Cardiac Magnetic Resonance in Fabry Disease: Morphological, Functional, and Tissue Features

Abstract

Fabry disease (FD) is an X-linked inheritable storage disease caused by a deficiency of alpha-galactosidase causing lysosomal overload of sphingolipids. FD cardiomyopathy is characterized by left ventricular (LV) hypertrophy and should be considered in differential diagnosis with all the other causes of LV hypertrophy. An early diagnosis of FD is very important because the enzyme replacement therapy (ERT) may change the fate of patients by blocking both cardiac and systemic involvement and improving prognosis. Diagnosis may be relatively easy in young patients with the typical signs and symptoms of FD, but in male patients with late onset of disease and in females, diagnosis may be very challenging. Morphological and functional aspects are not specific to FD, which cannot be diagnosed or excluded by echocardiography. Cardiac magnetic resonance (CMR) with tissue characterization capability is an accurate technique for the differential diagnosis of LV hypertrophy. The finding of decreased myocardial T1 value in LV hypertrophy is specific to FD. Late gadolinium enhancement (LGE) is found in the late stage of the disease, but it is useful to predict the cardiac response to ERT and to stratify the prognosis.

Keywords: Fabry disease; T1 mapping; cardiac magnetic resonance; feature tracking; late gadolinium enhancement.

Figure 1

CMR of Fabry disease. Images of a 65-year-old female with Fabry disease and concentric left ventricular hypertrophy and typical CMR presentation. On post contrast image (four-chamber and short axis views in left panels), area of late gadolinium enhancement (LGE) is found in the mid-wall layer of the inferolateral wall, which is the typical site of LGE in Fabry disease. At T1 mapping (short axis views in right panels) a diffuse decrease of native myocardial T1 (blue areas) is found.

Figure 2

Example of pseudo-normalization of T1 in Fabry disease. CMR images of a 70-year-old male with late onset Fabry disease. The patten of LV hypertrophy is asymmetric, with wall thickening apparently limited to the basal septum. The set of three short axis T1 mapping showed myocardial T1 values within the normality range. On post-contrast images, a diffuse LGE is found in the lateral wall, apex, and even in the anteroseptal wall. Fortunately, T1 mapping was also acquired in four-chamber views and a small area of decreased T1 values was found in the basal septum, corresponding to the region of hypertrophy and with only a small island of LGE. This finding raised the suspicion of Fabry disease that was eventually confirmed by enzymatic test and genetic evaluation.