Background: Cardiac troponin I (cTnI), a sensitive and specific marker of myocardial cell injury, is useful in diagnosing and assessing prognosis in acute coronary syndromes. Small studies report that cTnI is elevated in severe heart failure (HF) and may predict adverse outcomes.
Methods and results: The present study evaluated 238 patients with advanced HF referred for cardiac transplantation evaluation who had cTnI assay drawn at the time of initial presentation. Patients with acute myocardial infarction or myocarditis were excluded from analysis. cTnI was detectable (cTnI > or =0.04 ng/mL) in serum of 117 patients (49.1%). Patients with detectable cTnI levels had significantly higher B-type natriuretic peptide (BNP) levels (P<0.001) and more impaired hemodynamic profiles, including higher pulmonary wedge pressures (P=0.002) and lower cardiac indexes (P<0.0001). A significant correlation was found between detectable cTnI and progressive decline in ejection fraction over time. Furthermore, detectable cTnI was associated with increased mortality risk (RR, 2.05; 95% CI, 1.22 to 3.43). After adjustment for other factors associated with adverse prognosis including age, sex, ejection fraction, and coronary artery disease, cTnI remained a significant predictor of death. cTnI used in conjunction with BNP further improved prognostic value.
Conclusions: cTnI is associated with impaired hemodynamics, elevated BNP levels, and progressive left ventricular dysfunction in patients with HF. cTnI may be a novel, useful tool in identifying patients with HF who are at increased risk for progressive ventricular dysfunction and death.