Cardiac troponin T levels and exercise stress testing in patients with suspected coronary artery disease: the Akershus Cardiac Examination (ACE) 1 study

Abstract

Whether reversible ischaemia in patients referred for exercise stress testing and MPI (myocardial perfusion imaging) is associated with changes in circulating cTn (cardiac troponin) levels is controversial. We measured cTnT with a sensitive assay before, immediately after peak exercise and 1.5 and 4.5 h after exercise stress testing in 198 patients referred for MPI. In total, 19 patients were classified as having reversible myocardial ischaemia. cTnT levels were significantly higher in patients with reversible myocardial ischaemia on MPI at baseline, at peak exercise and after 1.5 h, but not at 4.5 h post-exercise. In patients with reversible ischaemia on MPI, cTnT levels did not change significantly after exercise stress testing [11.1 (5.2–14.9) ng/l at baseline compared with 10.5 (7.2–16.3) ng/l at 4.5 h post-exercise, P=0.27; values are medians (interquartile range)]. Conversely, cTnT levels increased significantly during testing in patients without reversible myocardial ischaemia [5.4 (3.0–9.0) ng/l at baseline compared with 7.5 (4.6–12.4) ng/l, P<0.001]. In conclusion, baseline cTnT levels are higher in patients with MPI evidence of reversible myocardial ischaemia than those without reversible ischaemia. However, although cTnT levels increase during exercise stress testing in patients without evidence of reversible ischaemia, this response appears to be blunted in patients with evidence of reversible ischaemia. Mechanisms other than reversible myocardial ischaemia may play a role for acute exercise-induced increases in circulating cTnT levels.

Troponin I Measured by a High-Sensitivity Assay in Patients with Suspected Reversible Myocardial Ischemia: Data from the Akershus Cardiac Examination (ACE) 1 Study

“…This hypothesis also has some support in the literature. In a previous publication from the ACE 1 study, we found no association between reversible myocardial ischemia and the release of hs-cTnT during exercise stress testing (19 ). Although the modest number of patients with reversible ischemia in our study may increase the likelihood of a type II error, the lack of increment in hs-cTnT concentrations after exercise stress testing is in accordance with earlier results by Kurz et al (18 ).…”

“…The study protocol of the ACE 1 study has been reported (19,21 ). We included consecutive patients according to a stratified protocol with 50 patients included from the low-risk stratum (Ͻ33% probability of stable CAD), 100 patients from the intermediaterisk stratum (33%-67%), and 50 patients from the high-risk stratum (Ͼ67%).…”

“…cTnT concentrations were measured by a commercially available assay, the Elecsys TNT hs STAT (Roche Diagnostics: reagent lot #156593, calibrator lot #154103, released September 2009) and were not affected by decreased recovery or the introduction of a revised calibration curve (see the Data Supplement that accompanies the online version of this article at http://www.clinchem.org/content/ vol58/issue11). Thus, cTnT measurements were performed as previously reported (19 ) and with an analytical measurement range of 3-10000 ng/L (23 ). CVs in our laboratory were Ͻ10% for hs-cTnT ϭ 13 ng/L, 3.4% for hs-cTnT ϭ 25 ng/L, 2.5% for hs-cTnT ϭ 70 ng/L, and 3.0% for hs-cTnT ϭ 1000 ng/L (n Ն 24).…”

Modern High-Sensitive Troponin Diagnostic Methods in Assessment of Myocardial Ischemia and Prognostical Value for Chronic Coronary Heart Disease

“…Повышение hs-cTnТ при дозированных нагрузоч-ных тестах у больных СтСт наблюдали также в иссле-довании АСЕ (Akershus Cardiac Examination Study) [21]. Исследования проведены у 198 пациентов, среди которых были здоровые лица и больные со СтСт.…”

Myocardial infarction after carotid endarterectomy

“…В результате этого сердечная мышца подвержена большему риску на-растания ишемии. После интубации существует риск об-острения ХОБЛ, что приводит к повышению ферментов, являющихся диагностическими критериями ОИМ [11]. Поэтому минимальные изменения на кардиограмме и по-следующие тесты на тропонин Т могут являться критери-ями выставления диагноза ИМ у больных с умеренными проявлениями ишемии.…”