Coronary SinusEchocardiographyCoronary VesselsEchocardiography, TransesophagealCoronary AngiographyCoronary CirculationEchocardiography, DopplerEchocardiography, Three-DimensionalCoronary Artery DiseaseSinus of ValsalvaEchocardiography, StressEchocardiography, Doppler, ColorAngioplasty, Balloon, CoronaryCoronary StenosisCoronary DiseaseElectrocardiographyHeart AtriaCoronary Artery BypassCardiac CatheterizationCardiac Pacing, ArtificialCranial SinusesMaxillary SinusCoronary Vessel AnomaliesHeart VentriclesParanasal SinusesVentricular Function, LeftEchocardiography, Doppler, PulsedDobutamineVentricular Dysfunction, LeftMitral ValveVena Cava, SuperiorCoronary AneurysmCavernous SinusMyocardial InfarctionCatheter AblationHemodynamicsCoronary VasospasmDogsMyocardiumHeartStroke VolumeCarotid SinusTreatment OutcomePacemaker, ArtificialProspective StudiesPredictive Value of TestsMyocardial IschemiaAtrial FibrillationFrontal SinusMitral Valve InsufficiencyParanasal Sinus DiseasesHeart DiseasesHeart Conduction SystemSphenoid SinusFollow-Up StudiesFeasibility StudiesBlood Flow VelocityHeart Septal Defects, AtrialTime FactorsHeart SeptumMyocardial ContractionDiastoleHeart Defects, CongenitalSensitivity and SpecificityCoronary ThrombosisHeart FailureElectrophysiologic Techniques, CardiacAtrioventricular NodeExercise TestSystoleAtrial FlutterObserver VariationDipyridamoleHeart Arrest, InducedTricuspid ValveContrast MediaSick Sinus SyndromeRisk FactorsTomography, X-Ray ComputedSinus Thrombosis, IntracranialCardiac Surgical ProceduresHeart Valve DiseasesAortic ValveAtrial SeptumAtrial FunctionFetal HeartCardiotonic AgentsDilatation, PathologicEthmoid SinusTachycardia, Sinoatrial Nodal ReentryCoronary OcclusionCoronary RestenosisBlood PressureReproducibility of ResultsElectrodes, ImplantedPulmonary VeinsProsthesis ImplantationCardiac Resynchronization Therapy DevicesCardiomyopathiesBundle of His