Circadian RhythmHeartHeart RateDefibrillators, ImplantableArrhythmias, CardiacEuropeAtrial FibrillationPacemaker, ArtificialCardiologySocieties, MedicalFractalsElectrocardiography, AmbulatoryCardiac Imaging TechniquesCardiac Pacing, ArtificialElectrocardiographyElectric CountershockHeart Conduction SystemCatheter AblationAnti-Arrhythmia AgentsDevice RemovalHeart FailureSignal Processing, Computer-AssistedHealth Care SurveysHeart DiseasesCardiac Resynchronization TherapyHeart Defects, CongenitalHeart TransplantationTreatment OutcomeDeath, Sudden, CardiacTachycardia, VentricularPractice Guidelines as TopicHeart AtriaFetal HeartPeriodicityPhysician's Practice PatternsBiological ClocksSuprachiasmatic NucleusHeart ValvesHeart BlockRisk FactorsPeriod Circadian ProteinsCircadian Rhythm Signaling Peptides and ProteinsTime FactorsActivity CyclesPhotoperiodSleep Disorders, Circadian RhythmMyocardiumCircadian ClocksCLOCK ProteinsAlpha RhythmMyocardial ContractionHeart Arrest, InducedHeart Function TestsARNTL Transcription FactorsMyocardial IschemiaMyocytes, CardiacHemodynamicsHeart ArrestLightChronobiology DisordersCoronary DiseaseMonitoring, PhysiologicDarknessMotor ActivityVentricular Function, LeftEchocardiographyProspective StudiesCardiac Output, LowBody TemperatureCardiomyopathy, DilatedStroke VolumePerfusionRheumatic Heart DiseaseRats, Sprague-DawleyDogsFollow-Up StudiesHeart Rate, FetalCardiomegalyHeart SeptumCardiotonic AgentsAdrenergic beta-AntagonistsCardiomyopathiesVentricular Dysfunction, LeftRats, WistarSleepHeart, ArtificialHeart Failure, SystolicMyocardial InfarctionAction PotentialsAutonomic Nervous SystemChronic DiseaseHeart InjuriesMyocardial Reperfusion InjuryDisease Models, AnimalTelemetryCryptochromesHeart Valve ProsthesisBeta RhythmRespirationAtrioventricular Node