title: Stress hypoperfusion and tissue injury in hypertrophic cardiomyopathy: spatial characterization using high-resolution 3-tesla magnetic resonance imaging.
abstract: BACKGROUND
  Ischemia and tissue injury are common in patients with hypertrophic cardiomyopathy. Cardiovascular magnetic resonance imaging offers combined evaluations of each phenomenon at sufficiently high resolution to examine transmural spatial distribution. In this prospective cohort study, we examine the spatial distribution of stress perfusion abnormalities and tissue injury in patients with hypertrophic cardiomyopathy.
  
  
  RESULTS
  One hundred consecutive patients with hypertrophic cardiomyopathy underwent cardiovascular magnetic resonance imaging. Cine, stress perfusion, late gadolinium enhancement, and T2-weighted imaging techniques were used. Each was spatially coregistered according to predefined segmental and subsegmental models and was blindly analyzed for abnormalities using validated techniques. Spatial associations among stress perfusion, late gadolinium enhancement, and T2 imaging were made at segmental and subsegmental levels. Of the 100 patients studied, the phenotype was septal in 86 and apical in 14. Late gadolinium enhancement imaging was abnormal in 79 patients (79%). Eighty-six patients met prespecified safety criteria to undergo stress perfusion, and ischemia was identified in 46 patients (57%). T2 imaging was available in 81 patients and was abnormal in 19 (29%). The dominant distribution of all 3 findings was to segment with hypertrophy. Subsegmental analysis revealed geographic dominance of ischemia within the subendocardial zones. However, this zone was most commonly spared from late gadolinium enhancement and T2 abnormalities, typically seen in midwall and subepicardial zones.
  
  
  CONCLUSIONS
  Inducible hypoperfusion is a common finding in hypertrophic cardiomyopathy and is typically identified within segments exhibiting imaging markers of tissue injury. However, the respective transmural dominance of these phenomena seems distinct. Alternate factors contributing to a regional susceptibility to tissue injury are deserving of further study.
authors: Department of Medicine, Schulich School of Medicine and Dentistry, Imaging Research Laboratories, Robarts Research Institute, and Lawson Health Research Institute, University of Western Ontario, Ontario, Canada.
authors: Chung Chun
authors: CC
authors: Tyan
authors: Sarah
authors: S
authors: Armstrong
authors: David
authors: D
authors: Scholl
authors: John
authors: J
authors: Stirrat
authors: Kimberly
authors: K
authors: Blackwood
authors: Omar
authors: O
authors: El-Sherif
authors: Terry
authors: T
authors: Thompson
authors: Gerald
authors: G
authors: Wisenberg
authors: Frank S
authors: FS
authors: Prato
authors: Aaron
authors: A
authors: So
authors: Ting Yim
authors: TY
authors: Lee
authors: Maria
authors: M
authors: Drangova
authors: James A
authors: JA
authors: White
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D016009:Chi-Square Distribution; D003287:Contrast Media; D003326:Coronary Circulation; D005355:Fibrosis; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009205:Myocarditis / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology; D009206:Myocardium / Q000473:pathology*; D010641:Phenotype; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013318:Stroke Volume; D014665:Vasodilator Agents; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media; D014665:Vasodilator Agents