Markers of Endothelial Injury in Extracorporeal Membrane Oxygenation: A New Risk Assessment Method

Extracorporeal membrane oxygenation (ECMO) has become more widely used in recent years. However, ECMO remains a resource-intensive modality, and identifying patients most likely to benefit from it can be a complex task. Few methods exist to help risk stratify potential ECMO patients. Syndecan-1 (SDC-1) and soluble thrombomodulin (sTM) are markers of endothelial dysfunction and are used as a sign of disease severity in various forms of trauma. Our study aims to evaluate the association between precannulation levels of SDC-1 and sTM with mortality, current scoring systems, and their ability to predict mortality on ECMO.

Patients initiated on venoarterial ECMO were retrospectively analyzed. Clinical data were collected, and precannulation Acute Physiology and Chronic Health Evaluation scores were calculated. Blood samples from precannulation collection were assayed for SDC-1 and sTM by enzyme linked immunosorbent assay. The primary outcome was mortality on ECMO.

Thirty-four patients were included in the analysis. Most were male (76.5%), with a median age of 61.5 y and body mass index of 28.2. Overall mortality was 61.7%. sTM was significantly higher in patients who died on venoarterial ECMO compared to those who lived. Pre-SDC-1 level of ≥951 ng/mL is marginally predictive of a higher mortality risk (area under the receiver operating characteristic curve 0.70; P = 0.070). Pre-sTM levels of ≥5348 pg/mL predicted mortality (area under the receiver operating characteristic curve 0.89; P = 0.003).

SDC-1 and sTM are associated with a higher mortality risk in patients on ECMO. These biomarkers may be a valuable addition to current scoring systems. Furthermore, more work should focus on characterizing the effects of cardiogenic shock on the endothelium.