title: Myocardial impairment detected by late gadolinium enhancement in hypertrophic cardiomyopathy: comparison with 99mTc-MIBI/tetrofosmin and 123I-BMIPP SPECT.
abstract: OBJECTIVE
  Myocardial fibrosis is considered to be an important factor in myocardial dysfunction and sudden cardiac death in hypertrophic cardiomyopathy (HCM). The purpose of this study was to compare myocardial fibrosis detected by late gadolinium enhancement (LGE) on cardiac MRI with myocardial perfusion and fatty acid metabolism assessed by single photon emission computed tomography in HCM.
  
  
  METHODS
  We retrospectively evaluated 20 consecutive HCM patients (female, 7; mean age, 53.4 years) who underwent LGE, technetium-99m methoxyisobutylisonitrile/tetrofosmin (99mTc-MIBI/tetrofosmin), and iodine-123 beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP) imaging. We calculated the myocardium-to-lumen signal ratio (M/L) for LGE in 17 segments based on the American Heart Association statement. Scoring of 99mTc-MIBI/tetrofosmin (PI) and 123I-BMIPP (BM) was performed for each segment using a 5-point scale (0, normal; 4, highly decreased).
  
  
  RESULTS
  Nineteen of 20 patients (95%) and 153 of 340 segments (45%) showed LGE. M/Ls were 0.42±0.16, 0.55±0.17, and 0.65±0.24 in PI0/BM0, PI0/BM1-4 and PI1-4/BM1-4, respectively. All M/Ls were significantly higher than that of a normal control (0.34±0.14) (p<0.001).
  
  
  CONCLUSIONS
  Myocardial fibrosis in HCM can occur despite normal perfusion and fatty acid metabolism, and is more strongly associated with disorders of fatty acid metabolism than with perfusion abnormalities. M/L may be a useful indicator of disease severity.
authors.affiliation: Department of Radiology, National Cerebral and Cardiovascular Center 5-7-1 Fujishiro-dai, Suita, 565-8565 Osaka, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Hashimura
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kiso
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yamada
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kono
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Morita
authors.forename: Kazuto
authors.initials: K
authors.lastname: Fukushima
authors.forename: Masahiro
authors.initials: M
authors.lastname: Higashi
authors.forename: Teruo
authors.initials: T
authors.lastname: Noguchi
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naito
authors.forename: Kazuro
authors.initials: K
authors.lastname: Sugimura
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D005227:Fatty Acids / Q000378:metabolism; D005260:Female; D005355:Fibrosis; D019786:Gadolinium DTPA; D006801:Humans; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D005227:Fatty Acids; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C049338:iodofiltic acid; C078700:technetium tc-99m tetrofosmin; D019786:Gadolinium DTPA