FRIDAY, Oct. 21 (HealthDay News) -- A sensitive cardiac troponin I (s-cTnI) assay can predict mortality risk for patients with acute heart failure, according to a study published online Oct. 11 in the Journal of Internal Medicine.
Nisha Arenja, M.D., from the University Hospital Basel in Switzerland, and colleagues investigated the prognostic and diagnostic value of a s-cTnI assay in 667 patients with acute heart failure presenting to the emergency department with acute dyspnea, who were followed for a median of 371 days. S-cTnI was stratified as being below the detection limit (<0.01 µg/L, undetectable), detectable but within the normal range (0.01 to 0.027 µg/L), and increased (≥0.028 µg/L). The final diagnosis was reviewed by two cardiologists.
The investigators found that the s-cTnI levels were significantly higher in patients with acute heart failure than in patients with acute dyspnea attributable to non-cardiac causes (median 0.02 transplant versus <0.01 µg/L). Increasing s-cTnI was associated with elevated in-hospital mortality in all three strata (2, 5, and 14 percent, respectively), and one-year mortality (21, 33, and 47 percent, respectively) for patients with acute heart failure. After adjusting for other risk factors, including B-type natriuretic peptide, s-cTnI remained an independent predictor of one-year mortality. The net reclassification and absolute integrated discrimination improvements were 68 percent and 0.18, respectively. The area under the receiver operating characteristic curve for diagnostic accuracy of s-cTnI in AHF was 0.78.
"Detectable levels of s-cTnI, even within the normal range, are independently associated with mortality," the authors write.