Cardiovascular Pathology 3 Flashcards
What is peripheral vascular disease?
Atherosclerosis of arteries supplying legs (or arms) leading to narrowing of the vessel lumen and restriction of blood flow
Who is peripheral vascular disease typically seen in?
- Age >40
- Obese people
- Smokers
- Family history
- Men (or post-menopausal women)
- Those with a PMH including:
- Diabetes
- Hypercholesterolaemia
- Hypertension
Peripheral vascular disease can either be chronic or acute. What is the aetiology of both?
- Chronic: gradual atherosclerosis –> narrows lumen –> reduced blood flow –> ischaemia –> tissue damage/death
- Acute: plaque rupture or thrombus formation –> narrows lumen –> reduced blood flow –> ischaemia –> tissue damage/death
What are the clinical features of acute peripheral vascular disease? (6 P’s!)
- Pale
- Pulseless
- Painful
- Paralysed
- Paraesthetic
- Perishingly Cold
Why are the clinical features of chronic PVD different? (Why do you not get the 6 Ps)?
Do NOT get 6 Ps as collateral vessels form but instead symptoms according to increasing severity
Clinical features of chronic PVD?
- Asymptomatic; found during a physical exam (ABI) i.e. reduced pulses
- Intermittent claudication; complaint of pain upon exertion (in leg)
- Critical limb ischaemia; rest pain and tissue loss
What is an ABI?
The ankle-brachial pressure index (ABPI) or ankle-brachial index (ABI) is the ratio of the blood pressure at the ankle to the blood pressure in the upper arm. Compared to the arm, lower blood pressure in the leg suggests blocked arteries due to peripheral artery disease.
What is giant cell arteritis (temporal arteritis)?
A type of vasculitis typically affecting the large arteries in the head. Considered a medical emergency as it can lead to blindness.
Aetiology of giant cell arteritis? What type of hypersensitivity is it?
Autoimmune blood vessel damage; this is type IV hypersensitivity as it is T cell-mediated
What PMH is typically linked to giant cell arteritis?
polymyalgia rheumatica
Pathogenesis of giant cell arteritis?
- 1) Chronic granulomatous inflammation
- 2) Thickens wall of artery
- 3) Narrows lumen
- 4) Reduced blood flow
- 5) Ischaemia
- 6) Tissue damage/death
Clinical features of giant cell arteritis?
- Flu-like symptoms;
- Fatigue
- weight loss
- Fever
- Pain;
- Tender superficial temporal artery/ scalp
- Jaw claudication (when eating)
- Vision problems;
- Blurred vision
- Blindness (can be permanent)
- Stroke
What is infective endocarditis?
Infection and inflammation of the endocardium (lining of the heart), mainly involving the valves (when a valve is affected by endocarditis, it tends to be become regurgitative instead of stenotic)
Infective endocarditis typically occurs in patients with structurally abnormal valves. What can cause structurally abnormal valves?
Rheumatic heart disease, congenital heart disease, age-related valve calcification
Who is infective endocarditis typically seen in?
- Structurally abnormal valves (rheumatic heart disease, congenital heart disease, age-related valve calcification)
- Foreign material in the heart (ICD, prosthetic valves)
- Immunosuppression (HIV)
-
Bacteraemia
- IVDU
- Long term IV catheter (dialysis pts)
- Colorectal cancer
- Dental procedures (“Prophylaxis not recommended routinely”)
Infective endocarditis can also occur in healthy patients with normal hearts after infection with what?
Virulent organisms (e.g. S. aureus)
What group of organisms is infective endocarditis typically caused by?
Bacteria
What 2 major groups of bacteria typically cause infective endocarditis? Which specific organisms?
- Streptococcus
- viridans
- bovis
- Staphylococcus
- aureus
- epidermis
What are these organisms causing infective endocarditis associated with?
a) S. viridans
b) S. bovis
c) S. aureus
d) S. epidermis
a) dental procedures
b) colorectal cancer
c) normal hearts of healthy patients
d) prosthetic valves
Which organisms causing infective endocarditis is associated with dental procedures?
Streptococcus viridans
Which organisms causing infective endocarditis is associated with colorectal cancer?
Streptococcus bovis
Which organisms causing infective endocarditis is associated with prosthetic valves?
Staphyococcus epidermis
2 types of fungi can also cause infective endocarditis (although rarely). What are these?
- Candida
- Aspergillus
Pathogenesis of infective endocarditis:
After valvular vegetations form in infective endocarditis, what 4 things can then happen?
- Vegetations damage valves
- Bacteria in vegetations form local abscess
- Bits of vegetations break off (emboli)
- Immune response to infection
What is the danger of bacteria in valvular vegetations forming local abscesses?
Can lead to AV block
What are Roth spots?
A haemorrhage in the retina
What are Osler nodes?
Osler’s nodes are painful, red, raised lesions found on the hands and feet; associated with infective endocarditis
What are Janeway lesions?
Janeway lesions are rare, non-tender, small erythematous or haemorrhagic macular, papular or nodular lesions on the palms or soles only a few millimeters in diameter that are associated with infective endocarditis and often indistinguishable from Osler’s nodes.
Janeway –> palms, non-tender
Osler’s –> tips, tender
What are splinter haemorrhages?
Splinter hemorrhages are tiny blood spots that appear underneath the nail.
What is pericarditis?
Inflammation of the pericardial sac
Pericarditis can be acute or chronic. How can these be defined?
Acute; <6 months
Chronic; >6 months
What are the 3 main groups of causes of pericarditis?
- Infections
- Autoimmune
- Miscellaneous
What infections can cause pericarditis?
- Viruses (Coxsackie B)
- Bacteria
- TB
- Fungi
- Parasites
Which virus is typically responsible for pericarditis?
Coxsackie B
What are the autoimmne causes of pericarditis?
- Rheumatic fever
- SLE
- scleroderma
- drug hypersensitivity
- post-MI (Dressler’s syndrome)
What is dressler’s syndrome?
a secondary form of pericarditis that occurs in the setting of injury to the heart or the pericardium e.g. post MI
What are the miscellaneous causes of pericarditis?
Uraemia, radiation, neoplasia, trauma (inc surgery)
Pathogenesis of pericarditis?
Acute pericarditis; what should you suspect if;
a) + caseous necrosis
b) + RBCs
c) + fibrin
d) + neutrophils
a) caseous pericarditis –> think TB
b) haemorrhagic –> think malignancy
c) serofibrinous
d) purulent –> think bacterial infections
What is involved in chronic pericarditis?
Fibrosis –> reduces filling of heart –> heart failure
Clinical features of pericarditis?
- Central chest pain (Exacerbated by breathing in, laying flat)
- Pericardial friction rub
- Fever
- Pericardial effusion (may lead to cardiac tamponade)
- Heart failure (with constrictive pericarditis)
Which type of pericarditis is ‘constrictive’?
Chronic –> due to fibrosis
What is myocarditis?
Inflammation of the myocardium
What viruses can lead to myocarditis?
- Viruses (COVID-19, Adenovirus “common cold”, Coxsackie A&B, ECHO, influenza, HIV, CMV)
- Bacteria (C. diphtheriae, N. meningococcus, Borrelia)
- Fungi (Candia, histoplasma)
- Protozoa (Trypanosoma cruzi “Chagas disease”)
- Helminths (Trichonosis)
What are the immune mediated causes of myocarditis?
- Post Group A streptococcus
- SLE/ other autoimmune conditions
- Drugs (methyldopa, sulphonamides)
- Rejection of heart transplant
How can sarcoidosis lead to myocarditis?
Cardiac sarcoidosis (CS) and giant cell myocarditis (GCM) are underdiagnosed inflammatory myocardial diseases. Sarcoidosis is a systemic disease characterised by granuloma formation and subsequent tissue scarring in various organs, most commonly in the lungs.
Pathogenesis of myocarditis?
- Inflammation of myocardium
- Dysfunctional myocardium
- Electrical dysfunction = arrhythmias/sudden death
- OR mechanical dysfunction = heart failure
Clinical features of myocarditis?
- Broad spectrum of changes
- Asymptomatic
- Chest pain
- Heart failure
- Arrhythmias
- Sudden death
What is rheumatic fever? From which infection does it result from?
A rare complication of group A streptococcal pharyngitis (S. pyogenes) that affects the heart (and other parts of the body)
What is common is history of rheumatic fever patients?
Sore throat
Pathogenesis of rheumatic fever?
What type of hypersensitivity reaction is rheumatic fever?
Type II
Cardiovascular clinical features of rheumatic fever?
- Pancarditis;
- Endocarditis;
- Mitral valve stenosis “fish mouth” most common valve lesion
- Vegetations “verrucae”
- Myocarditis
- Pericarditis
- Endocarditis;
Skin clinical features of rheumatic fever?
- Subcutaneous nodules
- Erythema marginatum
How can rheumatic fever present regarding the joints?
Arthritis
How can rheumatic fever present regarding the CNS?
Sydenham’s chorea; a neurological disorder of childhood resulting from infection via Group A beta-hemolytic streptococcus (GABHS), the bacterium that causes rheumatic fever. SC is characterized by rapid, irregular, and aimless involuntary movements of the arms and legs, trunk, and facial muscles.
General symptoms of rheumatic fever?
- Fever
- Malaise
What are cardiomyopathies? What are the 4 main types?
- WHAT: Literally means “heart muscle disease”
- 4 main types:
- Dilated
- Hypertrophic
- Restrictive
- Arrythmogenic right ventricular cardiomyopathy
What does the term ‘cardiomyopathy’ NOT include?
Term does NOT include heart disease from ischaemia, valve disease, CCF
What is hypertrophic cardiomyopathy?
Hypertrophic cardiomyopathy (HCM) is a disease in which the heart muscle becomes abnormally thick (hypertrophied). The thickened heart muscle can make it harder for the heart to pump blood
Pathogenesis of hypertrophic cardiomyopathy?
- Hypertrophy of LV
- Impaired ventricular filling
- +/- left ventricular outflow obstruction (1/3 cases) (HOCM)
- Relative ischaemia
Why can hypertrophic cardiomyopathy lead to mural thrombus formation +/- embolisation?
Due to increased stasis in LV due to hypertrophy
Clinical features of hypertrophic cardiomyopathy?
- Heart failure
- Arrhythmias and sudden death (especially in young athletes)
- Mural thrombus formation +/- embolization
- Chest pain (ischaemia)
What is dilated cardiomyopathy?
Dilated cardiomyopathy is a condition in which the heart muscle becomes weakened and enlarged. As a result, the heart cannot pump enough blood to the rest of the body.
Who does dilated cardiomyopathy typically affect?
Any age but commonly males aged 20 – 50
Aetiology of dilated cardiomyopathy?
- Often unknown
- AD genetic (up to 50% cases)
- Alcohol
- Catecholamines (Takotsubo)
- Pregnancy
- Haemochromatosis
- Infection (inc Coxsackie B)
- Plus lots of others
Pathogenesis of dilated cardiomyopathy?
Dilated and thin walled ventricular chambers –> Impaired ventricular pumping (i.e. decreased LVEF)
Clinical features of dilated cardiomyopathy?
- Heart Failure
- Thrombus +/- emboli
- Arrhythmias and sudden death
What is restrictive cardiomyopathy?
Restrictive cardiomyopathy (RCM) is a condition where the chambers of the heart become stiff over time. Though the heart is able to squeeze well, it’s not able to relax between beats normally. This makes it harder for the heart to fill with blood. The blood backs up in the circulatory system.
Restrictive cardiomyopathy can be idiopathic or 2ary (infiltration). What can it be 2ary to?
- Amyloidosis
- Sarcoidosis
- Metastatic tumours
- Deposition of metabolites (inborn errors of metabolism)
Pathogenesis of restrictive cardiomyopathy?
Impaired ventricular filling
Clinical features of restrictive cardiomyopathy?
- Heart failure
- Arrhythmias and sudden death
- Mural thrombus formation +/- embolization
What is arrhythmogenic right ventricular cardiomyopathy (ARVC)?
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a disease of the heart muscle. In this disease, fatty fibrous tissue replaces normal heart muscle.
Pathogenesis of arrhythmogenic right ventricular cardiomyopathy (ARVC)?
RV myocyte adhesion impaired due to mutation in desmosome proteins –> cells detach –> fibrofatty tissue forms in attempt to repair damage –> interferes with muscle contraction and electrical conduction
Clinical features of arrhythmogenic right ventricular cardiomyopathy (ARVC)?
- Palpitations
- Syncope
- Heart failure
- Thrombus +/- emboli
- Arrhythmias and sudden cardiac death (often exercise induced)
Overall summary:
