Prognosis, Prognosis, Wherefore Art Thou Prognosis?

Abstract

As this investigative team aptly notes, uptake of hs-Tn in the US has lagged compared to the rest of the world. While reasons for this lie primarily with approval delays at the Food and Drug Administration (FDA), there remains a reluctance in many institutions to shift from conventional assays to more sensitive counterparts. When pressed, decision makers at such facilities point to the absence of US data and feign uncertainty about potential accuracy in their patient populations. It is within this void that Peackock et al present new(ish) data on Beckman Coulter's high sensitivity troponin I (hsTnI) assay, showing that it can reliably identify emergency department (ED) patients with suspected acute coronary syndrome (ACS) who have not sustained myocardial injury. Such work is important from a validation perspective, though incremental at best, providing information that is really a mirror image of itself (i.e, absence of of a protein that reflects myocardial injury indicates absence of myocardial injury). Said another way, publication of data showing that the Beckman Coulter hsTnI assay can effectively rule out myocardial injury may be necessary to convince skeptics of its safety profile but the exercise is merely revealing an inherent truth based on known characteristics of the underlying pathophysiology and lab medicine. That this analysis included an all-comer prospective cohort of ED patients does make the findings unique and adds to applicability, though it does not alter this perspective.