Cardiovascular disease and pathology Flashcards
Why is cardiovascular disease important?
*7 million people in the UK living with cardiovascular disease
*Will be a regular feature when taken history in clinics.
*Relevant in dentistry
Statistics on hypertension.
Depending on criteria said to be present in 20-30% of the adult population
Persistently raised blood pressure > 140/90 mm Hg
90% No cause found = Primary / Essential hypertension
10% Cause found = Secondary hypertension
What are the causes of Primary (Essential) Hypertension?
Most common cause of preventable disease in developed world
Normally detected between 20-50 years of age
Has a Multifactorial Aetiology
There may be Genetic factors
There may be Environmental factors:
o Obesity (ensure correct cuff size)
o Alcohol
o Salt intake
o Stress
What causes secondary hypertension?
- Renal disease – E.g. diabetic nephropathy, chronic glomerulonephritis, adult polycystic disease
- Pregnancy
- Endocrine disease –E.g. Conn’s syndrome, adrenal hyperplasia, phaeochromocytoma, Cushing’s syndrome, acromegaly
- Drugs – E.g. Cortocosteroids, oral contraceptive pill
- Coarctation of the aorta – there is a narrowed area can lead to high blood pressure
How is hypertension diagnosed?
- Measurement of blood pressure on at least 3 occasions over 3 month period
- Patients often require a 24 hour monitor so continuous recordings can be analysed.
How is secondary hypertension treated?
Secondary hypertension – treat cause if possible
How is primary hypertension treated?
Primary / Essential hypertension you would give General advice (BHS):
* Weight loss
* Increase exercise
* Reduce alcohol
* Stop smoking
* Reduce salt intake
* Increase fruit and vegetable intake
How is primary hypertension medically treated?
Medical treatment:
* ACE Inhibitors (eg captopril)
* Angiotensin II receptor blockers (eg candesartan)
* B β-blockers (eg atenolol)
* Ca channel blockers (eg nifedipine)
* Diuretics (eg bendroflumethiazide)
Before giving medication must look into the cause of hypertension, age, co-morbidities of the patient.
What are the complications of hypertension?
- Heart failure
- Stroke – cerebrovascular accident (CVA)
- Coronary artery disease / Myocardial infarction (MI)
- Renal failure
- Peripheral vascular disease
What is the dental relevance of patients with hypertension?
- Minimise stress and pain to minimise further increase in BP which may precipitate cerebral vascular accident (CVA), MI
- No problem with adrenaline in LA (as long as intravascular injection avoided)
- Controlled hypertensive – treat as normotensive (treat as normal)
- Uncontrolled hypertensive (>140/90mmHg) – delay elective treatment. Refer to GP.
- Severe hypertension (>180/110mmHg) – Refer urgently to GP or hospital
- Post-operative bleeding more likely
- Patient likely to be taking aspirin
What are the oral manifestations of hypertension medication?
ACE inhibitors:
* Loss of taste
* Angioedema
* Lichenoid reactions
β-blockers: Lichenoid reactions
Ca channel blockers: Gingival overgrowth
Diuretics: Xerostomia
What does a normal artery look like?
normal intima:
* <0.1mm thickness
* Loose fibrous tissue
* Endothelial layer on top forms a barrier between blood and vessel wall/
What does an artery look like with Atherosclerosis?
Fatty streaks present in 45% of infants dying in the first year of like and these are seen as minimally elevated 1-2mm yellowish dots. It is reversible at this stage.
What is Atherosclerosis?
Widely prevalent disease affecting large elastic and muscular arteries.
Thickening of the intima: composed of lipid derived from plasma and deposits of extra connective tissue make calcify overtime.
What are the main sites of Atherosclerosis?
Main site of occurrence are:
* Aorta
* Carotid
* coronary arteries
* more peripheral leg of diabetics
How are atheromas formed?
- LDL into intima.
- Once entered the LDL is Oxidised, sends chemotactic messages to monocytes.
- Ingestion of LDL by monocytes / macrophages.
- Macrophages sends growth factor signals which leads to the stimulation of smooth muscle cell migration and connective tissue synthesis.
- Death of lipid containing macrophages, spillage of lipid and cholesterol
Increased entry of LDL is more likely when there is endothelial damage, this may be due to turbulent blood flow, hypertension and damage to endothelial cells due to toxins in cigarettes.
What causes Hyperlipidaemia and LDL:HDL imbalance?
Maybe due to diet but could also be due to:
* Familial hypercholesterolaemia
* Decrease receptors (cells which aid in elimination via liver) for LDL cholesterol
* Increased circulating levels of LDL
What is HDL?
Good type of cholesterol
Blocks several process involved in the formation of atheroma:
o Blocks oxidation of LDL
o Actively block attachment of monocytes inhibiting entry
o Blocks growth factors from LDL containing macrophages reducing smooth muscle and fibroblastic proliferation.
o Make platelets aggregation
How is hypertension linked with atheroma?
Degree of atherosclerosis has positive correlation with hypertension
Haemodynamic forces which exits in patient with hypertension causes damage to endothelial cell and facilitates passage of LDL intima.
what is advanced atherosclerosis?
Sex: primarily a disease of men until 7/8th decade more elderly women are affected as protective effect of female sex hormones are lost.
Cigarette smoking can lead endothelial damage allowing LDL to enter.
Diabetes increased incidence of hyperlipidaemia and microvascular damage.
Regression of plaque could be due to change of diet and positive life style changes.
If no lifestyle change this could lead to:
* Interference with blood flow to target organs (ischaemia/infarction)
* Thrombosis
* Embolisation
