Systemic sclerosis induces pronounced peripheral vascular dysfunction characterized by blunted peripheral...

Area of Science:

• Vascular Medicine
• Rheumatology
• Diagnostic Ultrasound

Background:

• Systemic sclerosis (SSc) is associated with vasculopathy, leading to digital ulcers (DU) and pulmonary arterial hypertension (PAH).
• Early identification of SSc patients at risk for DU or PAH is crucial for timely intervention.

Purpose of the Study:

• To investigate the utility of bedside brachial artery flow-mediated dilation (FMD) testing using duplex ultrasound in identifying SSc patients at risk for DU or PAH.

Main Methods:

• Compared 38 SSc patients with 52 healthy controls using duplex ultrasound to assess peripheral hemodynamics, arterial structure, and endothelial function.
• Measured brachial artery vascular reactivity, shear rate, and FMD after inducing 5-minute forearm ischemia.

Main Results:

• SSc patients exhibited smaller brachial artery diameters, reduced reactive hyperemia, lower peak shear rate, and significantly impaired FMD compared to controls.
• SSc patients with DU had lower brachial artery FMD than those without DU.
• Lower FMD tertiles (<5.40%) were associated with a 40-50% chance of DU, while the highest tertile (>5.40%) had <15% chance.
• No significant differences in FMD were observed between SSc patients with and without PAH.

Conclusions:

• SSc patients demonstrate impaired peripheral vascular reactivity and endothelial function compared to healthy individuals.
• FMD testing is a valuable clinical tool for identifying SSc patients at increased risk for developing digital ulcers.
• FMD testing may not be suitable for identifying SSc patients at risk for PAH.