Carcinoid Heart DiseaseEchocardiographyElectrocardiographyMyocytes, CardiacArrhythmias, CardiacHeartCardiac OutputDeath, Sudden, CardiacCardiac Surgical ProceduresHeart RateHeart DiseasesUltrasonographyCardiac Pacing, ArtificialHeart Conduction SystemMyocardial InfarctionHeart VentriclesUltrasonicsCardiomegalyCardiac CatheterizationUltrasonic TherapyMyocardiumTime FactorsProspective StudiesMyocardial ContractionCardiac TamponadePredictive Value of TestsHigh-Intensity Focused Ultrasound AblationUltrasonography, InterventionalCardiomyopathiesVectorcardiographyHeart ArrestSensitivity and SpecificitySignal Processing, Computer-AssistedElectrocardiography, AmbulatoryHeart FailureBrugada SyndromeMicrobubblesTreatment OutcomeHemodynamicsBlood PressureMyocardial IschemiaUltrasonography, PrenatalFollow-Up StudiesLong QT SyndromeVentricular Function, LeftReproducibility of ResultsRetrospective StudiesCardiac VolumeVentricular FibrillationMyoblasts, CardiacTransducersStroke VolumeRisk FactorsBundle-Branch BlockHeart Defects, CongenitalTroponin ICoronary DiseaseCardiac MyosinsCardiac Imaging TechniquesOut-of-Hospital Cardiac ArrestVentricular Dysfunction, LeftDogsExercise TestModels, CardiovascularTachycardiaCoronary AngiographyTachycardia, VentricularHeart TransplantationHeart AtriaCardiac GlycosidesHeart BlockVentricular RemodelingHeart Function TestsCardiomyopathy, DilatedCardiac Resynchronization TherapyCardiac Output, LowCoronary VesselsAnti-Arrhythmia AgentsTroponin TSyncopeVentricular FunctionHypertrophy, Left VentricularAutonomic Nervous SystemChest PainCardiac Complexes, PrematurePregnancyRisk AssessmentPrognosisCreatine KinaseBradycardiaFetal HeartCardiomyopathy, HypertrophicTelemetryMonitoring, PhysiologicContrast MediaAtrial FibrillationElectrophysiologic Techniques, CardiacPacemaker, ArtificialHeart NeoplasmsPhonocardiography