PULSED-ELECTRIC FIELD ABLATION OF CAVOTRICUSPID ISTHMUS: A RANDOMIZED COMPARISON OF FLOWER AND BASKET CONFIGURATION OF PENTASPLINE CATHETER

Background
Cavo-tricuspid isthmus (CTI) ablation is commonly performed as a concomitant procedure in patients undergoing catheter ablation of atrial fibrillation (AF). However, the acute efficacy of the CTI ablation using pentaspline Farawave catheter and pulsed-electric field (PEF) energy has not been systematically evaluated.

Aims
We compared acute efficacy and the extent of hemolysis between the two available configurations (basket or flower) of the pentaspline catheter used for CTI ablation.

Methods
A total of 36 patients (age 64±10 years, males 60%) undergoing PEF ablation of CTI concomitantly to AF ablation were randomly assigned to receive ablation using either the basket configuration (n=20) or the flower configuration (n=16) of the pentaspline catheter. The CTI ablation was guided by intracardiac echocardiography. The two groups were compared based on the number of PEF applications required to achieve block and complete CTI ablation and free hemoglobin (fHb) plasma levels.

Results
CTI length and morphology were comparable in both study groups. CTI block was achieved in all patients. The use of flower compared to the basket configuration of the ablation catheter resulted in a significantly lower number of PEF applications needed to achieve the CTI bidirectional block and to ablate the CTI anatomically. Ablation with the flower vs. basket configuration also resulted in significantly less hemolysis due to a lower total number of PEF applications and 2.3 times lower hemolysis per single application (Table).

Conclusion
PEF ablation of CTI using flower vs. basket configuration of pentaspline catheter appeared more effective in achieving the acute CTI block and safer in terms of hemolysis. This can be explained by the larger footprint and better tissue contact of all electrodes, which minimizes the PEF energy leakage into the blood pool.