Renal sympathetic denervation in patients with implantable cardioverter-defibrillator and electrical storm

Background

Implantable cardioverter-defibrillators (ICDs) are usually indicated for patients with malignant arrhythmias considered as high risk. Sympathetic hyperactivity plays a critical role in the development, maintenance, and worsening of ventricular arrhythmias. New treatment options in this population represent a clinical necessity. This study's objective was to report the outcomes of patients with ICDs and electrical storm submitted to renal sympathetic denervation for arrhythmia control.

Methods

Eight patients with ICDs admitted for electrical storm refractory to optimal medical therapy underwent renal sympathetic denervation. Underlying diseases included Chagas disease (n = 6), non-ischemic dilated cardiomyopathy (n = 1), and ischemic cardiomyopathy (n = 1). Information on the number of episodes of ventricular tachycardia/ventricular fibrillation and antitachycardia therapies in the week before the procedure and 30 days after treatment were obtained through interrogation of the ICDs.

Results

The median numbers of episodes of ventricular tachycardia/ventricular fibrillation, antitachycardia pacing, and shocks in the week before renal sympathetic denervation were 29 (9 to 106), 23 (2 to 94), and 7.5 (1 to 88), and significantly reduced to 0 (0 to 12), 0 (0 to 30), and 0 (0 to 1), respectively, 1 month after the procedure (p = 0.002; p = 0.01; p = 0.003, respectively). No patients died during follow-up. There were no major complications related to the procedure.

Conclusions

In patients with ICDs and electrical storm refractory to optimal medical treatment, renal sympathetic denervation significantly reduced arrhythmia load and, consequently, antitachycardia pacing and shocks. Randomized clinical trials in the context of renal sympathetic denervation to control refractory cardiac arrhythmias are needed to further support these findings.