Creatine kinase-MB assessed in patients with acute myocardial infarction correlates with cardiac magnetic resonance infarct size at 6-month follow up.

Introduction: There are still only limited data concerning the use of creatine kinase-MB (CKMB) values for predicting infarct size in long-term follow up in patients with ST-segment elevation myocardial infarction (STEMI) who have undergone primary percutaneous coronary intervention (PCI). The aim of this study was to analyze the correlation between CKMB and both infarct size and left ventricular function during a 6-month follow up.
Methods: In a cohort of 68 patients with STEMI treated with PCI, serial CKMB assessment was performed at baseline and at 6, 12, 18, 24 and 48 hours after PCI. The area under the curve (AUC) of CKMB was calculated. Cardiac magnetic resonance (CMR) parameters were assessed at 6 months.
Results: All CKMB single time-point values, AUC CKMB, and CKMB maximal value after primary PCI were correlated with CMR infarct size and left ventricular function, but a high correlation (r>0.7) was found only for CKMB at 6 hours, CKMB at 12 hours, CKMB AUC, CKMB maximal value, and CMR infarct size (r=0.71, r=0.73, r=0.72, r=0.75, respectively, p<0.001 for all).
Conclusions: CKMB assessment is a good predictor of infarct size at 6 months in patients with STEMI treated with PCI. The CKMB value at a single time point 12 hours after PCI is a good predictor of infarct size at 6 months, comparable to serial assessment parameters such as AUC CKMB and CKMB maximal value.