Background: Chest pain is a frequent symptom in the emergency department and often presents a diagnostic challenge. Because coronary thrombosis is a hallmark of acute ischemic syndromes, the substrates of the coagulation and fibrinolysis cascades may be markers of coronary ischemia. The objective of this study was to determine the diagnostic value of several hemostatic markers in patients presenting to the emergency department (ED) with chest pain syndromes.
Methods: Two hundred fifty-seven consecutive patients with acute chest pain were studied in this prospective study conducted in an urban ED. D-Dimer levels were measured at admission to the ED in all patients. We also measured thrombin-antithrombin complexes, prothrombin fragment 1+2, activated factor VII, and fibrinogen. We used regression analysis to estimate the likelihood of myocardial infarction and the diagnostic value of D-dimer.
Results: D-Dimer and fibrinogen levels were significantly higher in patients with acute ischemic events (myocardial infarction and unstable angina) than in nonischemic patients (P <.01 and P =.02, respectively). The other hemostatic markers were not significantly elevated in patients with ischemic events. D-Dimer level >500 microg/L had an independent diagnostic value for myocardial infarction and increased the diagnostic sensitivity of the electrocardiogram and history from 73% to 92%.
Conclusion: D-Dimer, an expression of ongoing thrombus formation and lysis, is a marker of substantial incremental value for the early diagnosis of acute coronary syndromes presenting with chest pain. It adds independent information to the traditional assessment for myocardial infarction. D-Dimer can be incorporated into clinical decision models in the ED.