Endocarditis Flashcards
Infective Endocarditis is infection of?
cardiac valves and/or the endocardium
vegetation ( result of Infective Endocarditis) is formed by
mass of thrombus, necrotic debris and micro-organisms
Vegetation of IE is mostly on which side of the heart?
Left(on valve leaflets, mostly aortic and mitral valves.)
Right IE is caused by(unusual)
IV drugs ( unsterile material use infects the blood which goes back from circulation to right side of heart)
IE types and which one is more dangerous
1-Acute( more severe with 50% death )
2-subacute which can’t be treated but antibiotics
Which organism causes IE
*ACUTE( High virulent staphylococcus)
*SUBACUTE(Low virulent hemolytic streptococcus)
Which type of IE affects normal valves not just deformed
Acute
Hematogenous infection is caused by?
*Intravenous drug abusers
*Previous dental, surgical or interventional procedure .
Occult source of bacteremia
Small injuries to skin or mucosal surfaces.
Risk Factors of IE
1Cardiac abnormalities
•.Prostheticheartvalves(10%to20%).
(Previous two referee to deformed valve mostly)
3.Intravenousdrugabusers
Most common pathogen causing IE
-Hemolytic (viridans) streptococci (50-60%)
*attacks deformed valves(subacute)
Major cause of IE in drug abuse
Staphylococcus aureus (10-20%)
attacks healthy or deformed valves(acute)
Which organism infects prosthetic valves
Coagulase-negative staphylococci (S.epidermidis)
Percent of culture-negative endocarditis
10% No organism is isolated from the blood
Gross of vegetation in IE
Friable,bulky,and potentially
destructive
* may lead to embolism
What is (ring abscess)
When vegetation erodes into the underlying myocardium to produce an abscess cavity
Abscesses development at the sites where emboli lodge leads to
septic infarcts and mycotic aneurysms.
most consistent sign of IE
Fever ( cause it’s infection)
Clinical sign present in 90% of patients with left- sided lesions
Murmur
Diagnosis of IE is done through
Positive blood cultures and echocardiographic findings.
Microemboli ( sign of IE)can give rise to:
-Petechia
- Nail bed (splinter) hemorrhages
-Retinalhemorrhages(Rothspots)
- Painless palm or sole erythematous lesions (Janeway lesions)
- Painful fingertip nodules (Osler nodes)
Complications of IE
• Glomerulonephritis
• Arrhythmias
• Systemic embolization
Deposition in Nonbacterial Thrombotic Endocarditis consists of?
•Deposition of small (1 to 5 mm in diameter) thrombotic masses composed mainly of fibrin and platelets on previously normal cardiac valves.
Marantic endocarditis definition
Nonbacterial Thrombotic Endocarditis subtype that Occur in a wide variety of diseases associated with general wasting disease ( like cancer)
usual precursor of NBTE
Hypercoagulable states
The difference in emboli between IE and NBTE
In IE it’s septic ( more dangerous cause it froms abscess)
Thrombotic vegetation location is described as
Nearly complete row of thrombotic vegetations along the line of closure of the mitral valve leaflets.
When Systemic lupus erythematoses ( autoimmune diseases) affects heart valve it results in which disease
Libman-Sacks Endocarditis
Location of vegetation in LSE
Canoccuranywhereonthevalve surface, on the cords, or even on the atrial or ventricular endocardium
Vegetation in rheumatic heart disease morphology:
row of small vegetations along the lines of closure of the valve leaflets.
Vegetation morphology in IE
large, irregular masses on the valve cusps that extend onto the cords.
Majority of myocarditis cases are caused by
Coxsackieviruses A and B and other enteroviruses.
Can myocarditis be caused by influenza virus?
Yes
None viral myocarditis is caused by
1-protozoan Trypanosoma cruzi
2-Toxoplasma gondii
3-Trichinosis
4-Borrelia burgdorferi (bacterial spirochete)
Borrelia burgdorferi (bacterial spirochete) causes which disease
Lyme
the most common helminthic disease with associated cardiac involvement is
Trichinosis
protozoan Trypanosoma cruzi is the agent of
Chagas disease.
Noninfectious causes of myocarditis:
-Lesions associated with systemic diseases of immune origin: systemic lupus erythematosus and polymyositis.
-Drug hypersensitivity reactions(hypersensitivity myocarditis)-eosinophilia is noticed
Hypersensitivity myocarditis under microscope looks like
Interstitial and perivascular infiltrates composed of high proportion of eosinophils.
- Chagas myocarditis under microscope
Intracellular organisms (Trypanosoma cruzi) inside a myocyte
• Accompanied by an inflammatory infiltrate of neutrophils, lymphocytes, macrophages, and occasional eosinophils
Morphology of inflammatory involvement in myocarditis
Patchy
End result of surviving acute myocarditis
lesions can resolve without significant sequelae or heal by progressive fibrosis.
Heart appearance in myocarditis
Normal or dilated
Edema, myocyte injury,diffuse lymphocytic infiltrate
Are seen in
Active myocarditis
In hypersensitivity myocarditis the Interstitial and perivascular infiltrates composed of
high proportion of eosinophils.
Which microorganism is seen in chags myocarditis
Intracellular organisms (Trypanosoma cruzi) inside a myocyte
*** Accompanied by an inflammatory infiltrate of neutrophils, lymphocytes, macrophages, and occasional eosinophils
