Echocardiography

1. Echocardiography Ischemic Heart Disease

2. Ischemic Heart Disease One of the most common indication for echocardiography is evaluation of patients with suspected or documented coronary artery disease.

3. Ischemic Heart Disease Echocardiography focuses on the outcome of coronary artery disease. • Systolic wall thickening • Endocardial motion

4. Ischemic Heart Disease Echocardiography offers • Detailed function assessment of segmental and global LV systolic function both at rest and after interventions to induce ischemia.

5. Ischemic Heart Disease Coronary Artery • LMCA arises from the superior aspect of the left coronary sinus of Valsalva and divides into 1. LAD artery 2. Circumflex artery

6. Ischemic Heart Disease LAD Extends via the interventricular groove down the anterior wall to and sometimes around the LV apex.

7. Ischemic Heart Disease Circumflex Coronary • Passes laterally in the atrioventricular groove.

8. Ischemic Heart Disease RCA • Arises from the superior aspect of the right coronary sinus of Valsalva. • Extends inferomedially following the interventricular groove.

9. Ischemic Heart Disease Right Dominant Coronary Circulation • 80% • RCA gives rise to the posterior descending artery which lies in the inferior interventricular groove.

10. Ischemic Heart Disease Left Dominant Coronary Circulation • 20% • Circumflex artery gives rise to the posterior descending artery.

11. Coronary Artery

12. Coronary Artery

13. Coronary Artery

14. Ischemic Heart Disease

15. Ischemic Heart Disease Segments From base to apex the LV is divided into three segments. • Basal • Mid-ventricular • Apical These correspond to proximal, middle and apical lesions of the coronary artery.

16. Ischemic Heart Disease Basal Mid-ventricular Apical

17. Ischemic Heart Disease In the short axis view at the base (MV), the LV is divided into: • Anterior wall • Lateral wall • Posterior wall • Inferior wall • Interior septal wall • Anterior septal wall

18. Ischemic Heart Disease In the short axis view at the mid-left ventricle (the papillary muscle level), the LV is divided into: • Anterior wall • Lateral wall • Posterior wall • Inferior wall • Interior septal wall • Anterior septal wall

19. Ischemic Heart Disease In the short axis view at the apex the LV is divided into: • Anterior wall • Postero-lateral wall • Inferior wall

20. Ischemic Heart Disease

21. Ischemic Heart Disease

22. Ischemic Heart Disease

23. Ischemic Heart Disease

24. Ischemic Heart Disease Irreversible myocardial damage results in wall motion abnormalities that are present at rest.

25. Ischemic Heart Disease Acute Infarction • Normal wall thickness • Reduced or absent systolic thickening • Reduced or absent endocardial motion

26. Ischemic Heart Disease Old Myocardial Infarction • Thinning of the affected segment • Increased echogenicity of the affected segment. • Abnormal wall motion • Absent systolic wall thickening

27. Ischemic Heart Disease Myocardial Ischemia • Reversible imbalance in myocardial oxygen demand/supply ratio. • Blood flow is adequate for myocardial oxygen demand at rest. • Blood flow becomes inadequate to meet increased myocardial demands(> 70% stenosis).

28. Ischemic Heart Disease Causes of Increased oxygen demands • Exercise • Pharmacologic interventions • Mental stress

29. Ischemic Heart Disease Patients with coronary artery disease with no prior myocardial infarction has normal wall motion.

30. Ischemic Heart Disease Sequence of events in Myocardial Ischemia • Biochemical changes. • Perfusion defect (radionuclide techniques). • Diastolic dysfunction (impaired relaxation and reduced compliance).

31. Ischemic Heart Disease Sequence of events in Myocardial Ischemia • Systolic dysfunction (decreased systolic thickening and endocardial motion). • ECG changes (ST segment depression). • Angina.

32. Ischemic Heart Disease Global LV Systolic Function • Qualitatively • Quantitatively

33. Ischemic Heart Disease Segmental LV Systolic Function • Semi-quantitative scoring system • Each myocardial segment is assessed for endocardial motion and given a score. • The wall motion score index is calculated.

34. Ischemic Heart Disease

35. Ischemic Heart Disease Hyperkinesis • Increased endocardial inward motion and wall thickening in systole.

36. Ischemic Heart Disease Normal • Normal endocardial inward motion and wall thickening in systole.

37. Ischemic Heart Disease Hypokinesis • Reduced endocardial inward motion and wall thickening in systole.

38. Ischemic Heart Disease Akinesis • Absence of endocardial inward motion or wall thickening in systole.

39. Ischemic Heart Disease Dyskinesis • Outward motion (bulging) of the segment in systole, usually associated with thin, scarred myocardium.

40. Ischemic Heart Disease Wall motion score index = Sum of individual segment scores Number of segments visualized

41. Ischemic Heart Disease Stress Echocardiography Inducing ischemia during echocardiographic imaging. • Exercise • Pharmacologic

42. Ischemic Heart Disease Exercise • Treadmill • Upright bicycle • Supine bicycle

43. Ischemic Heart Disease Pharmacologic • Dobutamine • Dipyridamole

44. Ischemic Heart Disease

45. Ischemic Heart Disease Treadmill Exercise Protocol • Acquisition of resting images – Baseline Images • Exercise Protocol • Repeat Image acquisition after exercise – Stress Images. • Compare baseline and stress images

46. Ischemic Heart Disease Monitoring • 12-lead EKG • Blood pressure • Symptoms

47. Ischemic Heart Disease Dobutamine Stress Echocardiography Dobutamine • Increases heart rate. • Increases contractility.

48. Ischemic Heart Disease Dobutamine Stress Echocardiography • Start infusion at low dose • Increase dose incrementally every 3 to 5 minute with a calibrated infusion pump until the maximum dose or an endpoint is reached.

49. Ischemic Heart Disease • Atropine is added, if needed to achieve an appropriate increase in heart rate (85% of the patient’s maximum predicted heart rate).

50. Ischemic Heart Disease Patient Monitoring • Periodic BP • Continuous ECG rhythm monitoring • Observation of clinical signs and symptoms