Targeting of cardiac autonomic plexus for modulation of intracardiac neural tone.
OBJECTIVE
Ventricular rate control is considered as an initial choice of therapy in many patients with atrial fibrillation (AF). We could previously show that electrostimulation of the right inferior ganglionated plexus (RIGP), which supplies the AV node, instantly decreases ventricular rate during AF. This study describes the development of a technique to reliably implant a chronic lead inside the RIGP.


RESULTS
In nine mongrel dogs with AF, the RIGP was identified by neuromapping with probatory high-frequency stimulation (20 Hz) over steerable electrode catheters until a significant ventricular rate slowing was achieved. Then an active fixation, permanent pacemaker lead was fixed closed to the mapping catheter left in place as anatomical marker. Initially (n = 4) available guiding catheters and steerable lead stylets were employed to navigate and anchor the lead, which resulted in repetitive screw-in attempts. Therefore, a guiding catheter was developed, which allowed angiography, lead advancement through its lumen, and probatory neurostimulation over its tip. This tool allowed lead delivery within 40 min (n = 5). Neurostimulation via the permanent lead elicited negative dromotropic effects with stimulation frequency, voltage, and impulse duration as determinants of stimulation efficacy.


CONCLUSIONS
Active fixation of a permanent pacing lead inside the RIGP is feasible without thoracotomy. Thereby, ventricular rate control during AF can be achieved with stimulus voltages applied for myocardial electrostimulation.
Gemein
Christopher
C
Department of Cardiology, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
Schauerte
Patrick
P
Hatam
Nima
N
Rana
Obaida R
OR
Saygili
Erol
E
Meyer
Christian
C
Eickholt
Christian
C
Schmid
Michael
M
Knackstedt
Christian
C
Zarse
Markus
M
Mischke
Karl
K
D000818:Animals; D017776:Autonomic Pathways / Q000502:physiology*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004285:Dogs; D006329:Heart Conduction System / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D008297:Male