Creatine kinase-MB enzyme elevation and long-term clinical events after successful coronary stenting in lesions with ruptured plaque.

Patients with acute coronary syndrome are at increased risk of acute and long-term events after stent implantation. We compared the impact of intravascular ultrasound detected plaque rupture on creatine kinase-MB (CK-MB) isoenzyme release and clinical outcomes by comparing 62 patients with ruptured plaques with 62 matched control patients who underwent stent implantation. Two thirds of the patients in each group presented with an acute coronary syndrome. There were no differences in procedural complications between groups, although patients with ruptured plaque had higher CK-MB elevation rates than those without ruptured plaque (1 to 3 times the upper limit of normal CK-MB, 35% vs 10%, p <0.001; >3 times the upper limit, 15% vs 2%, p = 0.02). Independent predictors of CK-MB elevation were presence of ruptured plaque (p = 0.03) and unstable angina (p = 0.04). Patients with ruptured plaque had higher composite rates of late events (target lesion revascularizations/myocardial infarctions/cardiac deaths) than controls (25% vs 9%, p = 0.03). These results were similar when only patients with acute coronary syndrome were studied. Plaque rupture morphology is associated with higher periprocedural CK-MB release and worse 1-year clinical outcome in patients treated with coronary stenting.