Cardiac Troponin T and CK-MB Mass Release After Visually Successful Percutaneous Transluminal Coronary Angioplasty in Stable Angina Pectoris

The incidence of cardiac troponin T (Tn-T) and creatine kinase (CK) isoenzyme MB mass release was studied in 23 patients with stable angina pectoris undergoing visually successful percutaneous transluminal coronary angioplasty (PTCA). Serial blood samples were drawn for measurement of serum Tn-T, CK-MB mass, total CK activity, CK-MB activity, and lactate dehydrogenase isoenzyme (LD-1). ST segment monitoring was carried out during PTCA and for the following 24 hours. None of the patients showed electrocardiographic (ECG) evidence of myocardial infarction. However, Tn-T was elevated in three patients (0.23 to 1.32 micrograms/L), and in these three and an additional three patients CK-MB mass was also elevated (7.0 to 27.5 micrograms/L). Total CK activity and LD-1 were only elevated in one of these six patients. None had elevated CK-MB activity. ST segment depression on ECG recording was not predictive of Tn-T or CK-MB mass release. Patients with elevated Tn-T or CK-MB mass did not differ with respect to demographic data, stenosis characteristics, or in the PTCA procedure. We conclude that CK-MB mass uncovers clinically and ambulatory electrocardiographically inapparent severe myocardial ischemia/minor myocardial damage (microembolization) in 26% (6 of 23) of patients after visually successful PTCA; 13% (3 of 23) had elevated Tn-T, indicating minor myocardial damage. The application of these markers in the future could be of considerable value for determining the efficacy of coronary angioplasty and atherectomy, as well as for drug therapy in connection with such procedures.