number of access sites per patient 2.6 ± 0.7; mean size 8.4 ± 1.3 F). Hemostasis was achieved with MC in 192 procedures (19%), with Partial-VCD in 275 (27%), and with Complete-VCD in 549 (54%). A vascular complication occurred in 52 procedures (5.1%), including a minor hematoma in 3.9% and/or a major complication in 1.7%. The rate of vascular complications was 6.8% (5.2% minor and 1.6% major) in the MC group, 7.6% (5.1% minor and 3.3% major) in the Partial-VCD group, and 3.3% (2.9% minor and 0.9% major) in the Complete-VCD group (P = .014 for comparison). In multivariable analysis, Complete-VCD remained independently associated with a lower risk of vascular complications (odds ratio 0.69; 95% confidence interval 0.48–0.96; P = .036). ConclusionIn patients undergoing CA of VAs, Complete-VCD is associated with lower rates of vascular-related complications compared with MC or Partial-VCD.

Long-term outcomes of catheter ablation for ventricular arrhythmias: comparing techniques with and without intracardiac echocardiography - what matters?

BackgroundThe increasing use of intracardiac echocardiography (ICE) in the ablation of premature ventricular complexes (PVCs) has raised questions about its true efficacy and safety.MethodsThis retrospective study collected the periprocedural complications and PVC burden post ablation. The risk factors of PVC recurrence was further explored.ResultsThe study included patients treated without ICE (control group, n = 451) and with ICE (ICE group, n = 155) from May 2019 to July 2022. The ICE group demonstrated significantly lower fluoroscopy times and X-ray doses. There were no major complications in the ICE group, and the difference in the occurrence of periprocedural complications between the groups was not statistically significant (p = 0.072). The long-term success rates were similar for the control and ICE groups (89.6% and 87.1%, respectively). The origin of PVCs was identified as the independent factor for ablation success.ConclusionsThe use of ICE did not confer an advantage with regard to long-term success in PVCs ablation. To thoroughly evaluate the safety and effectiveness of ICE in PVCs ablation, a prospective, multicenter, randomized study is warranted.

Exploring suitability to electrical storm ablation in patients in waiting list for heart transplantation: A single center experience.

Electrical storm (ES) is among the most fearsome events in patients in waiting list for heart transplantation (HT) and catheter ablation (CA) demonstrated to be effective in reduce the arrhythmic burden. However, selection criteria for CA suitability in this specific population have never been addressed before. We retrospectively enrolled 36 patients (mean age 51±8 years; 83% men) waiting HT referred to our department for ES resistant to antiarrhythmic drugs and percutaneous stellate ganglion blockade. Twenty patients were judged suitable for VT ablation according to specific criteria including absence of increased arrhythmic burden secondary to volume overload and hemodynamic decompensation; expected CA outcome favorable due to etiology of the cardiomyopathy, no need for coronary revascularization and technical feasibility of the procedure. The pre-emptive use of mechanical circulatory supports (MCS) were discussed integrating the PAINESD score with additional clinical and hemodynamic parameters. Acute procedural success was accounted in 85% of cases with only two major complications. The CA group reported lower length of in-hospital stay after CA suitability evaluation (56±17vs. 131±64 days, p=.004). Furthermore, at a mean follow-up of 703±145 days, this group showed reduction of ventricular arrhythmia (VA) recurrence leading to implantable cardioverter defibrillator shock (4vs. 8, p=.051) and underwent HT with a lower level of urgency (0vs. 6 patients needed for UNOS1 status upgrade). Respectively, one patient of the CA group and two patients of the conservative group died (p=.839). At the end of follow-up, eight patients underwent heart transplantation (p=.964) while four patients underwent Left Ventricular Assist device (LVAD) implantation (p=.440). This pilot study should be a proof for further studies exploring CA of VAs as a possible bridge therapy to HT.

Percutaneous mechanical support in catheter ablation of ventricular arrhythmias: hype or hope?

Catheter ablation (CA) has become an established treatment strategy for managing recurrent ventricular tachycardias (VTs) in patients with structural heart disease. In recent years, percutaneous mechanical circulatory support (PMCS) devices have been increasingly used intra-operatively to improve the ablation outcome. One indication would be rescue therapy for patients who develop haemodynamic deterioration during the ablation. However, more efforts are focused on identifying subjects who are at high risk of such deterioration and could benefit from the pre-emptive use of the PMCS. The third reason to use PMCS could be the inability to identify diffuse substrate, especially in non-ischaemic cardiomyopathy. This paper reviews available experiences using various types of PMCS in different clinical scenarios. Although PMCS allows mapping during VT, it does not significantly influence acute outcomes and not convincingly long-term outcomes. On the contrary, the complication rate appears to be higher in PMCS cohorts. Our data suggest that even in patients with severe left ventricular dysfunction, the substrate modification can be performed without the need for general anaesthesia and risk of haemodynamic decompensation. In end-stage heart failure associated with the electrical storm, implantation of a left ventricular assist device (or PMCS with a transition to the left ventricular assist device) might be the preferred strategy before CA. In high-risk patients who are not potential candidates for these treatment options, radiotherapy could be considered as a bail-out treatment of recurrent VTs. These approaches should be studied in prospective trials.

Efficacy and safety of focal pulsed-field ablation for ventricular arrhythmias: two-centre experience.

A pulsed electric field (PF) energy source is a novel potential option for catheter ablation of ventricular arrhythmias (VAs) as it can create deeper lesions, particularly in scarred tissue. However, very limited data exist on its efficacy and safety. This prospective observational study reports the initial experience with VA ablation using focal PF. The study population consisted of 44 patients (16 women, aged 61 ± 14years) with either frequent ventricular premature complexes (VPCs, 48%) or scar-related ventricular tachycardia (VT, 52%). Ablation was performed using an irrigated 4 mm tip catheter and a commercially available PF generator. On average, 16 ± 15 PF applications (25 A) were delivered per patient. Acute success was achieved in 84% of patients as assessed by elimination of VPC or reaching non-inducibility of VT. In three cases (7%), a transient conduction system block was observed during PF applications remotely from the septum. Root analysis revealed that this event was caused by current leakage from the proximal shaft electrodes in contact with the basal interventricular septum. Acute elimination of VPC was achieved in 81% patients and non-inducibility of VT in 83% patients. At the 3-month follow-up, persistent suppression of the VPC was confirmed on Holter monitoring in 81% patients. In the VT group, the mean follow-up was 116 ± 75 days and a total of 52% patients remained free of any VA. Pulsed electric field catheter ablation of a broad spectrum of VA is feasible with acute high efficacy; however, the short-term follow-up is less satisfactory for patients with scar-related VT.

Electrophysiological characteristics and catheter ablation of ventricular arrhythmias arising from the superior septal left ventricle

Background and aimsElectrophysiological characteristics and radiofrequency catheter ablation (RFCA) of premature ventricular contractions (PVCs) originating from the superior septal left ventricle (SSLV) have not yet been fully characterized.Methods and resultsThis study included 247 patients who underwent RFCA for PVCs arising from the ventricular outflow tract between February 2020 and August 2022. The successful ablation site was on the SSLV in 37 of the 247 patients. In 12 (32.4%) of those 37 patients, a low amplitude and high frequency spiky potential (SP) was recognized. Five patients showed a narrow QRS duration (86.8 ± 4.6 ms), with a discrete SP observed in PVCs and sinus rhythm, which showed an isoelectric line with the ventricular electrogram at the earliest activation site. Seven patients showed a wide QRS duration (131.6 ± 4.5 ms), with SP observed in PVCs without an isoelectric line with the ventricular electrogram. RFCA was successful at the site of the earliest SP in all 12 patients. The time from SP onset at the successful ablation site to the QRS onset (local activation time) was 30 ± 12 ms, which differed significantly from that for the remaining 25 patients withoutSP(22.1 ± 7.1 ms, P < 0.05).ConclusionsSPs were recorded in 12 (32.4%) of the 37 patients with PVCs originating from the SSLV. The morphology of the PVCs may show a narrow or wide QRS duration and the target site for successful ablation should be identified by the earliest SP.

Real life experience with point by point pulsed field ablation for recurrent ventricular arrhythmias

Abstract Introduction The safety and effectiveness of electroporation/point by point pulsed field ablation (PP PFA) as emerging technoloy for catheter ablation (CA) of ventricular arrhythmias (VAs) has been described till now only in case reports. Purpose The aim of this observational retrospective study is to present real life data concerning the overall performance of PP PFA for CA of recurrent VA. Methods A total number of 13 consecutive patients (11 VTs and 2 PVCs), in whom recurrent VTs after RF ablation documented, were included. In all patients the substrate location was documented beforehand based on cardiac MRI or CT with myocardial thinning. For substrate mapping a high resolution multipoint mapping catheter was used. A complete success was defined as non inducibility of any arrhythmia at the end of procedure respectively lack of VA recurrence at follow – up. Results Excepting 2 patients, all other had a non ischemic cardiomyopathy as underlying heart disease (mean age 63 ± 8 y/o, mean LVEF 42 % ± 9 %). In every patient at least one conventional RF CA has been performed previously (mean 2 ± 1) and 38 % of patients had a previous epicardial RF VT ablation. The PP PFA VT ablation was performed endocardialy in 11 patients (84 %), respectively epicardialy in 2 patients. The ablation sites had a septal location in 53 % of patients and other localisation in 47 % of patients. The applied energy was 25 A. The overall acute complete success was achieved in 77 % patients. At medium 6 ± 3 months follow up a complete success was present in 46 % cases. Most frequently a VT recurrence after PP PFA ablation was encountered in patients with combined septal and nonseptal substrate distrubution. After PP PFA, the RF CA strategy due to recurrent VAs was endocardial in 2 patients, respectively epicardial 2 in cases and bipolar in 1 case. No PP PFA redos were undergone. Three major complications have been documented (1 tamponade, 1 AV block III° and 1 complete LBBB). Conclusion As bailout strategy in patients with failed conventional CA, PP PFA represents a safe strategy. Specific complications like temporary atrioventricular or intraventricular conduction disturbancies are extremely rare, reversible but not life threathening. The midterm success is satisfactory but still limited in patients with intramural substrate.

Novel systematic processing of cardiac magnetic resonance imaging identifies target regions associated with infarct-related ventricular tachycardia

Abstract Introduction In the clinic, complete characterization of reentrant ventricular tachycardia (VT) circuits using classical electrophysiological criteria and state-of-the-art high density mapping during VT is complex, and often cannot be completed because of hemodynamic instability. This common limitation has motivated the implementation of mapping strategies during sinus rhythm or ventricular pacing aiming to identify scar regions associated with VT isthmuses or potential arrhythmogenicity. Complementary imaging-based strategies including advanced analyses of scar tissue characteristics have been also proposed for procedure planning and identification of potential arrhythmogenic regions. However, the most recent expert consensus report on catheter ablation of ventricular arrhythmia highlights the lack of agreement on the preferable signal intensity (SI) cut-off values for assessment of tissue heterogeneity and scar areas on late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) images. The latter makes LGE-CMR imaging processing highly operator-dependent and potentially sensitive to selection bias. Purpose We aimed at developing and validating a systematic processing approach on LGE-CMR images to identify potential VT corridors that may include protected isthmuses associated with VT maintenance. Methods Translational study including 18 pigs with established myocardial infarction and inducible VT undergoing in vivo characterization of the anatomical and functional myocardial substrate associated with VT maintenance. Clinical validation was conducted in a multicenter series of 33 patients with ischemic cardiomyopathy undergoing VT ablation. Three-dimensional CMR-LGE images were processed using systematic scanning of 15 signal intensity cut-off ranges to obtain surface visualization of all potential VT corridors. Analysis and comparisons of imaging and electrophysiological data were performed in individuals with full electrophysiological characterization of the isthmus sites of at least one VT morphology. Results In both the experimental pig model and patients undergoing VT ablation, all the electrophysiologically-defined isthmus sites (n=11 and n=19, respectively) showed overlapping regions with CMR-based potential VT corridors. Such imaging-based VT corridors were less specific than electrophysiologically-guided ablation lesions at functionally relevant isthmus sites (Figure). However, in patients, decreasing from 15 to 7 the number of signal intensity cut-off ranges for systematic imaging processing significantly reduced the area of imaging-based potential VT corridors, without diminishing the capability to detect functionally relevant VT isthmus sites. Conclusions Systematic processing of 3D LGE-CMR images provides unbiased identification of imaging based potential VT corridors that contain functionally relevant protected isthmus sites.

Effects of hemodynamic support on arrhythmia-free survival following catheter ablation of ventricular arrhythmias

Abstract Background Radiofrequency-guided catheter ablation is an established therapy for ventricular tachycardia (VA). Hemodynamic support (HS) is often required for patients suffering from incessant VA to guide ablation. Data on the outcome of patients receiving HS during VA ablation procedures are lacking. Purpose The aim of this observational study was to analyze the acute procedural success as well as long-term 36-month-VA-recurrence rates and mortality in patients requiring HS during VA ablation procedures. Methods Data from consecutive patients receiving HS during VA ablation procedures between 2015-2023 were analyzed. HS was defined as the use of an Impella, an extracorporeal membrane oxygenation (ECMO) or a left ventricular assist device (LVAD). HS-group patients were compared to patients that underwent VA ablation procedures without HS. All patients were continuously followed up in our outpatient clinic. Data on procedural parameters, acute success and complications as well as long-term VA-free survival and mortality were analyzed. Results A total of 95 consecutive patients (mean age 60.9 ± 11.0 years, 15% female) were included. 62 patients (65%, mean age 60.4±9.4 years, 16% female) receiving HS (ECMO or Impella: n=26, 42%; ECMO+Impella: n=7, 11%; LVAD: n=29, 47%) were compared to those without (mean age 61.7±13.5 years, 12 % female). In the HS-cohort a significantly lower left ventricular ejection fraction (LVEF) (p&amp;lt;0.001), a higher New York Heart Association (NYHA) functional class (p=0.013) and a more frequent antiarrhythmic drug use (p=0.045) was documented. Fluoroscopy times were significantly longer in the HS-group (HS: 10:22 ± 07:04 vs. no HS: 05:52 ± 02:50 minutes, p&amp;lt;0.001). Acute procedural success (HS: n=59, 95% vs. no HS: n=33, 100%, p=0.549) and major procedure complications (HS: n=4. 6% vs. no HS: n=4. 6%, p=1.000) were comparable between the two groups. Nevertheless, patients receiving HS had a significantly higher in-hospital mortality (HS: n=20, 32 % vs. no HS: n=2, 6%, p=0.004). The estimated 36-month-VA-free survival was comparable between the groups (Log-rank p=0.114). But Kaplan-Meier-plot analyses revealed a significantly higher estimated mortality in patients receiving HS (Log-rank p=0.002) (Figure 1). Between the subgroups (ECMO or Impella vs. LVAD) no statistically relevant differences were observed (Log-rank p=0.466). Multivariate analyses revealed HS as an independent predictor for mortality (Hazard ratio (HR) 3.259, Confidence Interval (CI) 1.060-10.015, p=0.039), but not for VA-recurrence. Conclusion In the specific cohort of patients receiving HS, VA ablation procedures seem to be safe and effective with comparable acute and long-term success- and complication-rates. The need for HS seems to be associated with an increased risk for mortality. Further studies are required to validate our initial observations.Kaplan-Meier-plot on 36-month survival

First experience of focal pulsed field ablation for premature ventricular contractions

Abstract Introduction Pulsed field ablation (PFA) has emerged as a novel strategy to achieve ablation of cardiac tissue. Clinical evidence suggests a remarkable lesion durability and safety profile for AF ablation. Nonetheless, a growing interest exists in broadening its field of application for catheter ablation of ventricular arrhythmias (VA). The CENTAURI system arises as a promising PFA system for targeting VA as it allows pulsed electric field (PEF) delivery via standard, commercially available focal ablation catheters and concomitant coupling with their mapping systems. Purpose To assess, for the first time, the feasibility of focal PFA via the CENTAURI system for premature ventricular complex (PVC) ablation. Methods We conducted a prospective analysis of patients with either high burden (&amp;gt;10%) or symptomatic idiopathic PVC undergoing focal PFA using CENTAURI system at our institution. Procedures were performed between December 2022 and August 2023. Acute and long-term success were defined as no PVC recurrence during a 24h in-hospital monitoring period, and ≥80% burden reduction with absence of symptoms after at least 30 days post-ablation, respectively. PVC monitoring was performed by implantable loop recorder (ILR) or surface ECG Holter monitoring. Results Fourteen patients (age range: 16-87 years; 10 females) were included. Procedures were performed via the CENTAURI system in combination with CARTO 3 system and EnSite X EP system in 4 (28.6%) and 10 cases (71.4%) respectively. Targeted ablation sites were the right ventricular outflow tract (6 cases), right moderator band (2 cases), left postero-medial papillary muscle -PM- (2 cases), and right posterior PM, tricuspid annulus, left posterior fascicle and aortomitral continuity (AMC) in one case. On average, 6.5 applications were delivered to the site of origin with a mean contact force of 11g. Procedural duration and fluoroscopy time were 102 and 8.9 minutes. Two minor complications were observed: one transitory ST depression (solved after i.v. nitrate administration) after repeated applications to AMC, and a femoral pseudoaneurysm. The remaining 12 procedures were uneventful. Although most of the procedures were performed under general anesthesia due to concerns about potential significant muscular contraction, 3 cases (21.4%) were successfully managed with light sedation, without significant muscular contraction nor map shift. Incomplete abolishment of PVC during first 24 h was observed in 2 patients (14.3%). After a median follow-up of 113 days (IQR: 83-188), recurrences were detected in one patient (7.14%). Conclusion Herein we report the feasibility and efficacy of PVC ablation using a focal PEF delivery system (CENTAURI). Furthermore, we describe the possibility of performing PVC ablation with this technology under light sedation, which might be important for minimizing anesthesia impact on PVC burden.Table of characteristicsPVC morphologies

Catheter ablation as an adjunctive therapy to ICD implantation in Brugada Syndrome.

Brugada Syndrome (BrS) is a life-threatening cardiac arrhythmia disorder associated with an increased risk of ventricular arrhythmias (VAs) and sudden cardiac death. Current management primarily relies on implantable cardioverter-defibrillators (ICDs), but patients may experience ICD shocks. Catheter ablation (CA) has emerged as a potential intervention to target the arrhythmogenic substrate. This systematic review aims to evaluate the safety and efficacy of CA in BrS patients. Studies with BrS patients undergoing CA for VAs were included. Fourteen studies that involved a total population of 709 BrS patients, with CA performed in 528 of them, were included. CA resulted in the non-inducibility of VAs in 91% (95% CI: 83-99, I2=76%) and resolution of type 1 ECG Brugada pattern in 88% (95% CI: 81-96.2, I2=91%) of the patients. After a mean follow-up of 30.7 months, 87% (95% CI: 80-94, I2=82%) of patients remained free from VAs. The incidence of VAs during follow-up was significantly lower in the ablation cohort in comparison to the group receiving only ICD therapy (OR=0.03, 95% CI: 0.01-0.12, I2=0%). CA shows potential as a therapeutic approach to reduce VAs and improve outcomes in BrS patients. While further research with a long follow-up period is required to confirm these findings, it represents a valuable tool as an add-on intervention to ICD implantation in BrS patients with a high burden of VAs.

Anatomical approach to suppression of para-Hisian ventricular arrhythmias with changes in QRS morphology after ablation at the earliest activation site

BackgroundThe anatomical approach for the management of para-Hisian ventricular arrhythmias (VAs) with QRS morphological changes after catheter ablation (CA) has not been well investigated. ObjectiveWe aimed to evaluate the electrocardiographic and electrophysiological findings and ablation outcomes of para-Hisian VAs with QRS morphological changes after CA. MethodsOf the 30 patients who underwent CA for para-Hisian VAs at 4 institutions, 10 (33%) had QRS morphological changes after ablation. All 10 patients underwent an anatomical approach, targeting the site anatomically opposite to the site where the QRS morphology had been changed by ablation. We investigated the safety and efficacy of the anatomical approach. ResultsOf the 10 patients evaluated, the approach was switched from the right ventricular septum to the left ventricular septum/aortic root in 7 (70%) (RL group) whereas 3 (30%) underwent left-to-right switches (LR group). After CA, the precordial transition zone tended to be earlier in the RL group and later in the LR group. In the RL group, successful VA suppression was achieved, despite suboptimal pace map concordance from the left side or a relatively delayed earliest activation time. Of the 10 patients who underwent an anatomical approach, 8 (80%) had procedural success, and ablation was discontinued in 1 (10%) because of the risk of atrioventricular block. ConclusionThe anatomical approach showed promising results regarding safety and efficacy. Therefore, it should be considered when QRS morphological changes are observed during or after CA of para-Hisian VAs.

Management of ventricular tachycardias: insights on centre settings, procedural workflow, endpoints, and implementation of guidelines-results from an EHRA survey.

Ventricular tachycardia (VT), and its occurrence, is still one of the main reasons for sudden cardiac death and, therefore, for increased mortality and morbidity foremost in patients with structural heart [Kahle A-K, Jungen C, Alken F-A, Scherschel K, Willems S, Pürerfellner H et al. Management of ventricular tachycardia in patients with ischaemic cardiomyopathy: contemporary armamentarium. Europace 2022;24:538-51]. Catheter ablation has become a safe and effective treatment option in patients with recurrent VT [Cronin EM, Bogun FM, Maury P, Peichl P, Chen M, Namboodiri N et al. 2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias. Heart Rhythm 2020;17:e2-154]. Previous and current guidelines provide guidance on indication for VT ablation and risk assessment and evaluation of underlying disease. However, no uniform recommendation is provided regarding procedural strategies, timing of ablation, and centre setting. Therefore, these specifics seem to differ largely, and recent data are sparse. This physician-based European Heart Rhythm Association survey aims to deliver insights on not only infrastructural settings but also procedural specifics, applied technologies, ablation strategies, and procedural endpoints. Therefore, these findings might deliver a real-world scenario of VT management and potentially are of guidance for other centres.

Predictors of unsuccessful radiofrequency catheter ablation of idiopathic ventricular arrhythmias in children

Ventricular arrhythmias (VAs) in children are generally idiopathic and have a benign course. Catheter ablation (CA) is increasingly becoming a first-line treatment option in children with idiopathic VAs. Acute ablation success reaches 100% procedures and long-term – 87%. Predictors of outcomes of CA in pediatric patients with idiopathic VAs have not been fully investigated.Aim: To identify predictors of long-term unsuccessful outcomes of CA in pediatric idiopathic VAs.Material and Methods. This retrospective study included 164 children aged 7 to 17 years with idiopathic VAs, who underwent CA from 2011 until 2023 in Almazov National Medical Research Centre. Efficiency was assessed in acute period and 6 months after CA.Results. In this study the acute success was 92% and long-term success was 88,4%. In multivariable models, multifocal VAs (odds ratio: 8,814; 95% CI: 1,943–39,981; p = 0,005), effectiveness of antiarrhythmic therapy (odds ratio: 16,522; 95%CI: 1,959–139,374; p = 0,010) and noninducibility of VAs during procedure (odds ratio: 9,369; 95% CI: 1,400–62,684; 0,021), become predictors of long-term unsuccessful outcomes of CA in pediatric idiopathic VAs.Conclusion. In our study there were identified independent predictors of long-term noneffective CA in children with idiopathic VAs, such as multifocal VAs, effectiveness of antiarrhythmic therapy, and noninducibility of VAs CA. In patients with presence of two or more ventricular foci and the effectivness of antiarrhythmic therapy, prolongate drug therapy may be more preferable.

Anesthetic Management for Ventricular Tachycardia Ablation: A National Anesthesia Clinical Outcomes Registry Analysis

Objectives: We analyzed anesthetic management trends during ventricular tachycardia (VT) ablation, hypothesizing that (1) monitored anesthesia care (MAC) is more commonly used than general anesthesia (GA), (2) MAC use significantly increased after release of the 2019 Expert Consensus Statement on Catheter Ablation of Ventricular Arrhythmias, and (3) anesthetic approach varies based on patient and hospital characteristics. Design: Retrospective study. Setting: National Anesthesia Clinical Outcomes Registry data. Participants: Patients ≥18 years who underwent elective VT ablation between 2013-2021. Interventions: None. Measurements and main results: Covariates were selected a priori within multivariate models, and interrupted time-series analysis was performed. Of the 15,505 patients who underwent VT ablation between 2013-2021, 9,790 (63.1%) received GA. After the 2019 Expert Consensus Statement on Catheter Ablation of Ventricular Arrhythmias supported avoidance of GA, no statistically significant increase in MAC was evident (immediate change in intercept post-consensus statement release AOR 1.41, p=0.1629; change in slope post-consensus statement release AOR 1.06 per quarter, p=0.1591). Multivariate analysis demonstrated that sex, ASA physical status, age, and geographic location were statistically significantly associated with anesthetic approach. Conclusions: GA has remained the primary anesthetic type for VT ablation despite the 2019 Expert Consensus Statement on Catheter Ablation of Ventricular Arrhythmias suggesting its avoidance in idiopathic VT. Achieving widespread clinical practice change is an ongoing challenge in medicine, emphasizing the importance of developing effective implementation strategies to facilitate awareness of guideline release and subsequent adherence to and adoption of recommendations.

Stroke and Bleeding Risks of Endocardial Ablation for Ventricular Arrhythmias

BackgroundRisks of radiofrequency catheter ablation for ventricular arrhythmias include emboli and bleeding complications but data on antithrombotic regimens are limited and guidelines do not specify a systematic approach. ObjectivesThis study sought to assess embolic and bleeding complications in relation to pre-periprocedure and post-periprocedure antithrombotic regimens. MethodsProspective assessment for complications was performed for 663 endocardial radiofrequency catheter ablation procedures in 616 consecutive patients (median age 64 years [Q1-Q3: 54-73 years], 70.3% men, 71.6% with cardiomyopathy, 44.5% with sustained ventricular tachycardia). ResultsThere were 2 strokes (0.3%; 95% CI: 0.0%-0.8%), 1 transient ischemic attack (0.15%), and 2 pulmonary emboli (0.3%). There were 39 bleeding complications (5.9%) including 11 pericardial effusions (1.7%), and 28 related to vascular access (4.2%). Consistent with the prevalence of coronary artery disease (47.5%), atrial fibrillation (30.0%), and prior stroke (10.6%), preprocedure, 464 patients (70.0%) were taking antithrombotic agents including 220 (33.2%) taking aspirin alone (ASA), and 163 (24.6%) taking warfarin or a direct acting oral anticoagulant (DOAC). Preprocedure non-ASA antiplatelet use (OR: 2.846; P = 0.011) and DOAC use (OR: 2.585; P = 0.032) were associated with risk of bleeding complications. Following ablation, 49.8% of patients were treated with ASA 325 mg/d and 30.3% received DOACs or warfarin. New DOAC or warfarin administration was initiated in only 6.6% of patients. Overall, 39.7% of patients continued the same preprocedure antithrombotic regimen. ConclusionsStroke is a rare complication of radiofrequency catheter ablation for ventricular arrhythmia using ASA 325 mg/d as a minimal postprocedure regimen with more potent regimens for selected patients.

How Imaging Techniques Improve Ventricular Arrhythmia Ablation: A Multimodality-Based Approach

Although implantable cardioverter defibrillators offer the best protection against sudden cardiac death, catheter ablation for ventricular arrhythmias (VAs) can modify or prevent this event from occurring. In order to achieve a successful ablation, the correct identification of the underlying arrhythmogenic substrate is mandatory to tailor the pre-procedural planning of an ablative procedure as appropriately as possible. We propose that several of the imaging modalities currently used could be merged, including echocardiography (also intracardiac), cardiac magnetic resonance, cardiac computed tomography, nuclear techniques, and electroanatomic mapping. The aim of this state-of-the-art review is to present the value of each modality, that is, its benefits and limitations, in the assessment of arrhythmogenic substrate. Moreover, VAs can be also idiopathic, and in this paper we will underline the role of these techniques in facilitating the ablative procedure. Finally, a hands-on workflow for approaching such a VA and future perspectives will be presented.