title: Regional differences in shape and load in normal and diseased hearts studied by three dimensional tagged magnetic resonance imaging.
abstract: OBJECTIVE
  We aimed to characterize regional geometry in relation to load in two groups of patients with hypertrophic cardiomyopathy (HCM) and right ventricular pressure overload (RVPO) in relation to a group of subjects with normal left ventricular (LV) function.
  
  
  BACKGROUND
  Both these diseases are associated with marked changes in LV shape and function, which have not been studied with detailed three dimensional tools.
  
  
  METHODS
  Three dimensional (3D) tagged magnetic resonance imaging (MRI) was used to characterize the 3D geometry and regional stresses of the left ventricles in patients with HCM and RVPO. Curvatures, stresses, wall thickness, and endocardial motion were calculated from surface and volume elements.
  
  
  RESULTS
  Hearts with RVPO exhibited more circumferential and meridional flattening of the septum than normal and HCM hearts. The stress indices were lowest in the HCM hearts, compared to normal and RVPO hearts, due to the larger thicknesses. There was a more significant difference between lateral wall motion and other regional wall motions in the HCM and RVPO hearts as compared to normal hearts.
  
  
  CONCLUSIONS
  It is suggested that curvature and stress mapping by 3D tagged MRI can be used as an important clinical tool for characterizing and distinguishing between healthy and diseased hearts. The results provided here validated previous knowledge on HCM and RVPO known from planary imaging methods.
authors.affiliation: The Heart System Research Center, Julius Silver Institute of Biomedical Engineering, Technion, Haifa, Israel.
authors.forename: Y F
authors.initials: YF
authors.lastname: Petrank
authors.forename: S J
authors.initials: SJ
authors.lastname: Dong
authors.forename: J
authors.initials: J
authors.lastname: Tyberg
authors.forename: S
authors.initials: S
authors.lastname: Sideman
authors.forename: R
authors.initials: R
authors.lastname: Beyar
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000473:pathology* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006321:Heart / Q000033:anatomy & histology / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D018497:Ventricular Dysfunction, Right / Q000473:pathology* / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000502:physiology; D016278:Ventricular Function, Right / Q000502:physiology