Biomarkers of myocardial ischemia in the emergency room: cardiospecific troponin and beyond

A timely and efficient diagnosis is critical in patients with chest pain, to optimize the efficacy of myocardial revascularization in those with an acute coronary syndrome, and offset the increasing overcrowding in the emergency room by early discharge of subjects without myocardial ischemia. Although cardiospecific troponins remain the biochemical gold standards for diagnosing an acute coronary syndrome, several additional biomarkers have been proposed. As a general rule, there are important issues that should be addressed when combining an innovative diagnostic test with troponin, including a benchmark evaluation of diagnostic performance, the impact on throughput and turnaround time, along with the analytical features of the assay and the cost to benefit ratio of a multi-marker approach. Despite a considerable amount of data has been published, there is insufficient analytical and clinical evidence to support the use of most of these novel biomarkers as surrogates or in combination with troponin for diagnosing ischemic heart disease, especially when the latter is assessed with the novel highly-sensitive immunoassays.