The value of endothelium dependent vasodilatation in diagnosing coronary artery disease and its comparison with the results of routine diagnostic tests.
OBJECTIVE
To determine the predictive value of flow-mediated vasodilation (FMD) compared with angina pectoris, exercise electrocardiography, and myocardial perfusion imaging (MPI).


METHODS
This study was carried out in Shahid Madani Heart Center, Tabriz, Iran from April 2004 to September 2006. A total of 92 patients with chest pain syndrome were enrolled in this study. Using high resolution ultrasound system endothelial function was evaluated, and the result of the flow-mediated dilation (FMD%) was defined as the percent change in the internal diameter of the brachial artery during reactive hyperemia related to baseline.


RESULTS
Coronary artery disease (CAD) was documented in 77 (83.7%) patients. The percentage of FMD was lower in patients with CAD compared with those +/- 4.61, p=0.001). In comparison with typical anginal chest pain (sensitivity 46.7%, specificity 80%), exercise stress test (sensitivity 75%, specificity 60%), and MPI (sensitivity 96.5, specificity 55.6%) the receiver operator characteristic curve showed the percentage FMD optimal cut-off value as </=7.41 with a sensitivity of 87.0%, specificity of 66.7%, negative predictive value of 93.0%, and positive predictive value of 50%.


CONCLUSIONS
In patients with chest pain syndrome, the FMD is a sensitive indicator of CAD with moderate specificity that is unable to predict accurately the extent and severity of it.
Ghaffari
Samad
S
Department of Cardiology, Cardiovascular Research Center of Tabriz University of Medical Science, Tabriz, Iran. ghafaris@gmail.com
Toufan
Mehrnoosh
M
D000328:Adult; D000368:Aged; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D014463:Ultrasonography; D014664:Vasodilation / Q000502:physiology*