Endocarditis Flashcards
There are 3 layers of the heart wall, describe each
- EPICARDIUM = Outer Layer, Visceral Pericardium
- MYOCARDIUM = Middle Layer, Makes up majority of the heart mass
- ENDOCARDIUM = Inner Layer, Lines the chambers, valves, & vessels
how does IE occur?
when bacteria enters the bloodstream and lodges onto a heart valve, esp those with prior damage or turbulent blood flow
what is a common contributor to the etiology of IE? examples?
oral source
Dental extraction, periodontal surgery, tooth brushing, chewing candy
other causes of bacteremia besides the main one?
IV drug use, EGD, colonoscopy, TURP, IV catheters
The localization of infection is partly determined by ?
the production of turbulent blood flow
what type of IE is MC, when is it not?
Left-sided IE is more common, except among IVDU
MC pathogen to cause native valve endocarditis
Staph aureus; Streptococcus is next
Valve/Heart disorders that increase risk for IE:
- Rheumatic valvular disease
- Congenital heart disease – PDA, VSD, tetralogy of Fallot
- MVP with MR
- Degenerative heart disease, AS due to bicuspid AV, Marfan syndrome
Common causes/types of endocarditis
- Prosthetic Valve Endocarditis
- IV Drug User Endocarditis
- Native Valve Endocarditis
- Nosocomial/Healthcare-associated Endocarditis
- Fungal Endocarditis
MC pathogenetic cause of Prosthetic Valve Endocarditis
- Staphylococci (coagulase-negative and coagulase-positive) - early (within 2 months)
- Streptococci - Late (>2months)
MC pathogenetic cause of IV Drug User Endocarditis? where is the infection MC?
- Staph aureus is the MC causative organism
- Streptococci (viridans) and enterococci are next most frequent
- Tricuspid valve
leading causes of Nosocomial/Healthcare-associated Endocarditis
Central and peripheral IV catheters, pacemakers and ICDs, HD shunts, and permacaths
MC pathogenetic cause of nosocomial/healthcare-associated endocarditis
G+ cocci - S. aureus, enterococci, nonenterococcal streptococci
what type of endocarditis is More commonly found in IVDU and ICU patients who receive broad-spectrum abx
Fungal Endocarditis
complications with endocarditis
- Rupture of valve tissue or chordal structures, leading to valvular regurgitation
- Vegetation may obstruct the valve orifice or create a large embolus
- Conduction system affected by myocardial abscess
- Infection may invade the interventricular septum, causing intramyocardial abscesses or septal rupture
- Septic systemic and pulmonary emboli
MCC of death in pts with IE
Heart Failure
Presentation of IE
- within 2 wks - 6 months
- sx of systemic infection, emboli, or other complications (CHF)
- MC fever (90%), chills, weakness, shortness of breath, night sweats, loss of appetite and weight loss
- MSK sx, such as back pain, are common
- heart murmurs (80%)
- CHF is present in up to 2/3 of cases
- Septic emboli
- Pulmonary emboli
- Systemic emboli