Main Findings
We evaluated the VT recurrence in patients in whom VT non-inducibility could not be achieved at the end of the RF ablation and the factors attributed to the VT recurrence in ICM and NICM patients.
The main findings of our study were:
1. During the median follow-up period of 1.4 years (IQR, 0.3-2.0), 66% of the patients in whom VT non-inducibility could not be achieved at the end of RF ablation had no recurrence.
2. Patients whose LVEF was more than or equal to 35%, or in whom all clinical VT isthmuses could successfully be identify and ablated were independent predictors of fewer VT recurrences in the multivariate analysis.
3. Even in patients with VT recurrences, VT ablation could significantly reduce the VT burden.
Endpoint of the VT ablationIt is known that VT non-inducibility at the end of the VT ablation is less likely to be associate with a VT recurrence6,7and achieving the combined endpoint of the abolition of the abnormal electrograms and VT non-inducibility further reduces the VT recurrence.8,9 In the present study, 20 patients in whom VT non-inducibility was achieved had a small VT recurrence rate of 15%. However, we need to consider the risk of overtreatment at the same time; the enlargement of a scar area by RF ablation may lead to a more depressed cardiac function. There is not enough detailed reporting on the subsequent events in patients with residual VT inducibility at the end of the procedure. In our study, patients with an LVEF≄35% or successful identification and ablation of all clinical VT isthmuses were independent predictors of VT non-recurrence in patients in whom VT non-inducibility was not achieved. This may indicate that we should try to identify the isthmus of the clinical VT as much as possible, and that in this group of patients, inducible residual non-clinical VT is acceptable.