Myocardial injury after apparently successful coronary stenting with or without balloon dilation: direct versus conventional stenting.

Direct stenting (i.e., stenting without balloon predilation) is a novel approach to the percutaneous treatment of coronary artery lesions. This approach, by reducing aggression to the vessel wall and immediately sealing the dissections created by balloon inflation by the endoprosthesis, may also significantly lower the rate of procedural ischemic complications. Our purpose was to measure cardiac troponin T (cTnT), creatine kinase and its isoform CKMB after apparently successful elective stent implantation with conventional stenting (CS) or direct stenting (DS) and to compare the procedural myocardial injury between these 2 approaches. Enzyme levels were measured before and 16 hours post-procedure. A second-generation commercial ELISA cTnT assay (Boehringer Mannheim Corporation) was used to measure cTnT with a cut-off of 0.1 ng/dl. There was no abnormality in any of the 3 enzymes in either group before the procedure. Although the incidence of cTnT was elevated in 4 of 37 patients (10.8%) in the DS group and in 5 out of 23 patients (21.7%) in the CS group at 16 hours post-procedure, these values did not reach statistical significance (p > 0.05). Creatine kinase and CKMB levels were not elevated in any of the patients. CTnT and CKMB measurements are needed to detect this minor myocardial damage. Randomized studies with larger patient populations should be conducted to compare the two different approaches.