Atrioventricular NodeBradycardiaTachycardia, Atrioventricular Nodal ReentryBundle of HisHeart Conduction SystemSinoatrial NodeHeart BlockCatheter AblationCardiac Pacing, ArtificialElectrocardiographyTachycardia, ParoxysmalLymph NodesTachycardiaElectrophysiologic Techniques, CardiacTachycardia, SupraventricularWolff-Parkinson-White SyndromeHeart AtriaTachycardia, Ectopic JunctionalSick Sinus SyndromeHeart RateVagus NerveAtrial FibrillationAtrial FunctionElectrocoagulationPacemaker, ArtificialAtrial FlutterAtrioventricular BlockRefractory Period, ElectrophysiologicalUltimobranchial BodyHeart SeptumAnti-Arrhythmia AgentsTachycardia, Ectopic AtrialRabbitsArrhythmias, CardiacElectrophysiologyDogsRadio WavesHeart VentriclesPurkinje FibersAction PotentialsHeartAtropineConnexinsBody Surface Potential MappingFollow-Up StudiesLymph Node ExcisionModels, CardiovascularApneaTime FactorsHeart NeoplasmsMicroelectrodesAdenosineMyocardiumTricuspid ValveSentinel Lymph Node BiopsyTreatment OutcomeElectric StimulationHypotension