carditis Flashcards
inflammation of the heart muscle
myocarditis
most commonly affected in IE
heart valves
how does IE occur
when bacteria and occasionally fungi and other
microbes enter the bloodstream & attack the lining of
the heart or the heart valves
how does IE cause a leaky valve
there are vegetations or holes on valves or scarring of the valve tissue that may result in a leaky valve
Intracardiac effects include severe valvular
insufficiency, which may lead to:
- intractable congestive heart failure
- myocardial abscesses (foci of infection
prototypic lesion of IE
vegetation
what are vegetations
mass of platelets, fibrin, microcolonies of mcg and scant InFtory cells
Febrile illness that rapidly damages cardiac
structures
acute endocarditis
what is mycotic aneurism
ballooning of blood vessel due to bacteria
bacteria that cause acute endocarditis
S aureus
bacteria that cause subacute endocarditis
S. viridans
this usually occurs w/o ill effects but usually leads to IE in patients w/
an underlying CV lesion or w/ a suppressed immune
system
transient bacteremia
HACEK
Haemophilus Actinobacillus Cardiobacteria Eikenella Kingella
this causes Q fever
Coxiella burnetti
most common cause of early prosthetic valve infections
Staphylococci
how does NBTE develop?
Endothelial cells that line the inside of the heart and the
heart valve can become damaged leading to the
accumulation of platelets or uninfected platelet-fibrin
thrombus producing a condition called non-bacterial
thrombotic endocarditis (NBTE)
conditions which lead to endothelial cell damage
RHD CHD MVP Degenerative HD Prosthetic valve replacement
where does bacteria and platelets accumulate to produce NBTE
downstream or low-pressure side of valvular lesion
this help bacteria colonize NBTE
Surface adherence factors
this binds to platelet receptors
Strep sanguis
this binds to fibronectin
S aureus
where does S sanguis bind
platelet receptors
where does S aureus bind
fibronectin
four outcomes in the formation of vegetations
- damage to intracardiac structures
- embolization of vegetation fragments
- Hematogenous infection of sites during bacteremia
- Tissue injury due to the deposition of circulating
immune complexes or immune responses to
deposited bacterial antigens
the symptoms of acute IE is similar to the presence of what
abscess
which has a rapid onset of symptoms (acute or subacute)
acute
most common symptom of subacute IE
low grade fever
manifestations seen in both types of endocarditis
murmurs roth spots petechial hemorrhages janeway lesions osler nodes
changing murmur occurs when
valve leaflet is destroyed or chordae tendinae ruptures
murmurs are less common in ____
R-sided endocarditis
these are retinal hemorrhages with pale centers
roth spots or flame shaped hemorrhages
Painless hemorrhagic plaques on the palms and
soles
janeway lesions
Small, pea-sized subcutaneous, painful
erythematous nodules that occur in the pads of the
fingers and toes and the thenar eminence
osler nodes
In IE lab results, peripheral leukocyte count is not normal in what conditions
myocardial abscess formation
extravascular site infection
acute endocarditis
test for the confirmation of IE
2D echo
what are the findings in the chest x-ray in IE
distinct round cannonball like pulmo emboli in R-sided endocarditis
1 do you need to do an hourly blood culture at different sites of the body
to rule out transient bacteremia which lasts abt 30 min
doppler color flow allows assessment of
valve function
myocardial contractility
chamber volume
Definite endocarditis accdg to duke criteria
2 major
1 maj 3 min
5 min
possible endocarditis accdg to duke criteria
1 maj 1 min
3 min
therapy for IE must be
bactericidal and given for long periods
High risk cardiac lesions for which endocarditis prophylaxis is advised before dental procedure
prosthetic HV prior endocarditis unrepaired cyanotic CHD completely repaired CHD valvulopathy after cardiac transplant
most important infectious agent for myocarditis
viruses
single most important group of viruses for myocarditis
enteroviruses
bacterial causes of myocarditis
legionella chlamydia
borrelia
burgdorferi
fungal causes of myocarditis
aspergillus
caandida
cryptococcus
parasitic causes of myocarditis
trypanosoma cruzi
trichinella spiralis
before the heart effects are seen in myocarditis what is usually the manifestation
skin infection
if the pericardium is involved this sign may be present
friction rub
ekg in myocarditis may present
ST and T wave changes, vent or atrial arrhythmias
conduction defects
why echo is used in the diagnosis fo myocarditis
assess cardiac contractility,
chamber size, valve function and wall thickness
why contrast enhanced MRI is used in the diagnosis fo myocarditi
detect the extent and degree of IFN
determine parameters that correlate with LV function
contraindicated in the treatment of myocarditis
Glucocorticosteroids and immunosuppresive drugs
treatment for fulminant disease
cardiac transplant
