P799 The echocardiographic and clinical characteristics of Fabry patients without overt left ventricular hypertrophy but progressing despite on enzyme replacement therapy

Abstract

Abstract Background Fabry disease (FD) is X-linked genetic disorder caused by the deficiency or absent activity of lysosomal α- galactosidase. When the heart is involved, progressive left ventricular hypertrophy (LVH) is the key feature. Although, LVH is not present in all subjects, some of them progress with LVH despite enzyme replacement therapy (ERT). The present study aimed to evaluate the characteristics of patient of FD without overt LVH, but progresses with their left ventricular mass index (LVMI). Method : This study includes subjects carrying genetic mutations for FD without LVH (n = 12) in a single tertiary center. ‘Decreasing LVMI group (Group1)’ was defined when pre-ERT LVMI minus last LVMI value obtained by echocardiography was positive, and when negative, defined as ‘Increasing LVMI group (Group 2)’. The baseline characteristics and echocardiographic parameters including global strain was analyzed. Result : Total 6 patients were classified as Group 1 and 2 each. The median age at diagnosis for male was 21 vs 27 for each group, and 21 vs 31 for female. The median follow-up duration was 4.0 vs 5.7 yr. The antibody formation for replaced enzyme was 3 for Group 2 and any family member who developed overt LVH was much 1 vs 3 for group 1 vs 2. Initial 3 plane GLS was worse and showed trend to drop in Group 2. Conclusion : In the Fabry patients get worse with their LVMI but still not developed overt LVH despite enzyme replacement therapy, there are some clinical and echo-parameter difference. These findings could suggest insufficient enzyme replacement therapy. Group 1 (n = 6) Group 2 (n = 6) Female/Male 4/2 3/3 Age of at Dx (Female) (median) 21 28 Age of at Dx (Male) (median) 21 31 F/U duration (median) 4.0 yrs 5.7 yrs Antibody formation 0 3 Any Overt LVH family Genotype c.56T > C c.40-11T > A, 782_delG, c.658C > T Initial LVMI (Median) 98.2g/m2 70.9g/m2 Initial GLS (3P) -19 -17.8 Continuously elevated LysoGb3 2 4 Proteinuria >300mg 1 3 (1 preparing HD)