Cardiac VolumeEchocardiography, Four-DimensionalFetal HeartEchocardiography, Three-DimensionalHeartStroke VolumeMyocytes, CardiacCardiac OutputBlood VolumeCardiac Surgical ProceduresArrhythmias, CardiacDeath, Sudden, CardiacCardiomegalyHypertrophyHemodynamicsVentricular PressureModels, CardiovascularHypertrophy, Left Ventricular