Module 6 CVS continued: Endocarditis and Rheumatic fever Flashcards
What is Rheumatic Fever?
Active, immunologically-mediated, multisystem inflammation disease
When does Rheumatic fever occur?
Occurs few weeks after episode of rheumatogenic group A streptococcal pharyngitis (strep pyogenes)
(occurs in about 3% of strep patients and usually in 3rd world countries)
In Rheumatic fever what would you find in the heart, kidneys and joints?
Heart: Abs bind to M proteins in heart = type 2 HSR
Joints and Kidneys: Immune complexes in joints and kidneys = Type 3 HSR
called antigenic mimicry or cross reacting antibodies (trying to trick the immune system)
What test would you do for detection of Rheumatic fever?
Anti-streptolysin O test (ASO) or DNAase B
- -streptolysin O: bacterial enzyme that causes beta hemolysis
- –ASO Abs indicate past/present infection
What is the pathogenesis for Rheumatic fever?
Exact is unknown
- -type 2 HSR induced by group A strep
- –Abs directed against the M proteins of group A strep cross react with normal proteins present in heart, joints, and other tissues
How do you diagnosis Jones Criteria?
Presence of either 2 major or 1 major and 2 minor
with Evidence of preceding strep infection by increased serum ASO titers or positive strep throat culture or DNAase B
What are the major manifestations of Rheumatic fever?
ACCNE: Pancarditis Migratory polyarthritis of large joints Subcutaneous nodules Erythema marginatum of skin Sydenham chorea: involuntary, purposeless rapid movements
What are the minor manifestations of Rheumatic fever?
Fever
Arthralgia: joint pain
Rapid movements
Acute Rheumatic fever is prominent where?
In developing countries in children 10-15 years
How is acute rheumatic fever contracted?
Repeated S. pyogenes pharyngitis — type II HSR
(cross reacting antibodies to M proteins of S. pyogenes cross reacting with antigens of valves and joints — molecular mimicry
What is pancarditis?
Inflammation changes in ALL 3 layers of the heart
What is acute rheumatic myocarditis?
Central zone of degraded, hypereosinophilic ECM with lymphocytes and macrophages
Aschoff bodies (this is the whole complex): around arteries (perivascular) and granuloma like (Combination of CD4+ lymphocytes and activated macrophages/Anitshkow cells) and aschoff cells
myocarditis leads to arrhythmia’s
What are anitschkow cells?
Nuclei look like owls eye on transverse section; caterpillar; appearance on longitudinal section
What is acute rheumatic pericarditis?
Fibrinous pericarditis (Bread and butter) -- friction rub (worse on reclining and relieved when sitting up) remember that pericarditis is ST elevation and normal cardiac enzymes
What is acute rheumatic endocarditis?
Regurgitation of mitral valve
Pansystolic murmur loudest at apex
Sterile vegetation’s with fibrin because organism there — verrucae endocarditis —- regurgitation
(look a vegetations on google..straight line)
What titers do you find in the blood for Acute Rheumatic fever?
ASO and DNAase B titer in blood
What is the etiology for chronic rheumatic heart disease?
STEM WILL SAY IMMIGRANT
Recurrent attacks of rheumatic fever
takes many years for this to develop– which leads to fibrosis and stenosis of cardiac valves
What are the complications of chronic rheumatic heart disease?
- Left atrial enlargement —- failure — pulmonary edema — less than 2 weeks transudate —- more then 2 weeks fibrosis and hemosiderin laden macrophages —- pul HTN — right heart failure —- nutmeg liver
- Heart failure —- stasis — mural thrombosis —- left atrium (LE or brain) (legs always first because its left side of heart)
- Dental work —- strep. viridens —- subacute endocarditis (only affects damaged valves) — embolizes and septic emboli — organism travels with emboli — LE (gangrene) and brain (liquefactive from the get go)
- –ppl with chronic rheumatic fever need to get put on ABX before dental procedures
Upon fibrosis of the mitral valve there is fishmouth/buttonhole appearance, describe the the fibrosis in chronic rheumatic heart disease
Irregular thickening and calcification of the leaflets, with fusion of the commissures and the chordae tendinae
What murmurs would you find on a patient with chronic rheumatic heart disease?
Systolic and diastolic murmur
because mitral reg before you get stenosis and atrial valves (may be affected) can be affected
In chronic rheumatic fever when the left atrium enlarges due to mitral valve stenosis (Compresses central structures), what happens?
Mass effect!
Trachea: SOB
Esophagus: dysphagia
Left recurrent laryngeal nerve: hoarseness
(note this is the same mass effect as thoracic or syphilis aneurysm)
In chronic rheumatic fever, what happens when you have a damaged mitral valve?
Superimposed infective endocarditis
What investigation would you do for chronic rheumatic heart disease?
Echo – look for fibrosis of heart valves
What is calcific aortic stenosis?
Narrowing of the aortic valve lumen as a result of deposition of Ca2+ in the cusps and valve ring
–remember this is dystrophic calcification from wear and tear — can shear RBCs — produce schistocytes (helmet cells); jaundice (bilirubin you get is unconjugated)
What is the presentation for aortic stenosis ?
Usually in patients over 60 years old
Patients in their 40s —-Congenital bicuspid aortic valve – occurs earlier in life and usually patients with TURNERs (Short stature, webbing of neck and streak ovaries, infertility or wide spacing of nipples or horseshoe kidney)
SAD (syncope, angina,dyspnea)
–remember turners patients may also have coarctation of the aorta
What are the complications of aortic stenosis?
- Left ventricular hypertrophy: increased protein synthesis or decreased protein degradation
- Left heart failure —pulmonary edema — pulmonary HTN —- right heart failure (transudate until 2 weeks and after 2 weeks fibrosis and hemosiderin laden macrophages)
- Decreased stroke volume and decreased cardiac output: less supply and increased demand, ischemia and infarction of myocardium (MI)
- Mural thrombus + Arrhythmia - embolic stroke
- Aortic valve is damaged — infective subacute endocarditis (S. viridans) (note this will be from dental work)
What is the investigation for Aortic Stenosis?
ECHO —- left ventricular hypertrophy (which makes sense because blood is not getting through that aortic valve from the LV to the aorta)
If an elderly person presents with disorientation and difficulty speaking, weakness and nodular deposits near mitral valve, what is the dx?
Aortic Stenosis
What is the presentation for mitral valve prolapse?
Young women between 20 & 40
Marfan’s syndrome or Ehler’s Danlos Syndrome or polycystic kidney disease
Asymptomatic and incidental finding of mild systolic click
What is the pathogenesis for mitral valve prolapse?
Accumulation of GAGs or proteoglycans or ground substance or mucopolysaccharides in spongiosa layer (myoxid degeneration of valve)
What are the complications of mitral valve prolapse?
Rupture of chordae tendinae – mitral regurgitation – left heart failure — all blood is getting dumped into lungs via pul veins — pulmonary edema
(pansystolic murmur at apex) (midstolic click)
Abnormal mitral valve + dental work = bacteremia due to S. viridans (subacute infective endocarditis)
What do you see on histology for mitral valve prolapse?
Movat’s Pentachrome Stain: myxomatus degeneration
–expansion of spingosa layer: excessive amount of loose, edematous, faintly basophilic ground substance in valve - weakening of CT if mitral valve — ballooning
What are the three layers in histological slide for mitral valve?
Ventricle Fibrosa (collagen) Spongiosa (mucopolysaccharides) Atrialis (elastic) Atria
Quick review: explain the difference in cordae tendineae in rheumatic carditis vs mitral valve prolapse
Thicken and fused: Rheumatic carditis
Thin, elongated and fragile: mitral valve prolapse
What is infective endocarditis?
Infection of cardiac valves or mural surfaces of endocardium — resulting in formation of adherent, bulky mass of thrombotic debris and organisms— vegetations
There are two types of infective endocarditis, acute and subacute endocarditis. each card will highlight some differences. Explain the differences in symptoms?
Acute: High fever, no splenomegaly and no finger clubbing
Sub-acute: low grade fever, splenomegaly and finger clubbing
What are the different bacterias for acute vs subacute endocarditis?
Acute: staph. aureus in normal valves (likes left side of heart) — death
Sub acute: S. viridans in abnormal valves: good prognosis with prophylactic antibiotics (HACEK group: hemophilus, actinobacillus, cardiobacterium, eikenella and Kingella) show negative blood cultures
What are the difference in vegetations for acute and subacute endocarditis?
Acute (Normal valves): Large vegetations with minimal neutrophils because valves are avascular (bacterial colonies and fibrin)
Sub-Acute (affects both): Small vegetations, granulation tissue, fibrosis, plasma cells, macrophages, and fibroblasts (dystrophic calcification)
What are the different conditions leading to acute vs subacute endocarditis?
Acute: IVDA using dirty needles — tricuspid valve – causes splinter hemorrhages under fingernails (S. aureus)
Sub acute: Syphilis, rheumatic heart disease, calcification of mitral valve and mitral valve prolapse
— abnormal valve + dental work: bacteremia due to S. Viridans (HACEK: look this up)
What are the complications you see in acute vs subacute endocarditis?
Acute: Sepsis — septic emboli —- lungs — multiple lung abscesses
—ring abscess in myocardium and arrhythmias
Sub Acute: Sepsis — septic emboli — legs and brain
—glomerulonephritis – type III HSR
What kind of cells do you find in acute vs subacute endocarditis?
Acute: minimal inflammatory cells and RBCs and fibrin
Sub-acute: granulation tissue and chronic inflammatory cells (lymphocytes, plasma cells, macrophages, fibroblasts, fibrosis and dystrophic calcification)
One of the consequences of vegetation is persistent bacteremia, what are the complications of this and host consequences?
Complication: seeding of distant sites and cytokine release
Host consequence: joint, bone, organ disease. constitutional symptoms
The second consequence of vegetation is tissue destruction, what are the complication of this and host consequences?
Complication: valvular insufficiency, AV conduction and abnormalities
Host consequences: congestive heart failure ; heart blocks
The third consequence of vegetation is fragmentation, what are the complications of this and host consequence?
Complication: peripheral emboli
Host consequence: CNS emboli and stroke, MI, splenic or kidney infarct, mycotic aneurysm, splinter hemorrhages (nails)(only in acute), Janeway lesions (palms and soles), Roth spots ( retinal hemorrhages) and Osler nodes (subQ nodules in pulp of digits)
The last consequence of vegetation is release of bacterial antigen, what are the complications and host consequences?
Complication: immune complex formation
Host consequences: Glomerulonephritis
Review: What is the most common cause of viral myocarditis?
Coxsackie Virus (not rheumatic fever)
Review: where do you see verrucae endocarditis?
Rheumatic fever
wart like vegetations and they are sterile: all antibody mediated and found along line of closure and affects mitral, aortic and tricuspid valves
Review: what does endocarditis leads to?
Regurgitations so if its mitral regurgitation then this is pansystolic murmur loudest at the apex (blood is going back to the left atrium — so goes back into pulmonary veins and hence you get pulmonary edema)
Review: what valves are affected in chronic and acute rheumatic fever?
MAT
mitral, aortic, tricuspid
Review: In chronic rheumatic fever the second most common valve affected is the aortic valve and you get stenosis because of fibrosis and on top of this you get dystrophic calcification. so how on gross image can you distinguish an aortic valve in chronic rheumatic fever from calcified aortic stenosis?
Chronic Rheumatic Fever: Fusion of commissure fissure and chordae tendinea
Calcified aortic stenosis: no fusion of commissure fissure
(make sure to note the difference on the pics in lab)
Review: what is an additional way to differentiate rheumatic fever and calcified aortic stenosis?
Affects mitral first then aortic in Chronic Rheumatic Fever
Review: what is the most common cause of left ventricular hypertrophy?
Systemic HTN
not aortic stenosis
Review: what scenarios give you schistocytes and jaundice (From unconjugated bilirubin)?
- Aortic Stenosis
- Microangiopathic hemolytic Anemia (MAHA)
- Metallic Prostatic Valve
- DIC
What investigations are done for infective endocarditis?
Serial blood cultures to identify the organism
Echo to see the vegetations
What is the presentation in both acute and subacute endocarditis?
Fever (inflammation)
Murmur (Endocarditis causes regurgitation)
If the stem states a patient who is an known IVD user who has acute infective endocarditis also has a right to left shunt has an emboli, what kind of emboli will this patient have?
Paradoxial (Bypasses lungs and goes first to LE and then to brain)
but if no left to right shunt then the tricuspid valve is affected and therefore the lungs are affected
What criteria is used for Infective endocarditis?
DUKE CRITERIA
What is the location of the vegetations in infective endocarditis?
Large, irregular masses on the valve cusps that can extend on the chordae (look at pic on google)
What is the location of the vegetations in acute rheumatic fever?
Along the lines of closure of the valve leaflets (mostly affects mitral valve)
