109 Anderson Fabry disease in CMR: twins by traditional tissue characterization, different by parametric mapping
Authors: Cavallaro C , Barison A , Martini N , Meloni A , Todiere G , Aquaro G , Pepe A 
Published: January 2020

Abstract

Anderson Fabry disease (AFD) is an X-linked recessive lysosomal storage disease, caused by intracellular accumulation of glycosphingolipids due to deficiency of the enzyme α-galactosidase.
The cardiac involvement carries a worse prognosis. Myocardial hypertrophy is the most common manifestation due to the intracellular accumulation of glycosphingolipids in myocytes. With disease progression the deposits are replaced by fibrosis although recent data suggest a chronic inflammation also independently to glycosphingolipids accumulation.
Cardiac magnetic resonance (CMR) by tissue characterization using parametric mapping is a unique technique in evaluating AFD progression and in determining enzyme treatment indications and evolution under therapy.
Heterozygous females are not asymptomatic carriers of the AFD mutation, they have a variable clinical presentation; disease expression in females is the result of random inactivation of the X chromosome. Female patients have a . This case provides an example of Fabry disease in a couple of sisters with a third sister with a diagnosis of AFD with cardiac, hepatic, and renal involvement.
The youngest sister with a positive genetic test was symptomatic for chest pain, without any significant coronary arteries disease by coro CT. The ECG showed atrial fibrillation and sign for LVH confirmed by echocardiography. The traditional CMR study by SSFP cine images and LGE technique showed an increased thickness in the basal infero-lateral wall (15 mm) and the anterior interventricular septum (14 mm) with midwall fibrosis in the basal infero-lateral wall (Fig. 1 A, B).
The oldest sister with a positive genetic test was asyntomatic in AF. ECG and ECOC were aspecific. The traditional CMR study by SSFP cine images and LGE technique showed the same finding of the youngest sister (Fig. 2 A, B)
By T1 mapping based on the normal cut off values of the Lab the older sister reported a short T1 global value (915 ms) and short T1 values in all segment with exception of lateral wall, mid and distal inferior segments and distal septum (Figure 1 C). Despite the presence of positive LGE in the basal infero-lateral wall the T1 value was normal in this segment due to a pseudo normalization related to the sphingolipid accumulation. Based on the CMR report she started the enzyme replacement therapy and the CMR follow was planned at 1 year.
Conversely, the younger woman reported a long T1 value only in the basal infero-lateral wall with normal T1 value in all the other segments (Figure 2 C). The positive LGE in the basal infero-later segment (oedema/fibrosis) justifies the long T1 value in this no thickness segment. Based on the CMR report she did not start enzyme replacement therapy.

Conclusion
The case of this family show how quantitative parametric mapping could be a unique tool for the clinicians to adjust the therapy and plan the follow up of patients affected by AFD with cardiac involvement.
Abstract 109 Figure.