Infective Endocarditis Flashcards
What are the 3 layers of the heart wall?
- Epicardium
- Myocardium
- Endocardium
What is another name for the epicardium?
Visceral pericardium
Which heart layer makes up the majority of the heart mass?
Myocardium
What heart layer lines the chambers, valves, and vessels?
Endocardium
What is the severity of infective endocarditis? What does this vary on?
Indolent illness that responds to antibiotics to life-threatening
Depends on infecting organism
How does IE occur?
- Bacteria enters bloodstream and lodges onto heart valve, especially one with prior damage or turbulent blood flow
What is the etiology of infectious endocarditis?
- Oral source
- IV drug use
- EGD
- Colonoscopy
- TURP
- IV catheters
What are possible oral sources of infectious endocarditis?
- Dental extraction
- Periodontal surgery
- Tooth brushing
- Chewing candy
What determines the location of infection?
- Production of turbulent blood flow
- Left-sided IE is more common, except among IVDU
What is the most common organism that causes native valve endocarditis?
- Staph aureus followed by streptococcus
What are valve/heart disorders that increase risk of 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
What organisms are most common in early prosthetic valve endocarditis (within 2 months)? Late?
- Staphylococci (within 2 months)
- Streptococci
What are the most common causative organisms of IV drug user endocarditis?
- Staph aureus (MC)
- streptococci and enterococci
Which valve is most commonly impacted by IV drug user endocarditis?
Tricuspid valve
What are leading causes of nosocomial/healthcare-associated endocarditis?
- Central and peripheral IV catheters
- Pacemakers and ICDs
- HD shunts
- Permacaths
What are the most common pathogens responsible for nosocomial/healthcare-associated endocarditis?
- Gram-postive cocci, such as S. aureus, enterococci, nonenterococci streptococci
Who more commonly gets fungal endocarditis?
- IV DU and ICU patients who receive broad spectrum abx
What are risk factors for endocarditis?
Cardiac
* Previous endocarditis
* Prosthetic valve or pacemaker
* Valvular or congenital heart disease
Noncardiac
* IV DU
* IV catheter
* Immunosuppression
* Recent dental or surgical procedure
What are complications of endocarditis?
- Rupture of valve tissue or chordal structures leading to valvular regurgitation
- Vegetation obstructing valve orifice or creating embolus
- Conduction system impacted by myocardial abscess
- Infection invading interventricular septum causing intramyocardial abscesses or septal rupture
- Septic systemic and pulmonary emboli possible
What is the MC cause of death in patients with IE?
Heart failure
What are symptoms of IE?
- Symptoms within 2 weeks of precipitating event or minimal for 6 months
- Symptoms related to systemic infection, emboli, or other complications, such as CHF
- FEVER (90% of IE)
- MC complaints: fever, chills, weakness, shortness of breath, night sweats, loss of appetite and weight loss
- Musculoskeletal symptoms, such as back pain
What conditions are often present due to IE?
- Heart murmurs (>80%)
- CHF (2/3)
- Septic emboli
Which etiology of endocarditis has less heart murmurs?
IVDU with TV endocarditis (1/3 of time)
What would a pulmonary emboli due to IE look like?
- pleuritic chest pain
- cough with blood-tinged sputum
- cavitating lesions on chest x-ray
septic embolic can travel through the systemic system to what arteries with IE?
- Renal
- Cerebral
- Coronary
- Mesenteric
What are physical findings of peripheral manifestations of IE?
- Petechiae
- Splinter hemorrhages
- Janeway lesions
- Osler nodes
- Roth spots
How do petechiae in IE present? What organisms are common causes of this?
- Red, non blanching lesions in crops on conjunctiva, buccal mucosa, palate, extremities
- Strep and staph
What are splinter hemorrhages? What organisms are common causes?
- Linear, red-brown streaks in nail beds
- Strep and staph
What are Janeway lesions? What is a common cause?
- Erythematous/hemorrhagic macular or nodular, painless patches on palms or soles caused by emboli
- Staph
What are Osler nodes? What is a common cause?
- Painful nodules on pads of fingers or toes caused by vasculitis
- Strep
What are roth spots? What organism is a common cause?
- Oval, pale retinal lesions surrounded by hemorrhage
- Strep
What is one of the most serious complications of IE?
- CNS embolization