title: Coronary flow reserve is impaired in patients with nonalcoholic fatty liver disease: association with liver fibrosis.
abstract: BACKGROUND
  Nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of cardiovascular disease. Coronary flow reserve (CFR) is widely used to examine the integrity of coronary microvascular circulation. We evaluated the prevalence of impaired CFR in patients with biopsy-proven NAFLD. We also investigated the independent clinical, biochemical, and liver histology predictors of CFR in the setting of NAFLD.
  
  
  METHODS
  Fifty-nine consecutive patients with NAFLD and 77 age- and gender-matched controls were evaluated. CFR recordings were performed by transthoracic Doppler harmonic echocardiography. CFR>or=2.0 was considered normal.
  
  
  RESULTS
  CFR was significantly lower in patients with NAFLD than in controls (2.11+/-0.45 vs. 2.52+/-0.62, P<0.001). An impaired CFR (i.e. <2) was found in 25 NAFLD patients (42.4%) whereas all controls had normal CFR values (P<0.001). A stepwise linear regression analysis in NAFLD patients identified liver fibrosis scores as the only independent predictor of CFR values (beta=-0.60; t=-2.44, P=0.021).
  
  
  CONCLUSIONS
  Our findings indicate that in patients with biopsy-proven NAFLD: (a) an abnormal CFR is found in approximately 42.4% of cases, and (b) liver fibrosis scores are an independent predictor of depressed CFR.
authors.affiliation: Department of Gastroenterology, Marmara University School of Medicine, Tophanelioglu Cad. No: 13/15 Altunizade, 34662 Istanbul, Turkey. yusufyilmaz@uludag.edu.tr
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Yilmaz
authors.forename: Ramazan
authors.initials: R
authors.lastname: Kurt
authors.forename: Oya
authors.initials: O
authors.lastname: Yonal
authors.forename: Nihat
authors.initials: N
authors.lastname: Polat
authors.forename: Cigdem Ataizi
authors.initials: CA
authors.lastname: Celikel
authors.forename: Ahmet
authors.initials: A
authors.lastname: Gurdal
authors.forename: Huseyin
authors.initials: H
authors.lastname: Oflaz
authors.forename: Osman
authors.initials: O
authors.lastname: Ozdogan
authors.forename: Nese
authors.initials: N
authors.lastname: Imeryuz
authors.forename: Cem
authors.initials: C
authors.lastname: Kalayci
authors.forename: Erol
authors.initials: E
authors.lastname: Avsar
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D003326:Coronary Circulation; D005234:Fatty Liver / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008833:Microcirculation; D008875:Middle Aged