Multielectrode catheter-induced ectopy mapping: a novel technique for ablation of infrequent premature ventricular contractions.

Background: Ablation of infrequent premature ventricular complexes (PVC) is challenging.

Objectives: A novel mapping strategy for patients with infrequent PVCs, called multielectrode catheter-induced ectopy mapping (MECIE mapping) is described, aiming at performing a hybrid activation/template matching map by taking advantage of multielectrode catheter-induced arrhythmogenicity.

Methods: Patients referred to 3 tertiary centers for PVC ablation were prospectively enrolled if they had infrequent PVCs (less than 1 PVC per minute) at onset of procedure, preventing the realization of an accurate activation map. A detailed MECIE map was created using the arrhythmogenic property of multielectrode catheters, corresponding to a local activation time (LAT) map generated by annotating LAT from mechanical PVCs. Selecting mechanical PVCs with ≥99% concordance with the clinical PVC spotted the site of origin at which ablation was delivered. The primary endpoint was long-term success, defined as an >80% reduction in PVC burden during follow-up.

Results: A total of 29 patients were included, with 25 (interquartile range [IQR] 7-30) PVCs in the initial 30 minutes of procedure. During MECIE mapping, 67 (IQR 1-332) points with ≥99% concordance were acquired. The best LAT was 34.0 ± 9.5 ms before QRS onset. Pace mapping was 97.4 ± 3.1% compared with the clinical PVC. Ablation was locally performed. After 13.2 ± 5.1 months of follow-up, 27 patients (93.1 %) had 80% reduction in PVC burden, and only 2 patients had symptomatic recurrences.

Conclusion: A detailed MECIE map taking advantage of multielectrode catheter arrhythmogenicity may be generated to spot the origin of PVCs, a strategy resulting in a good procedural success rate.