1. Exercise 35
Anatomy of the Heart

2. Gross anatomy of the heart
Localized in the mediastinum
It has a pointed apex
At the level of the 5th intercostal space
And a broad base
Beneath the 2nd rib
Is the site of emerging of the great vessels

3. The pericardium Pericardial cavity Visceral pericardium or epicardium
Parietal pericardium
Pericardial fluid
Pericardial sac (fibrous)
Stabilizes the heart and its vessels
Pericarditis

4. The Location of the Heart in the Thoracic Cavity
Figure 20.2c

5. Gross anatomy of the heart
Myocardium
Muscle wall of the heart
Fibrous skeleton of the heart
Endocardium

6. Superficial Anatomy of the Heart
The heart consists of four chambers
Two atria
Two auricles
Two ventricles
Major blood vessels of the heart include
Inferior and superior vena cavae
Aorta, pulmonary trunk and pulmonary veins

7. The Superficial Anatomy of the Heart

8. The Superficial Anatomy of the Heart
Figure 20.3b, c

9. The superficial Anatomy of the heart
Atria
Thin walled upper chambers that receive blood from the vena cava
Ventricles
Thick walled lower chambers separated from the atria by AV valves

10. External anatomy of the heart and blood flow
Right atrium (RA)
Receives blood coming from the body via superior, inferior vena cava and coronary sinus
auricle
Right ventricle (RV)
Receives blood from the RA and pumps it into the pulmonary trunk
Pulmonary trunk
Left and right pulmonary arteries

11. External anatomy of the heart and blood flow
Lungs
Pulmonary veins
2 rights and 2 lefts
Left atrium (LA)
Receives blood from the pulmonary veins
Auricle

12. External anatomy of the heart and blood flow
Left ventricle (LV)
Pumps blood into the aorta
Aorta
Ascending, arch, descending
Ligamentum arteriosum
Remnant of the ductus arteriosus
Between pulmonary artery and aorta

13. Blood supply to the heart
Coronary arteries
Right
Posterior interventricular artery
Marginal
Supplies posterior part of the ventricles and lateral part of the right heart

14. Blood supply to the heart
Left coronary
Anterior interventricular artery
Circumflex
Supplies the anterior part of the ventricles and laterodorsal part of the heart

15. Blood Supply to the Heart - veins
Veins that empty into the coronary sinus
Great cardiac vein, posterior cardiac vein, middle cardiac vein, small cardiac vein
Anterior cardiac veins empty into the RA.

16. Coronary Circulation
Figure 20.9a, b

17. The Sectional Anatomy of the Heart

18. Internal anatomy of the heart
Right atrium
Fossa ovalis
Foramen ovale
Openings of the superior and inferior vena cavas
Pectinate muscle
SA and AV nodes
Interatrial septum
Wall between atria

19. Internal anatomy of the heart
Right ventricle
Tricuspid valve
Chordae tedineae
Papillary muscles
Trabeculae carneae – muscular ridges
Interventricular septum
Wall between ventricles

20. Internal anatomy of the heart
Moderator band (septomarginal band)
Horizontal muscular ridge
Brings the impulse to the papillary muscles
Only present in the RV
Conus arteriosus
Conical pouch from which the pulmonary artery arises

21. Internal anatomy of the heart
Left atrium
Principal cavity (sinus)
Pectinate muscles on the auricle only
Openings of the pulmonary veins

22. Internal anatomy of the heart
Left ventricle
Bicuspid valve
Trabeculae carneae
Papillary muscles
Chordae tendineae

23. Valves of the Heart
Figure 20.8a

24. Valves of the Heart
Figure 20.8b

25. Valves of the heart Bicuspid or mitral or left AV
Tricuspid or right AV
Aortic semilunar
Pulmonary semilunar

26. The intrinsic conducting system
Functional syncytium
Gap junctions

27. The intrinsic conducting system

28. The intrinsic conducting system
Controlling system over the heart
Autonomic nervous system
Sympathetic
Parasympathetic
Intrinsic conducting system or nodal system
Specialized myocardial tissue
Initiates the heart beat

29. The Intrinsic Conducting System
The conducting system includes:
Sinoatrial (SA) node ( bpm)
Contain the pacemaker cells
Located in the right atrium
Atrioventricular (AV) node (40-60 bpm)
Located in the atrium septum at the junction of the atria and ventricles

30. The Intrinsic Conducting System
AV bundle or bundle of His
Located in the interventricular septum
Right and Left bundle branches
Purkinje fibers
Located in the myocardium
Larger in the left ventricle

31. Steps for the heart beat
SA node begins the action potential
Stimulus spreads across the atria
Stimulus spreads to the AV node
Atrial contraction
Impulse then travels through the AV bundle
Impulse reaches right and left bundle branches

32. Steps for the heart beat
Then it reaches the Purkinje fibers
Impulse reaches the papillary muscles (via moderator band on the right side)
Impulse is spread to the ventricles
Ventricular contraction

33. The Intrinsic Conducting System

34. Pulmonary and systemic circulation

35. Pulmonary circulation
Pulmonary arteries
Leave the RV
Carry blood rich in CO2
Blood flows to the lungs
Pulmonary veins
Leave the lung
Blood rich in O2
Blood flows to the LA

36. Systemic circulation Aorta Leaves the LV Blood rich in O2
Blood flows to the body
Vena cava
Superior brings blood from head, neck, arms and superior trunk
Inferior brings blood from the rest of the body
Blood rich in CO2
Blood flows to the RA

37. Microscopic anatomy of the heart
Involuntary
Cardiac cells
Intercalated discs
Branching
Central nucleus
Striations

38. Identify these structure on the fresh heartRA
Auricle
Pectinate muscles
Superior and inferior vena cavas
Coronary sinus
Tricuspid valve

39. Identify these structure on the fresh heartRV
Papillary muscles
Chrodae tendineae
Trabeculi carneae
Moderator band
Pulmonary trunk and its semilunar valve

40. Identify these structure on the fresh heartLA
Auricle
Pectinate muscles

41. Identify these structure on the fresh heartLV
Myocardium
Papillary muscles
Chordae tendineae
Mitral valve
Trabeculi carneae
Interventricular septum
Aorta and its semilunar valve
Coronary arteries