Rapid and accurate diagnosis of heart attacks—and the assessment of damage—is critical for improving coronary care. Mature microRNAs (miRNAs) are abundant, easily measured, and relatively stable in blood plasma. If they prove indicative of disease states, miRNAs measured from peripheral blood may be a particularly attractive source for routine clinical assessments.1
Naoharu Iwai’s lab in Osaka, Japan, and Stephane Heymans and Blanche Schroen in Maastricht, Netherlands, found greatly elevated levels of cardiac myocyte–associated miRNAs in the plasma of patients with acute myocardial infarction (AMI).2,3 Increased plasma levels of the mature miRNAs miR-208b and -499 were consistently seen in AMI patients regardless of age, sex, body mass index, systolic blood pressure, and white blood cell count. Importantly, levels of these miRNAs correlated with concentrations of cardiac troponin, currently the best clinical marker for AMI. Unlike troponin, which can also indicate renal dysfunction, these miRNAs appeared to be specific for AMI. Detection ...