Diagnostic Accuracy of Post Procedural Creatine Kinase, MB Form can Predict Long-Term Outcomes in Patients Undergoing Selective Percutaneous Coronary Intervention?

BACKGROUND: Measuring cardiac markers in blood has been the main strategy for the diagnosis of acute myocardial infarction for nearly 50 years. Creatine kinase-MB (CK-MB) has been demonstrated to be a highly specific marker. OBJECTIVES: The present study aimed to assess the role of CK-MB changes following percutaneous coronary intervention (PCI) to predict one year outcomes of this procedure. PATIENTS AND METHODS: This cohort study was conducted on 138 patients diagnosed with coronary artery disease who underwent PCI. Sixty-nine patients who had a CK-MB elevation ≥ 3 times upper limit of normal (ULN) post procedurally were considered as group I and 69 patients without cardiac enzyme rise after PCI were considered as the control group (group II). The composite end point of major adverse cardiac events (MACE) during one year was assessed by telephone follow-up or presentation at clinical visiting, and compared between the two groups. The MACE was defined as the appearance of at least one of the following events: mortality, repeated revascularization procedures, myocardial infarction, or cerebrovascular events. RESULTS: Although one year mortality in the group I was 4 (5.8%), about two times greater than the other group 2 (2.9%), the difference was not significantly discrepant (P = 0.57). Moreover, 8 (11.6%) of patients in group I experienced one year MACE, while this rate in the other group was 4 (5.8%), with insignificant difference (P = 0.22). In group I, one case experienced coronary artery bypass surgery, one, exhibited cerebrovascular disease and one reported ST segment elevation myocardial infarction (STEMI), while two patients in the other group were suspicious of having non-ST segment elevation myocardial infarction (NSTEMI) and candidates for repeated PCI. Multivariate analysis revealed that increased post-procedural CK-MB ≥ 3 times UNL could not predict long-term MACE in patients who underwent selective PCI. Area under the curve (AUC) for predicting one year MACE was 0.593 (95% CI: 0.397 - 0.788), indicating inappropriate accuracy for this biomarker (P = 0.290). CONCLUSIONS: It seems that CK-MB ≥ 3 times ULN within 24 hours after PCI cannot independently predict one year MACE in patients undergoing PCI.