Serum copeptin and copeptin/NT-proBNP ratio - new tools to differentiate takotsubo syndrome from acute myocardial infarction.

Background: Today no established biomarkers are available for the early diagnosis of takotsubo syndrome and its differentiation from ST-segment elevation myocardial infarction. We hypothesized that copeptin and copeptin/NT-proBNP ratio may serve a routine marker combination for non-invasive differentiation.
Methods: The study compared the serum concentrations of copeptin, troponin I (TnI) and NT-proBNP in 19 consecutive women diagnosed with takotsubo syndrome according to the Mayo Clinic criteria and 10 consecutive women diagnosed with ST-segment elevation myocardial infarction.
Results: Copeptin concentrations were significantly lower in patients with takotsubo syndrome than in patients with ST-segment elevation myocardial infarction. The diagnostic accuracy to distinguish takotsubo syndrome from ST-segment elevation myocardial infarction is highest for copeptin/NTproBNP ratio, copeptin/TnI at admission ratio and copeptin alone (AUC 0.8713, 0.8538, 0.8480, respectively).
Conclusions: The serum copeptin to NTproBNP ratio could be an additional tool in the non-invasive differentiation between takotsubo syndrome and ST-segment elevation myocardial infarction. However, further researches are needed.