Do we still need CK-MB in coronary artery bypass grafting surgery?
OBJECTIVE
The aim of this study was to evaluate the role of cardiac Troponin I (cTnI) and CK-MB for early prediction of outcome of patients undergoing coronary artery bypass grafting (CABG) surgery.


METHODS
In 134 consecutive patients undergoing CABG-surgery blood samples were analyzed for cTnI concentration and CK-MB activity. ECG, hemodynamic parameters and the need for inotropic support, were continuously registered. Patients were divided into group A (uneventful course), group B (ischemia by ECG, hemodynamic stability) and group C (ischemia by ECG and IABP).


RESULTS
After removal of X-clamp an increase cTnI and CK-MB was observed in all patients. Five hrs after stop of CPB group A (8.3+/-4.2 microg/L) had lower cTnI values compared to group B (14.8+/-5.3 microg/L) (p=0.035) and C (54+/-22.8 microg/L) (p=0.023). The cut off value was 14.8 microg/L. Sensitivity and specificity (99%/97%) was higher for cTnI than for CK-MB (90%/30%). The positive predictive value of outcome was better for cTnI (86%) than for CK-MB (33%).


CONCLUSIONS
CTnI is a specific and sensitive marker for evaluation of perioperative myocardial ischemia (PMI). Additional determination of CK-MB activity does not provide further clinical information. CTnI should be the marker of first choice in CABG surgery.
Bimmel
D
D
Department of Cardiac Surgery, University of Bonn, Bonn, Germany. dieter.bimmel@ukb.uni-bonn.de
Patermann
B
B
Schlosser
T
T
Winkler
K
K
Tiemann
K
K
Likungu
J A
JA
Preusse
C J
CJ
Welz
A
A
D000368:Aged; D015415:Biomarkers / Q000097:blood; D001026:Coronary Artery Bypass; D003402:Creatine Kinase / Q000097:blood*; D052279:Creatine Kinase, MB Form; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood*; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis*; D011184:Postoperative Period; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D007527:Isoenzymes; D019210:Troponin I; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form