Ventricular PFA
Definition
Ventricular pulsed field ablation is the delivery of electroporation energy to ventricular myocardium to treat ventricular tachycardia, premature ventricular complexes or ventricular fibrillation. It differs from atrial PFA in one decisive respect: the ventricular wall is thick and often scarred or fatty, and PFA's lesion depth plateaus at roughly 6–8 mm regardless of waveform or catheter design — below what is needed for transmurality across much of the left ventricle. (sources/pfa-af-ehra-2026, rating: very high) Every clinical and technical development in this field is an attempt to escape that ceiling: larger tips, higher voltage, repeated applications, epicardial delivery, sequential RF-plus-PF, and bipolar ablation between two catheters.
Key Concepts
The mechanism, tissue selectivity, device classification and platform specifications are common to atrial and ventricular use and are set out in concepts/PFA-Atrial-Arrhythmias. What follows is specific to ventricular delivery.
Why the ventricle is different
- The rationale for PFA in the atrium — tissue selectivity and speed — carries over, and preclinical work showed PFA remains effective within and around infarcted substrate and partially spares endothelium, arterioles, nerve fascicles and pericardial tissue. (sources/pfa-vt-case-series-jacep-2023, rating: low)
- Preclinical and clinical experience converge on a depth ceiling of ≈6–8 mm for monopolar ventricular PFA across technologies, and 6.0 ± 1.2 mm specifically for basket PFA catheters in scarred ventricular tissue. (sources/pfa-af-ehra-2026, rating: very high) (sources/pfa-vt-case-series-jacep-2023)
- Consequences for practice: endocardial monopolar PFA can eliminate endocardial circuits and abolish late potentials but cannot reliably reach an epicardial or midmyocardial circuit, even across the thin right ventricular wall. (sources/pfa-vt-case-series-jacep-2023)
First clinical experience — off-label atrial catheters
Three cases treated with the 31-mm pentaspline Farawave catheter at 2.0 kV bipolar dosing:
- A small, mappable lateral-wall substrate in a preserved-ejection-fraction ventricle: 9 applications abolished late potentials and pace capture and created new dense scar (<0.5 mV).
- A large LV aneurysm causing VT storm after two failed RF ablations: 18 applications delivered during VT terminated the tachycardia at the fifth application and rendered it non-inducible.
- Arrhythmogenic cardiomyopathy with an epicardial circuit: 12 endocardial applications created dense scar (<0.1 mV) but VT was re-induced; only epicardial radiofrequency terminated it.
Electrogram amplitude fell 30% after one application and 56% after a full set — a modest attenuation consistent with a non-transmural lesion. Repetition dependence was evident in all three cases, and VT termination during PFA may reflect capture of a large myocardial mass rather than circuit elimination. (All: sources/pfa-vt-case-series-jacep-2023)
Preclinical strategies to increase depth
In 14 swine using the 9-mm lattice tip with repeated 5.5-second applications:
| Target | Technique | Dimensions (L × W × D) | Transmurality |
|---|---|---|---|
| Papillary muscle (stable contact, n=9) | Monopolar, 3–5 applications | 18.3 × 15.3 × 5.8 mm | Confined to muscle; chordae intact, no MR at 21 days |
| Papillary muscle (intermittent contact, n=4) | Monopolar | 18.8 × 12.7 × 3.9 mm (P=0.014 vs stable) | Extension into adjacent myocardium |
| Moderator band (n=2) | Monopolar, 3 and 5 applications | 19.5–24.0 × 13.5–15.3 × 5.1–6.1 mm | Transmural, including insertion sites |
| Epicardium (n=10) | Monopolar, 4–5 applications | 30.4 × 23.5 × 9.1 mm | 2/10 (20%) |
| Septum / LV free wall (n=12) | Bipolar, two tips, 4–7 applications | 29.6 × 21.0 × 14.3 mm | 13/15 (87%; P=0.002 vs epicardial) |
- Bipolar PFA is the most effective depth strategy tested: the deepest lesion reached 21.3 mm, one lesion was transmural across an 11.1 mm septum after a single application, and lesions healed as fibrosis with 27–40% wall thinning but no aneurysm or tissue disruption.
- Costs: two septal lesions within 1 cm of the aortic cusp caused complete heart block (one transient, one requiring pacing and dopamine for 34 minutes), and bipolar delivery produced central haemorrhage and one microvascular obstruction on MRI, so a thermal contribution cannot be excluded.
- Epicardial lesions spared coronary branches with a preserved lumen; transatrial CO₂/saline-assisted access succeeded in 7/7 animals on full heparin.
- Lesion depth on MRI correlated with necropsy (r=0.88).
- (All: sources/lattice-tip-preclinical-circep-2024, rating: medium)
Dual-energy lattice-tip catheter — first human series
The RF mode of this tip was characterised first: against a conventional 3.5-mm irrigated catheter it doubled ventricular lesion depth in sheep and swine and reached 80% transmurality in bipolar configuration, and it was on that lesion-depth rationale that the catheter entered clinical use. See entities/Sphere-9. (sources/lattice-tip-rf-lesion-circep-2019, rating: medium) (sources/lattice-tip-rf-lesion-jce-2019, rating: medium)
In 18 patients (94% structural heart disease, LVEF 34%, 66% prior failed ablation, 22% electrical storm), high-energy RF was the primary energy and PF consolidated lesions, never near the conduction system and as the only energy epicardially:
- Mapping: ~4,500 points per chamber in ~18 minutes; pace mapping and entrainment frequently impossible because the surface pacing electrodes are small.
- Outcomes: 12 ± 7 RF and 8 ± 9 PF applications per patient; acute non-inducibility 89%; ventricular-arrhythmia-free survival 78% at 3 months.
- Epicardial PF was not transmural by endocardial signal assessment, and coronary spasm occurred in 3 of 4 epicardial patients (tip-to-artery distance 7 ± 3 mm; none at 21 mm), all resolving with intracoronary nitrates.
- No phrenic nerve palsy despite delivery directly on a site with phrenic capture.
- Myocardial capture occurs during PF delivery, so VT termination may be overdrive pace-termination rather than isthmus elimination.
- hsTnT rose from 36 ± 26 to 995 ± 580 ng/L — about a third of the rise seen after AF ablation.
- Large-tip reachability is a real constraint: one inferior basal RV VT needed a 4-mm catheter under the tricuspid leaflet at redo.
- (All: sources/lattice-tip-vt-europace-2024, rating: medium)
The AVAAR registry — largest systematic dataset
126 patients at all 18 European centres using the AFFERA system (VT 99, PVC 23, VF 4; ischaemic 40%, non-ischaemic 46%; LVEF 37%; 64% redo; epicardial access 17%; PFA only 43%, RF only 15%, both 42%):
- Acute success 84% (VT 82%, VF 100%, PVC 91%).
- Free of recurrence 72% at 5.6 ± 3.7 months (VT 70%, VF 100%, PVC 78%); de novo 80% vs redo 68%.
- Major acute complications 6%, minor 14%; major events between day 1 and 30 in a further 6% including 3 deaths — coronary laceration at epicardial access, progressive heart failure at LVEF 15%, and sepsis with tumour lysis.
- Platform-specific hazards: transient ST change in 8 patients (epicardial and RVOT delivery, with documented spasm in five), haemolysis in 3 without renal failure, EMI making mapping impossible in two HeartMate 3 patients, and a shaft insulation rupture causing simultaneous VF and AF during RF.
- Contact and repetition both still matter: recovered areas on remapping lacked the temperature rise that marks an effective application.
- (All: sources/avaar-registry-europace-2025, rating: high)
High-voltage focal PFA
A dedicated focal high-voltage catheter (5 QRS-gated applications of <200 ms, monophasic >10 kV) produced 12.5 ± 3.3 mm deep lesions in swine and, in the first-in-human VCAS trial of 26 patients, 92% acute success, 93% non-inducibility and 81.8% 180-day freedom from VT/VF or ICD shock, with endocardial-only delivery abolishing adjacent epicardial potentials in 9/9. This is single-arm, 6-month evidence only. See concepts/VT-Ablation and sources/pfa-vt-circ-2025. (sources/pfa-af-ehra-2026, rating: very high)
Other ventricular and outflow data summarised in the 2026 statement
- CENTAURI focal contact-force PFA: reasonable PVC outcomes in an initial 20-patient cohort; reproduced in 44 patients, but 3-month VT-free survival only 52% in scar-related VT, with transient conduction-system block in 3 patients (7%), likely from current leakage.
- Focal PFA in 35 patients (about a third after failed RF): acute success 91%, but at ~9 months clinical success 75% for PVC and 45% for VT; two transient conduction blocks and two cerebrovascular events; major complications 6%.
- Sequential, colocalised RF and PF significantly increases ventricular lesion depth and width compared with either alone, with thermal necrosis centrally and PFA damage peripherally — the mechanistic case for hybrid or stacking strategies in thick or fibrotic myocardium.
- CTI ablation is functionally a ventricular-adjacent application and carries the clearest coronary hazard: right coronary spasm, occasionally with malignant ventricular arrhythmias, mitigated but not abolished by IV nitroglycerine.
- (All: sources/pfa-af-ehra-2026)
Papillary muscle and moderator band targets
The preclinical data are the most encouraging part of the field: papillary lesions of ~6 mm with intact chordae and no mitral regurgitation at 21 days, and transmural moderator band ablation including insertion sites — targets where stable contact has always been the obstacle with thermal catheters. Human evidence remains confined to case reports and the PVC subgroup of registries. (sources/lattice-tip-preclinical-circep-2024, rating: medium)
Contradictions / Open Questions
- The depth ceiling is unresolved. Monopolar PFA cannot reliably transmuralise the LV free wall; bipolar PFA can, but only with two catheters, and the separation at which transmurality is lost, and the minimum number of applications, are unknown. (sources/lattice-tip-preclinical-circep-2024, rating: medium)
- Preclinical success has not translated cleanly into durable clinical freedom. PVC outcomes are consistently better than VT outcomes, and the largest registry reports 70% VT freedom at under 6 months — well short of the 81.8% at 6 months in the single-arm VCAS trial and with far more redo patients. Whether these differences are device, substrate or follow-up effects is unknown. (sources/avaar-registry-europace-2025, rating: high)
- Mixed-energy procedures confound attribution. In AVAAR 42% of procedures used both RF and PF, and in the Prague series PF was used to consolidate RF; no study isolates the contribution of PFA to efficacy or to harm. (sources/lattice-tip-vt-europace-2024, rating: medium)
- Coronary spasm is the dominant anatomical risk and its mitigation is prophylactic rather than protocolised. Rates of angiographic spasm reach 75% of epicardial cases in one series, yet nitrates were not given prophylactically and the long-term vascular effect is unknown. (sources/lattice-tip-vt-europace-2024, rating: medium)
- Conduction system injury occurs and is under-characterised. Transient complete heart block after bipolar septal delivery near the aortic cusp, and transient block attributed to current leakage in focal PFA series, define a hazard without an accepted safe distance. (sources/lattice-tip-preclinical-circep-2024, rating: medium)
- Procedural endpoints are unreliable. Myocardial capture during PF delivery can terminate VT by overdrive pacing, epicardial PF leaves endocardial signals unchanged, and non-inducibility has never been validated against durable arrhythmia freedom after PFA. (sources/lattice-tip-vt-europace-2024, rating: medium)
- Safety denominators are small and self-reported. AVAAR is the largest dataset at 126 patients with ~6 months of follow-up; deaths were multifactorial in a fragile population, so procedure-attributable mortality is imprecise. (sources/avaar-registry-europace-2025, rating: high)
Connections
- Companion page to concepts/PFA-Atrial-Arrhythmias — the atrial application and the shared biophysics, devices and dosing
- Related to concepts/VT-Ablation — where ventricular PFA sits among energy options
- Related to concepts/VT-Ablation-Ischemic-Cardiomyopathy — the best-evidenced ventricular substrate
- Related to concepts/VT-Ablation-Nonischemic-Cardiomyopathy — intramural septal substrate and endo-epicardial strategy
- Related to concepts/Epicardial-VT-Ablation — access, coronary spasm and the transmurality trade-off
- Related to concepts/PVC-Mapping-Ablation — outflow tract, papillary muscle and moderator band targets
- Related to concepts/VT-Management — the chronic and acute ventricular arrhythmia pathway
- Related to concepts/Late-Gadolinium-Enhancement — MRI lesion visualisation
- Related to concepts/Electrical-Storm — a frequent indication in these series
- Related to entities/ICD — the comparator therapy in most ventricular PFA cohorts