Brachial Artery Endothelial-dependent Flow-mediated Dilation Identifies Early-stage Endothelial Dysfunction in Systemic Sclerosis and Correlates with Nailfold Microvascular Impairment

Objective. To assess possible correlations between endothelial-dependent flow-mediated dilation (FMD) of the brachial artery and nailfold videocapillaroscopy (NVC) in patients with systemic sclerosis (SSc). Evidence has shown that vascular impairment in SSc may be a sign of endothelial dysfunction involving both microvascular and macrovascular systems, although the pathological mechanisms of the dysfunction are poorly understood. Methods. Forty-three consecutive patients (mean age 51 +/- 11 yrs) with SSc were studied. Thirty patients had limited cutaneous SSc, 13 had diffuse cutaneous SSc. Twenty-seven healthy subjects (mean age 48 8 yrs) were recruited as controls. Ultrasound assessment of FMD was performed on all subjects in order to evaluate macrovascular function. Patients were divided into 3 patterns of microvascular damage on the basis of NVC (early, active, and late), and the microangiopathy evolution score was calculated, as reported elsewhere. esults. FMD was significantly reduced in patients with SSc compared to healthy subjects [median 8.0% (3.0%-9.0%) vs 15.0% (12.0%-16.0%), respectively; p<0.0001]. Patients with an early pattern of microangiopathy showed reduced FMD values compared to controls (p = 0.0001). FMD was significantly reduced in patients with SSc who had the late NVC pattern of microangiopathy compared to active and early patterns (p = 0.003 and p = 0.001, respectively). FMD was inversely correlated with the microvascular damage rate in patients with SSc (p<0.0001). Conclusion. We demonstrated the simultaneous presence of macrovascular and microvascular impairment in patients with SSc, which was already present in the early phase of the vascular disease. (First Release May 1 2010; J Rheumatol 2010;37:1168-73; doi:10.3899/jrheum.091116)