Review Article

Ablation Methods and Catheter Settings for Ventricular Tachycardia Ablation: A Bench to Bedside Review: Part 2

Register or Login to View PDF Permissions
Permissions× For commercial reprint enquiries please contact Springer Healthcare: ReprintsWarehouse@springernature.com.

For permissions and non-commercial reprint enquiries, please visit Copyright.com to start a request.

For author reprints, please email rob.barclay@radcliffe-group.com.
Information image

  • Views: 84

  • Likes: 0

  • Downloads: 31

  • Citations: 1

  • Read time: 28m 20s
Average (ratings)
No ratings
Your rating

Abstract

Catheter ablation remains a cornerstone in the treatment of ventricular tachycardia (VT) in structural heart disease. Part 1 of this review focused on the principles and technical aspects of radiofrequency (RF) ablation. Part 2 explores alternative strategies designed to overcome the limitations of conventional RF, in particular, achieving transmurality in complex or deep intramuscular substrates. We critically evaluate the mechanisms, evidence and clinical applications of bipolar RF ablation, pulsed-field ablation (PFA), ultra-low-temperature cryoablation (ULTC) and venous ethanol and needle ablation. Despite the rapid expansion of the technological armamentarium, current clinical evidence remains limited. The data supporting long-term safety and durability are predominantly based on preclinical and small observational studies. We advocate for continued investigation into these specialised techniques to provide a more tailored, patient-specific approach to VT management.

Keywords

Ventricular tachycardia, catheter ablation, pulsed field ablation, ultra-low-temperature cryoablation,

Received:

Accepted:

Published online:

DOI: https://doi.org/10.15420/aer.2025.74

Disclosure: JS has received an institutional grant from Abbott Medical; consulting fees from ChamberTech and Rhythm AI; honoraria from Abbott Medical, Biotronik and Biosense Webster; travel support from Abbott, Biosense Webster and Medtronic; and has stock in ChamberTech. TD has received grants from Abbott Medical, Catheter Precision and Medtronic, as well as honoraria from Abbott Medical, Johnson & Johnson and Medtronic. All other authors have no conflicts of interest to declare.

Correspondence: Tarvinder Dhanjal, University Hospital of Coventry and Warwickshire, Clifford Bridge Road, Coventry, CV2 2DX, UK. E: tarvinder.dhanjal@warwick.ac.uk

Copyright:

© The Author(s). This work is open access and is licensed under CC-BY-NC 4.0. Users may copy, redistribute and make derivative works for non-commercial purposes, provided the original work is cited correctly.

In part 1 of this review we described the principles and technical considerations of radiofrequency (RF) catheter ablation (RFCA) and the ablation metrics for ventricular tachycardia (VT).1 We focused on catheter designs, including tip size, irrigation and power versus temperature control. We also outlined ablation metrics, including general impedance, local impedance, the force–time integral, the Force–Power–Time Index, ablation index, lesion size index and time after temperature 60°C, explaining how they reflect lesion formation and contribute to safety. One of the main limitations of RF ablation is the inconsistency in achieving transmural lesions. This is particularly evident in the heterogeneous scarred tissue of ischaemic cardiomyopathy (ICM), non-ICM (NICM) and at the left ventricular (LV) summit, the papillary muscles or the moderator band. In addition, ventricular substrate is rarely confined to a single myocardial surface.2 Therefore, familiarity with other ablation strategies is essential. Here, in part 2, we discuss bipolar RF ablation (BRFA), pulsed field ablation (PFA), ultra-low-temperature cryoablation (ULTC), venous ethanol ablation (VEA) and needle-based intramural ablation. These innovations offer the potential to target more complex substrates and form deeper lesions. We also evaluate the level of evidence (Table 1 ), the mechanism, evidence and potential applications of each modality. Most of the data comes from pre-clinical studies. While the results are promising, the practical application of these new technologies may be affected by anatomical complexities and tissue perfusion. Therefore, caution is needed when applying findings from laboratory and animal studies to the varied clinical presentations of VT ablation.

The clinical evidence primarily comes from case reports, case series and small non-randomised trials, with no published randomised controlled trials (RCTs) available. This article synthesises the current landscape of ablation technologies to offer a balanced perspective on their utility.

Methods

A narrative search was conducted across PubMed and Embase, covering the period from the inception until November 2025, using the following terms: (ventricular tachycardia or VT) and (ablation). Key studies are summarised in Table 1. Ex vivo and in silico studies were categorised as bench studies, whereas large-animal studies included in vivo research in dogs, sheep, pigs and cattle. Information for feasibility studies, non-randomised studies, case series, case reports and RCTs is also provided.

Table 1: Level of Evidence for Ablation Methods

Article image
Download

Results and Discussion

Bipolar Radiofrequency Ablation

In a bipolar circuit, the current flows between two linear catheters positioned on opposite sides of the tissue. Unipolar ablation is limited to lesion depths of 5–6 mm. This may be a significant limitation in case of deep substrates, for instance in hypertrophic cardiomyopathy or cardiac amyloidosis.3–5 BRFA has emerged as a promising alternative for patients who have not responded to unipolar ablation approaches, especially in cases where deeper transmural lesions are required. Under ex vivo conditions, acute transmurality can be achieved in wall thicknesses up to 25 mm using a force of 10–20 g and an RF time of 60–120 seconds.6 However, chronic lesions (observed at 12 weeks) may be smaller and less transmural than initially anticipated (maximum depths ranging from 1.9 to 11 mm).7

From a practical standpoint, the bipolar technique uses two unidirectional ablation catheters simultaneously on either side of the target tissue. Unlike unipolar ablation, BRFA does not use a ground pad. Instead, the second ablation catheter is connected to the indifferent electrode port of the RF generator using a custom-made cable or connector box. This second catheter is also connected to an independent (custom-made) irrigation system, because it is not linked to the RF generator’s irrigation pump.8 Both the CARTO (Biosense Webster) and EnSite (Abbott) systems support BRFA and allow for visualisation of the second catheter. In practice, the set-up is typically configured as a unipolar system with the capability to switch to BRFA. BRFA current is delivered uniformly through both catheters, but the current cannot be adjusted independently. Importantly, both catheters should be irrigated independently to prevent char formation. The efficacy of BRFA may be compromised if there is an impedance mismatch between the two environments, such as the presence of epicardial fat on one side. Regarding catheter settings, clinical studies have reported using pulse durations of 60–90 seconds and powers from 10 to 40 W, titrated to achieve a target impedance drop of 20–40 Ω or 10%.9–11 For open-irrigated catheters, the temperature limit was set at 42°C, whereas for catheters equipped with multiple thermocouples, the limit was set at 50°C.10

In terms of clinical applicability, BRFA has been successfully used in patients with ICM, NICM and premature ventricular contractions (PVC).9,10,12,13 The areas targeted for ablation included the septum, free walls, LV summit and outflow tract, with the ablation performed via an endo-epicardial approach. However, use of BRFA for papillary muscle arrhythmias has been limited, likely due to challenges with catheter stability and reduced energy transfer.9,12,14–17 BRFA can be performed either as a redo or de novo procedure.10,14 In terms of effectiveness, the meta-analysis of Farkowski et al. of 12 studies (n=120 patients; including those who had at least one previously failed unipolar RFCA VT ablation and had then undergone BRFA), acute VT non-inducibility was achieved in 88.2% of patients.18 At follow-up, which ranged from 1 to 2 years, the long-term effectiveness of BRFA was found to be 55%. In another study of patients undergoing redo procedures with a combination of unipolar and bipolar ablation methods, 74% of patients experienced acute elimination of clinical VT/PVC, with 61% remaining free from arrhythmia at up to an 8-month follow-up.15 Safety and practical considerations of BRFA are summarised in Tables 2 and 3.

Table 2: Ablation Techniques, Associated Risks and Mitigating Strategies

Article image
Download

Table 3: Ablation Sources for VT Ablation

Article image
Download

Pulsed Field Ablation

PFA is the latest advancement in ablation technology. PFA generates high-energy, short-duration electrical impulses that last for microseconds or nanoseconds, creating lesions through a process known as electroporation. Key parameters for energy delivery include voltage, pulse duration, the number of pulses, pulse frequency and polarity. The primary differences between PFA systems relate to polarity, which affects the depth of tissue impact. Monopolar pulses can penetrate deeper but may result in undesirable effects, such as muscle contractions. In contrast, a biphasic waveform reduces charge accumulation, leading to a more selective PFA effect with less collateral damage compared with monophasic waveforms. In addition, the voltage or current and the number of pulses influence the reversibility of electroporation damage. Variations in PFA technology also include different catheter designs, such as focal, basket or ring options, as well as single versus dual energy capabilities and integration with mapping systems.19 PFA represents a diverse range of technologies, each with unique configurations. One challenge in comparing these systems is that pulse frequency is often proprietary and may not be disclosed. Currently, the parameters that can typically be adjusted in clinical PFA systems are the energy level (voltage or field strength) and the number of pulses delivered per lesion. This limited control can make it difficult to tailor therapy to specific patients.

Initial preclinical histological data from studies in pigs suggest that PFA is selective for cardiomyocytes, causing minimal collateral damage to surrounding tissues.20 Because muscle contractions can occur during PFA delivery, these procedures are usually performed under general anaesthesia, although some published experiences indicate that deep sedation can be a viable alternative.21,22 PFA has demonstrated the ability to create well-defined lesions in the ventricular myocardium. Unlike RFCA, PFA exhibits a phenomenon known as ‘repetition dependency’, where the size of lesions tends to increase with consecutive applications of a similar electrical field. It is important to note that the immediate loss of the bipolar electrogram following PFA does not always indicate successful lesion delivery; rather, it may reflect a state of local myocardial stunning, raising concerns about the durability of the lesions created by PFA.23 Compared with RF ablation, PFA requires minimal irrigation (13 versus 2–3 ml/min, respectively), which can be particularly advantageous in cases of epicardial VT.

In animal studies, PFA appeared to be more effective than RFCA for creating deep lesions in scarred myocardium.24 A study involving a normal swine heart found that the acute mean (± SD) lesion depths were 5.6 ± 1.43 mm after a single application and 9.9 ± 2 mm following four applications.25 At 3–4 weeks after ablation, the chronic lesion depths measured 3.9 ± 0.92 and 7.3 ± 0.83 mm after one and four applications, respectively. Ablation performed on the endocardial aspect of the LV summit near the main coronary branches had no impact on the arteries.25

Furthermore, PFA was found to be superior in creating deep lesions compared with RFCA in scarred myocardium.24 In a swine model of post-MI, PFA lesions penetrated from the subendocardium through collagen and fat to reach the epicardial layers, whereas RFCA lesions were confined to the subendocardium.24 Specifically, PFA produced lesions that were deeper and more transmural than those produced by RFCA (median 6.4 mm [IQR 5.5–7.5] versus 5.4 [IQR 4.8–5.9] mm), with penetration rates of 72% and 30%, respectively (p≤0.02 for each comparison).24 In addition, Sphere-9 (Affera, Medtronic) was used to ablate papillary muscles, the moderator band and epicardial substrates.26 Bipolar PFA was performed with two Sphere-9 catheters, across the right ventricular/LV septum and LV free wall. PFA has also shown promising results in redo ablations after failed RFCA, largely due to the absence of cellular regeneration that can occur with RFCA.25

Currently available PFA systems used for ventricular ablation include the Affera, Farapulse (Boston Scientific), Galaxy Centauri (CardioFocus) and FieldForce (Field Medical). The Affera system delivers bipolar pulses with a biphasic waveform, achieving voltages of up to 2 kV over approximately 0.25 seconds and operates independently of ECG synchronisation.27 The Farapulse system also delivers bipolar pulses with a biphasic waveform, but has a voltage range between 1.8 and 2 kV and lasts for 2.5 seconds; this system is synchronised with the ECG.28 The Centauri system provides monopolar pulses of a biphasic waveform with a current of up to 25 A. It is synchronised with the ECG and compatible with TactiCath SE (Abbott), StablePoint (Boston Scientific) and ThermoCool ST (Biosense Webster) linear catheters.29 The FieldForce system can deliver both bipolar and monopolar pulses, featuring a biphasic waveform and voltages exceeding 10 kV over less than 0.2 seconds. This system is synchronised with the ECG and can detect contact force.30 When comparing PFA data from different manufacturers, it is important to exercise caution due to proprietary differences.

In the literature, reports of clinical experiences with these systems are limited to case reports, small observational studies and non-randomised studies. Peichl et al. reported a feasibility human study using the Affera system in a cohort primarily consisting of VT in the context of ICM (n=18).27 In that study, initial lesions were created with RF, which were then consolidated with up to three 5-second PFA applications. Following ablation, 89% of patients achieved non-inducibility of VT and 78% were free from ventricular arrhythmias at 3 months.27 The Affera system is currently being evaluated in a feasibility study (NCT06703489), with an estimated completion date of June 2026. As for the Farapulse system, existing literature mostly comprises case reports involving outflow tract PVCs, monomorphic VT in patients with Ebstein’s anomaly and structural heart conditions.31–36 The Centauri system has been evaluated in smaller studies focusing on patients with PVCs and VT, including VT with septal substrate in dilated cardiomyopathy.37 At 3 months, 81–82% of patients showed suppression of PVCs, whereas 52% were free from VT.38,39 The VCAS (n=28) provided feasibility data on the FieldForce system for both endocardial and epicardial VT ablation in patients with ICM and NICM and demonstrated transmurality in a select cohort, with 93% of patients experiencing acute procedural success and 82% remaining arrhythmia-free at the 180-day follow-up.30 Other ongoing clinical trials include a study assessing the Farapoint system (NCT06747013; estimated completion December 2026) and another evaluating the Trupulse system (NCT06816368; estimated completion date August 2026). The PFA arena still lacks RCTs and long-term and efficacy data, and lesion durability remains unproven. Safety and practical considerations related to PFA can be found in Tables 2 and 3.

Cryoablation and Ultra-Low-Temperature Cryoablation

The use of cryoablation has been studied in animal models. In a study conducted by Khairy et al. in a swine model, cryoablation was applied at a mean temperature of 79.9 ± 4.0°C.40 The findings of that study indicated that lower temperatures resulted in lesions with a larger surface area and volume, but the depth of the lesions was unchanged.40 The lesions were well defined, preserving intact endothelial layers without any signs of thrombus formation. Other studies have identified a freeze duration of 3 minutes as the optimal treatment time because no additional benefits were observed with longer exposure.41,42 To create continuous ablation zones, lesions must overlap by at least 2.5 mm.41 In an ex vivo porcine study, researchers compared RF ablation (using an irrigated ThermoCool catheter at 25 W, titrated to 50 W over 90 seconds) to cryoablation (at −75°C for 300 seconds).43 Lesion size was affected by factors such as electrode orientation, blood flow and contact pressure. Notably, cryoablation performed in a horizontal orientation produced the largest lesions (depth 10.3 ± 1.0 mm and volume 961 ± 103 mm4) compared with RF under the same conditions (depth 6.3 ± 0.5 mm and volume 245 ± 22 mm4; both p<0.05).43 Although cryoablation consistently resulted in larger lesion volumes in the horizontal orientation, RF produced equal or larger volumes in the vertical position (all p<0.05).43

From a clinical perspective, cryoablation appears to trigger less atomicity compared with RFCA and provides enhanced adhesive stability. This characteristic has proven beneficial for ablation procedures involving papillary muscle or the moderator band.44,45 Furthermore, cryoablation has demonstrated both acute and chronic efficacy in reducing the recurrence of ventricular arrhythmias, while potentially minimising the risk of collateral injury.44–46 Cryoablation may also serve as a safer alternative to RF for lesions located within 2 mm of coronary arteries.46 ULTC may offer potential advantages for VT ablation over conventional cryoablation and RF techniques. ULTC uses near-critical nitrogen refrigerant near its boiling temperature of −196°C.47 This near-critical nitrogen combines the flow properties of gas with the density and thermal capacity of liquid, enabling uninterrupted injection through small lumen catheters. In preclinical models, ULTC produced lesions that could be titrated from 4 to over 10 mm in depth and it could penetrate chronic scar.48 The vCLAS catheter (Adagio Medical) features a 9 Fr, bidirectionally deflectable shaft (diameter 50 mm, deflection >180°) and a solid 15 mm long cryoablation element with eight 1 mm electrodes for pacing and electrogram recording. The depths and lateral dimensions of the lesions depend on the duration of the freeze–thaw–freeze cycle. Studies in swine models have shown promising results.48–50

In terms of clinical experience, the CryoCure-VT trial, involving 64 patients, 78.1% of whom had structural disease, was the first human trial assessing this technology.47 That study demonstrated 90% acute elimination of clinical VT and 85% elimination of all inducible VTs.47 At 6 months, 60% of patients had no VT recurrence, whereas the freedom from ICD shock was 81%.47 As part of the CryoCure-VT study, Dinov et al. evaluated the acute effectiveness of a new ULTC technology by examining postinterventional cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE).51 In that study, post-procedural CMR revealed new LGE with up to 75% transmurality in five of six patients.51 The results of FULCRUM-VT (NCT05675865), a prospective multicentre single-arm study enrolling 206 patients with structural heart disease (both ICM and NICM), are awaited. Adagio vCLAS has already received CE Mark approval in Europe and US Food and Drug Administration (FDA) Breakthrough Device designation in the US for treatment of drug-refractory monomorphic VT in ICM and NICM. However, it is essential to note that the Adagio system is still at an early phase and clinical experience is limited. Safety and practical considerations of cryoablation and ULTC are summarised in Tables 2 and 3.

Venous Ethanol Ablation

Ethanol ablation has emerged as a valuable technique for treating VT, particularly in situations where conventional catheter-based RFCA is ineffective or challenging. This is often true for patients with complex anatomy or tissues in the basal interventricular septum or at the LV summit. VEA involves infusing ethanol into the cardiac veins to target the arrhythmogenic substrates. The integration of 3D mapping with venography data is vital for accurately identifying suitable veins. This is typically achieved by inserting multipolar catheters into the veins to create a separate independent vein geometry.52 Case reports have described successful treatment of RFCA-resistant VT, including patients with hypertrophic cardiomyopathy.53–57 Ethanol ablation has also been successfully performed to treat VT with cannulation of coronary artery branches.58

Valderrábano et al. conducted VEA in 44 consecutive patients with ablation-refractory VT from various aetiologies.52 Both endocardial and epicardial veins were selected based on the substrate, with multiple veins targeted in 14 patients. At 1 year, the success rate for eliminating arrhythmia was 84.1%. Larger studies are awaited and the VELVET trial (NCT05511246) is currently recruiting. VELVET is a comparative effectiveness RCT comparing endocardial RFCA alone versus RFCA combined with venous ethanol in patients with ischaemic VT. VEA remains a complex procedure associated with relatively prolonged procedure times, fluoroscopy and contrast use. Safety and practical considerations of VEA are summarised in Tables 2 and 3.

Needle Ablation

Needle ablation is another emerging technique for deep intramyocardial substrate that is not reachable by standard ablation methods. Saline-enhanced RF uses the Thermedical Ablation System (Thermedical) and Durablate catheter. The catheter incorporates a 25 G stainless steel needle. That needle is inserted into the myocardium. Once the position has been confirmed, heated saline (up to 60°C) is delivered to the tissue at a flow rate of 10 ml/min. At the same time, the system delivers RF with energy up to 50 W. This approach uses the principle that heated saline injection markedly increases convective heat transport during RF application.

Packer et al. published the results of a first-in-human study on this method; the study cohort (n=32) included both ICM and NICM patients (56% and 44%, respectively) and all the patients had undergone at least one prior catheter ablation.59 Packer et al. reported an acute procedural success rate of 97% for eliminating clinical VT. At a mean follow-up of 5 months (n=32), device therapies were reduced by 89%. The prototype for saline-enhanced RF was a needle ablation method using a conventional ablation catheter (Surround Flow; Biosense Webster) equipped with a 27 G extendable needle (up to 10 mm) and a separate irrigation system. The method was first described by Sapp et al. and was subsequently tested by Stevenson et al. in 31 patients.60,61 The method resulted in a freedom from arrhythmia rate of 48%, with a significant reduction in VT burden in 19% of patients at 6-month follow-up.61 Needle ablation is still considered a specialised approach and there is an urgent need for prospective multicentre trials to further investigate its safety and effectiveness. Safety and practical considerations of needle ablation are summarised in Tables 2 and 3.

Conclusion

Long-term success rates for VT ablation in structural heart disease remain modest, with a greater challenge in patients with NICM. RCTs comparing medical therapy to ablation report VT recurrence rates ranging from 27% to 62%. The ablation procedure consists of two major components: first, defining the VT substrate using optimal mapping methods; and, second, effectively eliminating the arrhythmogenic substrate through ablation. Considerable progress has been made in refining the mapping process. There is a consistent temporal trend of emerging mapping techniques with greater diagnostic accuracy, improvements in multipolar mapping catheter design and electroanatomical map functions with enhanced electrogram feature analysis. Indeed, the VT recurrence rates in studies evaluating novel mapping methods, including isochronal late activation map, decrement evoked potentials, ventricular electrogram duration map and peak frequency, are reported to be between 20% and 30%.62–65 This review highlights the limited availability of clinical data to guide VT operators when using an array of technologies to perform the ablation part of the procedure. Consistent across the range of ablation methods are preclinical studies performed using ex vivo ventricular myocardium. However, only a limited number of technologies have used specific preclinical structural heart disease models to represent the range of biological substrates encountered, such as post-MI VT. Furthermore, there is a lack of ablation metric guidance related to the various anatomical components of the ventricles. For example, the metrics enabling the delivery of safe and effective lesions at the interventricular septum are likely to differ at the LV outflow tract. Most of the available ablation technologies primarily provide human feasibility data specific to VT ablation. However, with the exception of power-controlled RF ablation, large multicentre studies evaluating specific ablation technologies or ablation metrics are lacking. The durability of most alternative energy modalities remains unproven.

In addition to ensuring the efficacy of procedures, it is essential to focus on reducing procedure time. The integration of preprocedural imaging techniques, such as CT or MRI, along with computational modelling, can significantly shorten the time required for 3D map acquisition. Traditional point-by-point techniques are often limited by small lesion sizes and inconsistent lesion quality, which can undermine their effectiveness. To enhance both speed and efficacy, systems that integrate various technical approaches should be prioritised. Dual-energy technologies, including RF and PFA, could provide improved precision and time efficiency. The dual-energy ThermoCool SmartTouch SF catheter has received CE mark approval in Europe and is currently under investigation in the US. Another promising development is the Abbott Volt system, which combines high-density mapping with efficient ablation and has already received CE mark and FDA approval. In addition, the Medtronic Affera platform integrates dual-energy ablation and high-density mapping into a single system and is already CE marked and FDA approved. It is important to emphasise that the evidence for the dual-energy system remains limited, with RCTs, longitudinal data, head-to-head comparisons, cost-effectiveness and safety surveillance lacking. In summary, the future of VT ablation lies in integrated, high-efficiency technologies that optimise procedural speed without compromising effectiveness.

VT ablation remains a challenging procedure. Advances in mapping techniques and ablation energy sources show promise in improving efficacy and clinical outcomes. Large-scale RCTs are essential to provide further guidance on the use and application of the technology.

Clinical Perspective

  • Although standard RF ablation is effective for many patients, a significant clinical challenge remains in treating deep intramural or epicardial substrates.
  • The choice of ablation modality should be increasingly personalised, matching the specific biophysical properties of the energy source (e.g. the depth of ULTC or the speed of PFA) to the unique anatomical and substrate requirements of the individual patient.
  • Emerging modalities like PFA offer the potential for improved safety profiles through tissue-selective electroporation, potentially reducing the risk of collateral damage to coronary arteries or the conduction system compared with thermal-based methods.
  • Despite the promising nature of these technologies, the transition from ‘bench to bedside’ is currently supported primarily by preclinical data and small observational series. Operators must exercise clinical judgment when applying these specialised techniques, because long-term durability and standardised procedural protocols are still being established.

References

  1. Niespialowska-Steuden M, Silberbauer J, Al-Sheikhli J, et al. Ablation methods and catheter settings for ventricular tachycardia ablation: a bench to bedside review: part 1. Arrhythm Electrophysiol Rev 2026;15:e18. 
    Crossref
  2. Ravi V, Winterfield J, Liang J, et al. Solving the reach problem: a review of present and future approaches for addressing ventricular arrhythmias arising from deep substrate. Arrhythm Electrophysiol Rev 2023;12:e04. 
    Crossref | PubMed
  3. Themistoclakis S, Calzolari V, De Mattia L, et al. In vivo lesion index (LSI) validation in percutaneous radiofrequency catheter ablation. J Cardiovasc Electrophysiol 2022;33:874–82. 
    Crossref | PubMed
  4. Compagnucci P, Dello Russo A, Gasperetti A, et al. Substrate characterization and outcomes of ventricular tachycardia ablation in amyloid cardiomyopathy: a multicenter study. Circ Arrhythm Electrophysiol 2024;17:e012788. 
    Crossref | PubMed
  5. Casella M, Compagnucci P, Ciliberti G, et al. Characteristics and clinical value of electroanatomic voltage mapping in cardiac amyloidosis. Can J Cardiol 2024;40:372–84. 
    Crossref | PubMed
  6. Koruth JS, Dukkipati S, Miller MA, et al. Bipolar irrigated radiofrequency ablation: a therapeutic option for refractory intramural atrial and ventricular tachycardia circuits. Heart Rhythm 2012;9:1932–41. 
    Crossref | PubMed
  7. Derejko P, Janus I, Kułakowski P, et al. Bipolar endo-epicardial RF ablation: animal feasibility study. Heart Rhythm 2024;21:790–8. 
    Crossref | PubMed
  8. Nakajima K, Zweiker D, Spartalis M, et al. Bipolar radiofrequency catheter ablation for ventricular arrhythmias. Rev Cardiovasc Med 2022;23:179. 
    Crossref | PubMed
  9. Della Bella P, Peretto G, Paglino G, et al. Bipolar radiofrequency ablation for ventricular tachycardias originating from the interventricular septum: safety and efficacy in a pilot cohort study. Heart Rhythm 2020;17:2111–8. 
    Crossref | PubMed
  10. Futyma P, Sultan A, Zarębski Ł, et al. Bipolar radiofrequency ablation of refractory ventricular arrhythmias: results from a multicentre network. Europace 2024;26:euae248. 
    Crossref | PubMed
  11. Futyma P, Ciąpała K, Sander J, et al. Bipolar radiofrequency ablation of ventricular arrhythmias originating in the vicinity of His bundle. Circ Arrhythm Electrophysiol 2020;13:e008165. 
    Crossref | PubMed
  12. Caixal G, Waight M, Pinto A, et al. Safety and efficacy of bipolar radiofrequency catheter ablation in ventricular arrhythmias of mural vs non-mural origin. Europace 2023;25(Suppl 1):euad122.342. 
    Crossref
  13. Derejko P, Kuśnierz J, Bardyszewski A, et al. Bipolar endo-epicardial radiofrequency ablation of therapy-resistant ventricular arrhythmias: a brief case series. JACC Clin Electrophysiol 2023;9:733–7. 
    Crossref | PubMed
  14. Moser F, Maslova V, Zaman A, et al. Bipolar catheter ablation as a key for successful treatment of intramural ventricular arrhythmias: results from the Bipolar-Kiel study. J Cardiovasc Electrophysiol 2025;36:2797–807. 
    Crossref | PubMed
  15. Futyma P, Sander J, Ciąpała K, et al. Bipolar radiofrequency ablation delivered from coronary veins and adjacent endocardium for treatment of refractory left ventricular summit arrhythmias. J Interv Card Electrophysiol 2020;58:307–13. 
    Crossref | PubMed
  16. Futyma P, Santangeli P, Pürerfellner H, et al. Anatomic approach with bipolar ablation between the left pulmonic cusp and left ventricular outflow tract for left ventricular summit arrhythmias. Heart Rhythm 2020;17:1519–27. 
    Crossref | PubMed
  17. Teh AW, Reddy VY, Koruth JS, et al. Bipolar radiofrequency catheter ablation for refractory ventricular outflow tract arrhythmias. J Cardiovasc Electrophysiol 2014;25:1093–9. 
    Crossref | PubMed
  18. Farkowski M, Truszkowska N, Zielinska A, et al. Effectiveness and safety of bipolar ablation of heart arrhythmia. A systematic review with meta-analysis. EP Europace 2022;24(Suppl 1). 
    Crossref
  19. Li H, Zhang H, Tian M, et al. Pulsed field ablation for ventricular arrhythmias: from mechanistic foundations to clinical translation. Heart Rhythm 2026;7:171–82. 
    Crossref
  20. Wittkampf FHM, van Driel VJ, van Wessel H, et al. Myocardial lesion depth with circular electroporation ablation. Circ Arrhythm Electrophysiol 2012;5:581–6. 
    Crossref | PubMed
  21. Grimaldi M, Quadrini F, Caporusso N, et al. Deep sedation protocol during atrial fibrillation ablation using a novel variable-loop biphasic pulsed field ablation catheter. Europace 2023;25(Suppl 1):euad222. 
    Crossref | PubMed
  22. Galuszka OM, Kueffer T, Madaffari A, et al. Comparison of the feasibility and safety of a deep sedation protocol for pulmonary vein isolation with pulsed field ablation, cryoballoon ablation, and radiofrequency ablation. J Am Heart Assoc 2024;13:e033210. 
    Crossref | PubMed
  23. Mountantonakis S, Beccarino N, Abrams M, et al. Methods and techniques to optimize energy delivery using the circular array pulsed field ablation catheter. Heart Rhythm 2025;22:e74–84. 
    Crossref | PubMed
  24. Younis A, Zilberman I, Krywanczyk A, et al. Effect of pulsed-field and radiofrequency ablation on heterogeneous ventricular scar in a swine model of healed myocardial infarction. Circ Arrhythm Electrophysiol 2022;15:e011209. 
    Crossref | PubMed
  25. Yavin HD, Higuchi K, Sroubek J, et al. Pulsed-field ablation in ventricular myocardium using a focal catheter: the impact of application repetition on lesion dimensions. Circ Arrhythm Electrophysiol 2021;14:e010375. 
    Crossref | PubMed
  26. Nies M, Watanabe K, Kawamura I, et al. Preclinical study of pulsed field ablation of difficult ventricular targets: intracavitary mobile structures, interventricular septum, and left ventricular free wall. Circ Arrhythm Electrophysiol 2024;17:e012734. 
    Crossref | PubMed
  27. Peichl P, Wichterle D, Schlosser F, et al. Mapping and ablation of ventricular tachycardia using dual-energy lattice-tip focal catheter: early feasibility and safety study. Europace 2024;26:euae275. 
    Crossref | PubMed
  28. Reddy VY, Neuzil P, Koruth JS, et al. Pulsed field ablation for pulmonary vein isolation in atrial fibrillation. J Am Coll Cardiol 2019;74:315–26. 
    Crossref | PubMed
  29. Anić A, Phlips T, Brešković T, et al. Pulsed field ablation using focal contact force-sensing catheters for treatment of atrial fibrillation: acute and 90-day invasive remapping results. Europace 2023;25:euad147. 
    Crossref | PubMed
  30. Reddy VY, Koruth JS, Peichl P, et al. High-voltage focal pulsed field ablation to treat scar-related ventricular tachycardia: the first-in-human VCAS trial. Circulation 2025;152:1691–704. 
    Crossref | PubMed
  31. Schmidt B, Chen S, Tohoku S, et al. Single shot electroporation of premature ventricular contractions from the right ventricular outflow tract. Europace 2022;24:597. 
    Crossref | PubMed
  32. Krause U, Bergau L, Zabel M, et al. Flowerpower: pulsed field ablation of ventricular tachycardia in a patient with Ebstein’s anomaly. Eur Heart J Case Rep 2023;7:ytad093. 
    Crossref | PubMed
  33. Ouss A, van Stratum L, van der Voort P, Dekker L. First in human pulsed field ablation to treat scar-related ventricular tachycardia in ischemic heart disease: a case report. J Interv Card Electrophysiol 2023;66:509–10. 
    Crossref | PubMed
  34. Katrapati P, Weiss JP, Baning D, et al. Pulsed field ablation for incessant scar-related ventricular tachycardia: first US report. Heart Rhythm 2024;21:1236–9. 
    Crossref | PubMed
  35. Lozano-Granero C, Hirokami J, Franco E, et al. Case series of ventricular tachycardia ablation with pulsed-field ablation: pushing technology further (into the ventricle). JACC Clin Electrophysiol 2023;9:1990–4. 
    Crossref | PubMed
  36. Qiu J, Dai M, Bai Y, Chen G. Potential application of pulsed field ablation in ventricular arrhythmias. Medicina (Kaunas) 2023;59:723. 
    Crossref | PubMed
  37. Compagnucci P, Valeri Y, Conti S, et al. Technological advances in ventricular tachycardia catheter ablation: the relentless quest for novel solutions to old problems. J Interv Card Electrophysiol 2024;67:855–64. 
    Crossref | PubMed
  38. Peichl P, Bulava A, Wichterle D, et al. Efficacy and safety of focal pulsed-field ablation for ventricular arrhythmias: two-centre experience. Europace 2024;26:euae192. 
    Crossref | PubMed
  39. Della Rocca DG, Cespón-Fernández M, Keelani A, et al. Focal pulsed field ablation for premature ventricular contractions: a multicenter experience. Circ Arrhythm Electrophysiol 2024;17:e012826. 
    Crossref | PubMed
  40. Khairy P, Rivard L, Guerra PG, et al. Morphometric ablation lesion characteristics comparing 4, 6, and 8 mm electrode-tip cryocatheters. J Cardiovasc Electrophysiol 2008;19:1203–7. 
    Crossref | PubMed
  41. Hunt GB, Chard RB, Johnson DC, Ross DL. Comparison of early and late dimensions and arrhythmogenicity of cryolesions in the normothermic canine heart. J Thorac Cardiovasc Surg 1989;97:313–8. 
    Crossref | PubMed
  42. Hayase J, Fishbein G, Rerkpichaisuth V, et al. Linear epicardial cryoablation effects in a porcine model: lesion characteristics and vascular risk. J Cardiovasc Electrophysiol 2023;34:1878–84. 
    Crossref | PubMed
  43. Parvez B, Pathak V, Schubert CM, Wood M. Comparison of lesion sizes produced by cryoablation and open irrigation radiofrequency ablation catheters. J Cardiovasc Electrophysiol 2008;19:528–34. 
    Crossref | PubMed
  44. Whitaker J, Batnyam U, Kapur S, et al. Safety and efficacy of cryoablation for right ventricular moderator band-papillary muscle complex ventricular arrhythmias. JACC Clin Electrophysiol 2022;8:857–68. 
    Crossref | PubMed
  45. Cook C, Welter-Frost A, Wilson DR, Herweg B. Cryoballoon ablation for refractory ventricular tachycardia. HeartRhythm Case Rep 2022;9:203–7. 
    Crossref | PubMed
  46. Ghannam M, Chugh A, Thomas M, et al. Cryoablation for the treatment of ventricular tachycardia in close proximity to coronary arteries. HeartRhythm Case Rep 2022;8:707–10. 
    Crossref | PubMed
  47. Verma A, Essebag V, Neuzil P, et al. Cryocure-VT: the safety and effectiveness of ultra-low-temperature cryoablation of monomorphic ventricular tachycardia in patients with ischaemic and non-ischaemic cardiomyopathies. Europace 2024;26:euae076. 
    Crossref | PubMed
  48. Bourier F, Takigawa M, Lam A, et al. Ultralow temperature cryoablation: safety and efficacy of preclinical atrial and ventricular lesions. J Cardiovasc Electrophysiol 2021;32:570–7. 
    Crossref | PubMed
  49. Dewland TA, Higuchi S, Venkateswaran R, et al. MP-483493-006 ultra-low temperature cryoablation versus ultra-low temperature cryoablation combined with pulsed field ablation in a swine ventricular infarct model. Heart Rhythm 2024;21(Suppl 76):S76. 
    Crossref
  50. Liuba I, Younis A, Sperling J, et al. Efficacy of balloon-expandable extreme-low-temperature ventricular epicardial cryoablation: a preclinical proof of concept evaluation. Heart Rhythm 2024;22:e183–91. 
    Crossref | PubMed
  51. Dinov B, Dilk P, Paetsch I, et al. Cryoablation of ventricular tachycardia using ultra-low temperature technology: acute success and insights from the post-interventional CMR. Europace 2024;26(Suppl 1):euae102.322. 
    Crossref
  52. Valderrábano M, Fuentes Rojas SC, Lador A, et al. Substrate ablation by multivein, multiballoon coronary venous ethanol for refractory ventricular tachycardia in structural heart disease. Circulation 2022;146:1644–56. 
    Crossref | PubMed
  53. Weinand N, Thind M, Pomerantz B, et al. Retrograde coronary venous ethanol ablation for ventricular tachycardia in a patient with inaccessible substrate due to previous surgery. J Cardiovasc Electrophysiol 2024;35:1893–6. 
    Crossref | PubMed
  54. De Smet MAJ, Tavernier R, Duytschaever M, et al. Rescue retrograde coronary venous ethanol ablation of ventricular tachycardia storm in a patient with lamin A/C cardiomyopathy: a case report. Eur Heart J Case Rep 2024;8:ytae235. 
    Crossref | PubMed
  55. Tavares L, Lador A, Fuentes S, et al. Intramural venous ethanol infusion for refractory ventricular arrhythmias: outcomes of a multicenter experience. JACC Clin Electrophysiol 2020;6:1420–31. 
    Crossref | PubMed
  56. Topaloglu S, Vurgun VK, Korkmaz A, et al. Simultaneous ablation of ventricular tachycardia and hemodynamic improvement of mid-ventricular obstructive hypertrophic cardiomyopathy by coronary venous ethanol ablation. J Innov Card Rhythm Manag 2024;15:5903–7. 
    Crossref | PubMed
  57. Xia ET, Lee K, Minga I, et al. Concomitant treatment of sustained ventricular tachycardia and hypertrophic cardiomyopathy with transcoronary ethanol ablation: a case report. Eur Heart J Case Rep 2023;8:ytad632. 
    Crossref | PubMed
  58. Chiba S, Abe M, Nakamura K, Uehara H. Transcoronary mapping using a guidewire during transcoronary ethanol ablation for ventricular tachycardia with a deep intramural substrate: a case report. Eur Heart J Case Rep 2023;7:ytad379. 
    Crossref | PubMed
  59. Packer DL, Wilber DJ, Kapa S, et al. Ablation of refractory ventricular tachycardia using intramyocardial needle delivered heated saline-enhanced radiofrequency energy: a first-in-man feasibility trial. Circ Arrhythm Electrophysiol 2022;15:e010347. 
    Crossref | PubMed
  60. Sapp JL, Beeckler C, Pike R, et al. Initial human feasibility of infusion needle catheter ablation for refractory ventricular tachycardia. Circulation 2013;128:2289–95. 
    Crossref | PubMed
  61. Stevenson WG, Tedrow UB, Reddy V, et al. Infusion needle radiofrequency ablation for treatment of refractory ventricular arrhythmias. J Am Coll Cardiol 2019;73:1413–25. 
    Crossref | PubMed
  62. Aziz Z, Shatz D, Raiman M, et al. Targeted ablation of ventricular tachycardia guided by wavefront discontinuities during sinus rhythm: a new functional substrate mapping strategy. Circulation 2019;140:1383–97. 
    Crossref | PubMed
  63. Al-Sheikhli J, Winter J, Roca-Luque IR, et al. Optimization of decrementing evoked potential mapping for functional substrate identification in ischaemic ventricular tachycardia ablation. Europace 2023;25:euad092. 
    Crossref | PubMed
  64. Rossi P, Cauti FM, Niscola M, et al. Ventricular electrograms duration map to detect ventricular arrhythmia substrate: the VEDUM project study. Circ Arrhythm Electrophysiol 2023;16:447–55. 
    Crossref | PubMed
  65. Mayer J, Al-Sheikhli J, Niespialowska-Steuden M, et al. Detailed analysis of electrogram peak frequency to guide ventricular tachycardia substrate mapping. Europace 2024;26:euae253. 
    Crossref | PubMed
  66. Kovoor P, Daly M, Pouliopoulos J, et al. Comparison of unipolar versus bipolar ablation and single electrode control versus simultaneous multielectrode temperature control. J Interv Card Electrophysiol 2007;19:85–93. 
    Crossref | PubMed
  67. Yang J, Liang J, Shirai Y, et al. Outcomes of simultaneous unipolar radiofrequency catheter ablation for intramural septal ventricular tachycardia in nonischemic cardiomyopathy. Heart Rhythm 2019;16:863–70. 
    Crossref | PubMed
  68. Nguyen DT, Tzou WS, Brunnquell M, et al. Clinical and biophysical evaluation of variable bipolar configurations during radiofrequency ablation for treatment of ventricular arrhythmias. Heart Rhythm 2016;13:2161–71. 
    Crossref | PubMed
  69. Nguyen DT, Zheng L, Zipse MM, et al. Bipolar radiofrequency ablation creates different lesion characteristics compared to simultaneous unipolar ablation. J Cardiovasc Electrophysiol 2019;30:2960–7. 
    Crossref | PubMed
  70. Shapira-Daniels A, Barkagan M, Yavin H, et al. Novel irrigated temperature-controlled lattice ablation catheter for ventricular ablation: a preclinical multimodality biophysical characterization. Circ Arrhythm Electrophysiol 2019;12:e007661. 
    Crossref | PubMed
  71. Younis A, Zilberman I, Yavin H, et al. Utility and limitations of ablation index for guiding therapy in ventricular myocardium. JACC Clin Electrophysiol 2023;9:1668–80. 
    Crossref | PubMed
  72. Koruth JS, Kuroki K, Iwasawa J, et al. Endocardial ventricular pulsed field ablation: a proof-of-concept preclinical evaluation. Europace 2020;22:434–9. 
    Crossref | PubMed
  73. Verma A, Feld GK, Cox JL, et al. Combined pulsed field ablation with ultra-low temperature cryoablation: a preclinical experience. J Cardiovasc Electrophysiol 2023;34:2124–33. 
    Crossref | PubMed
  74. Younis A, Buck E, Santangeli P, et al. Efficacy of pulsed field vs radiofrequency for the reablation of chronic radiofrequency ablation substrate: redo pulsed field ablation. JACC Clin Electrophysiol 2024;10:222–34. 
    Crossref | PubMed
  75. De Potter T, Balt JC, Boersma L, et al. First-in-human experience with ultra-low temperature cryoablation for monomorphic ventricular tachycardia. JACC Clin Electrophysiol 2023;9:686–91. 
    Crossref | PubMed
  76. Sanchez-Somonte P, Verma A, Da Rosa LB, et al. Ultra-low-temperature cryoablation for ventricular tachycardia: an early single-centre report of acute results. CJC Open 2024;6:560–8. 
    Crossref | PubMed
  77. Haines DE, Verow AF, Sinusas AJ, et al. Intracoronary ethanol ablation in swine: characterization of myocardial injury in target and remote vascular beds. J Cardiovasc Electrophysiol 1994;5:41–9. 
    Crossref | PubMed
  78. Guo L-S, Zhou X, Li Y-H, et al. Alcohol ablation at the posterior papillary muscle prevents ventricular fibrillation in swine without affecting mitral valve function. Europace 2010;12:1781–6. 
    Crossref | PubMed
  79. Kreidieh B, Rodríguez-Mañero M, Schurmann P, et al. Retrograde coronary venous ethanol infusion for ablation of refractory ventricular tachycardia. Circ Arrhythm Electrophysiol 2016;9. 
    Crossref | PubMed
  80. Sapp JL, Cooper JM, Soejima K, et al. Deep myocardial ablation lesions can be created with a retractable needle-tipped catheter. Pacing Clin Electrophysiol 2004;27:594–9. 
    Crossref | PubMed
  81. Sapp JL, Cooper JM, Zei P, Stevenson WG. Large radiofrequency ablation lesions can be created with a retractable infusion-needle catheter. J Cardiovasc Electrophysiol 2006;17:657–61. 
    Crossref | PubMed
Previous Volume Article Next Volume Article