Cardiac markers: a clear cause for point-of-care testing

Point-of-care testing (POCT) in patients with ischemic heart disease is driven by the time-critical need for fast, specific, and accurate results to initiate therapy instantly. According to current guidelines, the results of the cardiac marker testing should be available to the physician within 30 min ("vein-to-brain" time) to initiate therapy within 60-90 min ("door-to-needle" time) after the patient has arrived at the emergency room or intensive care unit. This article reviews the current efforts to meet this goal (1) by implementing POCT of established biochemical markers such as cardiac troponins, creatine kinase MB, and myoglobin, in accelerated diagnosis and management workflow schemes, (2) by improving current POCT methods to obtain more accurate, more specific, and even faster tests through the integration of optical and electrochemical sensor technology, and (3) by identifying new markers for the very early and sensitive detection of myocardial ischemia and necrosis. Furthermore, the specific requirements for cardiac POCT in regard to analytical performance, comparability, and diagnostic sensitivity/specificity are discussed. For the future, the integration of new immunooptical and electrochemical chip technology might speed up diagnosis even further. However, every new development will have to meet the stringent method validation criteria set for corresponding central laboratory testing.