Late left ventricular summit premature ventricular contractions elimination with new TactiFlex irrigation technology

BACKGROUND: Premature ventricular contractions (PVCs) originating from the left ventricular summit (LVS) could be challenging to ablate due to anatomical reasons. AIM: To study the role of new irrigation technologies, like the TactiFlex catheter, could facilitate deeper radiofrequency (RF) penetration and thus increase success in the ablative treatment of this PVC subset. METHODS: Three PVCs focus (left bundle branch block morphology, inferior axis on the frontal plane, early R/S transition in V1-V2) were accurately mapped with Ensite X omnipolar technology. RESULTS: RF was delivered at mitroaortic continuity by TactiFlex catheter (4-9 lesions, max 35 W, 43 °C, 13 mL/minute, max 60 seconds, mean impedance drop 11.9 ± 1.7 ohms) with acute PVCs suppression but early recurrence in all cases. In one case, an anatomical approach in the posteroseptal right ventricular outflow tract was performed without acute success. After 6-10 hours, no PVCs/ventricular arrhythmias have been detected, and no arrhythmia recurrences in all 3 cases at a 180-day follow-up visit. These data were compared with a cohort of 10 patients with LVS PVCs with immediate disappearance treated with the same technology; the only difference, although not statistically significant, was in the greater drop in impedance (13.5 ± 2.1 ohms). CONCLUSION: Late PVCs elimination could be due to the porous flexible distal tip design of the TactiFlex catheter that allows deeper RF penetration in the myocardium due to a greater adhesion of the saline irrigation system to tissue. It is reasonable to assume that this new technology makes lesions more transmural, determining a delayed lesion maturation, thus not limited to the duration of energy delivery.