Can spinal cord stimulation reduce ventricular arrhythmias?

Sudden cardiac death is the largest cause of natural death in Western countries. Most sudden cardiac deaths are caused by malignant ventricular arrhythmias. The occurrence of sudden cardiac death and ventricular tachyarrhythmia (VT)/ventricular fibrillation (VF) episodes and is associated with an imbalance between sympathetic and parasympathetic tone. Spinal cord stimulation (SCS) could restore autonomic balance by inhibiting sympathetic stimulation of the heart. Accumulating evidence demonstrates that SCS is a safe antianginal treatment that does not hide myocardial infarction symptoms. Recently, it was shown that SCS modifies the capacity of intrinsic cardiac neurons to generate activity. SCS also acts to suppress the excitatory effects that local myocardial ischemia exerts on such neurons. Issa et al showed in dogs that the occurrence of VT/VF is reduced from 59% to 23% when SCS was applied during transient myocardial ischemia. SCS also appeared to have an antiarrhythmic effect on spontaneous nonsustained VT and sustained VT during ischemia reperfusion in association with a reduction of repolarization alterations in a porcine ischemia-reperfusion model. In addition, long-term SCS significantly decreased ventricular arrhythmias and improved cardiac contractile function in canine heart failure. These findings raise the question whether SCS may also stabilize electrophysiological properties and thereby the incidence of VT/VF in humans. We report preliminary findings of 2 patients with a high VT/VF burden, which were subjected to SCS On and Off for 2 months.