Evaluation of d-Dimer for the exclusion of myocardial infarction in conjunction with troponin I in an emergency department

• Published in: Annals of emergency medicine 2004-10, Vol.44 (4), p.S15-S16
• Main Authors: Nsiri, B., Mazigh, C., Barakett, N., Balma, A.
• Format: Article
• Language: English
• ISSN: 0196-0644; 1097-6760
• DOI: 10.1016/j.annemergmed.2004.07.051

Study objectives: Chest pain is a frequent symptom in the emergency department (ED) and often presents a diagnostic challenge. Some published studies have shown that hemostatic markers had a diagnostic value in patients presenting to the ED with chest pain or shortness of breath. This study, performed in our military hospital, was aimed to demonstrate that d-dimer associated with troponin (bioMérieux SA, France) could be used as an exclusion test for patients suspected of having myocardial infarction in the ED, thus enabling a reduction of the patient hospital stay and cost savings. Methods: One hundred nineteen consecutive patients presenting with chest pain selected within the hospital ED were included in this prospective study during 6 months. T0 corresponds to the onset of chest pain. Fresh plasma samples collected from those patients were tested with the VIDAS d-Dimer New and VIDAS Troponin assays at different times. T1 corresponds to the time of the first sample collection at patient arrival, T2 corresponds to T1+6 hours. Troponin I cutoff was fixed at 0.8 μg/L as described previously; d-dimer cutoff was fixed at 250 ng/mL. An ECG was performed for all patients. Patients were classified into 4 categories: normal, stable angina, unstable angina, and myocardial infarction. Results: The results obtained are consolidated in the Table. For the diagnosis of myocardial infarction at T1, troponin I alone gave a sensitivity of 46.2% and a specificity of 96.8%, whereas at T2, the sensitivity was 96.2% and the specificity was 96.8%. At T1, d-dimer showed a sensitivity of 88.5% and a specificity of 25.8%. When we associated both troponin I and d-dimer assays, the sensitivity was 96.2% and the specificity was 25.8%. The combination of the 2 parameters allowed us to exclude 24 patients (20% of the total population) at T1, 1 patient remaining false negative. Conclusion: The association of d-dimer and troponin can safely enable the exclusion of myocardial infarction in an ED population and may be incorporated into clinical decision models in EDs.Table, abstract 46T1No. of Patientsd-Dimer Value at T1, ng/mLd-Dimer Value at T2, ng/mLNormal29971.25±1765822±1312Stable angina14532.78±386718±1208Unstable angina50757.9±1064796±1108Myocardial infarction26958.46±11431148±1322