Background: Pulsed field ablation (PFA) to isolate PVs was recently reported with an expandable over-the-wire basket/flower catheter. PFA’s advantages over thermal ablation include myocardial specificity, an ultra-rapid workflow and no thermal extremes in the LA environment. Beyond PVI, creation of linear lesions requires focal PFA catheters.
Objective: To assess the feasibility of a novel focal PFA catheter to create linear atrial lesions.
Methods: Under general anesthesia, 3D electroanatomic LA maps were created (CARTO, Biosense Webster Inc). Then, a 12 Fr expandable focal catheter (Faraflex, Farapulse Inc) was maneuvered with a deflectable sheath to create linear lesions in 3 swine: beginning at 12 o’clock on the mitral annulus and traversing across the roof posteriorly to the inferior common PV. Biphasic PFA applications at each site were overlapped with adjacent lesions (guided by the CARTO system) to achieve lesion overlap and contiguity. Post ablation voltage maps were created with a high-density catheter, and the width of line (bipolar voltage<0.5mV) was measured in 5 discrete locations along the line.
Results: Continuous linear lesions spanning the intended path were observed in all 3 (100%) swine. The number of applications required were 13, 11, and 16, with total application times of 28sec, 23sec, and 34sec, respectively. The average linear lesion widths were 9.2mm, 7.8mm, 7.8mm, 16.2mm, 13.1mm, respectively. Necropsy revealed identifiable lesions extending from the mitral annulus to the inferior common PV.
Conclusion: This novel focal PFA catheter can create linear left atrial lesions in swine, thereby allowing the possibility for PFA atrial ablation beyond PVI.