Use of cytosolic and myofibril markers in the detection of ongoing myocardial damage in patients with chronic heart failure

Purpose Measurement of serum levels of cytosolic and myofibril components of cardiac tissue could indicate ongoing myocardial damage in patients with chronic heart failure. Methods We correlated serum levels of a cytosolic marker (heart-type fatty acid–binding protein) and a myofibril marker (troponin T) with the severity of symptoms (based on the New York Heart Association [NYHA] class), neurohumoral derangement, and subsequent cardiac events in 56 patients with chronic heart failure. Results Mean (± SD) levels of heart-type fatty acid–binding protein were greater in patients with NYHA class III or IV heart failure (9.9 ± 5.2 ng/mL) than in those with NYHA class II (4.9 ± 1.9 ng/mL, P<0.0001). Detection of troponin T (≥0.02 ng/mL) was also more common in patients with worse heart failure (81% [13/16] in class III or IV vs. 43% [17/40] in class II, P = 0.02). Significant correlations were found between heart-type fatty acid–binding protein levels and plasma levels of A-type natriuretic peptide (r = 0.45, P = 0.0004), B-type natriuretic peptide (r = 0.66, P<0.0001), and norepinephrine (r = 0.36, P = 0.006). Male sex (hazard ratio [HR] = 5.0; 95% confidence interval [CI]: 1.3 to 19), detectable troponin T levels (HR = 7.0; 95% CI: 1.1 to 44), heart-type fatty acid–binding protein (HR = 2.6 per 3.9-ng/mL increase; 95% CI: 1.1 to 6.5), and left ventricular ejection fraction (HR = 3.6 per 15% decrease; 95% CI: 1.2 to 11) were independently associated with subsequent cardiac events (8 deaths or 10 readmissions because of worsening heart failure). Conclusion Heart-type fatty acid–binding protein and troponin T are markers of ongoing myocardial damage, and are associated with subsequent cardiac events in patients with chronic heart failure.