Troponin I & CK-MB Which is better for detect of perioperative myocardial damage after CABG ??

1. Troponin I & CK-MB Which is better for detect of perioperative myocardial damage after CABG ?? Presented by Ri 陳世洲 Advised by P 柯文哲

2. Ideal cardiac markers • High concentration in cardiac muscle, high sensitivity • Cardiac-specific • Early diagnosis • Concentration related with the size of infarction area • Persists for several hours

3. Ideal cardiac markers • CK (Creatine kinase) • CK-MB • LDH • LD 1 • Myoglobin • Troponin I • Troponin T

4. CK (Creatine kinase) • Muscle, liver, brain, kidney, spleen… • Function: • conversion of creatine to phosphocreatine • consuming adenosine triphosphate (ATP) and generating adenosine diphosphate (ADP). • Isoenzymes of CK • CK-MM: skeletal muscle • CK-MB: cardiac muscle • CK-BB: brain • Very sensitive!! • Restriction: not cardiac-specific

5. CK-MB • Rich in cardiac muscle • Cardiac m.: 70~95% CK-MM / 15~30% CK-MB • Skeletal m.: 97~99% CK-MM / 1~3% CK-MB • Skeletal muscle injury: false positive • CK-MB / total CK > 2.5 % • Restriction: lower cardiac-specific

6. Myoglobin • Accounts for 5~10% cytoplasmic protein in striated muscle • Earliest cardiac marker • Lack of cardiac specificity • Short persistence

7. LDH (Lactate dehydrogenase) • Liver, kidney, cardiac muscle, skeletal muscle, pancreas, spleen, lung…… • Elevated: 12~24 hrs, peak: 2~3 days, decreased: 5~14 days • Normal range: LDH 1: 19 ~ 31 % LDH 2: 30 ~ 39 % LDH 3: 17 ~ 27 % LDH 4: 5 ~ 13 % LDH 5: 6 ~ 13 % LDH 2 > LDH 1 > LDH 3 > LDH 5 > LDH 4 • LDH-1 ￪ : MI, Hemolytic anemia, testicular tumor (LDH-1 > LDH-2: heart injury !!!) LDH-2 ￪ : Pneumonia, CHF, lymphoma LDH-3 ￪ : Lung diseases LDH-4 ￪ : Pancreatitis LDH-5 ￪ : Liver diseases, Intestinal diseases, Muscle disease

8. Troponins • Striated muscle: thick filament, thin filament • Thin filament: • Actin • Troponin • Tropomyosin

9. Troponins • Troponin I: binds Actin, inhibitory function • Troponin T: binds Tropomyosin • Troponin C: 4 Ca+2 binding site • ATPase: myosin head • Cardiac troponin I • AMI late diagnosis • evaluate infarction area • Peri-op MI diagnosis

10. AMI cardiac markers • Myoglobin • CK-MB • Troponin-I

11. Common serum markers used to detect AMI Marker       Initial elevation after AMI Mean time to peak elevation after AMI Time to return to baseline after AMI Myoglobin 1 - 4 h 6 h 18 - 24 h  CK-MB 3 - 12 h 10 - 24 h 48 - 72 h MB-isoforms 1 - 6 h 4 - 12 h 38 h cTnI 3 - 12 h 10 - 24 h 5 - 10 days cTnT  3 - 12 h 12 - 24 h 5 - 14 days

12. Incidence, Predictors, and Significance of Abnormal Cardiac Enzyme Rise in Patients Treated With Bypass Surgery in the Arterial Revascularization Therapies Study (ARTS) Circulation. 2001;104:2689-2693.

14. Frequency of CK-MB elevation after CABG

17. MACEE: Major Adverse Cardiac and Cerebrovascular Events

18. Figure 3. Kaplan-Meier curves illustrating the incidence of death and myocardial infarction (MI) at 1-year follow-up in patients with normal CK-MB levels (dashed gray lines), 1 to 3 times normal (solid gray lines), 3 to 5 times normal (dashed black lines), and 5 times normal (solid black lines) after bypass surgery. The P-value refers to the comparison among the 4 groups.

19. Troponin I, Troponin T, or Creatine Kinase-MB to Detect Perioperative Myocardial Damage After Coronary Artery Bypass Surgery 1998;114;482-486 Chest

25. Comparison indicated by appearance of new Q wave on ECG after CABG

26. Costs • Myoglobin: $ 120 • CK: $ 70 • CK-MB: $ 150 • Troponin-I: $ 450

27. Conclusions Which cardiac enzyme marker is better for our post-CABG protocol ??? Troponin-I : better CK, CK-MB : cheaper

28. Thanks for your listening.