The majority of patients that present at the CCU with suspicion of Acute Coronary Syndrome, do not show ST elevations on ECG and need additional testing of serum cardiac troponinT over time (9-12h), to detect or rule out cardiac disease. The discovery of novel biomarkers that enable diagnostic testing is of importance to detect/rule out MI at an earlier stage, reducing unnecessary hospitalization.Methods and Results
We evaluated the mRNA expression levels of TLR2 and TLR4 by realtime PCR in whole blood samples obtained from 35 patients with acute myocardial infarction with ST elevation, enrolled in the EXAMI trial, at presentation at the CCU and after 4 months (considered baseline). We confirmed that TLRs are upregulated during MI. We identified for the first time a correlation of both TLR2- and TLR4 mRNA levels with infarct size (R=0.59, p=0.0003 and R=0.46, p=0.007). Furthermore we showed that both TLRs are upregulated earlier than troponinT: 25 of 26 patients who still had negative troponinT tests, did already show significantly elevated TLR4 mRNA levels, while 9 of these 26 troponinT-negative patients showed elevated TLR2 levels.Conclusions
TLR2 and TLR4 expression levels correlate with infarct size and are expressed earlier than troponinT, indicating that TLR2 and 4 are early and sensitive markers for MI, which will be evaluated as a diagnostic tool in our future research.