Troponin Testing After Cardiac Surgery

Single biomarker measurements can predict outcome after cardiac surgery. and may assist in decision making about diagnostic and therapeutic steps following surgery. Although comparative data are relatively lacking some data exist to suggest that among markers of myocardial necrosis, results from cardiac troponin (cTn) measurement may be superior for risk prediction after cardiac surgery to those from the MB isoenzyme of CK (CK-MB). Loss of cardiac troponins from necrotic myocardium is not replenished through re-expression of genes that might increase protein synthesis, and release of cTn appears to represent irreversibly damaged myocardium. Not every cardiac surgical procedure is associated with the same degree of cTn elevation and forms of cardioprotection may im-portantly affect concentrations of cTn after coronary artery bypass grafting. Similarly, less cardiac injury may occur depending on the form of anesthesia used during surgery. Great caution must be exercised when utilizing cTnT or cTnI for diagnosis of post-cardiac surgery regional acute myocardial infarction: in this context clinical factors must be applied at the risk of a false diagnosis. On the other hand, concentrations of both cTnT and cTnI have repeatedly and unequivocally been shown to be prognostic for delayed recov-ery, intensive care unit utilization, as well as short- and longer-term mortality following cardiac surgery.