Impact of computed tomography image and contact force technology on catheter ablation for atrial fibrillation

Abstract

Aim: To investigate the impact of using computed tomography (CT) and contact force (CF) technology on recurrence of atrial tachyarrhythmia after atrial fibrillation (AF) ablation.

Methods: This non-randomized study included 2 groups of patients. All patients had symptomatic recurrent paroxysmal or persistent AF and were treated with at least 1 anti arrhythmic medication or intolerant to medication. The first group included 33 patients who underwent circumferential pulmonary veins isolation (PVI) for AF during 2012 and 2013 guided by CT image integration (Cartomerge, Biosense Webster, Diamond Bar, CA, United States) of left atrium and pulmonary veins into an electroanatomic mapping (EAM) system (CT group) using standard irrigated radiofrequency catheter (ThermoCool, Carto, Biosense Webster, Diamond Bar, CA, United States) or irrigated catheter with integrated CF sensor (Smart Touch, Carto, Biosense Webster, Diamond Bar, CA, United States). The second group included immediately preceding 32 patients who had circumferential PVI by standard irrigated catheter (ThermoCool) using only EAM (Carto) system (EAM group). Linear lesions were performed according to the discretion of operator.

Results: Sex, age, and persistent AF were not different between groups. PVI was achieved in all patients in both groups. Linear ablations including cavo-tricuspid isthmus and or roof line ablation were not different between groups. Free of atrial tachyarrhythmia during follow-up of 24 mo was significantly higher among CT group compared to EAM group (81% vs 55%; respectively; P = 0.027). When 11 patients from CT group who had ablation using Smart Touch catheter were excluded, the difference between CT group and EAM became non significant (73% vs 55%; respectively; P = 0.16). Sub analysis of CT group showed that patients who had ablation using Smart Touch catheter tend to be more free of atrial tachyarrhythmia compared to patients who had ablation using standard irrigated catheter during follow-up (100% vs 73%; respectively; P = 0.07). Major complications (pericardial effusion, cerebrovascular accident/transient ischemic attack, vascular access injury requiring intervention) did not occurred in both groups.

Conclusion: These preliminary results suggest that CT image integration and CF technology may reduce the recurrence of atrial tachyarrhythmia after catheter ablation for AF.

Keywords: Atrial fibrillation; Catheter ablation; Contact force; Image integration.

Figures

Figure 1

Carto screenshot during pulmonary veins isolation. A: Anterior-posterior view showing CT image of left atrium integrated into the electroanatomic map (CT group). The ablation in this case was performed using the Smart Touch catheter. The tip of the Smart Touch catheter is shown with 3D vector; B: Posterior-anterior view showing electroanatomic mapping (EAM group) of left atrium with ablation points around pulmonary veins. EAM: Electroanatomic mapping; CT: Computed tomography; 3D: Three dimension.

Figure 2

Flowchart reporting the different patient groups and the results. ST: Smart touch; AT: Atrial tachyarrhythmia; EAM: Electroanatomic mapping; CT: Computed tomography.

Figure 3

Free of atrial tachyarrhythmia during 24 mo. A: Among CT group vs among electroanatomic group; B: Free of atrial tachyarrhythmia among CT group (excluding Smart Touch) vs among electroanatomic group; C: Free of atrial tachyarrhythmia among CT group with or without ST. ST: Smart touch; EAM: Electroanatomic mapping; CT: Computed tomography.

Figure 4

Kaplan-Meier estimate of recurrence atrial tachyarrhythmia during 3-24 mo after ablation for atrial fibrillation. Free of atrial tachyarrhythmia was significantly higher among CT group compared to electroanatomic mapping group. AT: Atrial tachyarrhythmia; EAM: Electroanatomic mapping; CT: Computed tomography.