Effects of transvenous pacing on cardiac troponin release

Abstract

Cardiac troponins are invaluable tools for the detection of minimal myocardial injury. No study to date has analyzed the effect of permanent cardiac pacing on minimal myocardial injury detection by cardiac troponin I (cTnI) measurement. We investigated 76 clinically stable patients (mean age 75 years, range 31-93 years, 59% men) listed for elective endocardial permanent pacemaker insertion. Patients were required to have normal levels of cardiac cTnI, aspartate transaminase (AST) and creatinine kinase (CK) on a venous blood sample taken immediately prior to elective pacemaker implantation. Repeat measurements of AST, CK, and cTnI were performed at a mean of 19.2 post implantation. There was a detectable small rise in cTnI levels above normal in 21% of patients in a second blood sample taken 18-21 hours later (mean cTnI 0.39 +/- 0.37 microg/L, normal < 0.15 microg/L). The only factor that correlated with this rise was prolonged x ray screening time for lead implantation.