Endothelial Biomarkers of Systemic Sclerosis-associated Pulmonary Hypertension

Systemic sclerosis (SSc, AKA scleroderma) is an autoimmune condition characterized by
endothelial damage and progressive fibrosis of the skin and internal organs. One of the
leading causes of morbidity and mortality in patients with SSc is pulmonary hypertension
(PH), which is estimated to occur in up to 31% of high risk SSc patients. Early detection of
patients with SSc-PH may lead to improved outcomes and although there have been concerted
efforts to accurately screen for SSc-PH, these patients continue to present with advanced
disease and suffer from poor survival. Therefore, better methods to screen for patients with
PH and, perhaps more importantly, to screen for those at risk for PH development are
desperately needed. Since PH and SSc are disorders originating from the endothelium,
biomarkers that reflect endothelial damage are very promising tools to identify early
disease. Such potential biomarkers include endothelial microparticles, asymmetric
dimethylarginine (ADMA), pentraxin-3, and soluble endoglin. No previous study has used a
combination of these biomarkers to detect the presence of PH in patients with SSc, or studied
the novel concept of exercise-induced changes in biomarker levels. The investigators will
collect the above listed endothelial biomarkers before and after exercise, and combine these
levels with exercise echocardiogram findings, and routine clinical information to derive a
composite detection score for the early identification of systemic sclerosis-associated PH.