Left cardiac sympathetic denervation in the therapy of congenital long QT syndrome. A worldwide report.

Abstract

BACKGROUND Long QT syndrome (LQTS) is a congenital disorder accompanied by a high incidence of sudden cardiac death. beta-Adrenergic blockade is the therapy of choice, and it is successful in 75-80% of patients. For those in whom cardiac events (syncope or cardiac arrest) are not prevented by beta-blockade, experimental studies suggest that left cardiac sympathetic denervation (LCSD) may be useful. METHODS AND RESULTS We identified 85 LQTS patients worldwide who underwent LCSD, and we provide here the first large-scale evaluation of its efficacy. The time interval between the first cardiac event and LCSD and the follow-up period after LCSD were similar (5.6 +/- 6.1 versus 5.9 +/- 5.7 years). The mean age of the patients at surgery was 20 +/- 13 years. LCSD was followed by highly significant (p less than 0.0001) decreases in the number of patients with cardiac events (from 99% to 45%), in the number of cardiac events per patient (from 22 +/- 32 to 1 +/- 3), and in the number of patients with five or more cardiac events (from 71% to 10%). There were seven sudden deaths (8%), and the 5-year survival rate was 94%. The marked reduction in the incidence of tachyarrhythmic syncope suggests that LCSD has also reduced the risk for sudden death in this high-risk population. CONCLUSIONS The present findings demonstrate that for LQTS patients who continue with syncope or cardiac arrest despite the use of beta-blockers, LCSD is a very effective therapy.

Left Cardiac Sympathetic Denervation in the Management of High-Risk Patients Affected by the Long-QT Syndrome

“…10 Importantly for the assessment of the present results, the population under study was at particularly high risk for arrhythmic death, as indicated by the number of symptomatic patients (99%), the high percentage (75%) of those with cardiac events despite ␤-blockers, and the extreme average prolongation of the QT interval (QTc, 543Ϯ65 ms). The last value, which reflects a major arrhythmogenic substrate, 17 should be compared with the mean QTc (QTc, 510Ϯ60 ms) of the largest population in which the effect of ␤-blockers was analyzed.…”

“…Worldwide experience with LCSD in 85 LQTS patients was reported in 1991. 10 Now, 13 years later, we thought it appropriate to review the existing data on 162 patients who underwent left sympathectomy because this large population and the long follow-up permit a more definitive assessment of the role of LCSD in the management of high-risk LQTS patients.…”

The Role of the Autonomic Nervous System in Sudden Cardiac Death

“…Furthermore, epinephrine may induce torsade, whereas left sympathectomy and β-blockers are antiarrhythmic in LQT1. 56,57 These studies suggest that sympathetic activation is arrhythmogenic if I Ks is abnormal or down-regulated. Furthermore, over-expression of NGF in adult transgenic mice results in further decrease in density of at least 2 other potassium currents, I to and I Kur .…”

Baroreflex Sensitivity Predicts the Induction of Ventricular Arrhythmias by Cesium Chloride in Rabbits

“…[2][3][4] Torsade de pointes associated with the long QT syndrome is often elicited by sudden increases in sympathetic activity 8 and can be suppressed by -adrenergic blocking agents 9 or by ablation of the left stellate ganglion. 10 Isoproterenol infusion prolongs the MAP duration and induces EADs in patients with long QT syndrome. 11 In addition, left stellate stimulation increases the amplitude of EADs induced by Cs and increases the occurrence of ventricular tachycardia (VT) in dogs.…”