Modulating the Cardiac Autonomic Nervous System: Stay Close to My Heart or Keep Your Distance?

Perioperative cardiac protection research is needed to determine how to prevent and mitigate cardiac injury that can lead to cardiovascular morbidity and mortality. In this month’s issue of Anesthesiology, Howard-Quijano et al.¹  report effects of high thoracic spinal cord stimulation on decreasing sympathetic stimulation of the heart and corresponding ventricular arrhythmias. What is particularly meaningful about this paper is that the authors do experiments on Yorkshire pigs in order to define the biology underlying the favorable cardiac effects of high thoracic spinal cord stimulation. In their manuscript, the authors report findings from an elegant sequence of experiments demonstrating specifically that (1) spinal cord stimulation therapy during cardiac ischemia resulted in fewer ventricular arrhythmias, (2) intrathecal γ-aminobutyric acid type A (GABA_A) and γ-aminobutyric acid type B (GABA_B) receptor blockade eliminated the protective effects of spinal cord stimulation, (3) intrathecal administration of γ-aminobutyric acid (GABA) transaminase...