Abstract 12920: Double Peak of Cardiac Troponin T in Non ST-Segment Elevation Myocardial Infarction

Abstract

Introduction: cardiac biomarkers are the cornerstone of the biological definition of acute myocardial infarction. In previous literature it was shown that hs-Troponin T blood assay follows a typical biphasic kinetic in patients (pts) affected by ST segment elevation myocardial infarction (STEMI), treated by primary percutaneous coronary intervention (PCI), while this does not appear to be the case for creatinphosphokinase (CPK) and hs-Troponin I assays. Hypothesis: According to these previous data, we studied hs-troponin T and CPK kinetics in pts suffering from non-ST segment elevation myocardial infarction (NSTEMI). Methods: we retrospectively analysed blood samples for cardiac biomarkers in NSTEMI pts consecutively admitted to the coronary care unit of our institution from January 2022 to May 2023. Results: A total of 83 pts were included. 89% of pts were treated by PCI; 98% of these pts received PCI within 24 hours from hospital admission. Among the 83 enrolled pts, only 11% was treated by surgical revascularization and/or anti-ischemic pharmacological therapy. A double peak of hs-troponin T was observed only in pts treated by PCI (p=0,0001). In these pts the mean time to first hs-troponin T peak was at 35,84 ± 4,4 hours while the mean time to second hs-troponin T peak was at 78,62 ± 8,7 hours. CPK value at hospital admission was 208,6 ± 34,8 U/L while first hs-troponin T peak was 560,1 ± 112,9 ng/L; the second hs-troponin T peak was 240,3 ± 33,7 ng/L, in absence of CPK double peak. Conclusions: similarly to previous studies in STEMI pts, our data confirm the presence of hs-troponin T double peak, in the absence of CPK second dispersion, also in NSTEMI pts. The hs-troponin T second peak is strongly related to PCI procedure while pts undergoing conservative treatment or surgical coronary revascularization do not show such a kinetic. Another interesting issue is the absence of CPK second dispersion. This could suggest a potential trivial meaning of hs-troponin T second peak. Therefore, the second peak could not be of any significance for prognostic evaluation and appropriate timing of pts discharge from acute cardiac care units.