Defibrillators, ImplantableDefibrillatorsElectric CountershockPacemaker, ArtificialEquipment FailureTachycardia, VentricularVentricular FibrillationDeath, Sudden, CardiacArrhythmias, CardiacElectrodes, ImplantedDevice RemovalCardiac Pacing, ArtificialHeart ArrestEquipment SafetyCardiac Resynchronization TherapyEquipment DesignElectrocardiographyElectric InjuriesTreatment OutcomeCentral Nervous System Vascular MalformationsAlternative SplicingCardiac Resynchronization Therapy DevicesProsthesis ImplantationHeart FailureAnti-Arrhythmia AgentsBalloon OcclusionProstheses and ImplantsImplantable NeurostimulatorsFollow-Up StudiesMyocytes, CardiacAmiodaroneEmbolization, TherapeuticEquipment Failure AnalysisCavernous SinusSyncopeCoronary SinusCarotid-Cavernous Sinus FistulaCardiopulmonary ResuscitationTachycardiaTime FactorsSubclavian VeinRetrospective StudiesProspective StudiesVentricular Dysfunction, LeftInfusion Pumps, ImplantableOut-of-Hospital Cardiac ArrestCardiac OutputCardiomyopathiesHeart VentriclesCerebral VeinsHeart BlockCardiac CatheterizationHeartStroke VolumeAtrial FibrillationElectrophysiologic Techniques, CardiacArteriovenous FistulaCranial SinusesTelemetryElectrocardiography, AmbulatoryPolyvinylsFeasibility StudiesForeign-Body MigrationHeart DiseasesVena Cava, SuperiorCardiac ElectrophysiologyHeart Conduction SystemRisk AssessmentCardiac Surgical ProceduresBradycardiaCardiomyopathy, DilatedRisk FactorsBrugada SyndromeCatheterization, PeripheralVenous CutdownEndocardiumDeath, SuddenCatheterizationElectromagnetic PhenomenaRecurrenceDura MaterBundle-Branch BlockPericardiumTachycardia, SupraventricularEchocardiographyCardiography, ImpedanceSurvival RateHeart AtriaPrimary PreventionHeart-Assist DevicesPhlebographyRemote Sensing TechnologyCardiac Output, LowSurvival AnalysisThoracotomyMyocardial InfarctionEmergency Medical ServicesHeart RateHeart Defects, CongenitalMitral Valve Stenosis