1. The Cardiovascular System
Chapter 15

2. Human Circulation Double loop circulation Pulmonary circuit
Systemic circuit

3. 15. 1 The Heart

4. Size and Location of the Human Heart
Bordered laterally by the lungs
Posteriorly by the vertebrae
Anteriorly by the sternum

5. Covering of the Heart Pericardium
Fibrous pericardium – surrounds a more delicate membrane
Visceral pericardium (epicardium)
Parietal pericardium – epicardium folds to line inside of fibrous pericardium
Between the parietal and visceral layers is pericardial cavity
Contains serous fluid
Reduces friction

6. Wall of the Heart
Epicardium
Myocardium
Endocardium

7. Epicardium Outermost layer of the heart
Corresponds with visceral pericardium
Contains
Capillaries and nerve fibers
Fat tissue along blood vessels

8. Myocardium Middle layer Cardiac muscle to pump blood
Muscle tissue is arranged in layers, separated by vascular connective tissue

9. Endocardium Innermost layer Epithelium, connective tissue
Blood vessels
Purkinje fibers
Specialized cardiac muscle fibers – propagate signal through heart
Lines all heart chambers, valves and lining extends into blood vessels

10. Heart Chambers and Valves
2 atria
2 ventricles

11. Atrium (Atria)
Upper chambers of the heart
Receive blood
Thin walled

12. Ventricles Lower chambers Very muscular
Right and Left Ventricles separated by the interventricular septum

13. Valves of the Heart Right Atrioventricular Valve (tricuspid)
Pulmonary Valve
Tricuspid valve
NO chordae tendineae or papillary muscles
Left Atrioventricular Valve (Mitral Valve)
Bicuspid valve
Aortic Valve

14. Heart Chambers and Valves
Right atrium
Receives blood from the superior vena cava, inferior vena cava
Coronary sinus – from myocardium

15. Valves Chordae tendineae – attach to tricuspid on ventricular side
Originate from papillary muscles
Prevent tricuspid valve from flipping into the atrium

16. Right Ventricle Thinner walls than the left ventricle
Pumps blood to the lungs
Exits heart and into the pulmonary trunk
Divides into left and right pulmonary arteries

17. Return to the heart…
From lungs, blood exits through pulmonary veins (4)
Two from right lung, two from left lung
Blood enters left atrium

18. Left Atrium
Blood passes from left atrium to left ventricle through the mitral valve

19. Left Ventricle and Aorta
Left ventricle contracts
Closing mitral valve
Sends blood to aorta through aortic valve

21. Blood Supply to the Heart
Coronary arteries – from aorta
Right and left
Cardiac veins – drain deoxygenated blood from heart
Join at the coronary sinus
Empties into right atrium

22. Label the Heart with Blood Flow

24. 15.3 Heart Actions

25. Heart Actions Systole Diastole Contraction
Depends on which part of the heart
Atrial systole
Ventricular systole
Diastole
Relaxation
Atrial diastole
Ventricular diastole

26. Cardiac Cycle
Cycle of contractions between the atria and ventricles

27. Heart Sounds Lubb Dubb Lubb – ventricular systole
AV valves are closing
Dubb – ventricular diastole
Pulmonary and aortic valves are closing

28. Heart Sounds Can tell you the condition of the heart valves
Murmur: some blood leaks back through the valve
Many murmurs are harmless
Some can be a sign of serious valve damage

29. Electrocardiogram

30. Electrocardiogram ECG (EKG)
Measures electrical changes within the myocardium during cardiac cycle

31. Steps of an ECG
P wave
QRS complex
Q wave
R wave
S wave
T wave

32. P Wave
Depolarization of atrial fibers

33. QRS Complex
Indicates depolarization of ventricular fibers prior to contraction

34. T Wave
Repolarization of ventricular fibers after contraction

35. ECG Uses Assess heart’s ability to conduct impulses
PQ interval: time to travel from SA node through AV node

36. SA Node Coordinates events of the cardiac cycle Sinoatrial node
Right atrium near opening to superior vena cava
Pacemaker: generates heart’s rhythmic contractions

37. AV Node Atrioventricular node
Coordinate contraction of ventricles together AND after the atria
Impulse travels to AV bundle (bundle of His) and move through ventricular myocardium
Through right and left bundle branches then to myocardium via Purkinje fibers
Allow ventricle to contract as one unit

38. Nodes of the Heart

39. Regulation of Cardiac Cycle
Vagus nerves: originate in the medulla oblongatta
Innervate and regulate heart

40. 15.4 Blood Vessels

41. Types of Blood Vessels
Arteries
Arterioles
Capillaries
Venules
Veins

42. Blood Vessel Tunics 3 layers (tunics) Tunica interna (innermost)
Epithelial cells
Tunica media (middle)
Smooth muscle
Tunica externa (outermost)
Tougher connective tissue, elastin, collagen

43. Arteries Muscular Very elastic Carry blood AWAY from the heart
Smaller arteries = arterioles

44. Veins
Little muscle
Large lumen (space for blood to pass through), less muscle
Brings blood to the heart
Contain valves
Flow through veins is assisted by skeletal muscle
Small veins = venules

45. Arteries vs. Veins

46. Capillaries Smallest blood vessel
Extension of innermost layer of arteries/veins – tunica interna
Single layer of epithelial cells
Allow for easy exchange of materials from blood to tissues

47. 15.7 Arterial System

48. Leaving the heart…

49. Leaving the heart… Aorta
Largest artery (diameter) in body
Three major arteries come from the aortic arch
Brachiocephalic artery
Left common carotid artery
Left subclavian artery

50. Brachiocephalic Artery
Supply blood to the upper limb, head
Divides to give rise to
Right common carotid artery
Right subclavian artery

51. Descending Aorta Extends from aortic arch down the body Thoracic aorta
Bronchial arteries
Esophageal arteries

52. More Descending Aorta Abdominal Aorta Celiac artery
Left gastric (upper digestive tract)
Splenic (spleen …duh…)
Hepatic (liver)
Phrenic artery (Diaphragm)
Superior mesenteric (Intestines (most))

53. Still the descending aorta…
And MORE from the Abdominal Aorta
Suprarenal (adrenal glands)
Renal (kidneys)
Gonadal (gonads …duh…)
Inferior Mesenteric (parts of the colon, rectum)
Lumbar (muscle of skin of posterior abdominal wall)
Medial Sacral (sacrum, coccyx)

54. Arteries of the Brain, Neck, Head
Vertebral
Through transverse processes of cervical vertebrae
Enter skull through foramen magnum
External carotid
Internal carotid

55. Arteries of the Shoulder and Upper Limb
From subclavian artery
Axillary artery (shoulder, upper chest)
Brachial artery (along the humerus)
Radial artery
Ulnar artery

56. Arteries of the Lower Limb
Abdominal aorta splits to form common iliac arteries
Internal iliac artery (pelvic region)
External iliac artery (main blood supply to lower limbs)
Inferior epigastric artery
Deep circumflex iliac artery

57. Arteries of the Lower Limb
External iliac artery becomes the femoral artery (deep femoral, superficial femoral)
Femoral artery becomes the popliteal artery as it passes over the patella
Divides
Anterior tibial artery
Posterior tibial artery

58. Venous System

59. How Veins Work Capillaries join to form venules
Venules join to form small veins
Small veins join to form large veins

60. Veins Veins typically are paired with an artery
Renal artery and the renal vein
Bring blood to the kidney from the heart, take blood from the kidney to the heart
BUT not always
Venous blood flow is assisted by skeletal muscle contraction

61. Veins Superior Vena Cava Inferior Vena Cava
Both lead to the right atrium from the body

62. Veins from the Brain, Head, Neck
External jugular vein
Internal jugular vein
Brachiocephalic vein
Right subclavian vein
Right axillary vein

63. Veins from the Upper Limb and Shoulder
Paired
Radial veins
Ulnar veins
Brachial veins

64. Veins from the Abdominal Viscera
Originate in the capillaries of the stomach, intestines, pancreas, spleen
Merge at the hepatic portal vein to the liver
Superior mesenteric vein (small intestine, portions of colon)
Inferior mesenteric vein (colon and rectum)
Gastric veins (stomach)
Splenic vein (spleen, pancreas)

65. Hepatic Portal System

66. What happens in the liver?
Regulation of glucose within the body
Phagocytosis of microorganisms
Breakdown of toxins
After the liver, blood enters the hepatic veins and the inferior vena cava

67. Veins from Lower Limb and Pelvis
Anterior tibial vein
Posterior tibial vein
Popliteal vein
Femoral vein
Great saphenous vein (largest vein in the body – extends from medial foot to the femoral vein)
External iliac vein

68. Cardiovascular Diseases and Abnormalities
Cardiac Arrest
Stroke
Aneurysm
Arteriosclerosis / Atherosclerosis
Murmur
Hypertension
Myocardial Infarction
What causes the disease/abnormality?
What are some possible effects of the disease/abnormality?
How is it diagnosed?
Possible treatments?

69. Cardiac Arrest
Cause: heart’s electrical system malfunctions, may be caused by abnormal or irregular heart rhythms
Effects: often results in death, brain death occurs within a few minutes if situation isn’t reversed, sudden cardiac arrest: death within 1 hr. of symptoms
Diagnosis: hard to detect because so sudden, but symptoms are- loss of consciousness, no breathing, no pulse, chest pain, weakness, pounding in chest, feeling faint
Treatments: CPR right away, defibulator

70. Stroke
Causes: Occurs when blood flow to the brain is interrupted or reduced
Arteries to brain become narrowed or blocked
Blood vessels in the brain leak
Effects:
Brain damage
Impairment – loss of normal function of part of the body (may be permanent)
Death
Diagnosis:
Blood tests
Physical examination
(CT) scan
MRI
Cerebral angiogram
Treatments:
Aspirin
Mechanical clot removal
Angioplasty and stents
Blood vessel repair
Stoke recovery and rehabilitation

71. Aneurysm
Part of the artery/cardiac chamber swells with blood forming a bubble
Most commonly found on the wall of the (left) aorta
Causes: atherosclerosis, smoking, hypertension, vaculities, cocaine usage, and/or genetic links
Effects: hemorrhage, other complications, or sudden death
Diagnosis: abdominal ultrasound, CT, MRI, regular screening
Treatment: wait and watch or surgery
All depends on the size of the aneurysm

72. Arteriosclerosis / Atherosclerosis
Arteriosclerosis- it is caused by the thickening and hardening of the arteries
Atherosclerosis- this is caused by the build up of fatty plaques in the arteries
Effects- blood flow will decrease and pressure will increase
Diagnosis- your doctor may find signs of narrowed, enlarged or hardened arteries during a physical exam.
A weak or absent pulse below the narrowed area of your artery
Decreased blood pressure in an affected limb
Whooshing sounds (bruits) over your arteries, heard using a stethoscope
Signs of pulsating bulge (aneurysm) in your abdomen or behind your knee
Evidence of poor wound healing in the area where your blood flow is restricted
Treatments- cholesterol medications, anti-platelet medication, beta blocker medications, calcium channel blockers, water pills, bypass surgery, thrombolytic therapy

73. Murmur Causes- Valve abnormalities:
Stenosis- narrowing of the heart valve.
Regurgitations- leaks blood backwards.
Sclerosis- mild narrowing.
Prolapse- Bowing of the heart valve.
Endocarditis- Infection of the heart.
Effects: Chest pain, shortness of breath, swelling of extremities.
Diagnosis: Patient history, physical examination.
Treatment: Monitored, antibiotics or surgery.
murmur

74. Hypertension High Blood Pressure (HBP)
Causes: Smoking, being overweight, lack of physical activity, too much salt in diet, high alcohol consumption, stress, old age, genetics, chronic kidney disease, adrenal and thyroid disorders.
Effects: nervousness, sweating, difficulty sleeping, facial flushing, blood spots in the eyes, dizziness, stroke, death
Diagnosis: blood pressure test (optimal blood pressure is less than 120/80 mmHG)
Treatments: lifestyle changes (diet, exercise, stop smoking, managing stress, limit alcohol consumption) and medication.

75. Myocardial Infarction
Heart Attack
Occurs when an artery leading to the heart is completely blocked off and the heart doesn’t get enough blood or oxygen, causing cells in that area to die( called an infarct)
Feeling of DOOM, squeezing pain, heaviness, tightness, pressure in center of chest, shortness of breath, death
ECG, blood tests, chest x-ray, stress test
Change lifestyle, medications, surgical treatments, nutrition and dietary supplements, diets for people with high blood pressure.