Abstract 13230: Serum Cystatin C is an Alternative Measure of Renal Function and is Superior to Serum Creatinine for Prediction of Adverse Events in Left Ventricular Assist Device Patients

IntroductionEstimated glomerular filtration rate (eGFR) is reported to improve shortly after left ventricular assist device (LVAD) and is also predictive of adverse events. However, changes in muscle mass (MM) may affect the accuracy of serum creatinine (sCr) based eGFR. Cystatin C (CysC) estimates GFR independent of MM. We aimed to1) investigate changes in MM and their association with sCr in the early post LVAD period; 2) compare sCr and CysC based eGFR at serial time points and their predictive value for adverse events in LVAD pts.MethodsTwo cohorts of LVAD pts were studied1) a retrospective cohort (RC; 93 pts) with chest CTs available 1-40 days post LVAD; 2) a prospective cohort (PC; 86 pts, 154 samples) with serial measures of sCr and CysC pre and post LVAD implantation. In the RC, unilateral pectoralis muscle area indexed to body surface area (PMI, 1 U = 1 cm/m) was measured. In the RC, multivariable linear regression was used to assess the association between PMI and i) time after LVAD; and ii) sCr at 1 month post LVAD. In the PC, eGFR was calculated by MDRD4 (MDRD4-eGFR) and CKD-EPI-CysC (CysC-eGFR). Predictive value of pre LVAD MDRD4- vs. CysC-eGFR for a composite of post LVAD renal replacement therapy (RRT) or right ventricular failure (RVF) was compared.ResultsIn the RC, median PMI was 6 (2.6-20) U at a median of 13 days post LVAD. In fully adjusted modelsi) for every 5 additional days post LVAD, there was a 6% decrease in PMI; ii) for every 1 U decrease in PMI, 1-month sCr decreased by 4%, independently from pre LVAD sCr (all p