Renal Sympathetic Denervation Provides Ventricular Rate Control But Does Not Prevent Atrial Electrical Remodeling During Atrial Fibrillation

Abstract

A trial fibrillation (AF) is a frequent complication of longstanding hypertension and represents the most common cardiac arrhythmia causing significant morbidity and mortality.1-3 During AF, normal atrioventricular (AV) node conduction leads to a rapid and irregular ventricular rate, resulting in an impairment of left ventricular function and exercise capacity. 4 Rate control can be achieved by drugs modulating the autonomic nervous system, for example, by β-blockers. Genetic inhibition of inhibitory Gα protein in the AV node reduced heart rate (HR) and prevented AF-associated reduction of cardiac function in a porcine model for persistent AF. 5In addition, AF causes atrial electrical remodeling mainly characterized by a pronounced atrial effective refractory period (AERP) shortening perpetuating AF.6 Alterations in the autonomic nervous system may influence AF-induced atrial electrical remodeling and atrial arrhythmogenesis.7-9 Catheterbased renal denervation (RDN) is a new therapeutic approach to reduce sympathetic activity and blood pressure (BP) and to improve obstructive sleep apnea severity and glucose metabolism in resistant hypertension. [10][11][12][13][14][15] However, the effect of RDN on ventricular HR response during AF (rate control) and AF-induced electrical remodeling is unknown.Herein, we report on the effect of catheter-based RDN, shown previously to reduce renal and whole body sympathetic activity, 12-14 on rate control in a patient with permanent AF and resistant hypertension. Subsequently, we investigated the effect of denervation of the afferent and efferent renal sympathetic nerves in a pig model with short-term AF maintained by rapid atrial pacing. Methods Catheter-Based RDN in a Patient With AFThe patient gave written informed consent. Catheter-based RDN was performed as described previously.11-15 Renal angiogram was performed via femoral access to exclude renal artery stenosis. The treatment catheter (Symplicity Catheter System, Ardian/Medtronic USA) Abstract-Renal denervation (RDN) reduces renal efferent and afferent sympathetic activity thereby lowering blood pressure in resistant hypertension. The effect of modulation of the autonomic nervous system by RDN on atrial electrophysiology and ventricular rate control during atrial fibrillation (AF) is unknown. Here we report a reduction of ventricular heart rate in a patient with permanent AF undergoing RDN. Subsequently, we investigated the effect of RDN on AF-induced shortening of atrial effective refractory period, AF inducibility, and ventricular rate control during AF maintained by rapid atrial pacing in 12 pigs undergoing RDN (n=7) or sham procedure (n=5

Effects of Renal Artery Denervation on Ventricular Arrhythmias in a Postinfarct Model

“…Moreover, the peak sinus tachycardia rates in these infarcted hearts increased in the sham RDN group and decreased in the real RDN group. Linz et al 13 demonstrated that RDN reduced the mean ventricular rates during atrial fibrillation by 24% and reduced heart rates during sinus rhythm by a mean of 20 bpm, consistent with the concept highlighted in our model. In the resistant hypertension setting, RDN reduced mean sinus rates more modestly by 2 to 3 bpm 14 and by 4 bpm 15 in 2 different studies.…”

Renal Denervation for Ventricular Arrhythmia in Patients with Implantable Cardioverter Defibrillators

“…In prior animal researches, we had already found that RDN could suppress norepinephrine spillover. 24,32) However, many researchers used the term "renal denervation" instead of "intra-renal artery ablation." Scientifically, as long as denervation is not examined in the individuals, the intravascular procedure cannot be called the "denervation."…”

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

“…24 In contrast, renal denervation was reported to reduce the duration of rapid pacing-induced atrial fibrillation in the pig, by which the AERP and P-wave duration were hardly affected. 31 Moreover, the combination of pulmonary vein isolation therapy and renal denervation has been clinically reported to reduce the recurrence of atrial fibrillation more than pulmonary vein isolation alone. 13 However, in this study, renal denervation hardly affected the AERP, indicating that the treatment might not be so effective to suppress and/or prevent atrial fibrillation compared with amiodarone.…”

“…Both kidneys were approached through bilateral retroperitoneal flank incisions, and were surgically denervated by removing the visible nerves in the area of the renal hilus, followed by stripping connective tissue around the renal arteries. 31 After the surgical denervation, the incision sites were restored, and proper care was taken of the animals.…”