Death Following Creatine Kinase-MB Elevation After Coronary Intervention: Identification of an Early Risk Period: Importance of Creatine Kinase-MB Level, Completeness of Revascularization, Ventricular Function, and Probable Benefit of Statin Therapy

Abstract

Background—Creatine kinase (CK)-MB elevation after percutaneous coronary intervention (PCI) has been associated with subsequent cardiac death. The patients at risk, the timing of risk, and potential treatment implications are uncertain. Methods and Results—Eight thousand, four hundred nine consecutive non– acute myocardial infarction patients with successful PCI and no emergency surgery or Q-wave myocardial infarction were followed for 38±25 months; 1446 (17.2%) had post-PCI CK-MB above normal on routine ascertainment. Patients were prospectively stratified into those with CK-MB 1 to 5× or CK-MB >5× normal. No patient with CK-MB 1 to 5× normal died during the first week after PCI, and excess risk of early death for patients with CK-MB elevation occurred primarily in the first 3 to 4 months. The actuarial 4-month risk of death was 8.9%, 1.9%, and 1.2% for patients with CK-MB >5×, CK-MB 1 to 5×, and CK-MB ≤1× normal (P <0.001). Death within 4 months was independently correlated with the degree of CK-MB elevation, creatinine ≥2 mg%, post-PCI C-reactive protein, low ejection fraction, age, and congestive heart failure class (P <0.01 for all). In a matched subset analysis, incomplete revascularization (P <0.001), congestive heart failure class (P =0.005), and no statin treatment at hospital discharge (P =0.009) were associated with death. Conclusions—Patients with CK-MB elevation after PCI are at excess risk of death for 3 to 4 months, although prolonging hospitalization for CK-MB 1 to 5× is unlikely to modify risk. CK-MB >5× normal, incomplete revascularization, elevated C-reactive protein, heart failure, the elderly, and hospital discharge without on statin therapy increases risk. Several of these factors suggest that inflammation may play a part in the excess risk of death.