Association of improvement of brachial artery flow-mediated vasodilation with cardiovascular events.

The aim of this pilot study was to test the prognostic value of serial measurements of peripheral endothelial function, assessed by brachial artery flow-mediated dilation (FMD), in patients with angiographically proven coronary artery disease. In 68 patients, FMD was measured on the day after coronary angiography and again after a mean of 14 +/- 12 months. Patients were divided into two groups: absolute improvement in FMD > or = 3% (FMD-improver = FMD-i) and < 3% (FMD-non-improver = FMD-ni). After a mean follow-up of 44 +/- 12 months, cardiovascular events were recorded. Baseline characteristics were similar between groups, except the number of risk factors which was smaller in FMD-i (1.6 +/- 0.7 vs 2.1 +/- 0.9, p < 0.02). Cardiovascular events were more frequent in FMD-ni (9 vs 1 event; p < 0.05). In Kaplan-Meier analysis, a trend towards a better outcome in patients with improved FMD was found using the log-rank test (p = 0.08). The single baseline FMD showed no relationship with late cardiovascular events. Thus, 'delta-FMD' may be more closely related to prognosis than a single FMD measurement.