Frequency and long-term impact of myonecrosis after coronary stenting

AIMS: To study the frequency of creatine kinase MB elevation in stent recipients and to correlate the magnitude of myonecrosis with long-term ischaemic events. METHODS AND RESULTS: We evaluated the frequency and impact (major adverse ischaemic events) of creatine kinase MB elevation in 3478 patients undergoing planned coronary stenting and divided them in five strata according to peak creatine kinase MB: normal, 1-3 x, 3-5 x, 5-10 x and >10 x above upper limit of normal. Graft intervention was done in 15% and 61% received platelet glycoprotein IIb/IIIa receptor inhibitors. The average follow-up period was 15+/-15 (range 1-72) months. Creatine kinase MB elevation above upper limit of normal occurred in 24% and in 5.3% it was greater than 5 x upper limit of normal. The unadjusted rates of actuarial mortality in the five strata were: 7.5% (198/2637), 8.0% (40/502), 11.0% (17/155), 10.8% (11/102) and 29.3% (24/82), respectively, P<0.001. Logistic regression analysis including 18 demographic and procedural variables revealed that, in addition to age, extent of coronary disease, ventricular function and coronary risk profile, creatine kinase MB elevation was associated with a significant increase in major ischaemic events at follow-up. The excess risk was concentrated mainly in the highest stratum of creatine kinase MB elevation. CONCLUSIONS: Thus, in the era of stenting and aggressive adjunctive pharmacology, peri-procedural myonecrosis still remains frequent and has an important impact on long-term event-free survival. Intensive efforts to reduce creatine kinase MB elevation after revascularization are warranted and should lead to important benefits.