Endo/pericarditis Flashcards
(26 cards)
What happens with a narrowed or restricted valve?
Leaflets are thickened and stiff from calcification, fibrosis, inflammation or congenital abnormalities
What does increased resistance to blood flow require?
Requires heart to pump harder
What does valvular stenosis lead to?
Leads to hypertrophy and impaired function
What does valvular stenosis most commonly affect?
the aortic and mitral valves
What happens during valvular regurgitation?
leaflets do not close properly
blood leaks backward across the valve
volume overload
chamber dilation and remodeling
dec cardiac output
What are key features of stenosis?
valve narrowing
inc pressure gradient
left ventricular or atrial ypertrophy
dec cardiac output
What are key features of regurgitation?
backward flow of blood
inc volume in the affected chamber
chamber dilation
What is endocarditis?
inflammation of innermost layer of heart (endometrium)
What is endocarditis often a result of?
bacteremia causing an infection that colonizes on the valve
What is endocarditis characterized by?
vegetations (fibrin, platelets, bacteria, on heart valves)
What is endocarditis rarely caused by?
fungus or aseptic
What valve is most commonly affected in endocarditis?
mitral valve
What is the order of the valves affected in endocarditis?
mitral > aortic > tricuspid > pulmonic
What is the exception of IV drug users with the valve affected in endocarditis?
tricuspid valve
What are risk factors of endocarditis?
IV drug use
chronic rheumatic heart dz
chronic hemodialysis
HIV +
poor dentition
intra cardiac devices
iatrogenic infection
inc >60 yo
inc in male sex
prosthetic valves- greatest first 6-12 mo
What is the most common overall cause of endocarditis?
Staph aureus
What causes subacute endocarditis?
Strep viridans: oral/dental flora (poor dentition)
What are the types of endocarditis?
Acute bacterial endocarditis
-infxn of normal valves with a virulent organism (Staph)
-febrile illness that rapidly damages cardiac structures, leads to death w/in weeks
-m/c valve affected: mitral
Subacute bacterial endocarditis
-infxn of abnormal valves with less virulent organism (Strep)
Endocarditis in IV drug users
-MRSA, Pseudomonas, Candida
-M/c valve affected: tricuspid
Prosthetic valve endocarditis
<60 days after surgical post-op valve implant
How do damaged heart valves cause endocarditis?
“sticky” surface for bacteria to attach
catheters, electrodes/leads, intracardiac prosthetic devices
chronic inflammation –> autoimmune and degenerative valve dz
What are causative agents of endocarditis?
bacteremia
-IV drug abuse
-central catheter/PICC line
-can come from gut (GI source)
-recent dental procedure
If the cardiac valve tissue has no blood supply…
it has an inability to mount an immune response and fight infection
What is the patho of endocarditis?
endothelial injury occurs and leads to altered flow –> leads to direct infection of heart or thrombus
organisms enter blood stream- organisms proliferate and cause inc coagulation, forming vegetations
leads to direct damage of cardiac structures, embolization, and hematogenous spread
What are the sx of endocarditis?
non-specific: cytokine release
-malaise
-fatigue
-night sweats
-weight loss
-weakness
What are the sx of endocarditis in an IV drug user?
usually tricuspid
faint or no murmur
pulmonary findings- cough, pleuritic chest pain, nodular infiltrates can come from septic pulm emboli that arise from tricuspid valve, FEVER, lack of peripheral lesions
