Aborted myocardial infarction: is it real in the troponin era?

Abstract

Background: Cardiac troponins are the markers of choice for the diagnosis of acute myocardial infarction. The objective of this study was to compare the frequency of "aborted myocardial infarction" (no detectable myocardial injury) determined by measurement of troponin versus that determined by creatine kinase (CK) and creatine kinase-muscle brain (CK-MB) measurement criteria among patients with ST-elevation myocardial infarction (STEMI) who received reperfusion therapy.

Methods: Since 2004, the Mayo Clinic (Rochester, MN) has had a standard reperfusion protocol for the treatment of patients with STEMI. During the study period, 767 patients presented with new or presumed new ST elevation or left bundle block.

Results: The diagnosis of STEMI was confirmed in 765 (99.7%) patients. Using the 99th percentile cutoff value, troponin T elevations occurred in 765 (100%) of 765 patients when serial samples were available. Creatine kinase-MB levels of twice or more the upper limit of normal occurred in 681 (90.1%) of 749 patients with serial samples for CK-MB, and CK equal or greater than twice the gender-specific upper limits of normal occurred in 521 (78.8%) of 661 patients with serial samples for CK available.

Conclusion: The frequency of aborted myocardial infarction is 0% when using troponin at the 99th percentile cutoff as recommended by contemporary guidelines from the European Society of Cardiology (Nice, France) and American College of Cardiology (Washington, DC).