Bradycardia Dependent QT Prolongation and Ventricular Fibrillation Following Catheter Ablation of the Atrioventricular Junction witb Radiofrequency Energy

Abstract

Recurrent ventricular fibrillation was observed in a 67-year-old woman following catheter ablation of the AV junction using radiofrequency energy. This serious complication has been reported following direct current energy ablation of the AV junction, but not after using radiofrequency energy. This life-threatening arrhythmia seemed pause and bradycardia dependent. It was followed by QTc prolongation of the QRS escape rhythm 1 day after the procedure. Ventricular arrhythmias were suppressed by rapid ventricular pacing.

Catheter Ablation of Accessory Pathways, Atrioventricular Nodal Reentrant Tachycardia, and the Atrioventricular Junction

“…A better understanding of the specific cause of this type of complication and identification of methods to prevent late sudden cardiac death are needed before AVJ ablation becomes more widely performed. The findings from several recent studies [31][32][33] suggest that the early development of malignant ventricular arrhythmias after ablation of the AVJ are pause or bradycardia dependent. Geelen and colleagues 31 reported a 6% incidence of ventricular fibrillation or sudden cardiac death within 1 month after RF ablation of the AVJ when pacing rates were set to 60 bpm compared with a 0% incidence of sudden cardiac death when pacing rates were programmed to 90 bpm for the first 1 to 3 months after the procedure, with subsequent reductions of the pacing rate to 70 bpm.…”

Polymorphic ventricular tachycardia due to change in pacemaker programming

“…The complete AV dissociation in VVI mode combined with the lower pacing rate of 50 bpm created a “functional AV nodal ablation.” Torsades de pointes after AV nodal ablation has been well described 9, 10. An initial pacing rate of 90 bpm following AV nodal ablation, which is reduced over the following months, was found to be protective from polymorphic VT and ventricular fibrillation 11, 12.…”

Practice Standards for ECG Monitoring in Hospital Settings: Executive Summary and Guide for Implementation

“…51 Likewise, torsades de pointes has been reported in patients with chronic atrial fibrillation who have undergone AV junction ablation with the implantation of a pacemaker. 52 Although pacemaker programming to maintain relatively high paced rates is thought to decrease the incidence of this complication, 12 to 24 hours of ECG monitoring is recommended. In addition, patients with significant organic heart disease who undergo ventricular tachycardia ablation warrant postprocedural monitoring for 12 to 24 hours.…”