The Prognostic Significance of Biomarkers in Predicting Outcome in Patients With Coronary Artery Disease and Left Ventricular Dysfunction: Results of the Biomarker Sub-Study of the Surgical Treatment for Ischemic Heart Failure (STICH) Trials.
Circ Heart Fail. 2013 Apr 12;
Authors: Feldman AM, Mann DL, She L, Bristow MR, Maisel AS, McNamara DM, Walsh R, Lee DL, Wos S, Lang I, Wells G, Drazner MH, Schmedtje JF, Pauly DF, Sueta CA, Di Maio M, Kron IL, Velazquez EJ, Lee KL
Abstract
BACKGROUND: -Patients with heart failure and coronary artery disease often undergo coronary artery bypass grafting (CABG) but assessment of the risk of an adverse outcome in these patients is difficult. To evaluate the ability of biomarkers to contribute independent prognostic information in these patients, we measured levels in patients enrolled in the Biomarker Sub-studies of the Surgical Treatment for Ischemic Heart Failure (STICH) trials. Patients in STICH Hypothesis 1 were randomized to medical therapy or CABG whereas those in STICH Hypothesis 2 were randomized to CABG or CABG with left ventricular reconstruction. METHODS AND RESULTS: -In sub-study patients assigned to STICH Hypothesis 1 (n=606), plasma levels of sTNFR-1 and BNP were highly predictive of the primary outcome variable of mortality by univariate analysis (BNP χ(2)=40.6; p<0.0001: sTNFR-1 χ(2)=38,9; p<0.0001). When considered in the context of multivariable analysis, both BNP and sTNFR-1 contributed independent prognostic information beyond the information provided by a large array of clinical factors independent of treatment assignment. Consistent results were seen when assessing the predictive value of BNP and sTNFR-1 in patients assigned to STICH Hypothesis 2 (n=626). Both plasma levels of BNP (χ(2)=30.3) and sTNFR-1 (χ(2)=45.5) were highly predictive in univariate analysis (p<0.0001) as well as in multivariable analysis for the primary endpoint of death or cardiac hospitalization. In multivariable analysis, the prognostic information contributed by BNP (χ(2)=6.0; p=0.049) and sTNFR-1 (χ(2)=8.8; p=0.003) remained statistically significant even after accounting for other clinical information. Although the biomarkers added little discriminatory improvement to the clinical factors (increase in c-index ≤ 0.1), Net Reclassification Improvement (NRI) for the primary endpoints was 0.29 for BNP and 0.21 for sTNFR-1in the Hypothesis 1 cohort, and 0.15 for BNP and 0.30 for sTNFR-1 in the Hypothesis 2 cohort, reflecting important predictive improvement. CONCLUSIONS: -Elevated levels of sTNFR-1 and BNP are strongly associated with outcomes, independent of therapy, in two large and independent studies, thus providing important cross-validation for the prognostic importance of these two biomarkers.
PMID: 23584092 [PubMed - as supplied by publisher]