Cardiac ElectrophysiologyElectrophysiological ProcessesElectrophysiologic Techniques, CardiacEpicardial MappingArrhythmias, CardiacModels, CardiovascularHeartMyocytes, CardiacHeart Conduction SystemElectrophysiologyVoltage-Sensitive Dye ImagingElectrophysiological PhenomenaElectrocardiographyAction PotentialsAtrioventricular NodeHeart VentriclesCardiac OutputComputer SimulationLong QT SyndromeCatheter AblationMyocardiumHeart RateTreatment OutcomeCardiac Surgical ProceduresDeath, Sudden, CardiacPotassium ChannelsCardiac Pacing, ArtificialTime FactorsAlgorithmsCardiomegalyOutcome Assessment (Health Care)Cardiac CatheterizationHeart DiseasesCardiac TamponadeMyocardial ContractionHeart ArrestHeart FailureRetrospective StudiesProspective StudiesFollow-Up StudiesHeart AtriaPregnancy OutcomeMyocardial InfarctionCardiomyopathiesMyoblasts, CardiacEchocardiographyPatch-Clamp TechniquesCardiac Imaging TechniquesCardiac MyosinsDogsHemodynamicsCardiac GlycosidesRats, Sprague-DawleyOut-of-Hospital Cardiac ArrestCardiac Output, LowVentricular Function, LeftCalciumRisk FactorsMembrane PotentialsHeart TransplantationPrognosisCardiac VolumeVentricular RemodelingTroponin IDisease Models, AnimalVentricular FunctionBlood PressurePredictive Value of TestsHeart Defects, CongenitalCells, CulturedCardiopulmonary ResuscitationStroke Volume