High-sensitivity cardiac troponin assays and unstable angina.

The term unstable angina has been conventionally applied to patients with myocardial ischemia without myocardial necrosis. However, while the clinical context has remained constant over time, the biomarkers of myocardial injury and acute myocardial infarction have evolved. High-sensitivity cardiac troponin assays have several key analytical differences from prior cardiac troponin assay generations, which may alter the diagnosis and frequency of unstable angina, as well as affect our understanding of previously developed risk stratification strategies. This document reviews the current challenges in regards to unstable angina when using high-sensitivity cardiac troponin I and T assays.