Cardiac sympathetic denervation in patients with refractory ventricular arrhythmias or electrical storm: intermediate and long-term follow-up

Abstract

Background: Left and bilateral cardiac sympathetic denervation (CSD) have been shown to reduce burden of ventricular arrhythmias acutely in a small number of patients with ventricular tachyarrhythmia (VT) storm. The effects of this procedure beyond the acute setting are unknown.

Objective: The purpose of this study was to evaluate the intermediate and long-term effects of left and bilateral CSD in patients with cardiomyopathy and refractory VT or VT storm.

Methods: Retrospective analysis of medical records for patients who underwent either left or bilateral CSD for VT storm or refractory VT between April 2009 and December 2012 was performed.

Results: Forty-one patients underwent CSD (14 left CSD, 27 bilateral CSD). There was a significant reduction in the burden of implantable cardioverter-defibrillator (ICD) shocks during follow-up compared to the 12 months before the procedure. The number of ICD shocks was reduced from a mean of 19.6 ± 19 preprocedure to 2.3 ± 2.9 postprocedure (P < .001), with 90% of patients experiencing a reduction in ICD shocks. At mean follow-up of 367 ± 251 days postprocedure, survival free of ICD shock was 30% in the left CSD group and 48% in the bilateral CSD group. Shock-free survival was greater in the bilateral group than in the left CSD group (P = .04).

Conclusion: In patients with VT storm, bilateral CSD is more beneficial than left CSD. The beneficial effects of bilateral CSD extend beyond the acute postsympathectomy period, with continued freedom from ICD shocks in 48% of patients and a significant reduction in ICD shocks in 90% of patients.

Keywords: Cardiac denervation; Electrical storm; Sympathectomy; Ventricular arrhythmias.

Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Flow chart of the study cohort. Of the 41 patients, 27 underwent bilateral and 14 underwent left cardiac sympathetic denervation (CSD). LTF = patients lost to long-term follow-up (F/U) with regard to implantable cardioverter-defibrillator (ICD) shock status.

Figure 2

Top: Freedom from implantable cardioverter-defibrillator (ICD) shock. Kaplan-Meier curve for freedom from ICD shock only is shown. For this analysis, death was censored and the patients who were lost to long-term follow were censored at the last follow-up, which was approximately 2 weeks post-procedure. Bottom: Survival free from ICD shock. Kaplan-Meier curves for survival free from ICD shock as well as risk of death and shock for this cohort are shown. Because of the higher incidence of death in this cohort, the survival free from ICD shocks was also driven by the high risk of mortality in this patient population.

Figure 3

Analysis of shock-free survival in the bilateral vs left cardiac sympathetic denervation (CSD) groups. Kaplan-Meier curves for survival free from implantable cardioverter-defibrillator (ICD) shocks are shown for both the bilateral and left CSD subgroups. The 50% median time to shock-free survival was 366 days in the bilateral CSD group and 128 days in the left CSD group (P = .04). The greater survival free of ICD shocks in the bilateral CSD group was partly driven by the higher mortality rate in the left CSD group.

Figure 4

Burden of implantable cardioverter-defibrillator (ICD) shocks pre- and postprocedure. At mean follow-up, the total number of ICD shocks was significantly reduced in both the left and bilateral cardiac sympathetic denervation (CSD) groups after the CSD procedure compared to preprocedure (mean ± SD).