Carto xp

The ThermoCool SmartTouch catheter (Biosense Webster, Inc., Diamond Bar, California) is a 7.5 Fr CF sensing catheter and has a 3.5 mm tip electrode with 6 small holes (0.4 mm diameter) around the circumference for saline irrigation. The catheter tip electrode is mounted on a precision spring, which permits micro-deflection, which is measured by three magnetic sensors located proximal to the spring. The system calculates the associated magnitude and angle of CF based on the micro-deflection, which is displayed both continuously and as the average value (over 1 s) on an electroanatomical mapping system (CARTO XP, Biosense Webster, Inc.) [4] (link).
The ThermoCool SF Catheter (Biosense Webster, Inc) is a non-CF sensing, open irrigation catheter with an 8 Fr tip electrode, 3.5 mm in length with 56 very small holes (diameter 0.0035″) positioned around the entire electrode. It contains an embedded thermocouple for monitoring electrode temperature during RF ablation.

Ablation was guided by 3-dimensional electroanatomical mapping using CARTO (CARTO XP or CARTO-3; Biosense Webster Inc., Diamond Bar, CA, USA) or EnSite (EnSite NavX Classic or EnSite Velocity; Abbott Laboratories, North Chicago, IL, USA) mapping system. A duo-decapolar Lasso circular mapping catheter was used to guide and map the PV. Ablation was performed using open irrigation catheters (Celsius or Navistar Thermocool SF; Biosense Webster Inc., Cool Flex; Abbott Laboratories). All patients underwent circumferential PV isolation. Exit and entrance blocks were confirmed after PV isolation. For patients with persistent AF, additional ablation was performed at the roof line, posterior inferior line, anterior line, mitral isthmus line, cavotricuspid line, or regions of complex fractionated electrograms, at the operator's discretion.

In the RF ablation group, pulmonary vein isolation was achieved using an irrigated catheter (6-hole irrigated THERMOCOOL^® catheter family with or without contact force [CF] sensing or porous-tip THERMOCOOL^® SF catheter, Biosense Webster, Inc., Irvine, CA, USA) in conjunction with a 3-dimensional electroanatomic mapping system (CARTO^® 3, CARTO^® XP, or CARTO^® RMT systems, Biosense Webster, Inc., Irvine, CA, USA). Procedures were performed as per standard of care and processes required by the participating sites. In the AAD group, medication was managed according to current guidelines^{5 ,6} (link) at the investigators’ discretion. At the time of trial enrolment, if patients randomized to the AAD group had already been switched from a failed medication to a new AAD, they continued with this agent after enrolment; otherwise, a newly prescribed AAD regimen was initiated. Patients randomized to AAD could cross over to the RF ablation group after optimization of AAD and management of noncompliance. For management of arrhythmia recurrence, investigators’ usual clinical practice was followed as closely as possible. Changes in AAD treatment during the trial were permitted in accordance with current AF management guidelines.^{5 ,6} (link) Follow-up procedures are described in detail in Supplementary material online, Appendix.