Endocarditis Flashcards
What are the two etiologies of endocarditis
- infective (microbial) –> destroys the valve tissue and you get thrombosis and microbes within the vegetation
- non-infective (non microbial)
- verrucous (rheumatic fever)
- atypical (SLE)
- thrombotic-like (marantic)
- verrucous (rheumatic fever)
Contrast subacute and acute in :
- course
- organism
- valve integrity
- symptoms
- valve destruction
- weeks-months v days
- S. viridans (non virulent) v S. aureus (virulent)
- prior damage to valve v a prior normal valve
- insidious (malaise, fever low-grarde v abrupt (fever, chills, ill)
- mild-moderate v severe
Give the step by step patho of infective endocarditis
- Form non-bacterial thrombotic endocarditis, causing turbulent flow and endothelial damage (resulting in deposits of platelet-fibrin thrombi)
- transient bacteremia results due to mucosal trauma and bacteria released
- bacteria adhere via adhesins/agglutiinins, localizing to the high flow, low pressure side
- vegetation forms here (fibrin, platelets, red cells, bacteria)
- metabolically inactive bacteria can proliferate at these vegetations states
What further conditions can these vegetations bring?
- sustained bacteremia (fever/fatigue)
- direct valve damage (MR/AR/TR, and eventually heart failure)
- emboli
- circulating immune complexes
What are the two most common symptoms?
fever, then chills and sweats
name most common signs of endocarditis
fever
heart murmur
new/worsened murmur
embolic phenomoneon
if a murmur is new/present what type is it typically?
- regurgitant murmur
3 cardiac manifestations of endocarditis
- murmurs
- myocardial abscess formation at the septum/valve ring
- mycotic aneurysm (BACTERIAL) via peripheral arterial invasion
What are the three main non-cardiac areas of body affected by Endocarditis
- cutaneous
- ophthalmic
- cerebral
What are the three main cutaneious manifestations and what are tehy?
- osler nodes (PAINFUL) via deposits of immune complexes
- janeway lesions (PAINLESS) via septic emboli
- splinter hemorrhages (red-brown streaks on fingernails/toenails
2 main ophthalmic manifestations
- petechiae (red spots on conjuctiva because of hemorrhage via broken capillaries
- roth spots (retinal lessions)
Main cerebral manifestation… what condition puts endocarditis on the differential
- mycotic aneurysm
- stroke
WHAT ARE LAB MANIFESTATIONS of endocarditis
- anemia (via hemolysis during chronic disease)
- leukocytosis (not as high elevated WB, but still elevated)
- elevated ESR/CRP
- proteinuria (if kidney is affected)
how to diagnose endocarditis
if positive, what does it tell yoU?
- blood cultures
3 sets in first 24 hours (more if you’ve taken antibiotics given in 2 weeks
- hold in lab for >21 days for completeness
if positive, only tells you for sure you have bacteremia
- use echocardiography to identify vegetations, characterize them, and identify complications
What is the duke major criteria for endocarditis
- positive blood cultures
2. endocardial involvement seen via regurgitant murmur or echo showing vegetation
what echo method should be used to view vegetation
TEE
Name 3 complications of IE
- direct valve destruction
- local extenstion
- peripiheral embolization
Name 4 sources of bacteremia
- Oral cavity/skin/Upper respiratory (S. viridans, staphylococci, groiup b strep, Hacek group)
- GI tract (S. bovis)
- Urinary tract (enterococci)
- Health care setting (foleys for sure): S. aureus, enterococci
what is the HACEK group
Haemophilus species
Actinobacillius actinomycetemcomitans
Cardiobacterium hominis
Eikenella corrodens
Kingella kingae
What endocarditis does IV drug users do?
Tricuspid valve endocarditis (S aureus)
What microorganism causes endocarditis in prosthetic valves
- Staph epidermidis
What microorganism would cause endo in GI disease
S. bovis
What microorganism would cause endo in young women/old men
S. enterococcus
What microorganism would cause endo in those with abnormal valves?
- S. viridans
Classically, acute endocarditis in IV drug users would be due to ______ affecting the _____ valve
- S. aureus
- tricuspid
why in general are left sided endocarditis cases seen more often
- this is the high pressure side, which is where microorganisms tend to localize in these areas
For prosthetic heart valves..
what microorganism are you worried about <12 months after? > 12 months after? in gneral, what is the time period of your highest risk?
What valve is more likely to get endo in this case, aortic or mitral?
- S. epidermis
- coag neg staph
<6 months is worst risk
SAME incidence rate between aortic and mitral (both left sided)
What are etiologic factors of culture negative endocarditis
- previous antibiotic therapy that causes elusion of blood cultures
- fastidious, slow growing orgnaisms
- shitty microbiological techniques (culture)
What are agents of culture negative endo
prognosis if still febril > 1 wk
- bartonella, C burnettii
50 percent survival
What children are most susceptible and have high mortality of endo
- premies w/ s. aureus and cyanotic congenital lesions (tetrology)
What is NBTE endocaridtis
what part of heart does and types (mechanical v prosthetic) does it affect
what physiological state is it associated with?
marantic
- sterile, non-destructive vegetations
- usually native valves (neither prosthetic nor mechanical)
- hypercoagulable state
Who is at highest risk of endocarditis? lowest/absent?
Highest:
- CHD
- prior CV surgery with device insertion
- IVDA/eldelrly/immnosuppressed
- prior episoode of endo
- transplants with valvulopathy
Low: ASD (no pressure gradient anymore)
what are 4 principles of therapy
- bactericidal agents
- IV administration
- long duration
- prepare for relapse
Name 5 surgical indications
- refractory HF (severe valve dysfunciton)
- > 1 serious embolic episode
s - uncontrolled infection (persistent fever/bacteremia)
- lack of effective abx
- MOST prosthetic valves (can’t clear infection with just medicine because of access)
