Abstract 16438: Effect of Enzyme Replacement Therapy on Diastolic Function in Patients With Fabry Disease

Abstract

Introduction: The effects of ERT (enzyme replacement therapy) on cardiac manifestations in patients with Fabry disease (FD) are ambiguous. We aimed to investigate the response to ERT using diastolic stress echocardiography (DSE). Hypothesis: Diastolic function of FD would be improved after ERT. Methods: 19 patients with FD who underwent ERT were analyzed. All patients had DSE prior to ERT and post ERT at 1 year follow-up. We measured early diastolic (e’) velocity of the mitral annulus at baseline, 25 Watt (W) and peak exercise. The difference of diastolic reserve (ΔDR) between pre and post ERT was calculated. Diastolic reserve is defined as the change of e’ from baseline to 25W or peak of exercise in DSE. Results: Overall diastolic reserve tends to be improved (ΔDR25W: 0.66±1.36, ΔDRpeak 1.47±2.61) after 1 year of the ERT. However, there was no significant change in left ventricular (LV) wall thickness and LV mass index before and after the ERT. When patients were classified into two groups according to ΔDRpeak (Group 1, n=6, ΔDRpeak ≤0; Group 2, n=13, ΔDRpeak >0), group 2 showed more higher pre-ERT MWE (93.6±3.2 vs 84.8±5.0, p<0.01). The pre-ERT longitudinal strain of LV was better in group 2 compared to group 1 (-14.6±2.6 vs -9.9±2.3m p<0.01). LAVI (44.0±12.9 vs 25.5±8.0, p<0.01), LVEDD (50.8±2.8 vs 46.5 ± 3.0, p<0.01) and LV mass index (204.5±57.5 vs 130.4±45.6, p=0.01) of pre ERT were higher in group 1. Conclusions: Diastolic function of FD was improved generally after ERT in FD patients FD patients who have relatively preserved chamber size and mechanical function before starting ERT showed a better response to ERT. In determining the ERT effect, evaluation of diastolic function is more useful than structural evaluation in patients with Fabry cardiomyopathy.