Temporal heterogeneity of endothelium-dependent and -independent dilatation of brachial artery in patients with coronary artery disease

摘要: Background: Endothelial function is routinely assessed with high frequency ultrasound of the brachial artery. Fixed time points (1′ post-occlusion and 3′ post-nitrate) are commonly used to assess dynamic changes in artery diameter. The underlying assumption lack variability temporal response both endothelium-dependent -independent stimuli. Objective: To evaluate course (flow-mediated) endothelium-independent (nitrate-induced) vasodilation patients coronary disease (CAD) using resolution (10 MHz) ultrasound. Methods: Thirty-seven angiographically CAD were prospectively enrolled study. End-diastolic, two-dimensional, long axis ultrasonographic images digitally stored on-line every 10 s, from baseline up 4′ during flow-mediated 7′ 300 μg sublingual nitrate-induced Results: mean percent maximal dilation (FMD) measured at 60 s was lower than peak FMD (4.8 ± 4.1 vs. 6.6 5.2%; p < 0.01). By only eight (35%) reached their maximum response. reach 87 33 s. for nitrate 291 73 higher that 3 min (12.2 6.7 5.4 4.5%; 0.001). 190 four (11%) Conclusion: measurement evaluation may not be adequate detect responses individual CAD.