title: Prevalence and characterization of cardiac involvement in Hunter syndrome.
abstract: OBJECTIVE
  To assess the prevalence of cardiovascular signs and symptoms in a large group of patients with Hunter syndrome, an X-linked metabolic disorder caused by a deficiency of the lysosomal enzyme iduronate-2-sulfatase.
  
  
  METHODS
  The Hunter Outcome Survey was established to characterize the natural history of Hunter syndrome and to assess the response to enzyme replacement therapy. Echocardiographic and electrocardiographic examination results were available for 102 patients who were enzyme replacement therapy-naïve in the Hunter Outcome Survey (median age at examination, approximately 8 years) as of Jan 23, 2009.
  
  
  RESULTS
  The most common cardiovascular finding was valve disease, which was present in 63% of patients. Left ventricular hypertrophy (defined as left ventricular mass indexed to height(2.7) ≥50 g/m(2.7)) was found in 48% of patients <18 years old. Elevated blood pressure (defined as a Z score ≥2 for systolic blood pressure or diastolic blood pressure) was present in 25% of patients <18 years old. Other findings included abnormal heart frequency (7%), arrhythmia (5%), and congestive heart failure (6%).
  
  
  CONCLUSIONS
  Treating physicians should be aware of the early emergence of cardiovascular manifestations in patients with Hunter syndrome so that appropriate treatment can be initiated.
authors.affiliation: Division of Cardiology, University Children's Hospital, Mainz, Germany. kampmann@mail.uni-mainz.de
authors.forename: Christoph
authors.initials: C
authors.lastname: Kampmann
authors.forename: Michael
authors.initials: M
authors.lastname: Beck
authors.forename: Isabelle
authors.initials: I
authors.lastname: Morin
authors.forename: James P
authors.initials: JP
authors.lastname: Loehr
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography; D004562:Electrocardiography; D005500:Follow-Up Studies; D005858:Germany / Q000453:epidemiology; D006331:Heart Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007066:Iduronate Sulfatase / Q000097:blood; D008297:Male; D016532:Mucopolysaccharidosis II / Q000150:complications* / Q000201:enzymology / Q000453:epidemiology; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D007066:Iduronate Sulfatase