2. THE CIRCULATORY SYSTEM Health Science 1 Health Science 1

3. WHAT ARE THE FUNCTIONS OF THE CIRCULATORY SYSTEM ? Circulates blood through the body Transports water, oxygen and food to cells and removes wastes from the cells. Helps fight disease Helps maintain the correct body temperature

4. THE HEART The heart is a muscular pump. It is located in the center of chest slightly tilting to the left. It is divided into two halves by a central partition called the SEPTUM.

6. Each half is then, also divided by valves into an ATRIUM above (A for above) and a VENTRICLE below.

8. We, therefore have a right and left ATRIUM and a right and left VENTRICLE.

11. THE HEART AS A DOUBLE CIRCULATORY PUMP.

12. BLOOD VESSELS BLOOD VESSELS 1.Arteries 2.Veins 3.Capillaries There are 3 vessel types:-

13. ARTERIES The wall of the heart is supplied with blood from two small vessels called the coronary ARTERIES. These can be blocked by blood clots and when this happens blood supplied to part of the heart wall is cut off, resulting in sudden death. The structure of ARTERIES, VEINS and CAPILLARIES is different.

14. The ARTERIES have a relatively thick wall. Most ARTERIES and ARTERIOLES (very small arteries) carry oxygenated blood away from the heart. They are more elastic than VEINS and also have higher pressure. The PULMONARY ARTERIES are different, they carry de-oxygenated blood from the heart to the lungs. They pulsate as the heart beats.

15. Any vessel LEAVING the heart is called an ARTERY.

16. VEINS VEINS carry de-oxygenated blood to the heart. They have much thinner walls than arteries. They contain many VALVES which keep de- oxygenated blood flowing to the heart and avoid the possibility of blood flowing backwards. VEINS rarely pulsate.

17. They are less elastic than arteries. They carry blood at a lower pressure. The PULMONARY VEINS, which leave the lungs on the way to the heart, are different from other veins, they carry oxygenated blood. Any vessel ENTERING the heart is called a VEIN.

18. CAPILLARIES CAPILLARIES are vessels that link the ARTERIES with the VEINS. At one end they carry oxygenated blood which transfers supplies of oxygen and nutrients to the muscles. At the other end CAPILLARIES pick up waste and so carry de-oxygenated blood into the VEINS.

20. TO SUM UP THE DIFFERENCES BETWEEN CAPILLARIES, VEINS AND ARTERIES.

23. SMOKING The ARTERIES need to be clear and free from obstruction in order to carry blood and supplies to the working muscles. But these passageways can be blocked by lipids which can be caused by smoking. Nicotine, one of the main components of tobacco, affects the nervous system, which controls the HEART RATE.

25. HEART RATE increases which raises BLOOD PRESSURE. Other conditions associated with smoking include CHD and STROKES. It is said that risk of a heart attack is decreased after the smoker has stopped smoking for one year.

27. WHY DO WE NEED TO TAKE OUR BLOOD PRESSURE ? If you go to a doctor for a check up, you are very likely to have your blood pressure checked.

29. WHAT IS BLOOD PRESSURE ?

32. As you get older the blood vessel walls become less elastic and the small vessels do not expand to let through the blood pumped from the heart. This means that resistance to the flow of blood is increased and this means that blood pressure rises.

33. Blood pressure varies with: 1.AGE 2.GENDER 3.ALTITUDE 4.MUSCULAR DEVELOPMENT 5.STRESS 6.TIREDNESS

34. Guidelines The Seventh Report of the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC VII) uses the following guidelines to define HTN in adults: (Brashers, 2006, p.1) CategorySystolicDiastolic Normal<120and<80 Pre-hypertension120-139or85-89 Stage 1 hypertension 140-159or90-99 Stage 2 hypertension >160 or >100

35. Epidemiology I Epidemiology The most common primary diagnosis in the United States, 50 million American affected. The most common primary diagnosis in the United States, 50 million American affected. Only 70% are aware they have HTN Only 70% are aware they have HTN Of those aware of their HTN, only 50% are being treated. Of those aware of their HTN, only 50% are being treated. Only 25% of all hypertensive patients have their BP under control Only 25% of all hypertensive patients have their BP under control HTN is a risk factor for coronary artery disease (CAD), congestive heart failure (CHF), stroke, and renal failure HTN is a risk factor for coronary artery disease (CAD), congestive heart failure (CHF), stroke, and renal failure

36. What can I do to reduce the risk of high blood pressure ? 1.Check your weight 2.Limit your alcohol consumption 3.Avoid smoking 4.In some people too much salt may unbalance the body chemistry and affect blood pressure. 5.Avoid situations that cause stress, anxiety or worry.

37. Management of Hypertension Prevention Patient education Life-style modification Medication

38. 6. Exercise regularly- this will help to control stress, keep your blood pressure normal and your whole system in good shape.

39. REVISION

47. Walls of the heart are made up of three layers of tissue: Walls of the heart are made up of three layers of tissue: –Endocardium –Myocardium –Epicardium Atria and ventricles Atria and ventricles Heart valves Heart valves Conduction system Conduction system Coronary circulation Coronary circulation Heart

48. The Effects of Aging on the Cardiovascular System

49. Less efficient contraction Less efficient contraction Decreased elasticity of the arteries and veins Decreased elasticity of the arteries and veins Proper diet and regular exercise can help to keep the cardiovascular system healthy Proper diet and regular exercise can help to keep the cardiovascular system healthy Age-Related Changes

50. Disorders of the Cardiovascular System

51. Disorders of the blood Disorders of the blood –Anemia –Leukemia –Bleeding disorders Disorders of the blood vessels Disorders of the blood vessels –Atherosclerosis –Venous disorders Disorders of the heart Disorders of the heart –Coronary artery disease –Heart failure –Conduction disorders Types of Disorders

52. Atherosclerosis Atherosclerosis –Blocking of the arteries –Plaques build up on the inside of the arteries, restricting blood flow –Can lead to myocardial infarction (heart attack), stroke –Risk factors: high blood cholesterol, lack of exercise, smoking Disorders of the Blood Vessels

53. Venous disorders Venous disorders –Venous thrombosis: blood clots form in the veins; danger of embolism –Venous (stasis) ulcers: skin breakdown as a result of poor circulation Disorders of the Blood Vessels

54. Nonmodifiable cardiac risk factors Nonmodifiable cardiac risk factors –Age –Gender –Heredity –Body build Modifiable cardiac risk factors Modifiable cardiac risk factors –Smoking –Inactivity –Obesity –High-cholesterol diet Risk Factors for Cardiovascular Disease

55. Coronary artery disease Coronary artery disease –Disease of the arteries that supply the heart with oxygen and nutrients –Two closely related conditions: Angina pectoris: pain that occurs when heart muscle is deprived of oxygen Angina pectoris: pain that occurs when heart muscle is deprived of oxygen Myocardial infarction: heart attack; part of the heart muscle dies Myocardial infarction: heart attack; part of the heart muscle dies Heart failure Heart failure –Heart is unable to pump enough blood to meet the body’s needs –Types Cor pulmonale (right-sided heart failure) Cor pulmonale (right-sided heart failure) Congestive heart failure (left-sided heart failure) Congestive heart failure (left-sided heart failure) –Treated with medication; fluid intake may be restricted Conduction disorders Conduction disorders –Electrical impulses that cause the heart to contract cannot get through Heart Disease

56. In this test, sensors are attached to the person’s chest In this test, sensors are attached to the person’s chest Tracing of electrical activity of the heart on paper is called an electrocardiogram (EKG, ECG) Tracing of electrical activity of the heart on paper is called an electrocardiogram (EKG, ECG) Stress test: EKG obtained while a person exercises Stress test: EKG obtained while a person exercises Electrocardiography

57. In this test, sound waves are bounced against the body to produce an image In this test, sound waves are bounced against the body to produce an image Provides information like: Provides information like: –Size and shape of the heart –Its pumping strength –The location and extent of any damage to its tissues Echocardiography

58. Doppler ultrasound: sound waves are used to check the blood flow in the large arteries and veins of the arms and legs Doppler ultrasound: sound waves are used to check the blood flow in the large arteries and veins of the arms and legs Radiography: Allows the doctor to see the heart and vessels without actually entering the body Radiography: Allows the doctor to see the heart and vessels without actually entering the body Doppler Ultrasound and Radiography

59. Cardiac Rehabilitation

60. Help the person to regain strength and adopt heart-healthy habits Help the person to regain strength and adopt heart-healthy habits Help the person to begin an exercise program designed to strengthen the heart muscle and make it a more effective pump Help the person to begin an exercise program designed to strengthen the heart muscle and make it a more effective pump Help the person to learn healthy dietary changes Help the person to learn healthy dietary changes Provide supportive emotional therapy Provide supportive emotional therapy Focus of Cardiac Rehabilitation