Functional and electrical responses to ventricular pulsed field ablation: First human characterization of myocardial
Nicoletta Ventrella1, Petr Peichl2, Dan Wichterle2
1Institute for Clinical and Experimental Medicine (IKEM), Prague, Czechia; Charles University, Second Faculty of Medicine, Prague, Czechia.
Heart Rhythm
|July 2, 2026
Summary
Assessing myocardial capture during pulsed electric field (PEF) applications offers a better marker for ventricular tachycardia (VT) ablation success than voltage reduction alone. Loss of capture indicates progressive tissue inexcitability during PFA treatment.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Devices
Background:
- Pulsed field ablation (PFA) is a growing treatment for ventricular tachycardia (VT).
- Reliable intraprocedural markers for lesion formation during PFA are currently lacking.
- Acute voltage attenuation may indicate reversible electroporation, not definitive cell death.
Purpose of the Study:
- To evaluate myocardial capture during sequential pulsed electric field (PEF) applications as an indicator of progressive tissue inexcitability.
- To determine the relationship between voltage reduction and the functional progression of lesions during PFA.
- To explore new intraprocedural markers for PFA in VT ablation.
Main Methods:
- Prospective enrollment of patients undergoing VT ablation with a lattice-tip catheter.
- Delivery of four sequential PEF applications at each site.
- Quantification of myocardial captures via invasive arterial pressure waveform analysis and local voltage measurements before and after applications.
Main Results:
- Myocardial captures progressively decreased with sequential PEF applications (P<0.001), with complete loss of capture in 20% of sites.
- Voltage reduction was immediate (49% after first application, P<0.0001) and plateaued early.
- Complete loss of capture was more common in the right ventricle (P=0.04), and baseline voltage did not predict it.
Conclusions:
- Sequential PEF applications demonstrate a stepwise decrease in myocardial excitability.
- Voltage attenuation shows an early plateau, unlike the progressive loss of capture.
- Monitoring myocardial capture during PEF delivery may serve as a valuable intraprocedural marker for PFA's functional tissue response.
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