Flashcards in Cardiovascular diseases 3 Deck (87):
What is endocarditis?
- Inflammation of the endocardium of the heart
- Prototypical lesion = “vegetation” on valves
What are the two main forms of endocarditis?
- Infective endocarditis
- Clinically important
- Non-infective endocarditis
- Nonbacterial thrombotic endocarditis (NBTE)
- Endocarditis of SLE (Libman-Sacks Disease)
What is infective endocarditis?
Colonization / invasion of heart valves or heart chamber endocardium by a microbe (bacteria and fungi)
What are the 'vegetations'?
- Mixture of thrombotic debris and organisms
- Destroy underlying cardiac tissues
- Aorta, aneurysmal sacs, blood vessels, prosthetic
valves can also be infected
What is acute infective endocarditis?
- Can occur with infection of a previously normal heart valve
- Caused by highly virulent organisms
- Necrotizing, ulcerative, destructive lesions
- Difficult to cure with antibiotics and usually require surgery
- Death frequent days to weeks despite treatment
What is subacute infective endocarditis?
- Organisms of lower virulence
- Insidious infections of deformed valves
- Less destructive
- Protracted “wax and wane” course of weeks to months
- Cured with antibiotics
What are the aetiologies of infective endocarditis?
- Cardiac/valvular abnormalities
- Rheumatic heart disease
- MV prolapse
- Valvular stenosis (calcification etc)
- Artificial (prosthetic) valves
- Unrepaired and repaired congenital defects
- Bicuspid AV
What sort of investigation should you perform if you discover Strep. bovis AND endocarditis in a patient?
Investigation for bowel cancer
How does an infection get to the heart?
- Any route of bacteria into the blood stream e.g.
- Dental abnormalities, IVDU, wounds, bowel cancer…..
What organisms are commonly associated with endocarditis?
Streptococcus viridans from the mouth
- Endocarditis in native but damaged / abnormal valves
- 50-60% cases
S. aureus from the skin
- 10% to 20% of cases overall esp. IVDU
Coagulase-negative staphylococci (e.g. S. epidermidis)
- Commonly infect prosthetic heart valves
What are the pertinent features of the vegetations of acute infective endocarditis?
- Friable, bulky, potentially destructive
- AV, MV, right heart (especially in IVDUs)
- Single, multiple and often more than one valve
- Can erode myocardium abscess (ring abscess).
- Emboli contain large numbers of virulent organisms
- Abscesses at the sites where emboli lodge
- Septic infarcts or mycotic aneurysms
Sub-acute IE – Less destruction
What are the clinical features of infective endocarditis?
- Most consistent sign
- Rapidly developing fever, chills, weakness
- Can be slight or absent, particularly in the elderly
- May be only presentation
- Loss of weight / flu-like syndrome.
- 90% of patients with left-sided IE
- New valvular defect or represent a pre-existing abnormality.
What are the complications of infective endocarditis?
- Immunologically mediated conditions e.g. glomerulonephritis
What are the pathological signs of infective endocarditis?
- Splinter / subungual hemorrhages
- Janeway lesions
- Erythematous or haemorrhagic non-tender lesions on the palms or soles
- Osler’s nodes
- Subcutaneous nodules in the pulp of the digits
- Roth spots
- Retinal haemorrhages in the eyes
What are Janeway lesions?
Janeway lesions are non-tender, small erythematous or haemorrhagic macular or nodular lesions on the palms or soles only a few millimeters in diameter that are indicative of infective endocarditis
What are Osler's nodes?
Painful, red, raised lesions found on the hands and feet
What are Roth spots?
Retinal hemorrhages with white or pale centers
What mnemonic is associated with infective endocarditis?
F – Fever
R – Roth spots
O – Osler’s nodes
M – Murmurs
J – Janeway Lesions
A – Anaemia
N – Nail (splinter) haemorrhage
E – Emboli (septic)
What is non-bacterial thrombotic endocarditis (NBTE)?
Occurs in debilitated patients (e.g. cancer or sepsis)
- AKA “marantic endocarditis”
Associated with a hypercoagulable state
- Hence DVT, PE and mucinous adenocarcinomas!
- Pro-coagulant effects of tumour-derived mucin or tissue factor
Part of trousseau syndrome of migratory thrombophlebitis
Endocardial trauma / indwelling catheter (e.g. central line)
What are the features of vegetations in NBTE?
- Small (1 to 5mm) sterile thrombi on valve leaflets
- Singly or multiple on line of closure of leaflets or cusps
- Not invasive / no inflammatory reaction minimal local effect
- Systemic emboli
- Infarcts in the brain, heart etc.
What is rheumatic fever?
Acute, immunologically mediated, multi-system inflammatory disease following group A streptococcal pharyngitis
What are Aschoff bodies?
- Distinctive cardiac lesions
- Foci of T-cells, plasma cells and macrophages
- Can be found in all three cardiac layers (pancarditis)
What are the vegetations called in rheumatic fever?
What mitral valve changes are seen in rheumatic fever?
- Virtually ONLY cause of mitral stenosis
- Leaflet thickening
- Virtually always involved in chronic disease
- MV only in most cases cases
- Aortic valve in 25% of cases
- Tricuspid valve / pulmonary valves - uncommon
- Fibrous bridging of valvular commissures & calcification
- “FISH MOUTH” or “buttonhole” stenoses
What is the aetiology of rheumatic fever?
- Antibodies directed against the M proteins of streptococci
- Cross-react with self antigens in the heart
- CD4+ T cells specific for streptococcal peptides
- React with self proteins in the heart
- Produce cytokines that activate macrophages (e.g. Aschoff bodies)
What are the possible causes of pericarditis?
- Inflammation of the pericardial sac can be caused by…..
- Viruses (Coxsackie B), bacteria, TB, fungi, parasites
- Immunologically mediated processes
- Rheumatic fever, SLE, scleroderma, post-cardiotomy
- Late post-MI = Dressler’s, drug hypersensitivity
- Miscellaneous conditions
- Post-MI (early), uraemia, cardiac surgery, neoplasia
- Trauma, radiation
What are the features of acute pericarditis?
- Serofibrinous / fibrinous
- Purulent / suppurative
What are the features of chronic pericarditis?
- Adhesive mediastinopericarditis
- Constrictive pericarditis
What is serous pericarditis?
Inflammation causes serous fluid accumulation in pericardium.
What is usually the cause of serous pericarditis?
- Caused by non-infectious aetiologies (generally)
- Inflammation in adjacent structures can cause pericardial reaction
- Rarely by viral pericarditis (Coxsackie B / echovirus)
- Immunologically mediated processes
- Rheumatic fever, SLE, scleroderma
- Miscellaneous conditions
- Uraemia, neoplasia, radiation
What is Dressler's syndrome?
Secondary pericarditis - AKA – Post-MI syndrome
Clinical triad of…..
2. Pleuritic chest pain
3. Pericardial effusion
What is the cause of Dressler's syndrome?
Autoimmune reaction to antigens released following myocardial infarction
NOT acute pericarditis
What is the cause of purulant/suppurative pericarditis?
What are the features of purulent/suppurative pericarditis?
- Red, granular, exudate i.e. pus (can be upto 500mls!)
- Inflammation can extend causing mediastino-pericarditis
What is the outcome of purulant/suppurative endocarditis?
Complete resolution is rare
- Restrictive pericarditis
What is haemmorhagic pericarditis?
Blood mixed with serous (watery) or suppurative (pus) effusion
What are the common causes of haemorrhagic pericarditis?
- Neoplasia (malignant cells in effusion)
- Infections (in TB/fungal preicarditis is caseous)
- Following cardiac surgery -> cardiac tamponade
What are the different forms of chronic pericarditis?
- Adhesive mediastinopericarditis
What are the features of adhesive pericarditis?
Fibrosis / stringy adhesions obliterates pericardial cavity
What are the features of adhesive mediastinopericarditis?
- Follows pericarditis caused by infections, surgery or radiation
- Obliterated pericardial cavity with adherence to surrounding structures
- Causes cardiac hypertrophy / cardiac dilation
What are the features of constrictive pericarditis?
- Heart encased in fibrous scar – limits cardiac function
- Treated by surgery to remove ‘shell’ around heart
What are the broad clinical features of pericarditis?
- Sharp central chest pain…characteristics?
- Exacerbated by : movement, respiration, laying flat
- Relieved : sitting forwards
- Radiating : shoulders / neck
- Differentials : angina, pleurisy
- Pericardial friction rub
- Loudest with diaphragm, left sternal edge
- Fever, leucocytosis, lymphocytosis, pericardial effusion
- Complications – pericardial effusion / cardiac tamponade
What is cardiomyopathy?
Literally 'heart muscle disease'?
What are the four types of cardiomyopathy?
- Arrythmogenic right venticular
What are the pathological features of dilated cardiomyopathy?
- Progressive dilation -> contractile (systolic) dysfunction
- Heart enlarged, heavy, flabby (dilation of chambers)
- Myocyte hypertrophy with fibrosis
What are the causes of dilated cardiomyopathy?
- 20 – 50% cases
- Autosomal dominant (mainly)
- Cytoskeletal proteins gene mutation
Alcohol and other toxins
- thiamine def
What are the clinical features of dilated cardiomyopathy?
Any age but commonly 20 – 50
Slow progressive signs / symptoms of
- poor exertional capacity
What is the 5 year survival for dilated cardiomyopathy?
~ 25% (like the ejection fraction!)
Death due to
- arrhythmia / embolism (intra-cardiac thrombus)
What is the treatment for dilated cardiomyopathy?
Long-term ventricular assist (can induce regression)
What is hypertrophic cardiomyopathy?
Defined by myocardial hypertrophy
Poorly compliant (stiff) left ventricular myocardium
Diastolic dysfunction with preserved systolic function
Intermittent ventricular outflow obstruction (1/3 cases)
Thick-walled, heavy, and hyper-contracting
Main cause of unexplained LVH
(in the absence of any obvious cause)
What is the aetiology of hypertrophic cardiomyopathy?
- Mutations sarcomeric proteins
- Can be sporadic
What are the clinical features of hypertrophic cardiomyopathy?
- Impaired diastolic filling - reduced chamber size / compliance of hypertrophied left ventricle
Obstruction to the left ventricular outflow
- 25% of patients
Exertional dyspnoea due to above
Systolic ejection murmur
- Ventricular outflow obstruction
- Anterior mitral leaflet moves toward the ventricular septum during systole.
What are the complications of hypertrophic cardiomyopathy?
Mural thrombus formation -> embolization / stroke
Sudden death, especially in some affected families
- Most common causes of sudden death in athletes
What is the treatment of hypertropic cardiomyopathy?
Decrease heart rate and contractility - β-adrenergic blockers.
Reduction of the mass of the septum, which relieves the outflow tract obstruction
What is restrictive cardiomyopathy?
Primary decrease in ventricular compliance
- Impaired ventricular filling during diastole
Idiopathic or secondary (infiltration)
- metastatic tumors
- deposition of
metabolites (inborn errors of metabolism)
What is the morphology of restrictive cardiomyopathy?
- Ventricles normal size / slightly enlarged chambers normal
- Myocardium is firm and noncompliant
What is arrythmogenic right ventricular cardiomyopathy?
AKA arrhythmogenic R.V. dysplasia
Genetic disease (A.D.), ~1 in 5000
RV dilation / myocardial thinning
Fibrofatty replacement of RV
Disorder of cell-cell desmosomes
Exercise -> cells detach and die
Silent, syncope, chest pain, palpitations
Sudden cardiac death – young / exercise
What are the most common causes of infective endocarditis?
Coxsackie A&B viruses
- most common cause in West
Chagas disease (Trypanosoma cruzi) protozoa
- important non-viral cause (endemic in South America)
- 10% die acutely
What are the broad clinical features of infective endocarditis?
Heart failure, arrhythmias and sudden death
Non-specific symptoms - fatigue, dyspnea, palpitations, precordial discomfort, and fever
Can mimic acute MI
DCM can develop
What are the other viral causes of infective endocarditis?
What are the bacterial causes of infective endocarditis?
What are the fungal causes of infective endocarditis?
What are the protozoan causes of infective endocarditis?
Trypanosoma cruzi (Chagas disease)
What are the helminths that can cause infective endocarditis?
What are the immune-mediated causes of myocarditis?
Post-Strep (grp A) - rheumatic fever
What are the other causes of myocarditis?
Giant cell myocarditis
What is vasculitis?
Inflammation of the vessel walls
How is vasculitis classified?
Chapel Hill Classification
By size first
Small vessel then split to ANCA/non-ANCA
What is the most common form of vasculitis?
Giant cell arteritis
- elderly individuals in the west
What is the pathology of giant cell arteritis?
Chronic granulomatous inflammation
Large to medium-sized arteries
Esp. in the head (e.g. temporal arteries
- AKA temporal arteritis)
Also vertebral and ophthalmic arteries
Ophthalmic arterial involvement
- Permanent blindness
- Giant-cell arteritis is a medical emergency requiring prompt recognition and treatment – early recognition is VITAL!
Also occurs in other vessels the aorta (giant-cell aortitis).
What is the morphology of giant cell arteritis?
- reduces the lumenal diameter
Med. granulomatous inflammation
- elastic lamina fragmentation
Multinucleated giant cells
- 75% of adequately biopsied
How is giant cell arteritis diagnosed?
biopsy and histologic
- Segmental disease
- Hence 2- to 3-cm length of artery
What is the treatment of giant cell arteritis?
- Corticosteroids is generally effective
- anti-TNF therapy in refractory cases
What is an aneurysm?
Localised, permanent, abnormal dilatations of a blood vessel
How can aneurysms be classified?
What are atherosclerotic aneurysms?
Most common, often in the elderly
Commonly - AAA secondary to atherosclerosis
How are atherosclerotic aneurysms detected?
What are the complications of atherosclerotic aneurysms?
Rupture causing retroperitoneal haemorrhage
Embolisation causing limb ischaemia
What is a dissecting aneurysm?
Tear in the wall
Blood tracks between intimal and medial layers
What are the classical features of a dissecting aneurysm?
Tearing pain in chest radiating to upper left shoulder
What are the pathological features of dissecting aneurysms?
Usually thoracic aorta secondary to systemic hypertension
Progressive vascular occlusion and haemopericardium
↑↑ Mortality without treatment (aim to reduce arterial pressure / surgery)
What are berry aneurysms?
Small, saccular lesions that develop in the Circle of Willis
Develop at sites of medial weakness at arterial bifurcations
Commonly found in young hypertensive patients
subarachnoid haemorrhage (SAH)
What are Charcot-Bouchard aneurysms?
Occur in intracerebral capillaries in hypertensive disease
Causes intracerebral haemorrhage (i.e. stroke)
What are microaneurysms?
Retinal microaneurysms can develop in diabetes causing diabetic retinopathy
What are mycotic aneurysms?
Weakening of arterial wall secondary to bacterial / fungal infection
Organisms enter media from the vasa vasorum
SBE is the most common underlying infection
Often in the cerebral arteries
Infection of AAAs risk rupture
What is a false aneurysm?
Blood filled space around a vessel, usually following traumatic rupture or perforating injury
The adventitial fibrous tissue contains the haematoma
Commonly seen following femoral artery puncture during angiography / angioplasty