Portal de Periódicos da CAPES

Small Changes in Troponin T Levels Are Common in Patients With Non–ST-Segment Elevation Myocardial Infarction and Are Linked to Higher Mortality

2013; Elsevier BV; Volume: 62; Issue: 14 Linguagem: Inglês

10.1016/j.jacc.2013.06.050

1558-3597

Christian Bjurman, Mårten Larsson, Per Johanson, Max Petzold, Bertil Lindahl, Michael Fu, Ola Hammarsten,

Cardiac Imaging and Diagnostics

The purpose of this study was to examine the extent of change in troponin T levels in patients with non–ST-segment elevation myocardial infarction (NSTEMI). Changes in cardiac troponin T (cTnT) levels are required for the diagnosis of NSTEMI, according to the new universal definition of acute myocardial infarction. A relative change of 20% to 230% and an absolute change of 7 to 9 ng/l have been suggested as cutoff points. 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-sensitivity cTnT (hs-cTnT) assay, and 37 clinical parameters were evaluated in 1,178 patients with a final diagnosis of NSTEMI presenting <24 h after symptom onset. After 6 h 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 (hazard ratio: 1.61 [95% confidence interval: 1.17 to 2.21], p = 0.004), whereas 30-day mortality was similar across quartiles of relative hs-cTnT change. 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.