Cardiac Troponins Assessed for Acute Heart Failure

Heart failure (HF) is a clinical syndrome characterized by dyspnea, peripheral edema and fatigue. Diagnosing HF can be difficult due to overlapping symptoms with other conditions, and the phenotype of HF varies due to a broad spectrum of underlying pathophysiology.

Cardiac troponins are cornerstone markers for diagnosis, risk stratification and selection of treatment strategy of acute coronary syndrome (ACS). The diagnostic accuracy for ACS has greatly improved, due to novel high-sensitivity cardiac troponin (hs-cTn) assays with very low limit of detection.

A team of Medical Scientists from the Akershus University Hospital (Lørenskog, Norway) and their colleagues carried out a prospective, single-center study at the hospital conducted from June 2009 through November 2010. Of 468 patients hospitalized with acute dyspnea, 314 patients were included in the final study cohort. Blood samples were obtained within 24 hours of hospital admission in all 231 patients, and day 2 and from 95 patients before discharge, in a subgroup of the cohort. Samples were centrifuged, serum immediately frozen and stored at −80 °C before analysis. In the total population, median age was 73 years and 48% were women.

To measure cTnT concentrations, the team used the high-sensitivity assay, Elecsys TnT hs stat, (Roche Diagnostics, Penzberg, Germany). The assay has a range of detection from 3 to 10,000 ng/L, a 10% coefficient of variation of 13 ng/l, and a 99th percentile in healthy individuals of 14 ng/L. hs-cTnT values below the limit of detection were assigned the value 3 ng/L. N-terminal pro-B-type natriuretic peptide (NT-proBNP) was measured on a Cobas Platform (Roche Diagnostics, Basel, Switzerland) using the proBNP II assay, with a range of detection from 5 to 35,000 ng/L.

The team reported that 143 patients were categorized as AHF (46%) and these patients had higher hs-cTnT concentrations than patients with non-AHF-related dyspnea: median 38 (Q1-3 22–75) versus 13 (4–25) ng/L. hs-cTnT concentrations were similar between patients with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF), in contrast to NT-proBNP, which was higher in HFrEF. During median 27 months of follow-up, 114 (36%) patients died in the total population. Higher hs-cTnT concentrations were associated with increased risk of all-cause mortality after adjustment for clinical variables and NT-proBNP: hazard ratio 1.30 (95% CI 1.07–1.58).

The authors concluded that hs-cTnT provides useful diagnostic information among patients admitted to the Emergency Department with dyspnea. In particular, elevated hs-cTnT seems to be valuable in identifying patients with HFpEF. The hs-cTnT also provides prognostic information for an unselected population with dyspnea, but a larger cohort is needed to examine the prognostic value of hs-cTnT for the subgroup of HF/HFrEF/HFpEF patients. The study was published in the February 2021 issue of the journal Clinical Biochemistry.

Related Links:
Akershus University Hospital
Roche Diagnostics Germany
Roche Diagnostics