Pathophysiology Flashcards
What makes up the first lesion possible in the artery before an atheromatous plaque?
Masses of lipid-laden macrophages
What do early plaques show in the intima?
Smooth yellow patches
What makes up the developed plaques?
Central lipid core with a fibrous tissue cap
What gives the structural strength of the atheromatous plaque?
The collagens in the tissue cap
What is the most important risk factor for atheromatous plaques?
Hypercholesterolaemia
What are the signs on clinical examination of major hyperlipidaemia?
Corneal arcus
Xanthelasma
When the atheromatous plaque ruptures what does it usually lead to?
Thrombosis
What are the main preventative measures for atheroma?
Smoking cessation
BP control
Weight loss
Exercise
What 3 things make up Virchow’s triad?
Changes in blood vessel wall
Changes in blood constituents
Changes in pattern of blood flow
Give an example of a change in blood vessel wall
Endothelial injury
What are the main risk factors for thrombosis?
Hypertension High cholesterol diet Smoking Age Gender Obesity
What is the definition of hypoxia?
Inadequate oxygen supply to meet needs of the tissue/organ
What is the definition of ischaemia?
Inadequate blood supply to tissue/organ
What is the definition of infarction?
Obstruction of blood supply to organ or region of tissue causing local death of tissue
How can an atheroma lead to ischaemia?
An atheroma will reduce the coronary circulation and thus it will lead to ischaemia
What are the main consequences of ischaemia?
MI Cerebral infarction Abdominal aortic aneurysm Peripheral vascular disease Cardiac failure
What is a transmural infarction?
Ischaemic necrosis which affects the full thickness of the myocardium
What is a subendocardial infarction?
Ischaemic necrosis mostly limited to a zone of myocardium under endocardial living of the heart
When heart is unable to clear blood from the ventricles, what is the consequence on the cardiac output?
Cardiac output decreases
If the Renal glomerular filtration rate decreases, what happens to the volume of fluid in the body?
It increases
Which are the pressures under the heading “Starling’s forces”?
Hydrostatic Pressure
Oncotic pressure
Which type of pressure pushes into the vasculature?
Oncotic pressure
What can a disturbance in Starling’s forces lead to?
Oedema
What happens to the hydrostatic pressure to cause a lymphatic obstruction?
The hydrostatic pressure is upset in some way
Give 3 examples of congestion?
Deep Vein thrombosis
Hepatic cirrhosis
Congestive cardiac failure
