title: Phosphorus-31 two-dimensional chemical shift imaging in the myocardium of patients with late onset of Friedreich ataxia.
abstract: OBJECTIVE
  Friedreich ataxia (FRDA) is characterized by GAA expansions in the intron 1 of the frataxin gene correlating with disease onset and progression as well as cardiac affection. Accordingly, FRDA patients with early disease onset show a clear impairment of mitochondrial function in the myocardium. The purpose of this study was to investigate cardiac function and high-energy phosphate metabolism in FRDA patients with late disease onset.
  
  
  METHODS
  Using a 1.5 T magnetic resonance scanner, cardiac phosphorus-31 two-dimensional chemical shift imaging was performed in ten patients (seven male, three female) with a late onset of FRDA and in 35 healthy, male controls. Ejection faction (EF) and interventricular septum thickness (IST) were determined by echocardiography.
  
  
  RESULTS
  The differences in left ventricular phosphocreatine (PCr) to beta-adenosine triphosphate (beta-ATP) ratios between both groups were not significant. FRDA patients had increased ISTs (10.8+/-1.6 vs. 9.7+/-0.9 mm; p=0.048), which correlated significantly with the left ventricular PCr to beta-ATP ratios (r= -0.644; p=0.04), and decreased EFs (52.24+/-7.72% vs. 64.09+/-4.25%; p=0.001) compared to normal controls.
  
  
  CONCLUSIONS
  In contrast to FRDA patients with early disease onset, our patients collective exhibited a normal, probably compensated cardiac mitochondrial function, whereby IST and EF were mildly altered.
authors.affiliation: Department of Radiology I, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Wolf
authors.forename: Sylvia
authors.initials: S
authors.lastname: Boesch
authors.forename: Bernhard
authors.initials: B
authors.lastname: Metzler
authors.forename: Helga
authors.initials: H
authors.lastname: Weirich-Schwaiger
authors.forename: Thomas
authors.initials: T
authors.lastname: Trieb
authors.forename: Michael F H
authors.initials: MF
authors.lastname: Schocke
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D017668:Age of Onset; D003710:Demography; D005260:Female; D005621:Friedreich Ataxia / Q000453:epidemiology / Q000378:metabolism*; D006352:Heart Ventricles / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009206:Myocardium / Q000473:pathology*; D010725:Phosphocreatine / Q000378:metabolism; D010759:Phosphorus Isotopes
chemical_list: D010759:Phosphorus Isotopes; D010725:Phosphocreatine; D000255:Adenosine Triphosphate