Cryoablation of an atrioventricular nodal reentrant tachycardia in a patient with an implanted deep brain stimulator

Introduction Atrioventricular nodal reentrant tachycardia (AVNRT) is the most frequent paroxysmal supraventricular tachycardia (SVT), with an incidence of 5 cases per 1000 people. Ablation utilizing a radiofrequency current (RFC) energy source is currently the standard treatment. Success rates range between 94% and 100% and complication rates are low, especially with respect to total atrioventricular (AV) block. Implantation of bilateral deep brain stimulators (DBS) is an established treatment for severe, pharmacotherapyrefractive Parkinson disease (PD). Acceptance of this therapy has increased over the past fifteen years, leading to higher implantation rates; therefore, the incidence of patients with DBS has increased. So far, one case report, published by Kanagaratnam et al, demonstrated the performance of a safe and successful RFC ablation in a patient with DBS suffering from AVNRT without device or patient complications. However, the use of an RFC energy source in patients treated with DBS can be dangerous. The electrodes and generators used are generally known to have several interactions, including those with radiofrequency (RF) energy. Nutt et al reported a disastrous outcome of a patient with implanted DBS who was treated by a form of RF energy after an oral surgery, leading to severe brain injury. Furthermore, DBS can cause significant artifacts in electrocardiographic recordings. As a result, catheter ablation of cardiac arrhythmias in patients with PD and implanted stimulators can be challenging, specifically as RFC is the standard energy source used to create ablation lesions. However, catheter ablation of SVT utilizing cryoenergy has become an alternative to RFC ablations.