Clinical Aspects of Cardiovascular Risk Flashcards
Most common cause of premature death?
Coronary Heart Disease - particularly in men
How does deprivation affect CVD risk?
Increased deprivation causes increased CVD risk
Reasons why CHD is the leading cause of death in the world?
Increased in no. of older people
Changes in underlying health habits, such as: Increase in smoking Dietary changes - increased cholesterol Sedentary lifestyle Rises in BP
Medical care focus on treatment rather than prevention
What is atherosclerosis?
Progressive disease characterised by plaque build-up within the arteries, which can partially/totally block the blood flow through as artery
Constituents of atherosclerotic plaque?
Formed from fatty substances, like cholesterol, cellular waste, calcium and fibrin. There is also inflammatory cell build-up
Complications of atherosclerotic plaque?
Bleeding into the plaque
Formation of a clot on the surface of the clot
If either happens and blocks the artery, an MI or stroke may result
Steps in atherosclerotic pathway?
Endothelial damage
Protective response - results in production of cellular adhesion molecules, such as cytokines, chemokines and growth factors
Monocytes and T lymphocytes attach to “sticky” surface of endothelial cells
Migrate through arterial wall to sub-endothelial space
Monocytes differentiate into macrophages take up oxidised LDL-C
Lipid-rich foam cells form the fatty streak and plaque
Causes of endothelial damage?
Haemodynamic forces (shear stress caused by e.g: hypertension)
Vasoactive substances
Mediators (cytokines) from blood cells
Cigarette smoke
Atherogenic diet
Elevated glucose levels
Oxidised LDL-C
What is atherothrombosis?
Formation of an acute thrombus in a vessel affected by atherosclerosis
Progression of atherothrombosis?
Initiated by changes in the vessel wall resulting from plaque disruption
Atherosclerotic plaque can become unstable and rupture, exposing components such as collagen to allow platelets to adhere to the damaged area and initiate thrombus formation
Thrombus can extend and occlude the vessel, leading to ischaemia and tissue injury
Risk factors for CVD?
Age Family history and ethnicity Hypertension Heart disease Diabetes Smoking Obesity Unhealthy diet (atherogenic) Oral contraception Previous strokes/TIA Binge drinking and substance abuse Inactivity
Modifiable risk factors for CVD?
Smoking Dyslipidaemia: raised LDL, low HDL or raised triglycerides Raised BP Diabetes mellitus Obesity Dietary factors Thrombogenic factors Lack of exercise Excess alcohol consumption
?Deprivation
Non-modifiable risk factors for CVD?
Personal history of CHD
Family history of CHD
Age
Gender
5 major classes of lipoproteins and functions?
Chylomicrons (largest) - synthesised in the gut after a fatty meal; transport dietary triglycerides from the gut to the sites of use and storage and are cleared rapidly from the bloodstream
VLDL (smaller than chylomicrons) - produced in the liver and are main carriers of endogenous (synthesised in the liver) triglycerides and cholesterol to sites of use/storage
IDL - formed during VLDL and chylomicron breakdown; involved in recycling of cholesterol by the liver, as well as formation of LDL in the blood. Also, implicated in atherogenesis
LDL - principal lipoproteins involved in atherosclerosis; OXIDISED LDL is the MOST ATHEROGENIC FORM as they are the main carriers of cholesterol
HDL (smallest) - return cholesterol from peripheral tissue to the liver, for excretion; protective against atherosclerosis
General rule for function of lipoproteins related to their size?
Smaller VLDL, IDL and LDL are all atherogenic
Large VLDL and chylomicrons are not
HDL carries cholesterol away from the arterial wall and is protective
LDL is more strongly associated with CHD events in which gender?
Males
