OBJECTIVE: To assess the prognostic effect of the changes in the levels of 4 biochemical markers of myocardial damage (CK-MB activity/mass and troponins T and I) after stent implantation in regard to the occurrence of death, infarction, and new myocardial revascularization procedures in a one-year period. The study also aimed at determining the incidence of their elevations and the existence of predictive variables. METHODS: Those 4 markers were measured in 199 patients treated with stent implantation in native arteries in the following 3 periods: before the procedure, 6-8 hours after the procedure, and 14-18 hours after the procedure. Survival curves and Cox logistic regression were used to determine the prognostic impact of the changes on the occurrence of cardiac events in one year. RESULTS: Changes in the levels of the 4 markers after stent implantation are relatively frequent (6.1% to 32.8%), are associated with the degree of complexity of the lesions treated (long lesions and angulations > 45º) and with the development of problems during the procedure (occlusion of the secondary branches, presence of angina, and electrocardiographic changes). The infarction-free survival rate and the need for a new revascularization were significantly lower only in the patients with an elevation in the CK-MB activity after the procedure as compared with those in patients without that alteration (60% x 85.08%; P=0.025). The following variables influenced the event-free survival rate: diabetes mellitus (OR: 2.27; P=0.0256), balloon predilation (OR: 3.16; P=0.0082), and an elevation in the CK-MB activity after the procedure (OR: 3.64; P=0.0162). CONCLUSION: Systematic monitoring of CK-MB activity after coronary stenting is justified due to its clinical and laboratory behavior reported in studies relating its elevation after the procedure to a worse late outcome, and due to its low cost.
stent; biochemical markers; prognosis
