Small changes in Troponin T levels are common in patients with non-ST-elevation myocardial infarction and are linked to higher mortality.
J Am Coll Cardiol. 2013 Jul 29;
Authors: Bjurman C, Larsson M, Johanson P, Petzold M, Lindahl B, Fu ML, Hammarsten O
Abstract
OBJECTIVE: To examine the extent of change in Troponin T levels in patients with non-ST-elevation myocardial infarction (NSTEMI).
BACKGROUND: Changes in cardiac troponin levels are required for the diagnosis of NSTEMI, according to the new universal definition of acute myocardial infarction. A relative change of 20-230 % and an absolute change of 7- 9 ng/L have been suggested as cut-off points.
METHOD: In a clinical setting, where a change in cTnT was not mandatory for the diagnosis of NSTEMI, serial samples of cTnT were measured with a high-sensitive cTnT (hs-cTnT) assay, and 37 clinical parameters were evaluated in 1178 patients with a final diagnosis of NSTEMI presenting <24h after symptom onset.
RESULTS: After six hours of observation, the relative change in the hs-cTnT level remained <20 % in 26 % and the absolute change <9 ng/L in 12 % of the NSTEMI patients. A relative hs-cTnT change <20% was linked to higher long-term mortality across quartiles (p=0.002) and in multivariate analyses (HR 1.61 (1.17-2.21) p=0.004), whereas 30-day mortality was similar across quartiles of relative hs-cTnT change CONCLUSION: Because stable hs-TnT levels are common in patients with a clinical diagnosis of NSTEMI in our hospital, a small hs-cTnT change may not be useful to exclude NSTEMI, particularly as these patients show both short-term and long-term mortality at least as high as patients with large changes in hs-cTnT.
PMID: 23933541 [PubMed - as supplied by publisher]