title: Cardiac sympathetic innervation via middle cervical and stellate ganglia and antiarrhythmic mechanism of bilateral stellectomy.
abstract: Cardiac sympathetic denervation (CSD) is reported to reduce the burden of ventricular tachyarrhythmias [ventricular tachycardia (VT)/ventricular fibrillation (VF)] in cardiomyopathy patients, but the mechanisms behind this benefit are unknown. In addition, the relative contribution to cardiac innervation of the middle cervical ganglion (MCG), which may contain cardiac neurons and is not removed during this procedure, is unclear. The purpose of this study was to compare sympathetic innervation of the heart via the MCG vs. stellate ganglia, assess effects of bilateral CSD on cardiac function and VT/VF, and determine changes in cardiac sympathetic innervation after CSD to elucidate mechanisms of benefit in 6 normal and 18 infarcted pigs. Electrophysiological and hemodynamic parameters were evaluated at baseline, during bilateral stellate stimulation, and during bilateral MCG stimulation in 6 normal and 12 infarcted animals. Bilateral CSD (removal of bilateral stellates and T2ganglia) was then performed and MCG stimulation repeated. In addition, in 18 infarcted animals VT/VF inducibility was assessed before and after CSD. In infarcted hearts, MCG stimulation resulted in greater chronotropic and inotropic response than stellate ganglion stimulation. Bilateral CSD acutely reduced VT/VF inducibility by 50% in infarcted hearts and prolonged global activation recovery interval. CSD mitigated effects of MCG stimulation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts, without causing hemodynamic compromise. These data demonstrate that the MCG provides significant cardiac sympathetic innervation before CSD and adequate sympathetic innervation after CSD, maintaining hemodynamic stability. Bilateral CSD reduces VT/VF inducibility by improving electrical stability in infarcted hearts in the setting of sympathetic activation.NEW & NOTEWORTHYSympathetic activation in myocardial infarction leads to arrhythmias and worsens heart failure. Bilateral cardiac sympathetic denervation reduces ventricular tachycardia/ventricular fibrillation inducibility and mitigates effects of sympathetic activation on dispersion of repolarization and T-peak to T-end interval in infarcted hearts. Hemodynamic stability is maintained, as innervation via the middle cervical ganglion is not interrupted.
authors.affiliation: UCLA Cardiac Arrhythmia Center, Los Angeles, California; and.|Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: Tadanobu
authors.initials: T
authors.lastname: Irie
authors.affiliation: Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yamakawa
authors.affiliation: UCLA Cardiac Arrhythmia Center, Los Angeles, California; and.|Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: David
authors.initials: D
authors.lastname: Hamon
authors.affiliation: UCLA Cardiac Arrhythmia Center, Los Angeles, California; and.|Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: Keijiro
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: UCLA Cardiac Arrhythmia Center, Los Angeles, California; and.|Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: Kalyanam
authors.initials: K
authors.lastname: Shivkumar
authors.affiliation: UCLA Cardiac Arrhythmia Center, Los Angeles, California; and mvaseghi@mednet.ucla.edu.|Neurocardiology Research Center of Excellence, Los Angeles, California.
authors.forename: Marmar
authors.initials: M
authors.lastname: Vaseghi
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000378:metabolism / Q000503:physiopathology* / Q000601:surgery*; D002304:Cardiac Pacing, Artificial; D004558:Electric Stimulation; D005728:Ganglia, Sympathetic / Q000503:physiopathology* / Q000601:surgery*; D006321:Heart / Q000294:innervation*; D006339:Heart Rate; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology; D009638:Norepinephrine / Q000378:metabolism; D013233:Stellate Ganglion / Q000503:physiopathology* / Q000601:surgery*; D013552:Swine; D013562:Sympathectomy; D013564:Sympathetic Nervous System / Q000378:metabolism / Q000503:physiopathology* / Q000601:surgery*; D017180:Tachycardia, Ventricular / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery; D014693:Ventricular Fibrillation / Q000378:metabolism / Q000503:physiopathology / Q000601:surgery
chemical_list: D009638:Norepinephrine
keywords: autonomic nervous system; cardiac sympathetic denervation; stellectomy; sympathetic nervous system; ventricular arrhythmias