Biomarkers play a key role in the diagnostic workup of patients presenting to an emergency department (ED). European and American guidelines recommend cardiac Troponin (T or I) as the biomarker gold standard for the diagnosis of non-ST-elevation myocardial infarction (non-STEMI). Today, high-sensitivitiy assays are available and allow an early diagnosis of non-STEMI and the detection of troponin in individuals that would have been classified as unstable angina with former assays. As many patients are detected with elevated troponin values with the high sensitivity assays, specificity for non-STEMI has inevitably decreased. Micro-RNAs (mi-RNA) are new biomarkers with a wide spectrum of detectable conditions that allow specific identification of myocardial infarction. The aim of this study is to develop a biomarker protocol that combines the high sensitivity of cardiac Troponin T and the high specificity of mi-RNA profiles for early and safe identification of non-STEMI in ED patients.

Inclusion Criteria:

• Patients admitted to the emergency department ("chest pain unit"), Dept. of Cardiology, University Hospital Heidelberg
• Symptoms suggestive of ACS incl. chest pain, dyspnea, atypical pain
• Age >= 18 years
• Written informed consent

Exclusion Criteria:

• Mental disorders, dementia
• Pregnancy, breast feeding
• Age < 18 years

Patients presenting to the emergency department with symptoms suggestive of acute coronary syndrome.