Impacts of Surgically Performed Renal Denervation on the Cardiovascular and Electrophysiological Variables in the Chronic Atrioventricular Block Dogs　– Comparison With Those of Amiodarone Treatment –

BACKGROUND: In order to begin to precisely clarify the impact of renal denervation on the blood pressure, atrial fibrillation and ventricular tachyarrhythmias, in addition to proarrhythmic potential, its cardiovascular effects were assessed by using the chronic complete atrioventricular block dogs. METHODS AND RESULTS: Cardiohemodynamic and electrophysiological effects, together with neurohumoral factors and/or electrolytes, were assessed before and 4 weeks after either renal denervation (n=5) or amiodarone treatment (n=6). Amiodarone hydrochloride was given orally to the animals every day in a dose of 200 mg/day for the first 7 days followed by 100 mg/day for the following 21 days. The renal denervation decreased the systolic pressure, idioventricular rate, prolonged ventricular effective refractory period, and slightly suppressed the adrenergic tone and the renin-angiotensin-aldosterone system, but hardly affected the atrial effective refractory period and terminal repolarization period. Amiodarone prolonged the atrial effective refractory period, whereas no significant change was detected in the other variables. CONCLUSIONS: Surgically performed renal denervation may possess the anti-ventricular tachyarrhythmic rather than anti-atrial fibrillatory potentials, and it also modestly decreased the blood pressure. Thus, currently obtained information may be used as guidance for better understanding the utility and limitation of renal denervation against various types of cardiovascular diseases. (Circ J 2016; 80: 1556-1563).