A call for universal definition of myocardial infarction after cardiac surgery

Defining concepts that enable clinicians and patients to communicate effectively concerning myocardial infarction associated with cardiac surgery requires an accurate, clear and easily interpreted definition. If the diagnostic criteria are accurate and reproducible, it will facilitate clinical care and clinical trials. Furthermore, it would allow for results from 1 clinical trial to be compared and even combined with the results of other trials. Unfortunately, the ideal world of a universally understood and applied definition does not exist in the domain of procedure-related myocardial infarction (PMI). Over the years differing definitions using different diagnostic tools have been employed and consequently, it is often a challenge to compare the ‘apples’ in 1 study to the ‘oranges’ in another. Thus, studies involving large databases employing hospital discharge diagnoses often contain significant inaccuracies since the definitions of PMI employed are highly variable. the proposed revision accounts for approximately two-thirds of PMIs whereas non-graft-related causes subsume the rest and are more frequent in patients undergoing combined surgical procedures [5]. The extent of biomarker elevation differs across different cardiac surgical procedures showing the highest levels after more extensive surgery, such as combined valve and CABG surgery and isolated mitral valve surgery, and the lowest levels after isolated aortic valve replacement and isolated CABG [4]. Being so, it’s not surprising that definitions of PMI relying solely on the release of biomarkers release have generated substantial controversy, and there is no general consensus on cut-off values to be used [6]. Thus, as we have begun to appreciate some prognostic signals, usually increased mortality, there has been a call to use these prognostic thresholds as the paper from the EACTS group suggests [4].