Evaluierung eines qualitativen schnelltestes fur kardiales troponin T zur praklinischen diagnostik bei patienten mit akutem koronarsyndrom

Objective: To evaluate the practical performance and the diagnostic power of a rapid, qualitative assay for the detection of cardiac Troponin T (indicated cut-off level: 0.3 ng/ml) in EMS patients presenting with acute myocardial ischemia. Patients: 145 consecutive patients with non-traumatic chest pain treated by the Mobile Intensive Care Unit team. During phase 1 (73 patients), blood drawn at the emergency site was used to perform a Troponin T rapid assay under defined conditions at the hospital. During phase 2 (72 patients), the rapid assay was already performed at the emergency site. Results: In phase 1 all tests were performed correctly, whereas 5.6 % of the test results had to be declared unvalid in phase 2. 17 (11.7 %) of the 145 patients showed a positive test result. Analytic sensitivity was 100 %, specificity 96.3 %. 37 of the 145 patients (median duration of symptoms: 150 minutes) showed a myocardial infarction (MI). Related to the diagnosis of MI diagnostic sensitivity, specificity, positive and negative predictive values were 35.1, 96.3, 76.5, and 81.3 %. Mortality in patients with a positive rapid assay was 35.3 %, compared to 6.3 % in patients with a negative test result (p < 0.001). Conclusions: The rapid assay allows the detection of Troponin T in concentrations above the cut-off level. Meticulous observance of the manufacturer's rules is imperative. A single preclinical rapid assay does not allow to exclude a MI. However, the test enables EMS personnel to identify patients who are at increased risk of dying from an acute coronary syndrome in the immediate future.