1. Mediastinum Clinical Anatomy PA 544 Tony Serino, Ph.D. Biology Department Misericordia Univ.

2. Mediastinum Anterior Superior Middle Posterior Superior and anterior are continuous with each other; both may be referred to as the superior mediastinum

3. Superior Mediastinum Great Vessels of the Heart Aortic arch Transverse thoracic plane

4. Remnant of Ductus arteriosus Ligamentum arteriosum

5. Usual Aortic Arch Pattern 65% of all people RS BT LS LC RC

6. Aortic Arch Variations 27% one BT with both CC exiting 5% 1.2% two BT left vert. a.

8. SVC BC SVC Vagus Phrenic

9. Pulmonary Arteries and Veins

10. Trachea and Primary bronchi

11. Structure Order BC Aorta PA Trachea

12. Esophagus Function: Deglutition Two sphincters: upper and lower esophageal sphincters (lower is physiological only) Retropleural position (therefore, covered by adventitia) Mucosa: stratified squamous with many mucus glands (esophageal glands) Muscularis: changes from skeletal to smooth muscle

13. Thymus Gland Bilobed organ that is largest in children, but begins to regress sharply at the onset of puberty (around age 11) It is the site of T-cell lymphocyte production and produces hormones (such as, thymosin) that modifies their physiology

14. General Circulatory System 1.Cardiovascular –Consists of a closed system of vessels which transport blood –Two circuits: Systemic and Pulmonary –Arteries move blood away from the heart –Veins move blood toward the heart

15. Heart Development

16. Fetal Circulation

17. Selected Heart Defects

18. Heart as a Dual Pump Cardiac muscle arranged as whorls that squeeze the blood Twin pumps: systemic and pulmonary Four chambers: 2 atria and 2 ventricles

19. Cardiac Muscle Cells

20. Cardiac Muscle Depolarization

21. Heart: Location

22. Heart in Relation to other Organs

23. Layers of the Heart and Pericardium

24. Heart: Anterior View Transverse Pericardial sinus

25. Heart: Posterior View Oblique Pericardial sinus

26. Heart: Internal Anatomy

27. Differences in Ventricular Wall

28. Coronary Artery Schematic (LAD)

29. Most Common Coronary Arterial Pattern Fig. 1.51 Ant. Desc. a. (LAD) Post. Desc. a. R. Marginal a. L. Marginal a. Circumflex a.

30. Coronary Variation 15% LCA dominant Single CA Most people right dominant. Circumflex from right aortic sinus (4% have an accessory coronary artery) (note: which branch gives rise to posterior descending a.determines dominance)

31. Fig. 12.66b

32. Fig. 12.66c

33. Fig. 12.66d

35. Coronary Vein Schematic

36. Coronary Veins Fig. 1.52 Coronary sinus Great Cardiac v. Small Cardiac v.Middle Cardiac v. Ant. Cardiac veins

37. Major Cardiac Valves

38. aortic valve (SL) AV (tricuspid) Heart Valves sinus Nodule (corpara aranti) cusps

39. Diastole: Period of Ventricular Filling

40. Systole: Isovolumetric Contraction

41. Systole: Ventricular Ejection

42. Diastole: Isovolumetric Relaxation

43. Conduction System of Heart

45. ECG and electrical changes

46. Normal ECG

47. ECG Normal Sinus Rhythm Junctional Rhythm (AV node rhythm)

48. Second Degree Heart Block Ventricular Fibrillation (V-fib)

49. Heart Sounds “Lub-dub” Sound associated with valve closing producing turbulent blood flow

50. Heart Rate Control Sinus Rhythm = normal SA node control Autonomic Activity –Sympathetic (thoracic trunk) = accelerator (induces tachycardia) –Parasympathetic (vagus n.)= brake (induces bradycardia) Hormones –epinephrine Drugs -caffeine, nicotine, atropine, etc.

51. Posterior Mediastinum Thoracic aorta Sympathetic trunk Vagus n. Azygous v. Trachea Esophagus Phrenic n. Intercostal a., v., & n. Hemiazygous v. Lung root Thoracic duct

52. Small Aortic Branches Bronchial a. Intercostals Coronary Esophageal

53. Azygous vein Hemiazygous v.

54. Nerves of Post. Mediastinum

55. Thoracic Duct