CP8-3 cardiovascular pathology 3 Flashcards
What is peripheral vascular disease?
Atherosclerosis of arteries supplying the legs (sometimes arms) leading to narrowing of the lumen and restriction of blood flow
What is the epidemiology of peripheral vascular disease?
Age >40
Obese people
Smokers
Men or post menopausal women (as oestrogen a protective factor)
People with family history
PMH of diabetes +/- hypercholestroaemia +/- hypertension
What is the aetiology of peripheral vascular disease?
Endothelial dysfunction due to oxidative stress —> fatty streak formation —> stable (fibrous) plaque forms —> plaque can become unstable —> narrows lumen —> reduces blood flow —> ischaemia —> tissue damage
What are the 6Ps of acute peripheral vascular disease symptoms?
Pale
Pulseless
Painful
Paralysed
Paraesthetic
Perishingly cold
… feet/limb
How does chronic peripheral vascular disease present?
With reduced pulse in ABI otherwise a symptom
With intermittent claudication with pain in limb upon exertion
With rest pain
With tissue loss
(Top to bottom, least to most severe)
What causes chronic peripheral vascular disease?
Gradual atherosclerosis
What causes acute peripheral vascular disease?
Plaque rupture or thrombus formation
What type of necrosis occurs in peripheral vascular disease?
Coagulative necrosis
What is giant cell arteritis aka temporal arteritis?
Type of vasculitis affecting the large arteries in the head.
Why is giant cell arteritis a medical emergency?
As it can lead to blindness
What is the aetiology of giant cell arteritis?
T cell mediated autoimmune damage of blood vessels via a type 4 hypersensitive reaction
What is the epidemiology of giant cell arteritis?
Older individuals (rarely found in patients under 50)
In US and Europe
Women > men
People with PMH of polymyalgia rheumatica
What is the pathogenesis of giant cell arteritis?
Cytokines releases in type 4 hypersensitivity reaction recruits macrophages and other inflammatory cells leading to chronic granulomatous inflammation. This thickens the arterial wall, narrowing the lumen, reducing blood flow and causing tissue damage due to ischemia
How do patients with giant cell arteritis preset?
Fatigue
Weight loss
Fever
Tender superficial temporal artery/ scalp
Jaw claudication when eating
Blurred vision
Blindness (can be permenant)
With a stroke
What is infective endocarditis?
Infection and inflammation of the endocardium mainly involving the valves
Who tends to get infective endocarditis?
People with…
…structurally abnormal valves e.g. due to congenital heart disease
…. Foreign material in heart e.g. prosthetic valves
…. Immunosuppression e.g. HIV
… bacteraemia due to IV drug use, long term IV catheter use, colorectal cancer and dental procedures
… normal healthy hearts but exposed to virulence organisms like s. Aureus
What bacteria can cause infective endoca?
Streptococcus e.g. viridans and bovis, and staphylococcus aureus or epidermis
Rarely fungi (usually in immunosuppressed) like candida and aspergillus
What is the pathogenesis of infective endocarditis?
Damage to endothelium up over valve causes fibrin deposition —> circulating bacteria colonise this fibrin —> vegetations form
What can infective endocarditis lead to and why?
Heart failure and murmurs due to vegetation damaging valves
AV block due to vegetations causing local abscesses
Jae way lesions, splinter haemorrhages, splenic infarct and kidney infarct due to emboli of vegetations
Fever and weight loss, and immune complex formation causing Roth spots, glomerulonephritis and oiler nodes due to san immune response to the infective endocarditis.
What is pericarditis?
Inflammation of the pericardial sac
What are the main classification of pericarditis?
Acute or chronic
What are the types of acute pericarditis?
Serofibrinous
Caseous
Haemorrhagic
Purulent
What is the main type of chronic pericarditis?
Constrictive
What is the aetiology of pericarditis?
Infections like Coxsackie B and TB
Autoimmune diseases like Dressler’s syndrome, SLE and rheumatic fever
Uraemia
Neoplasia
What is the pathogenesis of pericarditis?
There is acute inflammation in the pericardium leading to leaky vessels, accumulation of fluid in the pericardial sac. When becomes chronic, extracellular matrix and collagen deposits causes fibrosis and thickening of the pericardium. This reduces filling of the heart which can lead to heart failure
How does a patient with pericarditis present?
Central chest pain exacerbated lying down and laying flat
Pericardial friction rub heard on auscultation
Fever
Pericardial effusion which can lead to cardia tamponade
Heart failure
What is found in the pericardial sac alongside fluid in serofibrinous pericarditis?
Fibrin
What is found in the pericardial sac alongside fluid in purulent pericarditis?
Neutrophils
What is found in the pericardial sac alongside fluid in haemorrhagic pericarditis?
Red bloods cells
What is found in the pericardial sac alongside fluid in caseous pericarditis?
Caseous necrosis due to TB
What is myocarditis?
Inflammation of the myocardium (heart itself)
What is the epidemiology of myocarditis?
Anyone depending on cause
What is the aetiology of myocarditis?
Infection mainly viruses
Autoimmune conditions like SLE
Drugs
Sarcoidosis
What drugs can cause myocarditis?
Methylodopa
Sulphonamides
What is the pathogenesis of myocarditis?
Inflammation of myocardium leads to dysfunction including electrical dysfunction leading to arrhythmias +/- mechanical dysfunction like heart failure
How might patients present with myocarditis?
Asymptomatic
With chest pain
Heart failure
Arrhythmias
Sudden death
What is rheumatic fever?
A rare complication of a group A strep pharyngitis that affects other organs including the heart
What is the epidemiology of rheumatic fever?
Rare in UK now but still found in developing countries
In children
Often have history of sore throat
What is the aetiology of rheumatic fever?
Untreated group A strep infection e.g. strep pyogens with immune cross reactivity
What is the pathogenesis of rheumatic fever?
Group A strep causes a type 2 hypersensitivity reaction where antibodies are made against M protein on the surface of strep pyogenes bacteria. However these antivodies also recognise proteins on surface of cells in the heart, skin, joints and CNS
How do patients with rheumatic fever present?
With endocarditis (usually mitral stenosis), myocarditis or pericarditis
With subcutaneous nodules or erythema marginatum on the skin
Arthritis
Sydenham’s chorea
Fever
Malaise
What is cardiomyopathy?
Heart muscle disease separated into dilated, hypertrophic, restrictive and arrythmogenic
What is hypertrophic (obstructive) cardiomyopathy?
Cardiomyopathy where heart can’t fill or empty properly (left ventricle outflow obstruction) due to pump failure, relative ischaemia and electrical disruption
What is the aetiology of hypertrophic cardiomyopathy?
Genetics
Who gets hypertrophic cardiomyopathy?
Anyone can
How do patients with hypertrophic cardiomyopathy present?
Heart failure
Chest pain due to ischaemia
Arrhythmias and sudden death
Mural thrombus formation +/- embolisation
Why does hypertrophic cardiomyopathy contribute to intracardic thrombus formation?
As increased stasis of blood
What is dilated cardiomyopathy?
Dilated and thin walled ventricle chambers lead to impaired ventricular pumping (decreases LVEF) causing pump failure where heart can’t empty
What is the epidemiology of dilated cardiomyopathy?
Anyone but most common in males aged 20-50
What is the aetiology of dilated cardiomyopathy?
Often unknown
Can be autosomal dominant inherited gene mutation
Alcohol
Takotsubo
Infection like Coxsackie B
Pregnancy
Haemochromatosis
How do patients with dilated cardiomyopathy present?
Heart failure
Thrombus +/- emboli due to blood stasis
Arrhythmias and sudden death as electrical activity also affected
What is restrictive cardiomyopathy?
Impaired ventricular filling due to pump failure usually secondary to another disease
What is the aetiology of restrictive cardiomyopathy?
Idiopathic or secondary to amyloidosis, sarcoidosis, metastatic tumours or deposition of metabolites
What is the epidemiology of restrictive cardiomyopathy?
Dependent on cause but can affect anyone
How to patients with restrictive cardiomyopathy present?
Heart failure
Arrhythmias and sudden death
Mural thrombus formation +/- embolisation
What is arrythmogenic cardiomyopathy?
Impaired cell adhesion causing cells to detach and fibrofatty tissue to form to repair damage. This interferes with muscle contraction and electrical conduction leading to pump failure and arrhythmias
What is the epidemiology of arrythmogenic cardiomyopathy?
Most common in young males
What is the aetiology of arrythmogenic cardiomyopathy?
Genetics - autosomal dominantly
Mutation in desmosome proteins which are involved in myocyte adhesion
How to patients with arrhythmogenic cardiomyopathy present?
Palpitations
Syncope
Heart failure
Thrombus +/- emboli
Arrhythmias and sudden cardiac death which is often exercise induced.
