LAUSR

Introduction Bipolar radiofrequency (Bi-RF) ablation has been utilized to treat atrial and ventricular arrhythmias refractory to standard unipolar RF (Uni-RF) ablation. In order to perform Bi-RF, the configuration of an existing Uni-RF circuit is altered, such that another catheter is designated as the grounding connection for the active RF-delivering ablation catheter, instead of an impedance patch. This arrangement has usually required use of nonmanufactured, custommade cables. Despite its utility in achieving deeper RF lesions compared to standard Uni-RF ablation, particularly in intramural substrate cases, several limitations exist with this construct: (1) connection of the custom-made cable to the grounding port can be tenuous and prone to malfunction; (2) construction and use of the cable requires technical expertise and is not industry standard, which limits availability; (3) active and ground catheters cannot be simultaneously visualized on the electroanatomic mapping (EAM) system, during mapping or ablation; and (4) other surrogates for confirming contact and stability of the catheters, including visualization of local electrograms (EGMs) and contact force, are absent, thus necessitating greater use of fluoroscopy and intracardiac echocardiography (ICE). An investigational device exemption (IDE) trial (ClinicalTrials.gov Identifier: NCT02374476), in which Bi-RF is specifically configured within CARTO (Biosense Webster, Diamond Bar, CA), is underway to assess safety and efficacy, and through which both active and ground