title: Changes of central retinal artery blood flow and endothelial function in patients with coronary artery disease.
abstract: OBJECTIVE
  In patients with coronary artery disease (CAD), endothelial function is usually impaired, but the parameters of central retinal artery (CRA) blood flow have not yet been investigated. We designed the study to test the parameters of CRA blood flow and brachial artery flow-mediated dilation (FMD), accompanied by an aim of establishing whether a link may exist between the parameters of CRA blood flow and endothelial function.
  
  
  METHODS
  Twenty-five subjects were diagnosed as CAD by coronary angiography, and 30 control subjects had normal coronary artery. CRA blood flow and brachial artery FMD were measured noninvasively using high-resolution ultrasound.
  
  
  RESULTS
  In patients with CAD, peak systolic velocity (PSV), end diastolic velocity (EDV), and time velocity integral (TVI) of CRA blood flow were significantly lower (8.75 +/- 2.09 vs. 10.15 +/- 2.16 cm/s, 2.55 +/- 0.73 vs. 3.81 +/- 0.90 cm/s, 5.01 +/- 1.32 vs. 6.27 +/- 1.28 cm/s, respectively, p = 0.019, p < 0.01, p < 0.01), conversely, pulsatility index (PI) and resistance index (RI) were significantly higher (1.28 +/- 0.22 vs. 1.01 +/- 0.20, 0.71 +/- 0.06 vs. 0.62 +/- 0.07, respectively, p < 0.01) when compared with those in normal controls. Meanwhile, brachial artery FMD was decreased in CAD patients (3.91 +/- 1.65 vs. 8.78 +/- 2.92, p < 0.01). After controlling for age, gender, heart rate, and blood pressure, the PSV, EDV, TVI, PI or RI in CRA blood flow were associated with the brachial artery FMD (r = 0.182, 0.372, 0.245, -0.320, or -0.367, respectively, p = 0.205, p = 0.008, p = 0.087, p = 0.023, or p = 0.009).
  
  
  CONCLUSIONS
  This study indicates that CRA blood flow is impaired in patients with CAD, and this may partly relate to endothelial dysfunction. Thus, endothelial function is likely to play an important role in the CRA microcirculation.
authors: Department of Cardiology, Second Hospital of Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang 050017, People's Republic of China. caswu1972@hotmail.com
authors: Yuzhou
authors: Y
authors: Wu
authors: Shuqin
authors: S
authors: Li
authors: Xiuguang
authors: X
authors: Zu
authors: Jun
authors: J
authors: Du
authors: Fengfei
authors: F
authors: Wang
mesh_terms: D001783:Blood Flow Velocity; D001916:Brachial Artery / Q000503:physiopathology*; D003324:Coronary Artery Disease / Q000503:physiopathology*; D003971:Diastole; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011673:Pulsatile Flow; D012039:Regional Blood Flow; D012161:Retinal Artery / Q000503:physiopathology*; D013599:Systole; D014655:Vascular Resistance; D014664:Vasodilation