title: Diffuse left ventricular interstitial fibrosis is associated with sub-clinical myocardial dysfunction in Alström Syndrome: an observational study.
abstract: BACKGROUND
  Alström syndrome is a rare inherited ciliopathy with progressive multisystem involvement. Dilated cardiomyopathy is common in infancy and recurs or presents de novo in adults with high rates of premature cardiovascular death. Although Alström syndrome is characterised by fibrosis in solid organs such as the liver, the pathogenesis of related cardiomyopathy are not clear. To date it is not known whether diffuse interstitial myocardial fibrosis is present before the onset of heart failure symptoms or changes in conventional parameters of left ventricular function.
  
  
  METHODS
  In this observational study, 26 patients with Alström syndrome (mean age 27 ± 9 years, 65 % male, 24 h ABPM 130 ± 14 / 77 ± 9 mmHg) without symptomatic cardiovascular disease were recruited from a single centre and compared to matched healthy controls. All subjects underwent cardiac MRI (1.5 T) to assess ventricular function, diffuse interstitial myocardial fibrosis by measurement of extracellular volume on T1-mapping (MOLLI) and coarse replacement fibrosis using standard late gadolinium enhancement imaging.
  
  
  RESULTS
  Global extracellular volume was increased in Alström syndrome with wider variation compared to controls (0.30 ± 0.05 vs. 0.25 ± 0.01, p < 0.05). Left ventricular long axis function and global longitudinal strain were impaired in Alström syndrome without change in ejection fraction, ventricular size or atrial stress (NT-proBNP) (p < 0.05). Global extracellular volume was associated with reduced peak systolic longitudinal strain (r = -0.73, p < 0.01) and strain rate (r = -0.57, p < 0.01), increased QTc interval (r = 0.49, p < 0.05) and serum triglycerides (r = 0.66, p < 0.01). Nine (35 %) patients had diffuse mid-wall late gadolinium enhancement in a non-coronary artery distribution.
  
  
  CONCLUSIONS
  Diffuse interstitial myocardial fibrosis is common in Alström syndrome and is associated with impaired left ventricular systolic function. Serial studies are required to determine whether global extracellular volume may be an independent imaging biomarker of vulnerability to dilated cardiomyopathy and heart failure.
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK. n.c.edwards@bham.ac.uk.|Department of Cardiology, Queen Elizabeth Hospital, Birmingham, UK. n.c.edwards@bham.ac.uk.
authors.forename: Nicola C
authors.initials: NC
authors.lastname: Edwards
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK.|Department of Cardiology, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: William E
authors.initials: WE
authors.lastname: Moody
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK.
authors.forename: Mengshi
authors.initials: M
authors.lastname: Yuan
authors.affiliation: Department of Pathology, Queen Elizabeth Hospital, Birmingham, England.
authors.forename: Adrian T
authors.initials: AT
authors.lastname: Warfield
authors.affiliation: Department of Biochemistry, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Cramb
authors.affiliation: Department of Diabetes, Torbay Hospital, Torbay, UK.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Paisey
authors.affiliation: Department of Endocrinology, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Tarekegn
authors.initials: T
authors.lastname: Geberhiwot
authors.affiliation: School of Clinical and Experimental Medicine, University of Birmingham, Birmingham, UK.|Department of Cardiology, Queen Elizabeth Hospital, Birmingham, UK.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Steeds
mesh_terms: D000293:Adolescent; D000328:Adult; D056769:Alstrom Syndrome / Q000473:pathology* / Q000503:physiopathology; D009202:Cardiomyopathies / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006352:Heart Ventricles / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D016277:Ventricular Function, Left / Q000502:physiology; D055815:Young Adult