Agalsidase Beta Long-Term Treatment Outcome for Fabry Disease Patients With IVS4 Mutation in Taiwan

Inclusion Criteria: \- Provide signed informed consent. Cohort 1: * Male or female Fabry disease patient with documented GLA IVS4 in medical record. * Age ≥ 18 years old at the time of signing informed consent. * The maximum proportion of female is 20% of cohort 1. * Patient who has received agalsidase beta treatment for at least 6 months. * The data of LVMI, LPWT, IVST and blood lyso-Gb3 concentration are all available within 6 months prior to agalsidase beta treatment initiation. Cohort 2: * Male or female Fabry disease patient with documented GLA IVS4 in medical record. * Age ≥ 18 years old at the time of signing informed consent. * The maximum proportion of female is 20% of cohort 2. * Patient who plans to apply for the National Health Insurance Reimbursement for agalsidase beta medication. * The data of LVMI, LPWT, IVST and blood lyso-Gb3 concentration are all available within 6 months prior to agalsidase beta treatment initiation. Cohort 3: * Male or female Fabry disease patients with documented GLA IVS4 mutation in medical record. * Male patient is aged ≥ 30 years old and female patient is aged ≥ 40 years old at the time of signing informed consent. * The maximum proportion of female is 20% of cohort 3. * Patient who has never received agalsidase alpha or agalsidase beta treatment (ERT-naïve). * Elevated blood lyso-Gb3. * At least ONE of the following conditions documented in medical record: 1. cardiac parameter abnormalities (e.g. via imaging, electrophysiology, or biomarker); 2. at least one FD-related sign/symptom. * The data of LVMI, LPWT, IVST and blood lyso-Gb3 concentration are all available within 6 months. * Patients who are expected not to receive ERT or FD-specific treatment per investigator's judgement. Exclusion Criteria: * Any condition that, in the opinion of the Investigator, may interfere with patient's participation in the study, such as life expectancy of less than 6 months (e.g. diagnosed with malignancy, CAD) * Fabry patients who have severe heart disease (NYHA Class IV) or severe myocardial fibrosis per investigator judgement * Known non-Fabry disease infiltrative cardiomyopathy including amyloidosis * Known non-GLA genetic (e.g., sarcomeric, metabolic mutations) hypertrophic cardiomyopathy. * Patients who are receiving any Fabry disease-specific treatment (enzyme replacement therapy, chaperone therapy, substrate reduction therapy, or gene therapy) other than agalsidase beta for Fabry disease * Pregnancy or suspected pregnancy * Patient diagnosed with moderate to severe dementia * Unstable patient condition as judged by investigator (e.g., hypertension, diabetes, and systematic disease)