title: Mucopolysaccharidosis: cardiologic features and effects of enzyme-replacement therapy in 24 children with MPS I, II and VI.
abstract: We determined the cardiologic features of children with MPS I, II and VI, and evaluated the effect of enzyme-replacement therapy (ERT) on cardiac disease. Twenty-four children aged 1-18 years with MPS I, II or VI were prospectively evaluated with echocardiogram and electrocardiogram from the start of enzyme-replacement therapy up to 6 years of treatment. At start of therapy, 66% had abnormal cardiac geometric features. Left-ventricular mass index (LVMI) was increased in half of the patients, due mainly to concentric hypertrophy in MPS I and II and to eccentric hypertrophy in MPS VI. Regurgitation was most severe in a subgroup of young MPS VI patients (<5 years) at the mitral valve. At baseline, all patients had abnormal valves. The ECG showed no clear rhythm or conduction abnormalities; neither, in most patients, did it reflect the hypertrophy. After ERT, the LVMI Z-score normalized in 70% of the patients who had a Z-score > 2. LVMI Z-scores decreased significantly in patients with MPS I and MPS II (p = 0.04 and p = 0.032). Despite ERT, valve regurgitation increased in 60% of the patients. We conclude that all our MPS patients have cardiac abnormalities. The most severe cardiac disease was observed in a subgroup of young MPS VI patients. While ERT had an effect on LVMI and IVSd, it apparently had little or none on valve regurgitation.
authors.affiliation: Department of Pediatrics, division of Metabolic Diseases and Genetics, Center for Lysosomal and Metabolic Diseases, Erasmus MC University Medical Center/Sophia's Children's Hospital, Dr. Molewaterplein 60, Rotterdam, The Netherlands.
authors.forename: Marion M M G
authors.initials: MM
authors.lastname: Brands
authors.forename: Ingrid M
authors.initials: IM
authors.lastname: Frohn-Mulder
authors.forename: Marloes L C
authors.initials: ML
authors.lastname: Hagemans
authors.forename: Wim C J
authors.initials: WC
authors.lastname: Hop
authors.forename: Esmee
authors.initials: E
authors.lastname: Oussoren
authors.forename: Wim A
authors.initials: WA
authors.lastname: Helbing
authors.forename: Ans T
authors.initials: AT
authors.lastname: van der Ploeg
mesh_terms: D000293:Adolescent; D002309:Cardiology / Q000379:methods; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography / Q000379:methods; D004562:Electrocardiography / Q000379:methods; D056947:Enzyme Replacement Therapy / Q000379:methods*; D005260:Female; D006331:Heart Diseases / Q000503:physiopathology*; D006801:Humans; D007223:Infant; D008297:Male; D009083:Mucopolysaccharidoses / Q000188:drug therapy* / Q000503:physiopathology*; D011446:Prospective Studies