Focal pulsed field ablation for ventricular tachycardia in ischemic heart disease: a case series

Ablation of ventricular tachycardia is still challenging and has limited efficacy with the traditional thermal energy. Next to its rapidly expanding application in atrial fibrillation (AF) ablation, pulsed field ablation (PFA) may also offer advantages in ablation of ventricular arrhythmias.

We conducted a prospective case series involving 5 male patients (mean age: 68±11.5 years) with ischemic cardiomyopathy (ICM) referred for ablation of monomorphic ventricular tachycardia (MMVT), one patient had VT storm despite therapy with amiodarone and left-sided stellate ganglion blockade (SGB). All five patients exhibited reduced left ventricular ejection fraction (EF) <40%. All ablation procedures were performed under deep sedation. Contact force-sensing catheters, high-density diagnostic catheters, and three-dimensional mapping systems were included to generate detailed electro-anatomical maps (EAM). The ablation was conducted using monopolar biphasic focal pulsed field energy (25 Amperes).

In all patients, the VT substrates were localized within the left ventricle (LV) (Table 1). Fluoroscopy time and radiation dose were minimal, averaging 1.8±0.7 minutes and 39.4±16.6 µGy/m², respectively. The average procedure duration was 224 ± 89.7 minutes, with an ablation time of 920 ± 494 seconds.

In 4 cases, VT was non-inducible at the end of the procedure. In one case (Case 4, characterized by VT storm), we concluded the procedure without testing for VT inducibility due to hemodynamic instability under deep sedation, the necessity for noradrenaline support, and an extended procedural duration (370 minutes). No acute complications related to the procedure were observed. Postprocedural ECG monitoring for 48h showed a stable rhythm without acute recurrence of VT, this was also seen in case 4.

Focal PFA for VT in the LV in the context of ICM demonstrates both efficacy and safety. However, further studies are needed to assess long-term outcomes and to better understand the durability and effectiveness of this approach over extended follow-up periods.Table 1