The measurement of cardiac markers is still the gold standard for diagnosing myocardial infarction (MI), but there is always a transition period between the time of infarction and when a marker can be measured in the blood. Therefore, clinicians are shifting their focus to the identification of potential new analytes capable of predicting MIs before the standard cardiac markers increase. In this study, we tested whether measurement of the concentration of soluble intercellular adhesion molecule 1 (sICAM-1) in plasma can be used for this purpose.
In this prospective study, we included 60 male patients who had a left main coronary artery lesion or a left main equivalent and who underwent elective (group I, n = 20), urgent (group II, n = 20), or emergent (group III, n = 20) coronary artery bypass grafting (CABG). We excluded patients who had increased cardiac markers at admission, and drew blood samples for sICAM-1 measurements from other patients immediately after coronary angiography evaluations. We divided the patients into 3 groups according to their clinical characteristics and cardiac marker levels. Only patients with increased cardiac markers underwent emergent CABG (group III). We measured sICAM-1 concentrations immediately after coronary angiography and measured creatine kinase MB (CK-MB) and cardiac troponin I (cTnI) just before CABG. We then evaluated the results for correlations.
CK-MB, cTnI, and sICAM-1 levels were significantly higher in group III than in groups I and II (P < .05 for all). Our analysis for correlations between the sICAM-1 level and cardiac marker levels revealed no significant correlations in group I (CK-MB, r = 0.241 [P = .15]; cTnI, r = -0.107 [P = .32]) and group II (CK-MB, r = -0.202 [P = .19]; cTnI, r = 0.606 [P = .002]), but our analysis did reveal highly significant correlations in group III (CK-MB, r = 0.584 [P = .003]; cTnI, r = 0.605 [P = .002]).
Measuring the plasma concentration of sICAM-1 before the concentrations of cardiac markers increase in patients with MI may provide clinicians with faster and reliable data for deciding on and administering the most appropriate procedures and/or therapies.