Cardiovascular Pathology Flashcards
What does the tunica intima consist of?
Single layer of endothelial cells
Basement membrane
Thin layer of ECM
How is vascular pathology different between blockage and rupture?
Blockage is preceded by narrowing
Rupture is preceded by weakening
What are the steps to vascular narrowing in response to vascular wall injury?
Endothelial activation
Smooth muscles develop and remodelling occurs
Intimal thickening occurs
What are the BP values and their associated danger zones?
Normal = <120 systolic + <80 diastolic
Elevated = 120 - 129 systolic + <80 diastolic
High BP (hypertension) stage 1 = 130 - 139 systolic OR 80 -89 diastolic
High BP stage 2 = 140 systolic or higher OR 90+ diastolic
Hypertensive crisis = >180 systolic and/or >120 diastolic
What is BP a function of?
CO x TPR
Why should BP be controlled?
Increased risk of atherosclerosis
Aortic dissection
Cardiac hypertrophy
Multi-infarct dementia
Heart failure
Renal failure
What causes hypertensive vascular disease?
Idiopathic or primary 90 - 95% of cases
Secondary 5 - 10%
Why must hypertension be treated?
If left untreated 50% of patients may die of ischaemic heart disease
Lowering diastolic BP by 5mmHg leads to 34% reduction in stroke risk and 21% reduction in risk of ischaemic heart disease
What is arteriolosclerosis?
Hardening of the arteries.
It is a generic term for arterial wall thickening and loss of elasticity
What are the patterns of arteriolosclerosis?
Arteriolosclerosis of small arteries and arterioles. May cause downstream ischaemic injury
Monckeberg medial sclerosis (calcification of the wall of arteries)
Atherosclerosis (the most important)
What determines the likelihood of atherosclerosis?
Acquired (Cholesterol, smoking, HTN)
Inherited (LDL, receptor gene mutations)
What happens in the early stages of atherosclerosis?
Atheroma forms or atheromatous/atherosclerotic plaque. Raised lesion, soft grumous core of lipid and fibrous cap.
What are the consequences of atherosclerosis?
Mechanical obstruction of blood flow
May rupture and lead to thrombosis
What determines the risk factors for atherosclerosis?
Age 40 - 60
Gender (Males and females post menopause)
Genetic (rarely mendelian and often polygenic)
Hyperlipidaemia (Hypercholesterolaemia)
Hypertension
Cigarette smoking
Diabetes mellitus
What is the myocardium composed of?
The left ventricle more organized spiral myocytes that contract with a coordinated wave of contraction. Right ventricle is less structured.
Atria are more haphazardly arranged and generate weaker contractile.
What causes acute haemodynamic stress?
Fluid overload
Abrupt valvular dysfunction
Myocardial infarction
Why does heart failure occur?
Failure of adaptive mechanisms to keep up with demands due to things like myocyte apoptosis
Intracellular cytoskeletal alterations
ECM deposition
What is the difference between systolic and diastoic dysfunction?
Systolic is progressive deterioration of myocardial contractile function. (ischamic injury, inadequate adaptation to pressure or
volume overload due to hypertension or valvular
disease, or ventricular dilation)
Diastolic is due to inability of heart chamber to expand and fill sufficiently during diastole (Left ventricular hypertrophy, myocardial fibrosis, constrictive pericarditis, or amyloid deposition)
How does right sided heart failure happen?
In patients with left sided heart failure
Isolated in patients with lung disorders hence the name cor pulmonale
What lung disorders can lead to right sided heart failure?
Primary parenchymal lung diseases and secondary conditions affecting pulmonary vasculature (primary pulmonary hypertension and recurrent pulmonary thromboembolism)
Pulmonary vasoconstriction (obstructive sleep apnea and altitude sickness)
What are the patterns of MI?
Transmural
Subendocardial
multifocal
How quick do the following return to normal after MI:
Troponin I
CK-MB
cTNT
Troponin I = 5 - 10 days hours
CK-MB = 48 - 72 hours
cTnT = 5 to 14 days
What are the types of angina pectoris?
Stable = relieved by rest
Prinzmetal variant = Anginal attacks unrelated to physical activity
Unstable = Caused by disruption of an atherosclerotic plaque with superimposed partial thrombosis and possibly embolization or vasospasm
What is the difference between valvular stenosis and insufficiency?
Stenosis = failure of valve to open completely
Insufficiency = failure of valve to close completely
What causes aortic stenosis?
Calcification and sclerosis anatomically normal or congenitally bicuspid aortic valves
What causes aortic insufficiency?
Dilation of ascending aorta, often secondary to hypertension and/or aging
What causes mitral stenosis?
Rheumatic heart disease
What causes mitral insufficiency?
Myxomatous degeneration
Which conditions need antibiotic prophylaxis following dental procedures?
History of infective endocarditis
Prosthetic cardiac valve or prosthetic material used for cardiac valve repair
Cardiac transplant that develops cardial valvulopathy
Unrepaired cyanotic congenital heart disease
Completely repaired congenital heart defect with prosthetic material or device
Any repaired congenital defect with residual defect at the site or adjacent to the site
Which dental procedures need antibiotic prophylaxis?
Manipulation of the periapical region of the teeth
Manipulation of gingival tissue
Perforation of the oral mucosa
Do not need prophylaxis:
Routine anesthetic injections through non-infected
tissue
• Taking dental radiographs
• Placement of removable prosthodontic appliances
• Placement of removable orthodontic appliances
• Adjustment of orthodontic appliances
• Placement of orthodontic brackets
• Shedding of deciduous teeth
• Bleeding from trauma to the lips or oral mucosa.
What should be provided to IE patients before their appointment?
Oral: Amoxicillin 2g for adults 50mg/kg for children
no oral: IM or IV 2g ampicillin or 1g cefazolin or ceftriaxone
