Syndecan-1 Predicts Outcome in Patients with ST-Segment Elevation Infarction Independent from Infarct-related Myocardial Injury

Syndecan-1 (sdc1) is a surface protein part of the endothelial glycocalyx (eGC). Soluble sdc1 is derived from shedding and indicates damaged eGC. We assessed the predictive value of plasma sdc1 concentrations for future cardiovascular events in acute reperfused ST-segment elevation myocardial infarction (STEMI) patients. A total of 206 patients admitted for STEMI were included in this study (29% female; age 65 ± 12 years) and followed-up for six months. Plasma samples were obtained post-intervention and analyzed for sdc1 by Enzyme-linked Immunosorbent Assay (ELISA). Primary outcome was six-month-mortality. Sdc1 did not correlate with biomarkers such as creatine kinase (CK) (r = 0.11; p = 0.01) or troponin (r = -0.12; p = 0.09), nor with infarct size (r = -0.04; p = 0.67) and myocardial salvage index (r = 0.11; p = 0.17). Sdc-1 was associated with mortality (changes per 100 ng/mL sdc-1 concentration; HR 1.08 95% 1.03-1.12; p = 0.001). An optimal cut-off was calculated at >120 ng/mL. After correction for known risk factors sdc1 >120 ng/mL was independently associated with mortality after 6 months. In our study, sdc1 is independently associated with six-month-mortality after STEMI. Combining clinical evaluation and different biomarkers assessing both infarct-related myocardial injury and systemic stress response might improve the accuracy of predicting clinical prognosis in STEMI patients.