title: Higher CHADS2 score is associated with impaired coronary flow reserve: A study using phase contrast cine magnetic resonance imaging.
abstract: BACKGROUND
  The presence of coronary microvascular dysfunction (CMD) is an important prognostic marker for coronary artery disease (CAD) patients. The purpose of this study was to investigate whether the CHADS2 score is associated with CMD evaluated by magnetic resonance imaging (MRI).
  
  
  METHODS
  One hundred forty three patients with known or suspected CAD (mean age 70.3±9.5years) were enrolled. All patients did not have any significant coronary stenosis on X-ray coronary angiography (CAG) at the time of MRI acquisition. By using a 1.5T MRI scanner, breath-hold phase contrast cine MRI images of coronary sinus (CS) were obtained to assess the blood flow of CS both at rest and during adenosine triphosphate (ATP) infusion. Coronary flow reserve (CFR) was calculated as CS blood flow during ATP infusion divided by CS blood flow at rest. CMD was defined as CFR<2.5 according to a previous study. Patients were allocated to four groups based on the CHADS2 score (group1: CHADS2 score=0, group2: CHADS2 score=1; group3: CHADS2 score=2, and group4: CHADS2 score≥3).
  
  
  RESULTS
  Mean CFR was 2.81±0.95 (77.6±32.7mL/min at rest; 208.2±86.5mL/min during ATP infusion, p<0.001). Patients with higher CHAD2 score had lower CFR. In the multiple logistic regression analysis, CHADS2 score was independently associated with CFR (odds ratio=0.61, 95% confidence interval: 0.37-0.99, p=0.049).
  
  
  CONCLUSIONS
  Higher CHADS2 score was significantly associated with lower CFR evaluated by phase contrast cine MRI.
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Hidekuni
authors.initials: H
authors.lastname: Kirigaya
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan. Electronic address: shingo.m12226@gmail.com.
authors.forename: Shingo
authors.initials: S
authors.lastname: Kato
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Daiki
authors.initials: D
authors.lastname: Gyotoku
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Yamada
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Iinuma
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Kusakawa
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Iguchi
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Miki
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nakachi
authors.affiliation: Department of Cardiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Fukui
authors.affiliation: Department of Radiology, Kanagawa Cardiovascular and Respiratory Center, Japan.
authors.forename: Tae
authors.initials: T
authors.lastname: Iwasawa
authors.affiliation: Division of Cardiology, Yokohama City University Medical Center, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kimura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D017023:Coronary Angiography / Q000379:methods; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index
keywords: CHADS2 score; Coronary flow reserve; Magnetic resonance imaging