Randomized, Controlled Trial of the Safety and Effectiveness of a Contact Force–Sensing Irrigated Catheter for Ablation of Paroxysmal Atrial Fibrillation

Abstract

Background-Contact force (CF) is a major determinant of lesion size and transmurality and has the potential to improve efficacy of atrial fibrillation ablation. This study sought to evaluate the safety and effectiveness of a novel irrigated radiofrequency ablation catheter that measures real-time CF in the treatment of patients with paroxysmal atrial fibrillation. Methods and Results-A total of 300 patients with symptomatic, drug-refractory, paroxysmal atrial fibrillation were enrolled in a prospective, multicenter, randomized, controlled trial and randomized to radiofrequency ablation with either a novel CF-sensing catheter or a non-CF catheter (control). The primary effectiveness end point consisted of acute electrical isolation of all pulmonary veins and freedom from recurrent symptomatic atrial arrhythmia off all antiarrhythmic drugs at 12 months. The primary safety end point included device-related serious adverse events. End points were powered to show noninferiority. All pulmonary veins were isolated in both groups. Effectiveness was achieved in 67.8% and 69.4% of subjects in the CF and control arms, respectively (absolute difference, −1.6%; lower limit of 1-sided 95% confidence interval, −10.7%; P=0.0073 for noninferiority). When the CF arm was stratified into optimal CF (≥90% ablations with ≥10 g) and nonoptimal CF groups, effectiveness was achieved in 75.9% versus 58.1%, respectively (P=0.018). The primary safety end point occurred in 1.97% and 1.40% of CF patients and control subjects, respectively (absolute difference, 0.57%; upper limit of 1-sided 95% confidence interval, 3.61%; P=0.0004 for noninferiority). Conclusions-The CF ablation catheter met the primary safety and effectiveness end points. Additionally, optimal CF was associated with improved effectiveness. Clinical Trial Registration-http://www.clinicaltrials.gov. Unique identifier: NCT01278953.(Circulation. 2015;132:907-915.

Lesion Size Index in Maximum Voltage-Guided Cavotricuspid Ablation for Atrial Flutter

“…5,14,15 Another landmark study, TOCCASTAR by Reddy et al, confirmed the importance of using CF-guided strategies in meeting primary safety and effectiveness endpoints in PVI ablation procedures. 16 In results published by Neuzil et al, 10 evidence has been offered that supports the concept that an LSI of greater than 5 predicts reconnection risk in PVI ablation. Although the above studies relate to PVI/PAF ablation, it is reasonable to use these results as a guide at least in qualitative, if not quantitative terms, when considering CTI/AFL ablation.…”

Automated Ablation Annotation Algorithm Reduces Re-conduction of Isolated Pulmonary Vein and Improves Outcome After Catheter Ablation for Atrial Fibrillation

“…CF monitoring is useful in AF ablation in reducing ablation time and additional touch-up ablation and in improving the outcome of initial CA compared with conventional irrigated catheters. 16, 17 We previously reported that high average CF decreased ablation time but did not improve ablation outcome. 18 A recent randomized multi-center controlled trial also indicomplications in either group ( Table 2).…”

Evolution of Force Sensing Technologies

“…and experienced a chronic treatment success rate of 85.5 % versus 72.6 % for the suboptimal CF group (p=0.043). 16 These results highlight the need to standardise operating procedures so as to routinely achieve optimal CF.…”