title: Trabeculated (noncompacted) and compact myocardium in adults: the multi-ethnic study of atherosclerosis.
abstract: BACKGROUND
  A high degree of noncompacted (trabeculated) myocardium in relationship to compact myocardium (trabeculated to compact myocardium [T/M] ratio >2.3) has been associated with a diagnosis of left ventricular noncompaction (LVNC). The purpose of this study was to determine the normal range of the T/M ratio in a large population-based study and to examine the relationship to demographic and clinical parameters.
  
  
  RESULTS
  The thickness of trabeculation and the compact myocardium were measured in 8 left ventricular regions on long axis cardiac MR steady-state free precession cine images in 1000 participants (551 women; 68.1±8.9 years) of the Multi-Ethnic Study of Atherosclerosis cohort. Of 323 participants without cardiac disease or hypertension and with all regions evaluable, 140 (43%) had a T/M ratio >2.3 in at least 1 region; in 20 of 323 (6%), T/M >2.3 was present in >2 regions. A multivariable linear regression model revealed no association of age, sex, ethnicity, height, and weight with maximum T/M ratio in participants without cardiac disease or hypertension (P>0.05). In the entire cohort (n=1000), left ventricular ejection fraction (β=-0.02/%; P=0.015), left ventricular end-diastolic volume (β=0.01/mL; P<0.0001), and left ventricular end-systolic volume (β=0.01/mL; P<0.001) were associated with maximum T/M ratio in adjusted models, whereas there was no association with hypertension or myocardial infarction (P>0.05). At the apical level, T/M ratios were significantly lower when obtained on short- compared with long-axis images (P=0.017).
  
  
  CONCLUSIONS
  A ratio of T/M of >2.3 is common in a large population-based cohort. These results suggest re-evaluation of the current cardiac MR criteria for left ventricular noncompaction may be necessary.
authors.affiliation: Radiology and Imaging Sciences and National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Nadine
authors.initials: N
authors.lastname: Kawel
authors.forename: Marcelo
authors.initials: M
authors.lastname: Nacif
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Arai
authors.forename: Antoinette S
authors.initials: AS
authors.lastname: Gomes
authors.forename: W Gregory
authors.initials: WG
authors.lastname: Hundley
authors.forename: W Craig
authors.initials: WC
authors.lastname: Johnson
authors.forename: Martin R
authors.initials: MR
authors.lastname: Prince
authors.forename: R Brandon
authors.initials: RB
authors.lastname: Stacey
authors.forename: João A C
authors.initials: JA
authors.lastname: Lima
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000175:diagnosis* / Q000208:ethnology*; D015331:Cohort Studies; D003287:Contrast Media; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D056830:Isolated Noncompaction of the Ventricular Myocardium / Q000175:diagnosis*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D015588:Observer Variation; D011159:Population Surveillance; D012680:Sensitivity and Specificity; D016277:Ventricular Function, Left
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA