Distal-to-Proximal Conduction System Ablation as a Bailout Strategy in Refractory Multi-Exit Purkinje-Related Premature Ventricular Contractions and Ventricular Fibrillation.

BACKGROUND

Ablation of premature ventricular contractions (PVCs) originating from the Purkinje network-particularly those with multiple exit sites and morphologies-poses a significant clinical challenge. In refractory cases where conventional ablation fails, proximal conduction system ablation may represent a viable alternative strategy.

OBJECTIVE

to evaluate the safety and efficacy of proximal conduction system ablation in patients with refractory multi-exit Purkinje PVCs with diverse morphologies.

METHODS

This retrospective cohort included consecutive patients with drug-refractory, symptomatic Purkinje PVCs who underwent proximal conduction system ablation. Multiple exit sites and morphologies were observed during mapping and ablation, indicating complex activation within the Purkinje network.

RESULTS

Among the 22 patients included, 14 (63.6%) had PVC-triggered ventricular fibrillation. Acute elimination of the PVC by distal-to-proximal conduction system ablation achieved in 21 patients (95.5%), while one procedure (4.5%) was discontinued at the patient's request due to the anticipated risk of conduction system injury. The initial site of earliest activation arose from the posterior fascicle in 63.6% (n=14), the septal fascicle in 22.7% (n=5) and the anterior fascicle in 13.6% (n=3). During ablation, all patients demonstrated a shift in the site of earliest activation. Conduction disturbances occurred in 5 patients (22.7%). During a median follow-up of 32.3 months (IQR 17.5-54.5), one patient (4.5%) experienced PVC recurrence requiring repeat ablation; however, no patient experienced recurrent ventricular fibrillation.

CONCLUSION

Distal-to-proximal conduction system ablation can be an effective bailout strategy for patients with refractory multi-exit fascicular/Purkinje-related PVCs and recurrent VF. Larger prospective studies are needed to confirm its long-term safety and efficacy.