Project Abstract
We aim to investigate which biomarkers are most useful in identifying increased risk for adverse cardiovascular
(CV) and kidney outcomes in patients with heart failure with preserved ejection fraction (HFpEF) and with
reduced ejection fraction (HFrEF). This is imperative because chronic kidney disease (CKD) is common among
patients with heart failure and associated with adverse outcomes. Up to 56% of patients with heart failure suffer
from kidney function decline, subsequently leading to worse CV outcomes, but biomarkers to accurately identify
which patients are at risk for decline in kidney glomerular filtration rate (GFR) are lacking. This not only limits
prognostication, but makes clinical decisions regarding eligibility of patients with HFrEF for advanced therapies
very challenging. Kidney disease can be assessed using GFR, which can be estimated using serum creatinine
(eGFRcr), cystatin C (eGFRcys), or a weighted average of the two (eGFRcr-cys). It is unknown whether eGFRcr,
eGFRcys, or eGFRcr-cys is better at predicting CV outcomes among patients with HFpEF or HFrEF. Additionally,
soluble suppression of tumorogenicity 2 (ST2), and galectin-3 are easily obtainable blood biomarkers that may
be associated with CKD progression and increased mortality, predominantly in patients with HFrEF, but have
not been tested in patients with HFpEF. These biomarkers will be useful in understanding which patients
are at increased risk of GFR decline and adverse CV events. Moreover, identifying such biomarkers will
pave the way for future studies to better understand kidney disease pathogenesis in the setting of heart
failure. To answer these questions, we plan to obtain specimens from the Treatment of Preserved Cardiac
Function Heart Failure With an Aldosterone Antagonist trial (TOPCAT), a study population with HFpEF available
in BioLINCC. Of 3445 participants, 220 have serum samples available at baseline and one year for analysis. We
plan to measure serum cystatin C, ST2, and galectin-3. Our other biomarker of interest, serum creatinine, is
already available in the dataset. We will use these data to: Aim 1a, test the association between baseline and
increasing levels of serum ST2 and galectin-3 with the composite outcome of aborted cardiac arrest, heart failure
hospitalization, or cardiovascular (CV) death; Aim 1b, test the association between baseline and increasing
levels of serum ST2 and galectin-3 and the outcome of change in eGFRcr-cys from baseline to 1 year; Aim 2,
investigate which GFR estimate is more predictive of the composite outcome; and Aim 3, analyze data from the
Registry Evaluation of Vital Information for Ventricular Assist Devices in Ambulatory Life (REVIVAL), which is
also publicly available in BioLINCC and has baseline serum creatinine and cystatin C measurements available,
to evaluate which GFR estimate is the best predictor of all-cause mortality and a composite of heart failure
hospitalization and CV death in patients with HFrEF. The overarching hypotheses are that (1) serum ST2 and
galectin-3 are biomarkers associated with adverse CV and kidney outcomes in HFpEF patients; (2) eGFRcr-cys
is the best GFR estimate to predict adverse outcomes in patients with HFpEF and HFrEF.