Heart SeptumHeartMusclesMyocardiumMuscle ProteinsMyocytes, CardiacMuscle, SkeletalHeart RateSeptum of BrainMuscle, SmoothVentricular SeptumMuscle Fibers, SkeletalMyocardial ContractionSeptum PellucidumPapillary MusclesMuscle, Smooth, VascularAtrial SeptumMuscle ContractionMuscle DevelopmentNasal SeptumHeart FailureHeart DiseasesCardiac OutputCalciumMyofibrilsSarcomeresHeart VentriclesHeart Defects, CongenitalHeart TransplantationMuscle Fibers, Fast-TwitchFetal HeartTime FactorsHeart AtriaCardiomegalyMuscle Fibers, Slow-TwitchCardiac Surgical ProceduresRabbitsArrhythmias, CardiacMuscle FatigueMitochondria, MuscleMuscle DenervationCardiomyopathiesTroponin CDeath, Sudden, CardiacRats, Sprague-DawleyDogsMyocytes, Smooth MuscleMuscle CellsTroponinTroponin ICells, CulturedCardiac Pacing, ArtificialHeart ValvesMyosin Heavy ChainsCardiac MyosinsEchocardiographySarcoplasmic ReticulumSarcolemmaMuscle RelaxationRats, WistarNeck MusclesIsometric ContractionOculomotor MusclesMuscle, StriatedModels, CardiovascularHemodynamicsRNA, MessengerRyanodine Receptor Calcium Release ChannelMuscle SpindlesRespiratory MusclesVentricular Function, LeftMuscle WeaknessCardiac CatheterizationMolecular Sequence DataGuinea PigsMyosinsTropomyosinHeart ArrestIsoproterenolActinsCardiomyopathy, DilatedCreatine KinaseCardiotonic AgentsMuscular DiseasesMyocardial IschemiaTroponin TElectric StimulationMicroscopy, ElectronAction PotentialsDisease Models, AnimalHeart Function TestsMyocardial InfarctionDystrophinCardiac Output, LowKineticsAbdominal MusclesMice, Inbred C57BLConnectinHeart Conduction SystemQuadriceps Muscle