title: The heart in Friedreich ataxia: definition of cardiomyopathy, disease severity, and correlation with neurological symptoms.
abstract: BACKGROUND
  This cross-sectional study provides a practical approach for the clinical assessment of Friedreich ataxia (FA) cardiomyopathy (FA-CM).
  
  
  RESULTS
  A comprehensive cardiac assessment, including standard echocardiography, color Doppler myocardial imaging, cardiac magnetic resonance imaging, ECG, and exercise stress testing, was performed in 205 FA patients. To assess myocardial hypertrophy in FA-CM, the end-diastolic interventricular septal wall thickness (IVSTd) was found to be the best echocardiographic parameter compared with cardiac magnetic resonance imaging-determined left ventricular mass. With the use of this parameter, 4 groups of patients with FA-CM could be defined. Patients with normal values for IVSTd (31.7%) were classified as having no FA-CM. Patients with an IVSTd exceeding the predicted normal IVSTd were classified as having mild FA-CM (40%) if IVSTd exceeded the normal value by <18% or as having intermediate FA-CM (16.1%) if IVSTd exceeded the normal value by ≥18%. Patients with ejection fraction <50% were classified as having severe FA-CM (12.2%). In addition to increased myocardial mass, severe FA-CM was further characterized by dilatation of the left ventricle, reduced systolic strain rate of the posterior wall, and ECG abnormalities. Regional myocardial function correlated negatively with FA-CM groups. Younger patients had a tendency for more advanced FA-CM. Importantly, no clear correlation was found between FA-CM groups and neurological function.
  
  
  CONCLUSIONS
  We provide and describe a readily applicable clinical grouping of the cardiomyopathy associated with FA based on echocardiographic IVSTd and ejection fraction data. Because no distinct interrelations between FA-CM and neurological status could be determined, regular follow-up of potential cardiac involvement in FA patients is essential in clinical practice.
authors.affiliation: Medizinische Klinik und Poliklinik I, Universitätsklinik Würzburg, Oberdürrbacherstrasse 6, Würzburg, Germany. weidemann_f@medizin.uni-wuerzburg.de
authors.forename: Frank
authors.initials: F
authors.lastname: Weidemann
authors.forename: Christian
authors.initials: C
authors.lastname: Rummey
authors.forename: Bart
authors.initials: B
authors.lastname: Bijnens
authors.forename: Stefan
authors.initials: S
authors.lastname: Störk
authors.forename: Ruta
authors.initials: R
authors.lastname: Jasaityte
authors.forename: Jan
authors.initials: J
authors.lastname: Dhooge
authors.forename: Aigul
authors.initials: A
authors.lastname: Baltabaeva
authors.forename: George
authors.initials: G
authors.lastname: Sutherland
authors.forename: Jörg B
authors.initials: JB
authors.lastname: Schulz
authors.forename: Thomas
authors.initials: T
authors.lastname: Meier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005621:Friedreich Ataxia / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D006321:Heart / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D012720:Severity of Illness Index; D055815:Young Adult