Vascular diseases Flashcards
Atherosclerosis
An inflammatory disease of large and medium-sized systemic arteries characterised by the formation of lipid-rich plaques in the vessel wall.
Atherosclerosis Epidemiology and modifiable RF
Almost universally present to some degree in all individuals with ageing.
Non modifiable RF: age, males, Family Hx
Modifiable RF: Smoking, alcohol, poor diet/high cholesterol, obesity/low exercise, stress.
Comorbidities that increase the risk:
Diabetes mellitus, hypertension, Inflammatory conditions e.g. RA, and hyperlipidaemia.
Atherosclerosis Pathology
Endothelial injury leads to an inflammatory and activation of the immune system - fibroproliferative reaction in the artery, culminating in lipid plaques as a response to injury.
May form stable or unstable plaques.
These plaques cause:
1) Artery wall to stiffen leading to hypertension.
2) Stenosis causing reduced blood flow E.g. PVD
3) Plaque ruptures giving of thrombus that can travel down the blood vessel, blocking it and causing ischaemia - main cause of Heart attack
- Endothelium may be damaged by multiple factors: including smoking, hyperglycaemia, and oxidised LDL (Oxidized Low-Density Lipoprotein) - from bad cholesterol/fatty foods
- Oxidised LDL is particularly potent at driving atherosclerosis through its proinflammatory and procoagulant effects. More likely to cause a thrombosis
Stable plaques
Few inflammatory cells and a thick fibrous cap narrow the lumen of the artery, but are less likely to cause acute complications.
Cause symptoms of reversible ischaemia in the supplied organ, e.g. angina pectoris, chronic lower limb ischaemia.
Unstable plaques
More inflammatory cells have a thin fibrous cap more liable to complications like erosion, cracking, or rupture.
Cause acute ischaemic events, e.g. acute coronary syndromes, stroke, acute lower limb ischaemia.
Peripheral Vascular Disease (PVD)
A narrowing or blockage of the arteries that supply blood to the extremities. PVD most commonly affects the arteries in the lower limbs but can also occur in the arms or other peripheral arteries.
PVD Epidemiology
Increasing age, especially after 65 (or after 50 if you have risk factors for atherosclerosis).
Smoking, diabetes, high blood pressure, high cholesterol levels, obesity, and a sedentary lifestyle.
PVD Pathology
Often caused by atherosclerosis, a condition characterised by the buildup of plaque (cholesterol, fat, and other substances) on the inner walls of the arteries. This buildup leads to a reduction in blood flow, resulting in inadequate oxygen and nutrient supply to the affected areas.
PVD S&S
Claudication: This is the most common symptom of PVD. It refers to pain, cramping, or fatigue in the muscles of the legs, particularly during physical activity or walking. The pain typically subsides with rest.
5Ps:
Pain
Paresthesia
Pulselessness
Palar
Pertin cold - cold to touch
- Changes in skin colour, the affected area may appear pale, bluish, or discoloured.
- Slow-healing wounds or ulcers
- Slower growth of the toenails
- Sores on the toes, feet or legs that won’t heal - trash toes
Leriche syndrome
PVD in the aortic or illiac vessels
Thigh = buttocks claudication
Male impotence
Pulslessness femoral pulse
PVD Investigations
Compare blood pressure in the arms and legs, Doppler ultrasound
MRA
PVD management
In severe cases, PVD can result in critical limb ischemia, a condition characterized by severe pain at rest, non-healing ulcers, and the risk of tissue damage or limb loss.
Lifestyle modifications
Surgical interventions to remove blockages or bypass the narrowed arteries.
Hypertension (S)
High blood pressure, characterised by persistently elevated blood pressure in the arteries
Hypertension Epidemiology
The risk of high blood pressure increases with age. Until about age 64, high blood pressure is more common in men. Women are more likely to develop high blood pressure after age 65.
Black people
Family history
Hypertension Patho
Blood pressure is product of cardiac output (Heart rate
x Stroke volume) and total peripheral vascular resistance.
Phsyiological process of BP: in the liver it creates angiotensin, when the kidney senses a low amount of water going through it it release renin which stimulates angiotensin to go through the lungs and ACE and converts it to ACE 2 which stimulates the medullary cortex to produce aldosterone in the adrenal glands that are on the kidneys and effectively increases the blood pressure.
Blood leaves the left ventricle through the aorta and influences specialised cells in the aortic arch (also within the carotid artery)
Increases and decreases in pressure are registered and sent to the medulla oblongata (cardiovascular centre)
If pressure is high the medulla stimulates vasodilation and a decrease in cardiac output
If the pressure is low the medulla stimulates vasoconstriction: an increase in cardiac output
In response to low cardiac output
1) In response to low cardiac output the sympathetic nervous system will cause Alpha and Beta-adrenoreceptor changes which stimulate an increase in cardiac output
2) In response to poorly oxygenated blood the nephrons of the juxtaglomerular apparatus will cause renin to be released which reacts with angiotensin 1reacts with angiotensin 2 reacts with blood vessels vasoconstrictionraises total peripheral resistance
3) Angiotensin 2 also reacts with the adrenal cortices which release aldosterone acts on nephrons to retain sodium and waterraises BP and increases blood volume
3 Types of hypertension
Primary
Secondary
Malignant
Primary
For most adults, there’s no identifiable cause of high blood pressure. It tends to develop gradually over many years. Atherosclerosis, increases the risk of high blood pressure.
Secondary
Caused by an underlying condition. It tends to appear suddenly and cause higher blood pressure than does primary hypertension. Conditions and medicines that can lead to secondary hypertension include:
Renal disease (80%): mechanism is generally sodium and water retention.
Adrenal gland tumors
Blood vessel problems present at birth, also called congenital heart defects
Kidney disease
Thyroid problems
