Non-invasive assessment of endothelial activity in patients with coronary heart disease and cardiovascular risk factors.
BACKGROUND
The aim of this study was first to compare the widely used flow mediated dilation ( FMD ) method with the iontophoretically induced acetylcholine vasodilation (IAV ) procedure. The ultimate goal was to examine the endothelial activity ( EA ) in patients with various cardiovascular risk factors compared with control subjects.


METHODS
In the upper extremities of 27 subjects, comparisons of EA by FMD and IAV measured with laser Doppler flux method (LDF) were conducted. IAV-EA was then measured using LDF in an additional 93 subjects with various cardiovascular ( CVD ) risk factors and/or a diagnosis of coronary heart disease (CHD).


RESULTS
The mean age of the subjects was 56.2 years and 54% were male. There was a robust and significant correlation between FMD vs IAV endothelial activity (r = 0.87, p = 0.025). After adjustment for age, there were significant differences in LDF-measured, acetylcholine-induced EA by diagnosis of CHD (p = 0.02), hyperlipidemia (p = 0.03) and diabetes (p < 0.01), as well as by sex (p < 0.01). The difference by hypertension status was of borderline significance (p = 0.07). LDF EA was higher in non-smokers compared to smokers but this difference was not statistically significant (p = 0.3). After adjustment for age and gender, a 10-unit increase in LDF-measured EA was associated with a 12% lower odds for a diagnosis of CHD (p = 0.07).


CONCLUSIONS
Measurement of IAV-EA by LDF is a simple, noninvasive methodology which is highly correlated with post-occlusive FMD EA and is also significantly associated with a diagnosis of CHD.
Fronek
A
A
Department of Surgery, University of California San Diego, La Jolla, CA 92093-0630, USA. afronek@ucsd.edu
Allison
M
M
D000109:Acetylcholine / Q000008:administration & dosage; D003324:Coronary Artery Disease / Q000175:diagnosis*; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D014665:Vasodilator Agents
D014665:Vasodilator Agents; D000109:Acetylcholine