T₁ mapping with cardiovascular MRI is highly sensitive for Fabry disease independent of hypertrophy and sex.

BACKGROUND: Fabry disease (FD) is an X-linked disorder of lysosomal metabolism affecting multiple organs with cardiac disease being the leading cause of death. Current imaging evaluations of the heart are suboptimal. The goals of the current study are to evaluate the potential of quantitative T₁ mapping with cardiovascular MRI as a disease-specific imaging biomarker. METHODS AND
RESULTS: A total of 31 patients with FD, 23 healthy controls, and 21 subjects with concentric remodeling or hypertrophy underwent cardiovascular MRI to measure left ventricular (LV) morphology, function, delayed enhancement, as well as myocardial T₁ values, and derived parameters (extracellular volume). All subjects had LV ejection fraction >50% and similar volumes. FD and concentric remodeling or hypertrophy had similarly increased mass, wall thickness, and mass/volume as compared with controls. A total of 16 of 31 FD subjects and 10 of 21 concentric remodeling or hypertrophy subjects had LV hypertrophy. Noncontrast myocardial T₁ values were substantially lower in FD as compared with controls and concentric remodeling or hypertrophy (1070 ± 50, 1177 ± 27, and 1207 ± 33 ms, respectively; P<0.001), but extracellular volume was similar in all groups (21.7 ± 2.4%, 22.2 ± 3.1%, and 21.8 ± 3.9%, respectively). Single-voxel NMR spectroscopy in 4 FD and 4 healthy control subjects showed a significant negative linear relationship between lipid content and noncontrast T₁ values (r=-0.9; P=0.002). Female subjects had lower LV mass and wall thickness, longer myocardial T₁ values and larger extracellular volume suggesting a key sex difference in cardiac remodeling.
CONCLUSIONS: Reduced noncontrast myocardial T₁ values are the most sensitive and specific cardiovascular MRI parameter in patients with FD irrespective of sex and LV morphology and function.