Secret signal delayed mapping in patients with premature ventricular contractions.

Introduction: Mapping and radiofrequency ablation (RFA) of premature ventricular contractions (PVC) that show diurnal changes during the day, and which are rare during 3-D mapping has become very difficult. The most delayed signal mapping in the right ventricular outflow tract (RVOT) with RV apical pacing might be useful in these situations and we called this method Secret Signal Delayed Mapping (SSDM).

Aim: To compare the classical RFA and SSDM in patients with PVC.

Material and methods: A total of 60 patients with > 10% PVCs detected in 24-hour rhythm Holter recordings and admitted to the laboratory for RFA, 30 of whom underwent classical ablation according to the local activation time (LAT) and 30 of whom were included in the SSDM group, were included in our study. In patients who did not have enough PVCs during 3-D mapping, a catheter was placed in the right ventricle, and delayed signals after the ventricular electrogram (EGM) were collected by fixed pacing and such patients were included in the SSDM group.

Results: In all patients, PVC originated from the RVOT. The mean follow-up time of the patients was 10.2 ±1.6 months. Recurrence was detected in 11 (36.6%) patients in the LAT group and 4 (13.3%) patients in the SSDM group. Signal earlyness in LAT mapping was significantly higher in the LAT group (p < 0.001). In the SSDM group, an average of 128 ±24 delayed signals were collected, the mean delayed signal time was 77.6 ±17.7 ms. In the SSDM group, the average distance between the earliest signal on the LAT and the most delayed signal on the SSDM was 4.8 ±1.2 mm.

Conclusions: In the treatment of PVCs with RFA, the SSDM method can be used in addition to classical ablation.