Abstract

Takotsubo Syndrome (TTS) is a disease mainly affecting female patients that leads to an acute leftventricular dysfunction. TTS presents like an acute myocardial infarction, however in contrast to acute coronary syndromes coronary perfusion is inconspicuous. Specific biomarker for the diagnosis of TTS are lacking and classical myocardial laboratory parameters cannot discriminate TTS from acute coronary syndromes in the acute setting. Diagnosis bases on exclusion of an underlying coronary culprit lesion and classical left ventricular imaging findings. Aim of the present study was the analyses of myocardial biomarkers including high- sensitivity troponin T (hs-TnT) and the follow-up of left ventricular function in TTS compared to ST-elevation myocardial infarction.

Methods: We included 79 patients with TTS and 85 patients with ST-Elevation Myocardial Infarction (STEMI). Myocardial laboratory parameters including hs-TnT were analysed for both groups and we assessed left-ventricular Ejection Fraction (EF) in the acute setting and three months follow-up by cardiovascular MRI.
Results: We observed significantly lower levels for hs-TnT (TTS: 328pg/ml vs. STEMI: 2544 g/ml; p<0.001) and CK-MB (TTS: 33.5U/l vs. STEMI: 151U/l; p<0.001) in TTS patients. A cut-off value of 1131pg/ml achieves a sensitivity of 100 and specificity 95.9% for the discrimination between TTS and STEMI in our patients. TTS patients showed a lower left-ventricular EF in the initial assessment (EF: 50%) compared to STEMI (EF: 57%). After 6 months we observed a significant improvement in TTS (EF: 65.5%) with only a slightly recovery in STEMI patients (EF: 60%).
Discussion: In our population, we observed lower peak values for hs-TnT and CK-MB in TTS compared to STEMI. A cut-off value may be able to differentiate TTS and STEMI in context of clinical and diagnostic findings with optimal sensitivity in females. Initially reduced left ventricular function in TTS showed a significant greater recovery compared to STEMI patients.

Abbreviations:TTS: Takotsubo Syndrome; CMRI: Cardiovascular Magnetic Resonance Imaging; STEMI: ST- Elevation Myocardial Infarction ; ACS: Acute Coronary Syndromes; LGE: Late Gadolinium Enhancement; LV-EF: Left-Ventricular Ejection Fraction; eGfr: Estimated Glomerular Filtration Rate; SD: Standard Deviation, IQR: Interquartile Range; ROC: Receiver Operating Characteristic; FU-1: First Follow Up