Clinical Utility of Intravenous Nifekalant Injection during Radiofrequency catheter Ablation for Persistent Atrial Fibrillation

Abstract

Background: Radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF) is still challenging even in RFCA-era for AF. The aim of this study was to assess the clinical utility of nifekalant, a pure potassium channel blocker,during RFCA for persistent AF. Methods and Results: We retrospectively enrolled 157 consecutive persistent AF patients undergoing first RFCA procedure with complex fractionated atrial electrogram (CFAE) ablation after pulmonary veins isolation and compared outcomes between patients with (NFK group: N=79) and without (No-NFK group: N=78) additional CFAE ablation using intravenous nifekalant (0.3mg/kg). Primary endpoint was 24-month atrial arrhythmia-free survival post ablation.The prevalence of AF termination was significantly higher in NFK group than No-NFK group (64.6% versus 7.7%, P<0.001). Arrhythmia-free survival, however, was not significantly different between 2 groups (61.5% versus 54.1%, P=0.63).There was no significant difference between 2 groups in the prevalence of recurrent atrial tachycardia (25.0% versus 23.5%, P=0.89). Arrhythmia-free survivalin patients with AF termination during procedure was significantly higher than those without (73.0% versus 41.0%, P=0.002; adjusted hazard ratio 0.48, 95% confidence interval 0.17-0.84, P=0.02) among NFK group,but not among No-NFK group (66.7% versus 53.2%, P=0.53). Conclusions: Intravenous nifekalant injection during additional CFAE ablation did not improve sinus maintenance rate after RFCA procedure for AF, but AF termination by nifekalant injection could be a clinical predictor of better success rates after procedure.

Instability of rotational activation as atrial fibrillation drivers: Assessment by ExTRa Mapping system

“…High %NP was defined as maximum %NP among the three‐time repetitive recordings ≥50% or all %NP ≥30%. In the last 13 patients, nifekalant of 0.3 mg/kg was administered during the substrate homogenization to easily terminate AF, 6,7 because AF was not terminated only by the substrate modification without the substrate homogenization in the first 13 patients. The substrate homogenization was performed to all high %NP areas regardless of AF termination.…”

Comparison of the efficacy and safety of different doses of nifekalant in the instant cardioversion of persistent atrial fibrillation during radiofrequency ablation

“…More recently, nifekalant has been used in the treatment of atrial arrhythmia and cardioversion of AF and atrial flutter 10‐13 . Compared with traditional AADs, such as quinidine, propafenone and amiodarone, nifekalant is a new agent for instant cardioversion of persistent AF, and its prevalence of AF termination after administration during the procedure was approximately 64.6% 14 . Nevertheless, the efficacy and safety of different doses of nifekalant for the rapid cardioversion of persistent AF during RFCA has not been tested in randomized controlled trials (RCTs), and guidelines provide no clear consensus regarding the preferred dose recommended.…”

“…[10][11][12][13] Compared with traditional AADs, such as quinidine, propafenone and amiodarone, nifekalant is a new agent for instant cardioversion of persistent AF, and its prevalence of AF termination after administration during the procedure was approximately 64.6%. 14 Nevertheless, the efficacy and safety of different doses of nifekalant for the rapid cardioversion of persistent AF during RFCA has not been tested in randomized controlled trials (RCTs), and guidelines provide no clear consensus regarding the preferred dose recommended. To address this issue, we conducted the study to evaluate the effectiveness and safety of different doses of intravenous nifekalant with respect to the instant cardioversion of persistent AF during RFCA.…”

Intraprocedural Conversion Efficacy of Intravenous Nifekalant Administration for Persistent Atrial Fibrillation after Pulmonary Vein Isolation

“…[9][10][11] Only sparse data are available regarding the pharmacological conversion of PerAF achieved by intravenous nifekalant administration during the RFCA procedure. 12,13) This study was undertaken to evaluate the efficacy, safety, and predictive effect on the 1-year atrial tachyarrhythmia (ATa)-free survival of intravenous nifekalant administration for PerAF after PVI with second-generation CBA by examining the pharmacological conversion rate.…”