PROGNOSTIC IMPLICATION OF CREATINE-KINASE ELEVATION FOLLOWING ELECTIVE CORONARY-ARTERY INTERVENTIONS

Objective.-To determine the prognostic significance of creatine kinase (CK) elevation following elective percutaneous transluminal coronary angioplasty (PTCA). Design.-Retrospective cohort study, Setting.-Terti ary care referral center. Subjects.-A total of 253 consecutive patient s with total CK and CK-MB fraction (CK-MB) elevation (case patients) a nd 120 patients without CK elevation (controls). Control patients had undergone interventions during the same month and year using the same devices. Main Outcome Measures.-In-hospital and late cardiac mortality , subsequent myocardial infarction, and the combined end point of card iac mortality or myocardial infarction. Results.-Patient groups were s imilar with respect to age, sex, extent of coronary artery disease, le ft ventricular function, number of lesions treated by PTCA, and mean d uration of follow-up (>3.5 years). Cardiac mortality was significantly greater (P=.02) for patients with CK elevation after PTCA, When patie nts were categorized according to peak CK elevation, cardiac mortality differed significantly among patient groups (P=.007), with increased cardiac mortality observed for patients with high (>3,0 times normal) and intermediate (1,5 to 3.0 times normal) CK elevations. In multivari ate analyses, higher peak CK and lower ejection fraction were the most important predictors of increased cardiac mortality (both, P<.001); t he relative risk for cardiac mortality was 1.05 (95% confidence interv al, 1.03-1.08) per 100-U/L increment increase in CK. Conclusions.-Crea tine kinase elevation following elective PTCA is associated with incre ased late cardiac mortality. This increase in cardiac mortality is ind ependent of clinical variables, severity of heart disease, coronary ar tery lesion characteristics, interventional devices, and procedural ou tcomes. Even patients with lesser degrees of CK elevation are at signi ficantly increased risk for late cardiac death.