Research news: October 2009
Two prospective multicentre studies looked at the diagnostic accuracy of new generation sensitive troponin assays for diagnosing myocardial infarction. In one study, cardiac troponin concentrations were determined by using four sensitive assays and a standard assay, in a blinded fashion, in 718 consecutive patients with suspected myocardial infarction. Two cardiologists independently made the final diagnosis on the basis of each patient’s full medical record. The sensitive assays topped the standard assay in diagnostic accuracy, with areas under the receiver operating characteristic (ROC) curve ranging from 0.95 to 0.96, compared with 0.90 for the standard assay. The difference was most pronounced in patients who presented within three hours of symptom onset, with values ranging between 0.92 to 0.94 for sensitive assays, compared with 0.76 for the standard assay. The new assays were of limited value in diagnosing unstable angina, however.
Another study enrolled 1818 consecutive patients and compared Siemens troponin I