CardiomyopathiesArrhythmias, CardiacCardiomyopathy, RestrictiveCardiomyopathy, DilatedCardiomyopathy, HypertrophicCardiomyopathy, Hypertrophic, FamilialArrhythmia, SinusMyocardiumArrhythmogenic Right Ventricular DysplasiaElectrocardiographyChagas CardiomyopathyDeath, Sudden, CardiacIsolated Noncompaction of the Ventricular MyocardiumMyocytes, CardiacSarcomeresHeart DiseasesHeart VentriclesMyocarditisTachycardia, VentricularCardiac MyosinsAnti-Arrhythmia AgentsHeartHeart FailureVentricular FibrillationGenetic TestingMutationEndomyocardial FibrosisEchocardiographyDesminCardiomegalyVentricular Premature ComplexesMitochondrial DiseasesMyocardial ContractionMyocardial IschemiaHeart Conduction SystemTachycardiaSarcoglycansElectrocardiography, AmbulatoryDisease Models, AnimalVentricular Dysfunction, LeftPhenotypeCardiac Complexes, PrematureMagnetic Resonance Imaging, CineMitochondria, HeartTroponin TPedigreeLong QT SyndromeMyosin Heavy ChainsAtrial FibrillationSportsTachycardia, SupraventricularMutation, MissenseHeart RateVentricular Function, LeftMyofibrilsElectrophysiologic Techniques, CardiacMutant ProteinsAtrial FlutterDefibrillators, ImplantableCalciumFibrosisCatheter AblationTime FactorsStroke VolumeDiastoleDystrophinHeart TransplantationVentricular RemodelingCardiac Pacing, ArtificialHypertrophy, Left VentricularMuscle ProteinsFlecainideMice, TransgenicPredictive Value of TestsRisk FactorsVentricular DysfunctionTorsades de PointesContrast MediaNAV1.5 Voltage-Gated Sodium ChannelDogsRetrospective StudiesDiabetic CardiomyopathiesElectric CountershockAmiodaroneAction PotentialsGenetic Predisposition to DiseaseHeart AtriaMagnetic Resonance ImagingBiopsyDigitalis GlycosidesPrognosisCase-Control StudiesBradycardiaModels, CardiovascularAconitineMyocardial InfarctionDeath, SuddenCardiovascular DiseasesAtrial Premature ComplexesBody Surface Potential Mapping