Abstract 5848: Serum SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily a-like (SMARCAL)-1 Concentrations Predict Primary Graft Dysfunction in Cardiac Transplant Recipients
Primary graft dysfunction (PGD) is a life-threatening complication in cardiac transplantation. A sensitive, specific, easily and quickly measurable serum predictor could facilitate PGD prevention and treatment. SMARCAL1 is a matrix-associated regulator of chromatin with helicase and ATPase activities, and its serum concentrations were significantly increased in a targeted protein array in cardiac transplant recipients with PGD. Therefore, this prospective study analyzed SMARCAL1 serum concentrations by ELISA in 222 consecutive heart donors before and after aortic cross-clamping (ACC) and in recipients at 10, 30 and 60 minutes following reperfusion. Demographic and hemodynamic parameters of donors and recipients as well as transplant procedure characteristics were documented. PGD (n= 46) was defined as ventricular dilation and hypocontractility associated with systolic blood pressure < 90 mm Hg, pulmonary capillary wedge pressure >20 mm Hg and decreased mixed venous oxygen saturation. SMARCAL1 serum protein concentration was significantly increased only before ACC in donors (p= 0.001; not significant for all other time points of measurement) whose grafts developed PGD compared to those whose grafts did not. In receiver operating characteristic curve analysis SMARCAL1 serum concentration before ACC in donors predicted PGD (p= 0.02, AUC= 0.877). At a cut-off level of ≥1.7 ng/mL serum SMARCAL1 in donors before ACC had a sensitivity of 87% and a specificity of 81% to predict PGD. SMARCAL1 serum concentrations ≤1.2 ng/mL in donors before ACC resulted in 85% PGD-free outcome. In a stepwise multivariate logistic regression analysis, the ability of SMARCAL1 to predicr PGD was even superior to hemodynamic and procedure-related parameters (p< 0.001). Serum SMARCAL1 may serve as a predictive marker in the assessment of cardiac graft quality, in particular in marginal donors, before ACC.