2. Coronary Heart Disease (CHD) Grade 8, Semester 1 Year 2011-2012

3. Blood Supply to the Heart Coronary arteries: blood vessels that supply blood and oxygen to the heart muscle. Coronary arteries branch from the main aorta

4. Blood Pressure Measuring blood pressure can reveal cardiovascular problems Typical blood pressure for a healthy young adult is about 120/70 mmHg (systolic/diastolic). Hypertension (above 140/90 mm Hg) can cause CHD. Artery Rubber cuff inflated with air Artery closed 120 Pressure in cuff above 120 Pressure in cuff below 120 Pressure in cuff below 70 Sounds audible in stethoscope Sounds stop Blood pressure reading: 120/70 70

5. What is CHD? Coronary heart disease (CHD) is a narrowing of the small blood vessels that supply blood and oxygen to the heart.

6. What can cause CHD? Coronary heart disease is usually caused by a condition called atherosclerosis. Occurs when fatty material and a substance called plaque build up on the walls of arteries causing them to get narrow. As the coronary arteries narrow, blood flow to the heart can slow down or stop. This can cause chest pain (angina), shortness of breath, heart attack, and other symptoms.

7. One type of cardiovascular disease, atherosclerosis ◦Is caused by the buildup of cholesterol within arteries Figure 42.18a, b (a) Normal artery (b) Partly clogged artery 50 µm250 µm Smooth muscle Connective tissue Endothelium Plaque

8. Understanding CHD

9. Causes Bad genes (heredity) can increase your risk. You are more likely to develop the condition if someone in your family has had a history of heart disease Poor lifestyle: Smoking, lack of exercise, stress Diabetes High blood cholesterol

10. Hypertension, or high blood pressure ◦Promotes atherosclerosis and increases the risk of heart attack and stroke A heart attack ◦Is the death of cardiac muscle tissue resulting from blockage of one or more coronary arteries A stroke ◦Is the death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head

11. Symptoms Signs & Symptoms Chest Pain Shortness Of Breath Heart Attack None

12. Prevention Avoid or reduce stress. Don't smoke. Eat well-balanced meals that are low in fat and cholesterol and include several daily servings of fruits and vegetables. Get regular exercise. Keep your blood pressure below 130/80 mmHg if you have diabetes or chronic kidney disease, and below 140/90 otherwise Keep your cholesterol and blood sugar under control.

13. Treatment (Bypass surgery) Healthy blood vessel is removed from leg, arm or chest. Blood vessel is used to create new blood flow path in your heart. The “bypass graft” enables blood to reach your heart by flowing around the blocked portion of the diseased artery.