LABORATORY EVALUATION OF THEROSCLEROSIS AND ACUTE CORONARY SYNDROME

1. LABORATORY EVALUATION OF THEROSCLEROSIS AND ACUTE CORONARY SYNDROME R. Mohammadi Biochemist (Ph.D.) Faculty member of Medical Faculty

2. CORONARY HEART DISEASE

3. CORONARY ARTERY OBSTRUCTION

4. MAIN COMPONENTS OFVASCULAR WALL

5. INTIMAL THICKENING

6. MAJOR COMPONENETS OF ATHEROMATOUS PLAQUE

7. PATHOGENESIS OF ATHERSCLEROSIS

10. CELLULAR EVENTS & CELLULAR INTERACTIONS

11. RISK FACTORS FOR CHD • Clinical Risk Factors • Laboratory Risk Factors

12. CLINICAL RISK FACTORS

13. LABORATORY RISK FACTORS • Common Lipid Markers Including TC, HDL-C, LDL-C & TG • Uncommon Lipid Markers Including Lp(a), beta-VLDL, Apo A-I & Apo B-100 • Nonlipid Markers Including Homocysteine & hsCRP

14. Analytical Error Physiologic Variation Fasting Diseases Drugs Posture Venous vs. Capilary Samples Plasma vs. Serum Storage SOURCES OF RESULT VARIABILITY IN LIPID MEASURMENT

15. ANALYTICAL ERROR • %Total Error = % Bias + 1.96 (%CV)

16. BIOLOGICAL VARIATIONS • Due to Age, Gender, Diet, Season

17. FASTING • Fasting for at Least 9 Hours Is Necessary for TG • Fasting Is Not Necessary for TC • Slight Decrease of LDL-C & HDL-C After Eating

18. Myocardial Infarction Shock Trauma Surgery Weight lose Fever Thyroid Disease Liver Disease Kidney Disease DIEASES

19. DRUGS • Oral Contraceptive Increases VLDL • Anabolic steroids Increase VLDL & Decrease HDL

20. POSTURE & OCCLUSION • TG, TC & Lipoproteins Increase in Standing Position • Prolonged Venous Occlusion Has Similar Effect

21. Venous vs. Capilary • Measurements in Capilary Blood Sample Seem to Be a Little Lower Than Venous Sample

22. PLASMA vs SERUM • Serum & Plasma Can be Used • Plasma Is Preferred for Electrophoresis & Ultracentrifugation • EDTA Is Preferred, But the Results Are Lower • Heparin Can Also Be Used • Protein Aggregation Occurs In Plasma

23. STORAGE • It Is Recommended to Analyze at Day of Sample Collection • Samples Can Be Stored in Refrigerator or Freezer

24. ANALYTICAL APPROACHIN LIPIDS ABNORMALITIES 1) LIPIDS DETERMINATIONS 2) LIPOPROTEIN ANALYSIS

25. LIPIDS DETERMINATION • Cholesterols • Triglycerides • Phospholipids • Free Fatty Acids (FFAs) • Total Serum Lipids

26. CHOLESTEROL DETERMINATIOM Chemical • Liberman-Burchard • Schoenheimer-Sperry • Abell-Kendal

27. CHOLESTEROL DETERMINATIOM • Enzymatic Cholesteryl Ester Cholesterol + FFA Cholesterol + O2 Oixidized Cholesterol + H2O2 H2O2 + Chromogen Colored Complex + H2O Choesteryl Esterase Choesterol Oxidase Peroxidase

28. CHOLESTEROL DETERMINATIOM Sample • Fasting Is Not Necessary • Effect of Posture & Venous Stasis • Variation in Body • Stable for 4 d, 3 m, and Some years at 4oC, -20oC and -70oC Respectively

29. TRIGLYCERIDE DETERMINATION Chemical • Extraction • Hydrolysis • Glycerol Determination

30. TRIGLYCEROIDE DETERMINATIOM • Enzymatic Triglyceride Glycerol + FFA Glycerol + ATP Glycerol 3-p + ADP UV Spectrophotometry Glycerol 3-p + NAD+ DHAP + NADH Colorimetry Glycerol 3-p + O2 DHAP + H2O2 H2O2 + Chromogen Colored Complex + H2O Lpiase Glycerol kinase Glycerol phosphate Dehydrogenase Glycerol phosphate Oxidase Peroxidase

31. TRIGLYCERIDE DETERMINATION Interference by • Glucose • Phospholipids • Glycerol • Oxidants & Reductants

32. TRIGLYCERIDE DETERMINATION Specimen • Fasting Is Necessary • Affected by Posture & Venous Stasis • Oxidants & Reductants • Testing in the Same Day • If Necessary, Storage at 4oC for a few days, -20oC for 3 m and -70oC for Years

33. LIPOPROTEIN ANALYSIS • Ultracentrifuge • Electrophoresis • Serum Appearance • Precipitation Methods • Calculation • Apolipoprotein Derermination

35. MAIN LIPOPROTEINS • CHYLOMICRON • VERY LOW DENSITY LIPOPROTEINS (VLDL) • LOW DENSITY LIPOPROTEINS (LDL) • HIGH DENSITY LIPOPROTEINS (HDL)

36. MAJOR LIPOPROTEINS

38. SERUM APPEARANCE • Increased Chylomcron Turbidity, Creamy Layer • Increased VLDL Turbidity • Increased LDL Clear • Increased HDL Clear

39. REVIEW OF LIPOPROTEIN METABOLISM

40. APOLIPOPROTEINS DETERMINATION • Apo AI • Apo B • Apo CII

41. HDL-C DETERMINATION • Precipitation of Apo B Containing Lipoproteins (VLDL, IDL, LDL) by • Polyanions & Bivalent Cations Heparine Sulfate & Mn2+ Dextran Sulfate & Mg2+ Sodium Tungstate & Mg2+

43. LDL-C DETERMINATION • Ultracentrifugation • Immunochemical • Calculation with Friedwald Equation Total-C = HDL-C + LDL-C + VLDL-C LDL-C = Total-C (HDL-C + ) TG 5

44. CRITERIA FOR DIAGNOSIS OF AMI • Chest Pain • Electrocardiogram (ECG) • Cardiac Markers Diagnosis Requires at Least Two of These Criteria

45. Diagnostic Specificity of ECG Is about 100% • But Its Diagnostic Sensitivity Is 63-82%

46. FEATURES OF AN IDEAL CARDIAC MARKERS They Should • Be Heart Specific • Be Highly Sensitive for Cardiac Damage • Undetectable in Patients without Myocardial Damage • Be Able to Differentiate Reversible from Irreversible Damage • Allow The Monitoring of Reperfusion • Be Able to Estimate Infarct Size And Prognosis • Easy to Use And Cost Effective

47. CARDIAC MARKERS • Cardiac Enzymes 1) CRATINE KINASE (CK) 2) LACTATE DEHYDROGENASE (LD) 3) ASPARTATE TRANSAMINASE (AST) • Cardiac proteins 1) MYOGLOBIN 2) TROPONIN • New Research Markers 1) GLYCOGEN PHOSPHORYLASE 2) HEART FATTY ACID BINDING PROTEIN 3) ISCHEMIA MODIFIED ALBUMIN 4) CARBONIC ANHYDRASE III

49. CREATINE KINASE (CK) • It Is A Dimer Comprising two Subunit 1) B Subunit (Brain Form) 2) M Subunit (Muscle Form) • IT Has Three Isoenzyme: 1) CK-BB (CK-1) from Brain Is Specific for Brain 2) CK-MB (CK-2) from Cardiac Muscle Is The Most Specific for Heart 3) CK-MM (CK-3) from Muscle Has Low Tissue Specificiy

50. TOTAL CK • After Onset of chest Pain 1) It Increases within Few Hours 2) Peaks within 24 h 3) Return to Normal Levels within 48 to 72 h • It Is Not Specific