Impact of periprocedural creatine kinase-MB isoenzyme release on long-term mortality in contemporary percutaneous coronary intervention.

Objective: To evaluate the incidence of periprocedural creatine kinase-MB (CK-MB) release and its impact on longterm mortality in contemporary percutaneous coronary intervention (PCI) at a tertiary referral center.

Methods: Retrospective analysis of 4,958 patients undergoing PCI with deployment of at least 1 stent at our center between January 1, 2003 and December 31, 2005. Patients admitted with acute ST-elevation myocardial infarction or cardiogenic shock (n = 617), and patients with no available CK-MB levels (n = 477) were excluded, leaving 3,864 patients for analysis. The outcome measure was all-cause mortality obtained from the National Strategic Tracing Service with patients followed up to June 30, 2006 (mean follow up 22 months). The association between CK-MB level and mortality was examined using Cox proportional hazards analysis.

Results: CK-MB elevation above the upper limit of normal (ULN) was detected in 29.4% patients. A total of 127 deaths were observed during follow up. By multivariate analysis, periprocedural CK-MB was independently associated with an increased risk of death (adjusted hazard ratio for every 10 units: 1.09; 95% CI: 1.05-1.12; p < 0.001). The relationship between the level of CK-MB and mortality was further examined by applying strata of CK-MB levels to the multivariate analysis (adjusted hazard ratio: 1.30, 1.76 and 2.26 for CK-MB levels of 1-3, 3-5 and > 5 the ULN, respectively).

Conclusion: In the current era of PCI, periprocedural myonecrosis, evidenced by CK-MB elevation, is common and is associated with less favorable long-term mortality.