Soluble fibrin monomer complex assay enhances early and accurate diagnosis of acute myocardial infarction

Abstract

Background: Soluble fibrin monomer complex (SFMC) was shown to be raised in patients with acute myocardial infarction (AMI). It provides information regarding fibrin formation prior to thrombus formation and the development of myocardial cell damage in thrombosis-mediated type 1 MI. The introduction of high sensitivity cardiac troponin assays has increased the diagnostic sensitivity (SE) for diagnosis of MI, but the diagnostic specificity (SP) was compromised. Such a defect was partially conformed by recommending serial measurements, which comes at the expense of a timely definitive diagnosis. We suppose that SFMC can act as an advantageous marker to promote the diagnostic performance of sensitive cardiac troponin I (s-cTnI) to diagnose AMI using the on-admission sample of acute chest pain patients. Methods and findings: s-cTnI and SFMC were assayed in 75 acute chest pain patients presenting within 3 hours of symptoms onset and 20 healthy control subjects. Thirty-five patients were diagnosed as having AMI, and 40 patients had non-AMI chest pain. Either marker was significantly higher in AMI. The receiver operating characteristic-area under the curve, SP and positive predictive value (PPV) of the combined use of both markers were 0.985, 97.5% and 97%, respectively, which were higher than the values for s-cTnI (0.903, 85%, 84.2%, respectively) or SFMC (0.946, 90%, 89.5%, respectively). No improvement of SE or negative predictive value was noted on simultaneous use of both markers. Conclusion: adding SFMC to s-cTnI during early stages of acute chest pain has promoted the diagnostic accuracy of s-cTnI in terms of SP and PPV.