Cardiac sympathetic denervation in the prevention of genetically mediated life-threatening ventricular arrhythmias

Abstract

Proper management of patients affected by genetic disorders causing life-threatening arrhythmias is important for several reasons, including even societal ones, given the predominantly young age of those affected. Incorrect management often has dire consequences, ranging from unnecessary psychologic damage for the patients whose life becomes too limited by the fear of sudden death to equally avoidable tragedies when the entire armamentarium of effective therapies is not fully utilized. In this review, we focus primarily on long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT) and deal specifically with the clinical impact of the most commonly used cardiac sympathetic denervation (CSD), namely left cardiac sympathetic denervation (LCSD). The two of us have used LCSD in the management of our patients with either LQTS or CPVT for a very long time and have been involved in ∼500 such interventions. It is on the basis of this personal and direct experience that we wish to share our views with clinical cardiologists and electrophysiologists, adult and paediatric, and with genetic cardiologists. We will begin by reviewing the history and rationale underlying sympathetic denervation therapy and will continue with a disease-specific intensification of therapy, and then with a discussion on how the impressive efficacy of LCSD should translate into guideline-directed therapy in both current and future guidelines, in order to upgrade the quality of care in the era of precision medicine.

Keywords: Cardiac sympathetic denervation; Catecholaminergic polymorphic ventricular tachycardia; Genetic disorders; Left cardiac sympathetic denervation; Long QT syndrome; Sudden cardiac death.

Graphical Abstract

How recommendations for cardiac sympathetic denervation in patients with either long QT syndrome or catecholaminergic polymorphic ventricular tachycardia would look like if they were written by the two of us. LQTS, long QT syndrome; CPVT, catecholaminergic polymorphic ventricular tachycardia.

Figure 1

Groups of patients for whom left cardiac sympathetic denervation could be indicated. The level of risk decreases progressively from Group 1 to Group 4B (from red to light green). The rate of success varies within these groups according to Dusi et al. and in some cases an implantable cardioverter defibrillator may become necessary. For Groups 4A and 4B, left cardiac sympathetic denervation is recommended as the primary prevention because these patients are still asymptomatic, but their electrocardiographic pattern suggests a higher or lower risk. See text for details. βB, beta-blocker; CALM, calmodulin; JLN, Jervell and Lange-Nielsen; LCSD, left cardiac sympathetic denervation; LQTS, long QT syndrome.

Figure 2

An anatomical drawing of the left cardiac sympathetic chain after exposure through the pleura that is resected during video-assisted thoracic left cardiac sympathetic denervation. The stellate ganglion is located under the superior edge of the incision. The dashed line indicates the resection of the lower half of the left stellate ganglion occurring just above the major lower branches, to minimize the risk of the Horner syndrome. The lower section should take place below T4. Prior to performing the section, lidocaine should be applied on the sympathetic chain. (From Collura et al. with permission.)

Figure 3

On treatment Kaplan–Meier curves of cumulative survival to any cardiac event (A) and to a sudden death/aborted cardiac arrest/implantable cardioverter defibrillator shocks (B) after left cardiac sympathetic denervation in LQTS patients with previous syncope/implantable cardioverter defibrillator shocks according to post-left cardiac sympathetic denervation QTc <500 or ≥500 ms. The patients who at 6 months post-left cardiac sympathetic denervation have a QTc <500 ms are at a significantly lower risk for all cardiac events and especially for sudden death/aborted cardiac arrest/implantable cardioverter defibrillator shocks. (Modified from Dusi et al. with permission.) SD, sudden death; ACA, aborted cardiac arrest; ICD, implantable cardioverter defibrillator; LCSD, left cardiac sympathetic denervation.