risk factors for infective endocarditis:

Infective endocarditis Infective endocarditis: infection of the endothelium of the endocardial surfaceinner tissue of the heart- , mostly the valves ...
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Infective endocarditis Infective endocarditis: infection of the endothelium of the endocardial surfaceinner tissue of the heart- , mostly the valves but it can be anywhere where we have a septal defect. -Infective endocarditis is classified into acute and subacute according to the onset of the symptoms if a patient came with a fever for more than 2 months this is subacute and slowly endocarditis -another classification is according to the valve; native or prosthetic valve. -Infective endocarditis is uncommon -it happens more in the left side than the right and more in the prosthetic valves than the native (mostly the prosthetic valve has more severe infection ). -right sided infective endocarditis is more common in IV drug abuse –affect the tricuspid valve-, or in patient with central line, pace maker, catheter in the right side, also in HIV patient, otherwise its more in the left side.

risk factors for infective endocarditis: 1)degenerative valvular heart disease, it is almost impossible for a normal valve to be infected, because a normal valve has intact endothelium so it is a must to have endothelial injury in order to have infective endocarditis the endothelial injury can be caused by sever stenosis, regurgitation, infection, rheumatic valve, prosthetic valve. 2)poor oral hygiene(cause chronic bacteremia) 3)hemodialysis 4)IV drug abuse 5)immunocompromised

so when we talk about endothelial injury we mean that there is jet causing that injury, this jet can be due to stenosis, or due to regurgitations or others Jet

endothelial injury

platelet aggregation thrombus formation

this thrombus stays sterile until there is bacteremia –for any reason- the bacteria will infect this thrombus, where the bacteria gets away from the immune system and starts vegetating inside the thrombus. -we said before that it is a must to have endothelial injury in order to have infective endocarditis, and we also said that this endothelial injury is caused by 1 ‫الصفحة‬



Infective endocarditis jet, now in ASD the opening is large so there is less turbulence in the blood flow, there is less jet, less endothelial injury and so less infective endocarditis. while in VSD the opening is smaller so we have more turbulence in the blood flow, more jet, more endothelial injury and thus a higher risk to develop infective endocarditis keep in mind; jet turbulence endothelial injury is the cause of infective endocarditis

Bacteremia: -the American heart association 2007 gave a new guide line for prophylaxis. they found that the duration of bacteremia is more important than the volume of bacteremia. -The highest risk of bacteremia is in periodontal procedures, and if the patient already have a poor oral hygiene even chewing gum or brushing his teeth will cause him bacteremia. -aortic valve is most commonly affected. -the vegetation may be large enough to cause stenosis, or it can cause perforation, regurgitations, or even abscess which might extend to the AV node leading to heart block. -there is 2 types of prosthetic valve ; mechanical and biological (taken from pigs) the risk of getting infective endocarditis in the first 3 months is higher in mechanical valves, but after that they both have equal risk - any patient with risk of developing infective endocarditis should be given prophylaxis before any procedure mainly periodontal procedures -in the first two months of prosthetic valve procedure the most common microorganisms causing infective endocarditis are hospital acquired( esp. staph epidermdis ), after these two months it will be infected with the same bacteria infecting a native valve -Nosocomial infective endocarditis can be a result of central line, pace maker, ICD lead, dialysis catheter, hemodialysis, and mostly the invasive to the heart procedures .. (mostly staph epidermis or staph aureus ) .

microorganism in infective endocarditis: 1-the most common microorganism is strep. (strep. Viridans , alpha-hemolytic streptococci,Streptococcussanguinis , Streptococcus oralis, Streptococcus mitis) all are part of the normal flora in the mouth, strep. Bovis(gallolyticus) is part of the colon normal flora , if it was found in the culture that means there is a cancer that perforated the colon and reached the blood and the heart, here we should 2 ‫الصفحة‬



Infective endocarditis do endoscopy to roll out colonic cancer 2-enteroccocus (enterococcus faecalis ,enterococcus faecium ) after gastrointestinal procedures. 3-staph is NOW more common than strep and it is more virulence more resistance and more aggressive; staph aureus in native valve and staph epidermidis in prosthetic valve 4-gram negatives HACEK, they are fastidious organisms (the culture result is negative; they need a special culture) 5-E.coli 6-klebsiella 7-psudomonas in IV drug abusers 8-Neisseria (rare) - a culture negative endocarditis is a result of prior antibiotic administration(mostly), fastidious or fungal infection ( such as Coxiella, brucella, candida…) all need special culture -symptoms: *fever(mostly) *malaise * weakness *sweating * new murmur (added to the one the patient already has because of the defected valve) *petechial rash *this vegetation may cause a showering of emboli, which might go to the brain creating an abscess, it's called septic emboli, or it can go to retina and then Roth's spots can be seen during fundoscopy , or to the kidney causing kidney impairment. *splinter hemorrhage *splenomegaly (usually in subacute infective endocarditis) *glomerulonephritis *hematuria *proteinuria *murmur *heart block (if it reaches the AV node) *Janeway lesions: in the soles and palms, hemorrhagic, not painful caused by septic embolization *Osler's nodes : swollen, tender, palmer nods (immunological) *conjunctival bleeding

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Infective endocarditis

-presentation : Mostly fever of unknown origin for long time . -Investegation : 1-blood culture : Advisable to take 3 specimen , at least 2 .. from different locations , bcz the most common m.o are staph.aureus , staph.epidermidis , which are normal flora , so may appear in contaminated specimen .. to rule out contamination do more than one culture . if one is positive others are –ve, mostly this +ve is contamination . if the patient is stable the interval btw specimens taking should be 2 hours , if not 10 minutes is enough .. give him anti-biotic after taking the specimens . 2-echo : Best method . we have 2 types : a.Trans-thorasic :Simple , non-invasive , low sensitivity ( can't see the small vegetations , also there is ribs , muscles , lung .. that ) so –ve transthoracic doesn't rule out infective endocarditis . b.Trans-esophageal [ TEE ] : like endoscope with ultrasound camera .. insert it in the mouth , when it reaches the esophagus it will be directly behind the left atrium so the valves can be seen , even the small vegetations can be seen .. if it is –ve then it is 95% truly –ve 3-CBC 4-Esr 5-CRP 6-Rf will be +ve , bcz it is hyper immunological response 7-Mid stream urine analysis .. hematuria -diagnostic criteria : Revised Duke Clinical Diagnostic Criteria The majors : 1-+ve blood culture with typical mo ( ex. staph or strep , not Chlamydia ) 2-New valvular defect 3-vigitations The minors : 1-risk factors ; ex. already having mitral stenosis … 2-fever 3-Osler's nodes 4 ‫الصفحة‬



Infective endocarditis 4-splenomegaly 5-Janeway lesions 6-leukocytosis 7-+veRf For diagnosis u should have : 2 majors , 1 major with 3 minor or 5 minors . *false –ve culture mostly in specimens taken post Anti-biotic taken . *there is non-infectious endocarditis / immunological like SLE (Libman–Sacks endocarditis) . *complications : 1- valve stenosis 2-regurge ; acute valve regurgitation is top emergency can cause (3-) heart failure . may extend cause (4-) abscess , if on the AV node he will came with heart block 5-septic emboli , go to brain  stroke , kidney  renal impairment . *treatment : 1-the main safe treatment is Anti-biotic : Most microorganisms are resistant so start with strong Ab from the binging. IV ; vancomycin+/- gentamicin(aminoglycoside antibiotic)… with prosthetic valve or suspicion of staph epid. We Add rifampicin . Duration = 4-6 weeks . After treatment if the fever still here think of : 1- resistant mo , so go back to the culture , 2- other problems appear after the admission ( DVT , pneumonia , allergy ( vancomycin SE ) ) 2- surgery : Indicated in : 1- Perforated valve. 2-Severe Heart failure. 3-Abscess. 4-Prosthetic valve which is avascular. 5-Large vegetations ( > 1cm) ( high risk of emboli ) . 6-Fungal / pseudomonal cause . 7- heart block .

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Infective endocarditis *Mortality : depend on the organism ; higher in candida , pseudomonal than in strep . depend also on the presentation ; heart failure , not like others . also on Extension , abscess . *Prevention : In high risk : 1- prosthetic valve , prosthetic material 2-Unrepaired cyanotic heart disease 3-repaired cyanotic heart disease in the first 6 months 4-repaired cyanotic heart disease With residual defect 5-Post heart transplant with valvular heart disease In hi risk procedure ;periodontal Now .. This is the guideline but dr.Sukaina has another opinion ; because of economic and other causes she follows this: Low risk : 3g amoxicillin 1 hour pre-op… clindamycin if allergic. High risk : 2 gm IV amoxicillin 0.5 hr pre-op + 1.5 mg / kg gentamycin .. 6 hours post-op 1 gm amoxicillin If allergic : vancomycin + gentamicin 1 gm 0.5hr pre-op and 12 hrs post 1gm vancomycin

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