1. Cardiovascular system
Heart
The size of persons fist
Less than 500gm in weight.
Apex at the level of 5th intercostals space
Base is where great vessels emerge, beneath 2nd rib
Receive 5% of cardiac output.

2. Pericardium Serous membrane, formed of two layers
Visceral layer: on external surface of the heart.
Parietal thick layer, protect heart, anchor it to surrounding structures like diaphragm, reinforced superficially by dense connective tissue
Lubricating serous fluid secreted by visceral layer is present pericardial membrane

4. Is formed by three layers
The wall of the heart
Is formed by three layers
Outer layer epicardium (visceral pericardium)
Middle layer myocardium which is thick bundle of cardiac muscle twisted into ring like arrangements
It is reinforced internally by dense fibrous connective tissue called skeleton of the heart
Deep layer endocardium thin glistening sheet of endothelium enclose the heart and continuous with great vessels in and out

5. Chambers of the heart Two atria, receiving chambers, thin wall.
Two ventricles are discharging chambers, thick wall
The left ventricle form the apex
The right ventricle form anterior surface.
Septum divides heart to RT, lt halves.
Interatrial, interventricular septum.

10. Heart is double pump
RT is the pulmonary circuit. It receives oxygen poor blood by superior and inferior vena cava, and pumps it through pulmonary trunk, which divides into RT, lt pulmonary arteries.
The four pulmonary veins return blood to the heart.

12. Aorta: pump blood through systemic circulation to the body.
Heart Body Heart
A left ventricle is thicker than right ventricles.
Atrioventricular valves
Tricuspid between RT atrium, and RT ventricle
Mitral between lt atrium and ventricle
They prevent back flow of blood to atria as they are one way valve,mitral valve have two cusps (bicuspid)
Chordae tendineae (heart strings) anchor the heart to wall of ventricles
Semilunar valves: guard the arteries which leave the heart

13. Pulmonary valve: guard pulmonary artery which leave RT ventricle
Aortic valve: guard the aortic artery which leave lt ventricle
Each valve has three cusps

14. Blood supply to the heart
The right and left coronary arteries
They arise from ascending aorta
The right coronary give posterior interventricular, and marginal
The left coronary give anterior interventricular and circumflex arteries
Angina pectoris
Myocardial infarction

15. Major arteries of systemic circulation
Aorta
Arise from the left ventricle.
It is the largest artery in the body.
Start as the ascending aorta, then continue as aortic arch, curve downward as descending aorta, ends in the diaphragmatic opening by becoming abdominal aorta.

17. Branches of the thoracic aorta
Branches of ascending aorta:
Rt and left coronary arteries
Branches from aortic arch
Brachicephalic, lt common carotid, lt subclavian arteries
Brachiocephalic artery divides in to RT common carotid, RT Subclavian arteries behind Rt sternoclavicular joint.

18. Common carotid artery divides into:
External, and internal carotid arteries at level of thyroid cartilage C4
External carotid artery is the artery to the neck, supply face tongue, thyroid.
Internal carotid artery supplies the brain.

19. Subclavian artery gives vertebral artery to the brain.
Continue as axillary artery in axilla, then brachial artery in the arm, divide into radial and ulnar arteries at elbow joint.

20. Abdominal aorta give
Celiac trunk to supply liver, spleen, stomach
Superior and inferior mesenteric arteries to large and small bowel
RT,and LT renal arteries to kidneys
Gonadal arteries to ovaries and testes

22. Abdominal aorta ends at level of L3-L4 by dividing into RT and lt common iliac arteries. Common iliac artery divides into external and internal iliac arteries. Internal iliac artery supply pelvic organs. External iliac artery continue as femoral artery in thigh, then popliteal artery in back of knee, then divide into anterior and posterior tibial arteries in the leg.

23. Major veins of systemic circulation
Superior vena cava for upper part of the body, head neck, and upper limb
Inferior vena cava for lower part of the body, abdomen pelvis and lower limb.

24. Veins of clinical importance
Cephalic, and basilic veins, at lateral and medial aspect of fore arm, median cubital vein at elbow region connect the two; deep to it is the brachial artery.
External and internal jugular veins from head and neck
Great saphenous vein begins at in front the medial malleolus, and end in femoral vein.
Hepatic portal vein drain the digestive system to liver

27. Circle of Willis Arterial blood supply to the brain
15% of cardiac output
The grey matter contain more capillaries than white matter
Formed by
Internal carotid artery
Vertebral artery

28. Internal carotid artery, of common carotid artery inter the skull through temporal bone (carotid canal)
ICA divides into
Anterior cerebral artery
Middle cerebral artery
Vertebral arteries, enter skull through foramen magnum

29. Right and left vertebral arteries, which are branches of subclavian arteries, join to form basilar artery, which divide into two posterior cerebral arteries
Basilar artery supply blood to cerebellum, and brain stem
The anterior and posterior blood supply are united by small communicating arteries

32. Circle of Willis

33. Posterior cerebral artery supply, center of vision, smell, thalamus, and mid brain
Anterior cerebral artery supply motor and sensory areas of lower limbs
Middle cerebral artery supply motor and sensory areas of rest of the body

34. Hepatic portal circulation
Portal vein
Is formed by union of
Superior mesenteric vein and Splenic vein behind neck of pancreas
Portal vein blood contain nutrients from digestion in the gut, and deliver them to liver, some of nutrients are stored or processed
Blood leave the liver through hepatic veins which drain into inferior vena cava.

36. Hepatic portal circulation

37. Superior mesenteric vein drain blood from small bowel Inferior mesenteric vein drain the colon in to Splenic vein.

38. STRUCTURE OF BLOOD VESSELS
Endothelium
Smooth muscle
Connective tissue
Collagen fibers
Elastic fibres
Tunica intima
Tunica media
Tunica adventitia

39. MUSCULAR ARTERY

40. ARTERIOLE

41. CAPILLARIES

42. STRUCTURE OF VEINS