Coronary sinus biomarker sampling compared to peripheral venous blood for predicting outcomes in patients with severe heart failure undergoing cardiac resynchronization therapy: the BIOCRT study

Abstract

Background: A significant minority of patients receiving cardiac resynchronization therapy (CRT) remain nonresponsive to this intervention.

Objective: This study aimed to determine whether coronary sinus (CS) or baseline peripheral venous (PV) levels of established and emerging heart failure (HF) biomarkers are predictive of CRT outcomes.

Methods: In 73 patients (aged 68 ± 12 years; 83% men; ejection fraction 27% ± 7%) with CS and PV blood samples drawn simultaneously at the time of CRT device implantation, we measured amino-terminal pro-B-type natriuretic peptide (NT-proBNP), galectin-3 (gal-3), and soluble ST2 (sST2) levels. NT-proBNP concentrations >2000 pg/mL, gal-3 concentrations >25.9 ng/mL, and sST2 concentrations >35 ng/mL were considered positive on the basis of established PV cut points for identifying "high-risk" individuals with HF. CRT response was adjudicated by the HF Clinical Composite Score. A major adverse cardiovascular event (MACE) was defined as the composite end point of death, cardiac transplant, left ventricular assist device, and HF hospitalization at 2 years.

Results: NT-proBNP concentrations were 20% higher in the CS than in the periphery, while gal-3 and sST2 concentrations were 10% higher in the periphery than in the CS (all P < .001). There were 45% CRT nonresponders at 6 months and 16 (22%) patients with MACE. Triple-positive CS values yielded the highest specificity of 95% for predicting CRT nonresponse. Consistently, CS strategies identified patients at higher risk of developing MACE, with >11-fold adjusted increase for triple-positive CS patients compared to triple-negative patients (all P ≤ .04). PV strategies were not predictive of MACE.

Conclusion: Our findings suggest that CS sampling of HF biomarkers may be better than PV sampling for predicting CRT outcomes. Larger studies are needed to confirm our findings.

Keywords: Biomarker; Cardiac resynchronization therapy; Coronary sinus; Galectin-3; Soluble ST2.

Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Figures

Figure 1

Kaplan-Meier curves for predicting MACE as stratified by triple marker strategy for coronary sinus (A) and peripheral venous (B) samples.