Myocardial injury after off-pump coronary artery bypass grafting operation.
OBJECTIVE
Perioperative myocardial ischemia is less pronounced in off-pump coronary artery bypass (OPCAB) compared to on-pump coronary artery bypass; however, the threshold over which the postoperative release of cardiac troponin I (cTnI) release and creatine kinase-MB (CK-MB) after OPCAB should be considered clinically relevant is unknown. The study was designated to evaluate if perioperative myocardial damage, measured by means of postoperative release of cTnI and CK-MB, has an influence on short- and mid-term outcome after OPCAB operations.


METHODS
Two hundred and sixty-one unselected patients undergoing OPCAB had cTnI and CK-MB measured preoperatively and nine times postoperatively. Postoperative peak values were evaluated and the 80th percentiles were used to segregate the population into two groups for each marker. The following cut-offs were used: 7.1 ng/dl for cTnI peak and 36.3 ng/dl for CK-MB peak.


RESULTS
Patients with cTnI>7.1 ng/ml (n=51) and CK-MB>36.3 ng/ml (n=48) had a longer mechanical ventilation and ICU length of stay. Nevertheless, hospital mortality did not differ between groups. Survival after 3 years was 92.8+/-2.3% and 81.8+/-6.2 for patients with postoperative cTnI peak<or=7.1 ng/ml and >7.1 ng/ml, respectively (p=0.003). It was 93+/-2.2% and 80+/-6.8% for patients with CK-MB<or=36.3 ng/ml and >36.3 ng/ml, respectively (p=0.005). Adjusted hazard ratios for mid-term mortality were HR 2.7 (CI 1-7.6), p=0.05 for cTnI>7.1 ng/dl and HR 3.1 (CI 1-9.1), p=0.04 for CK-MB>36.3 ng/ml.


CONCLUSIONS
Perioperative myocardial damage should not be considered an innocuous event following OPCAB operations since the survival rate over 3 years is significantly worse in patients with the highest postoperative peak release of cTnI and CK-MB.
Paparella
Domenico
D
Division of Cardiac Surgery, Department of Emergency and Organ Transplant, University of Bari, Italy. dpaparella@cardiochir.uniba.it
Cappabianca
Giangiuseppe
G
Malvindi
Piergiorgio
P
Paramythiotis
Andreas
A
Galeone
Antonella
A
Veneziani
Nicola
N
Fondacone
Corrado
C
de Luca Tupputi Schinosa
Luigi
L
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects* / Q000401:mortality; D052279:Creatine Kinase, MB Form / Q000097:blood*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D017202:Myocardial Ischemia / Q000097:blood / Q000209:etiology*; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I; D052279:Creatine Kinase, MB Form