Recent assay developments for cardiac troponins. Are we sensitive enough to recognize the high sensitives?

摘要

Cardiac troponins play a major role in the diagnostic work-up of acute coronary syndrome/myocardial infarction. Elevations were demonstrated also in other, rather nonischemic diseases like pulmonary embolism or acute heart failure. Stepwise improvement in the accuracy of the commercially available assays allowed detection of low-level concentrations of cardiac troponins, which were previously partially classified to be normal (between the limit of detection and the 99th percentile by < 10% coefficient of variance). These low concentrations were associated with the detection of chronic cardiovascular pathologies and an increased risk of future cardiovascular events. Recently, ten to 100 times more sensitive assays (so-called high sensitive or ultra sensitive assays) have been developed. The clinical importance of those now measurable troponin values is currently under intensive investigation. The expected additional clinical and prognostic information from such low- and even lowest-level troponin valuespose a special challenge. Specifically, the question has been raised, whether the established single cutoff approach for diagnosing myocardial infarction should not be complemented by another, lower cutoff usable for the detection of other (stable) cardiovascular pathologies with lower but still substantial risk.