Left ventricular T2 distribution in Duchenne muscular dystrophy. J Cardiovasc Magn Reson 2010 Mar 18;12(1):14
Date
03/20/2010Pubmed ID
20298602Pubmed Central ID
PMC2846924DOI
10.1186/1532-429X-12-14Scopus ID
2-s2.0-77952529797 (requires institutional sign-in at Scopus site) 29 CitationsAbstract
BACKGROUND: Although previous studies have helped define the natural history of Duchenne muscular dystrophy (DMD)-associated cardiomyopathy, the myocardial pathobiology associated with functional impairment in DMD is not yet known.The objective of this study was to assess the distribution of transverse relaxation time (T2) in the left ventricle (LV) of DMD patients, and to determine the association of myocardial T2 heterogeneity to the severity of cardiac dysfunction. DMD patients (n = 26) and normal control subjects (n = 13) were studied by cardiovascular magnetic resonance (CMR). DMD subject data was stratified based on subject age and LV ejection fraction (EF) into the following groups: A (<12 years old, n = 12); B (>or=12 years old, EF <or= 55%, n = 8) and C (>or=12 years old, EF = 55%, n = 6). Controls were also stratified by age into Groups N1 (<12 years, n = 6) and N2 (>12 years, n = 5). LV mid-slice circumferential myocardial strain (epsilon cc) was calculated using tagged CMR imaging. T2 maps of the LV were generated for all subjects using a black blood dual spin echo method at two echo times. The full width at half maximum (FWHM) was calculated from a histogram of LV T2 distribution constructed for each subject.
RESULTS: In DMD subject groups, FWHM of the T2 histogram rose progressively with age and decreasing EF (Group A FWHM= 25.3 +/- 3.8 ms; Group B FWHM= 30.9 +/- 5.3 ms; Group C FWHM= 33.0 +/- 6.4 ms). Further, FWHM was significantly higher in those with reduced circumferential strain (|epsilon cc| <or= 12%) (Group B, and C) than those with |epsilon cc| > 12% (Group A). Group A FWHM was not different from the two normal groups (N1 FWHM = 25.3 +/- 3.5 ms; N2 FWHM= 24.0 +/- 7.3 ms).
CONCLUSION: Reduced EF and epsilon cc correlates well with increased T2 heterogeneity quantified by FWHM, indicating that subclinical functional impairments could be associated with pre-existing abnormalities in tissue structure in young DMD patients.
Author List
Wansapura JP, Hor KN, Mazur W, Fleck R, Hagenbuch S, Benson DW, Gottliebson WMMESH terms used to index this publication - Major topics in bold
AdolescentAdult
Age Factors
Cardiomyopathies
Case-Control Studies
Child
Child, Preschool
Cross-Sectional Studies
Disease Progression
Humans
Linear Models
Magnetic Resonance Imaging, Cine
Male
Middle Aged
Muscular Dystrophy, Duchenne
Predictive Value of Tests
Severity of Illness Index
Stroke Volume
Ventricular Dysfunction, Left
Ventricular Function, Left
Young Adult
