Do we really need high-sensitivity troponin immunoassays in the emergency department? Maybe not

The diagnosis of acute coronary syndrome (ACS) has challenged the minds of cardiologists, emergency physicians and laboratorists for decades. A major breakthrough has, however, occurred at the dawn of the third millennium, with development, commercialization and introduction into clinical practice of troponin immunoassays. A novel generation of these methods, conventionally defined as "high-sensitivity" (HS), has more recently emerged. These latest generation assays are characterized by improved analytical sensitivity, which would theoretically allow earlier and more efficient diagnosis of ACS. Despite the considerable amount of information gathered over the past few years about the clinical use of conventional and HS immunoassays, several doubts persist and - according to our personal perspective - the evidence that the latest generation methods would represent a real breakthrough in management of patients in short-stay units such as the emergency department is still an unresolved issue. Beside the mystifying nomenclature that characterizes several commercial tests, recent evidence suggests that the diagnostic performance of some contemporary sensitive methods would equal those of HS immunoassays for early diagnosis, serial assessment and even prognostication of patients. Conversely, the better diagnostic specificity of conventional methods may represent an advantage for triaging patients in overcrowded emergency departments. There is hence a tangible threat that the measurement of troponin with HS methods would become more or less an "expensive cholesterol of the third millennium", and this risk must be carefully considered in a world of limited resources. So, our answer to the question if we do really need HS troponin immunoassays in the emergency department is "maybe not".