Torsades de PointesArrhythmias, CardiacAcetanilidesLong QT SyndromeAction PotentialsAnti-Arrhythmia AgentsMyocytes, CardiacModels, CardiovascularBenzylaminesHeart Conduction SystemVentricular Premature ComplexesHeart VentriclesHypokalemiaCalcium Channels, L-TypeRabbitsVentricular FunctionIsoproterenolDogsPurkinje FibersSodium Channel BlockersCalcium SignalingNAV1.5 Voltage-Gated Sodium ChannelCalcium-Calmodulin-Dependent Protein Kinase Type 2Sodium ChannelsHeartPatch-Clamp TechniquesCalciumSulfonamidesSodium-Calcium ExchangerPotassium ChannelsElectrocardiographyCardiac Pacing, ArtificialRyanodineNifedipineElectrophysiologyComputer SimulationGuinea PigsAdrenergic beta-AgonistsPotassiumPiperazinesCalcium Channel BlockersMembrane PotentialsHydrogen PeroxideMyocardiumIon ChannelsDisease Models, AnimalTime FactorsKinetics