Background and purpose: Brachial arterial flow-mediated dilation (FMD) reflects endothelium-dependent vasodilation function. FMD is diminished in patients with endothelial dysfunction (ED). Our aim was to investigate the relationship between FMD and outcome for patients with acute ischemic stroke.
Methods: We measured FMD in 120 consecutive patients (58.3% male, median age 73 years) with acute ischemic stroke within the first 48 h of onset of the stroke, using high-resolution ultrasonography. FMD was calculated as the relationship between basal diameter of the brachial artery before (d(1)) and after (d(2)) transient vascular occlusion (300 mmHg for 4 min) was measured using a sphygmomanometer (FMD = d(2) - d(1)/d(1) x 100). Poor outcome was defined as modified Rankin Scale at 3 months >2. FMD was categorized according to ROC analysis and we defined ED as FMD < or = 4.5%.
Results: Thirty-three patients (27.5%) had ED. Median % FMD was 9.12 (7.48). FMD negatively correlated to stroke severity (P = 0.045). Median FMD was significantly lower [4.5 (2.3, 10.3) vs. 9.4 (5.6, 15.1), P = 0.003] for patients with poor outcome (n = 38). The adjusted odds ratio of poor outcome for FMD < or = 4.5% was 3.03 (95% CI, 1.09-27.3).
Conclusions: Impaired FMD in patients with acute ischemic stroke is associated with poor outcome.