anatomy applied heart artery vein capillary

1. Professor Md.Toufiqur
Rahman
MBBS, FCPS, MD, FACC, FESC, FRCP, FSCAI,
FCCP,FAPSC, FAPSIC, FAHA,FACP,FASE
Professor and Head of Cardiology
Colonel Malek Medical College , Manikganj
.drtoufiq19711@yahoo.com
Anatomy of
Cardiovascular System

2. The Cardiovascular System
• A closed system of the heart and blood
vessels
– The heart pumps blood
– Blood vessels allow blood to circulate to all
parts of the body
• The function of the cardiovascular system
is to deliver oxygen and nutrients and to
remove carbon dioxide and other waste
products

3. Cardiovascular System-parts
• Also circulatory system
• Consists of: the heart, arteries, veins,
capillaries

4. Heart
• Four chamber muscular organ
• Comparable to the size of a closed fist
• Located in the mediastinum
– Behind sternum
– Between 2nd - 6th ribs
– Between T5-T8
• Apex – base of heart
– Located at the 5th
– intercostal space

5. Heart

6. External Heart Anatomy

7. Coverings of the Heart
• Pericardium – loose fitting sac
surrounding the heart
– Fibrous pericardium – tough, loose-fitting,
inelastic
– Serous pericardium
• Parietal layer: lines the inside of the fibrous
pericardium
• Visceral layer: adheres to outside of the heart
– Pericardial space: between parietal and
visceral layer
• Filled with 10-15mL of pericardial fluid
• Decreases friction

8. Walls of the Heart
• Epicardium – outer layer
– Epicardium = serous pericardium
• Myocardium – thick, contractile layer composed
of cardiac muscle cells
– Intercalated disks contain many gap junctions
– Allow cardiac muscle cells to function as a single unit
 syncytium
• Endocaridium – interior of cardiac wall
– Endothelial tissue
– Covers projections of myocardial tissue called
trabeculae

9. Walls of the Heart

10. Chambers of the Heart
• Atria – two superior chambers
– “Receiving chambers”
– Blood from veins enters atria
• Ventricles – two inferior
chambers
– “pumping chambers”
– Thick muscular walls to
– increase force of pumping
action
• Left > right
– Separated by interventricul
– ar septum

12. Valves of the Heart
• Permit blood flow in one direction during
circulation
• Atrioventricular valves (AV valves)
– Also cuspid valves
– Between atria and ventricles
• Semilunar (SL valves)
– Between R ventricle and pulmonary arteries
and L ventricle and aorta

14. Atrioventricular Valves
• Tricuspid valve
– Btwn R atrium and ventricle
– 3 flaps of endocardium
– Connected to ventricular papillary muscle
via chordae tendinae
• Bicuspid valve
– Btwn L atrium and ventricle
– Also called mitral valve
– Two flaps of endocardium

15. Semilunar Valves
• Pulmonary semilunar valve
– Btwn R ventricle and pulmonary trunk
• Aorta semilunar valve
– Btwn L ventricle and aorta

16. Operation of Heart Valves

17. The Heart:
Associated Great Vessels
• Aorta - leaves left ventricle
• Pulmonary arteries - leave right ventricle
• Vena cava - enters right atrium
• Pulmonary veins (four) - enter left atrium

18. Coronary Circulation
• Blood in the heart chambers does not
nourish the myocardium
• The heart has its own nourishing
circulatory system
– Coronary arteries
– Cardiac veins
– Blood empties into the right atrium via the
coronary sinus

19. Blood Supply to the Heart
• Right and left coronary arteries
– First branches off aorta
– Right coronary artery  right marginal
artery & posterior interventricular artery
– Left coronary artery  circumflex artery
& anterior interventricular artery
– Most of the blood goes to the L ventricle
– In 50% of the population, the R coronary
artery is dominant

20. Anterior view
Posterior view

22. Blood Supply to the Heart
• Anastomosis: Connections between blood
vessels that allow for collateral circulation
• Few exist between large branches of coronary
arteries
• In presence of an obstruction in a large
artery ischemia will result to a large area of
tissue
– Myocardial infarction (MI) (aka heart attack)
• Anastomoses do exists between smaller
branches of the R and L coronary arteries

23. Blood Supply to the Heart
• After traveling through the capillaries
of the heart, blood empties into the R
atrium via the coronary sinus

25. Conduction System of the Heart
• Four structures composed of modified
cardiac muscle
• Sinoatrial Node (SA Node)
– Pacemaker of the heart
– 100s of cells in the R atrium near the
opening of the superior vena cava
• Atrioventricular Node (AV Node)
– Small mass of cardiac muscle tissue
– Left lower border of R atrium

28. Conduction System of the Heart
• Atrioventricular Bundle
– Also Bundle of His
– Bundle of specialized cardiac muscle fibers
originating in the AV node
– Branches into R and L branches eventually
becoming Purkinje fibers
– Extend into the walls of the ventricles and
papillary muscles

29. Types of Blood Vessels
• Artery – carries oxygenated blood away
from the heart
– “distributors”
– Arteriole: small artery
– Precapillary sphincters: regulate the blood
flow into capillaries

30. Types of Blood Vessels
• Vein – carries unoxygenated blood
towards the heart
– Great ability to stretch (capacitance)
– Function as reservoirs: blood pools in the
valves then is pushed forward from the
pumping pressure
– Venules: small vein

31. Types of Blood Vessels

32. Types of Blood Vessels
• Capillaries – arterial system switches to
venous system
– “primary exchange vessels”
– Transport materials to and from the cells
– Speed of blood flow decreases to increase
contact time
– Microcirculation: blood flow between
arterioles, capillaries and venules

33. Types of Blood Vessels

34. Structure of Blood Vessels
• Tunica adventitia - outermost layer
– Fibrous connective tissue
– Holds vessels open; prevents tearing of
vessels walls during body movements
– Larger in veins than arteries
• Tunica media – middle layer
– Smooth muscle and elastic CT
– Helps vessels constrict and dilate
– Larger in arteries

35. Structure of Blood Vessels
• Tunica intima – innermost layer
– Composed of endothelium
– Semilunar valves present in veins
– One cell thick in capillaries

36. Circulatory Routes
• Systemic Circulation – blood flow from
the L ventricle to the body & back to
the R atrium
• Pulmonary Circulation – blood flow from
the R ventricle to the lungs and back to
the L atrium

40. Circulatory Routes

41. Aorta

42. Systemic Arteries
• Arch of aorta
• Subclavian (L and R)
• Brachiocephalic
• common carotid (L
and R)
• Axillary (L and R)
• Brachial (L and R)
• Radial
• Ulnar
• Abdominal aorta
• Common iliac
• External iliac
• Femoral
• Popliteal
• Posterior tibial
• Anterior tibial
• Dorsal pedis

44. The Vascular System

45. Systemic Veins
• Superior vena cava
• Inferior vena cava
• External jugular
• Internal jugular
• Brachiocephalic (L
and R)
• Subclavian (L and R)
• Cephalic
• axillary
• Basilic
• Median basilic
• Median cubital
• Common iliac
• External iliac
• Femoral
• Popliteal
• Great saphenous
• Small saphenous

47. Fetal Circulation
• Two umbilical arteries carry blood to the
placenta
• The placenta allows for exchange of oxygen
and nutrients from the mother. Maternal and
fetal blood do NOT mix.
• Umbilical vein returns oxygenated blood and
enters fetus via the umbilicus
• Foramen ovale – hole btwn the R and L atria
– Allows for blood to bypass the R ventricle and
pulmonary circulation

48. Fetal Circulation
• Ductus arteriosus – small vessel
connecting the pulmonary artery and
the aorta
– Allows for another bypass route from the
lungs
**Most of fetal blood is a mixture of
oxygenated and deoxygenated blood**

49. Fetal Circulation

50. Changes After Birth
• Umbilical vein become round ligament
• Umbilical arteries become umbilical
ligaments
• Foramen ovale closes after first few
breaths
– Full closure may take up to 9 months
• Ductus arteriosus contracts as soon as
respirations begin
– Become fibrous cord

51. Changes After Birth

52. Developmental Aspects of the
Cardiovascular System
• A simple “tube heart” develops in the
embryo and pumps by the fourth week
• The heart becomes a four-chambered
organ by the end of seven weeks
• Few structural changes occur after the
seventh week