Entirely anatomical high-power ablation for refractory left ventricular summit arrhythmias

Introduction Ventricular arrhythmias (VA) originating from the left ventricular summit (LVS) can be difficult to eliminate, and outcomes after standard ablation are frequently suboptimal. This study evaluated the safety and effectiveness of entirely anatomical high-power radiofrequency (RF) re-ablation in patients after previously failed LVS VA procedures. Purpose To determine whether an anatomically guided ablation delivered at high-power values can achieve safe and effective elimination of LVS VA in patients after prior unsuccessful ablation. Methods Consecutive patients undergoing re-ablation for symptomatic, drug-refractory LVS arrhythmias were included. Anatomical ablation was performed with high-power values (50-70W) from adjacent structures [coronary cusps, subaortic left ventricular outflow tract (LVOT)]. Concordant dispersive patch position was used in all patients included in the study. Acute success was defined as complete VA elimination during ≥15 minutes of observation, including salbutamol provocation. Results Fifteen patients (12 males; mean age 56 ± 14 years) underwent anatomical re-ablation after 2±2 prior ineffective procedures (range 1–9). The subaortic LVOT was the initial target in 8 patients (53%), while 4 patients (27%) were treated from the coronary cusps. In 3 patients (20%), unipolar applications were delivered both within aortic cusps and the subaortic LVOT. The mean RF time of the unipolar ablation was 291±197 s with a mean power of 53±9 W. Acute PVC elimination was achieved in 7 patients (47%). No complications occurred. During 14±9 months of follow up there was no recurrence of clinically relevant VA in all 7 patients after successful anatomical re-ablation. In those remaining 8 patients (53%) without acute success of entirely anatomical approach, advanced ablation strategies (bipolar ablation, pulsed field ablation, or alcohol ablation) following the anatomical approach were needed. Conclusions Entirely anatomical high-power RF re-ablation of LVS VA is safe and can be effective in significant number of patients after initially failed ablations. Acute effective elimination of clinical LVS VA with presented technique corresponds with good long term outcome. Advanced ablation strategies are still needed in approximately every second patient undergoing repeat LVS VA ablation.