Coronary SinusCoronary VesselsMuscle ContractionCoronary AngiographyCoronary CirculationCoronary Artery DiseaseSinus of ValsalvaAngioplasty, Balloon, CoronaryCoronary StenosisCoronary Artery BypassCranial SinusesMaxillary SinusCoronary DiseaseIsometric ContractionCardiac Pacing, ArtificialParanasal SinusesCavernous SinusCoronary Vessel AnomaliesElectrocardiographyCoronary AneurysmMyocardial ContractionDogsVena Cava, SuperiorHeart AtriaCarotid SinusCoronary VasospasmCatheter AblationCardiac CatheterizationFrontal SinusParanasal Sinus DiseasesSphenoid SinusPacemaker, ArtificialHeart Conduction SystemUterine ContractionMyocardiumTime FactorsHeartMyocardial InfarctionTreatment OutcomeAtrial FibrillationAtrioventricular NodeElectrophysiologic Techniques, CardiacCoronary ThrombosisHeart Arrest, InducedSinus Thrombosis, IntracranialHemodynamicsSick Sinus SyndromeAtrial FlutterEthmoid SinusMyocardial IschemiaTachycardia, Sinoatrial Nodal ReentryCoronary RestenosisAtrial FunctionHeart VentriclesBundle of HisMuscle, SmoothCoronary OcclusionElectrodes, ImplantedFollow-Up StudiesProspective StudiesCardiac Resynchronization Therapy DevicesPercutaneous Coronary InterventionElectric StimulationVasoconstrictionTomography, X-Ray ComputedCardiac CathetersRisk FactorsParanasal Sinus NeoplasmsPhlebographyVasodilator AgentsEchocardiographyTachycardia, Atrioventricular Nodal ReentrySinoatrial NodeTachycardia, SupraventricularVeinsProsthesis ImplantationAtrial SeptumBlood PressureBlood Flow VelocityTachycardia, SinusDilatation, PathologicCoronary Care UnitsHeart FailureEchocardiography, TransesophagealWolff-Parkinson-White SyndromeBody Surface Potential MappingPredictive Value of TestsFluoroscopyAcetylcholineNorepinephrineFeasibility StudiesVasodilationOxygen ConsumptionMuscle, Smooth, VascularStentsAdenosineCalciumTachycardia, ParoxysmalSwineHeart Rate