Colombian study to assess the use of noninvasive determination of endothelium-mediated vasodilatation (CANDEV). Normal values and factors associated

The endothelium plays a critical role in vascular homeostasis. Recently, a noninvasive method has been developed to assess flow mediated vasodilatatio n of the brachial artery (FMD). This test is remarkably stable overtime but no clear set of normal values has been developed. The purposes of our stud y were to evaluate the accuracy and reproducibility and to identify a set o f normal values of FMD. We included 253 normotensive healthy volunteers fro m three Colombian cities (mean age: 38.2 years; 33% were women). All subjec ts underwent ultrasound evaluation of endothelial and smooth muscle functio n. Flow mediated vessel diameter change was measured by two independent obs ervers. The interobserver Lin's concordance correlation coefficient was 0.8 8% (95% CI:0.82, 0.94) and there was no evidence of systematic difference b etween the two measurements (mean difference of -0.30% with limits of agree ment of -4.48 to 3.87). Mean %FMD was 11.98% (95% CI: 11.36, 12.61), 13.32% (95% CI: 12.39, 14.25) in women and 11.32% (95% CI: 10.52, 12.13) in men. Subjects with no cardiovascular risk factors had a mean %FMD of 13.74 % (95 % CI: 13.14, 14.35), in contrast to a mean of only 7.40% (95% CI:4.33, 9.91 ) in those with at least one risk factor. A %FMD cut point of 10.4 had a se nsitivity of 71.2% and an specificity of 77.2% to identify subjects with at least one cardiovascular risk factor. Using this cut point, endothelial dy sfunction was 3.13 times more frequent in subjects with than in subjects wi thout cardiovascular risk factors (95% Cl: 2.30, 4.25). In addition, obesit y, smoking and hypercholesterolemia were the modifiable risk factors with l argest independent significant reduction effects on %FMD. FMD measurements can be made with high accuracy and precision, and a cut point of 10.4% is u seful to discriminate between subjects with and without cardiovascular risk factors, and can be recommended as a screening test for the detection of p atients at risk of CVD.