Coronary Heart Disease
Atheroma
-Fatty deposits (cholesterol & lipoproteins) that build up to form plaques within arterial walls. -Arterial diameter is reduced, so less blood flows to the tissues, meaning they receive less oxygen and glucose. Thrombosis -a blood clot/thrombus within a blood vessel, triggered by a bursting atheroma. -the thrombus can block vessels, depriving tissues of oxygen & glucose, so respiration stops (leading to cell death- infarction) Aneurysm -balloon like bulge in an artery due to weakened walls. -the bulge reduces blood flow to tissues, depriving them of oxygen & glucose. -the aneurysm may rupture, causing internal bleeding (haemorrhage) Myocardial Infarction -cardiac muscle cell death caused by obstruction in the blood supply (coronary arteries) -During an MI, cardiac muscle cells and deprived of oxygen and glucose, so respiration stops and the cells die. |
Risk Factors
Smoking
-carbon monoxide combines with haemoglobin instead of oxygen, so reduces the amount of oxygen that is delivered to the tissues.
-to catch up, the blood has to work harder, resulting in increased blood pressure, angina and a possible myocardinal infarction.
-nicotine causes an adrenaline release, increasing heart rate and blood pressure.
-nicotine makes the blood more sticky, making a thrombosis more likely.
-smoking decreases the amount of antioxidants, which protect cells from damage, causing an atheroma.
-Vitamin C contains antioxidants.
High Blood Pressure
-prolonged stress, certain diets, lack of excersize and obesity can increase your blood pressure.
-high blood pressure means the heart must work harder.
-aneurysms are more likely, and more likely to burst, causing a haemorrhage
-to resist pressure, arterial walls may harden, which reduces blood flow and therefore the amount of oxygen and glucose going to tissues.
-Salt raises blood pressure.
Blood Cholesterol
-HDLs are 'good'.
-HDLs take cholesterol from tissues to liver, where they are excreted.
-LDLs are 'bad'.
-LDLs take cholesterol from the liver to the tissues, where they are deposited in arteries and cause atheromas.
-LDLs are in saturated fats.
-carbon monoxide combines with haemoglobin instead of oxygen, so reduces the amount of oxygen that is delivered to the tissues.
-to catch up, the blood has to work harder, resulting in increased blood pressure, angina and a possible myocardinal infarction.
-nicotine causes an adrenaline release, increasing heart rate and blood pressure.
-nicotine makes the blood more sticky, making a thrombosis more likely.
-smoking decreases the amount of antioxidants, which protect cells from damage, causing an atheroma.
-Vitamin C contains antioxidants.
High Blood Pressure
-prolonged stress, certain diets, lack of excersize and obesity can increase your blood pressure.
-high blood pressure means the heart must work harder.
-aneurysms are more likely, and more likely to burst, causing a haemorrhage
-to resist pressure, arterial walls may harden, which reduces blood flow and therefore the amount of oxygen and glucose going to tissues.
-Salt raises blood pressure.
Blood Cholesterol
-HDLs are 'good'.
-HDLs take cholesterol from tissues to liver, where they are excreted.
-LDLs are 'bad'.
-LDLs take cholesterol from the liver to the tissues, where they are deposited in arteries and cause atheromas.
-LDLs are in saturated fats.
Questions
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