Abstract 12538: Non-Pharmacologic Control of Post-Operative Supraventricular Arrhythmias Using AV Nodal Fat Pad Stimulation in a Young Canine Open Heart Surgical Model
Introduction: Supraventricular arrhythmias frequently complicate the post-operative recovery from open heart surgery (OHS) in children (junctional ectopic tachycardia (JET)) and atrial tachyarrhythmias), and can be difficult to manage. Medical treatment of JET can result in significant morbidity. Our goal was to develop a non-pharmacologic approach using autonomic stimulation of selective fat pad (FP) regions of the heart in a young canine model of OHS to control two common post-operative supraventricular arrhythmias.
Methods: Seven mongrel dogs, varying in age from 5-8 months of age and weighting 21 ± 4 kg, underwent OHS replicating a non-transannular approach to tetralogy of Fallot repair. Neural stimulation of the right inferior FP was used to control the ventricular response to supraventricular arrhythmias, conducting through the AV node (AVN) or occurring in and around the proximal conduction system, after suturing a custom electrode to the right inferior FP.
Results: Right inferior FP stimulation decreased baseline AV nodal conduction without altering sinus cycle length (CL). AVN Wenckebach cycle length prolonged from 270 ± 33 to 352 ± 89 msec, p=0.02. Atrial fibrillation was induced in 6 animals to simulate a rapid atrial tachyarrhythmia. FP stimulation slowed the ventricular response rate from 148 ± 36 to 56 ± 25 bpm, p< 0.01. Post-operative JET occurred in 6 dogs. FP stimulation slowed the ventricular rate during post-operative JET from 148 ± 34 to 101 ± 33 bpm, p = 0.03, and restored sinus rhythm in 5/6 dogs. Figure one reveals the effect of FP stimulation during JET, slowing the ventricular rate (172 to 146 bpm) and converting the arrhythmia to sinus rhythm.
Conclusion: Right inferior FP stimulation has a selective effect on the AVN, and slowed the ventricular rate during post-operative JET and atrial tachyarrhythmias in our young canine OHS model. FP stimulation may be a useful new technique for managing children with JET and atrial tachyarrhythmias after OHS.
- Supraventricular tachycardia
- Arrhythmias, treatment of
- Autonomic nervous system
- Cardiac surgery
- © 2012 by American Heart Association, Inc.