Cardiac ElectrophysiologyElectrophysiological ProcessesElectrophysiologic Techniques, CardiacEpicardial MappingModels, CardiovascularArrhythmias, CardiacHeartMyocytes, CardiacHeart Conduction SystemElectrophysiologyVoltage-Sensitive Dye ImagingElectrophysiological PhenomenaElectrocardiographyAction PotentialsAtrioventricular NodeHeart VentriclesCardiac OutputComputer SimulationLong QT SyndromeCatheter AblationMyocardiumHeart RateCardiac Surgical ProceduresDeath, Sudden, CardiacPotassium ChannelsCardiac Pacing, ArtificialAlgorithmsCardiomegalyHeart DiseasesCardiac CatheterizationCardiac TamponadeMyocardial ContractionHeart ArrestTime FactorsHeart FailureHeart AtriaMyoblasts, CardiacCardiomyopathiesPatch-Clamp TechniquesCardiac MyosinsCardiac Imaging TechniquesEchocardiographyDogsCardiac GlycosidesHemodynamicsRats, Sprague-DawleyMyocardial InfarctionCalciumCardiac Output, LowOut-of-Hospital Cardiac ArrestMembrane PotentialsVentricular Function, LeftCardiac VolumeVentricular RemodelingHeart TransplantationVentricular FunctionTroponin IDisease Models, AnimalBlood Pressure