Lecture 3: Cardiovascular Infections Flashcards
Endocarditis is an infection of the
valves
Fluid around the heart protects the heart from
infection
Risk factors for endocarditis
1) bacteremia (IV drug users, intravenous catheters) AND 2) structural heart disease (prosthetic valve, severe stenosis or regurg)
Endocarditis pathogens: subacute
Indolent lasts days to weeks. Strep viridians an dstrep bovis. Colonize in the nasopharynx and gums, nasophaynx procedures –> blood –> heart valves. seen in pairs and in chains.
Endocarditis pathogens: acute
Staph aureus. In IV drug users or IV devices, very fast. +cocci in clusters = staph
s/s strep spp endocarditis
subacute onset of low grade fever, fatigue and murmur due to slow valve destruction
s/s staph aureas endocarditis
acute onset high grade fever, shaking, chills and murmur due to rapid valve destruction
Valve vegetation
leads to valve destruction and systemic embolism. Comprised of a loose collection of fibrin, bacteria, platelets, and red blood cells together. –> s/s CHF and regurgitation d/t destroyed valve. Tricuspid is the first effected –> lung PEs and septic PE
Endocarditis presentation
fever/night sweats and new or worsening murmur (destroyed valves), s/s systemic emboli
Embolic phenomena of endocarditis- right sided valves
Lung emboli (presents as pneumonia)
Embolic phenomena of endocarditis- left sided valves
Embolic stroke MI Retinal emboli (Roth spots) Renal emboli (embolic damage, hematuria, renal failure) Janeway lesions Osler nodes Splinter hemorrhages
test for diagnosing endocarditis- blood culture
initial test (95% sensitive). Necessary to establish the diagnosis
test for diagnosing endocarditis- TTE
Initial imaging test. 60-70% sensitivity for vegetations. Visualization of vegetations is necessary for diagnosis. Negative TTE will require to perform TEE
test for diagnosing endocarditis- TEE
useful for establishing diagnosis if initial TTE is negative. 95%-100% sensitive. Maybe initial test for patients with prosthetic valve
ECG useful for diagnosing endocarditis?
No. Non-specific changes. Do not require for diagnosis
How do you establish the diagnosis of endocarditis?
positive blood cultures + vegetation on echo = endocarditis
How do you establish the diagnosis of endocarditis if blood cultures are negative?
(risk factors + embolic phenomene) + vegetation on echo= endocarditis
Recommended treatment for endocarditis?
Empiric coverage with intravenous Vancomycin (staph spp. including MRSA) + Ampicillin (strep spp.). Gentamycin can be added for synergism (4-6 weeks of abx)
- can be changed based on sensitivity when culture gets back
- may need surgery for ruptured valve and embolism (large vegetations)
Who needs prophylaxis abx for endocarditis?
high risk patients undergoing high risk procedures AKA significant valvular defect + high risk of bacteremia (need to have both to justify giving prophylaxis)
What counts as having significant valvular defects?
- Prosthetic valve
- Previous endocarditis
- Unrepaired/ partially repaired cyanotic defect (Tetralogy of Fallot)
who/ what procedures are at high risk for bacteremia?
- Dental work w/blood (extractions, root canal, dental cleaning)
- Respiratory tract procedures w/ blood (biopsy , tonsillectomy)
If patient should get prophylaxis, what is recommended treatment?
Amoxicillin or Clindamycin (single dose before the procedure)
what is pericarditis?
Infection/inflammation of pericardium
what are causes of pericarditis?
*Idiopathic
*Infection (viral- Coxckievirus)
Autoimmune disorders (Lupus)
Malignancy (Hodgkin lymphoma, lung cancer)
Metabolic causes (uremia)
Trauma (chest trauma)
clinical presentations of pericarditis?
- Positional (relieved by sitting forward) and pleuritic chest pain
- Friction rub (disappears with pericardial effusion)
tests for pericarditis- ECG
Initial test. Done to r/o myocardial ischemia. ECG maybe non-specific in pericarditis or show diffused ST elevations and PR depressions
tests for pericarditis- echo
To r/o pericardial effusion and tamponade. Pericarditis w/o effusion- normal ECHO
tests for pericarditis- inflammatory markers
Non-specific, likely elevated
tests for pericarditis- viral cultures
Rarely change the treatment
tests for pericarditis- chest xray
will be normal
what is the recommended treatment for pericarditis?
NSAIDs w/ or w/o Colchicine
Steroids if insufficient response to NSAIDs
Resolves in 2-6 weeks
how can you tell if a murmur is innocent?
NO STRUCTURAL PATHOLOGY Grade 1-3 (no thrill !) Always systolic (mid or early systolic) Gets softer w/ standing/Valsalva No radiation beyond precordium Always asymptomatic !!! Common in children and young adults. In older adults innocent murmurs are extremely rare
how can you tell if there is a pathologic murmur?
Diastolic, holosystolic or continuous
Grade >3
Radiating beyond the precordium
Associated with symptoms
what is hpertrophic obstructive cardiomyopathy (HOCM)? causes?
Causes: autosomal dominant genetic
Dynamic outflow obstruction during systole
grading of murmurs
Grade 1- faint (S1 and S2 is louder than a murmur)
Grade 2 - quiet (S1 and S2 = murmur)
Grade 3 – moderately loud (murmur is louder than S1 and S2)
Grade 4 – loud with palpable thrill
Grade 5 – very loud, with thrill. Maybe heard with a stethoscope is partly off the chest
Grade 6- very loud, with thrill. Maybe heard with a stethoscope entirely off the chest
what is S1 & S2? listen with what?
auscultate with the diaphragm
S1= Beginning of the systole (closure of the mitral valve)
S2= Beginning of the diastole (closure of the aortic valve)
S3, S4 (extra-sounds) – listen with?
auscultate with the bell
S3 can be heard in?
Can be heard in volume overload CHF (systolic dysfunction)
Also in young adults
S4 can be heard in?
Can be heard in decreased compliance of the ventricle in long-standing hypertension (diastolic dysfunction)
Also in older adults (common)
In systole- what are each of the valves doing?
aortic valve open, mitral valve closed
In diastole- what are each of the valves doing?
mitral valve open, aortic valve closed
HOCM s/s
Syncope during exercise
Sudden death
Harsh systolic murmur radiates to carotid, heard best at right /left sternal border
Murmur gets louder with standing/Valsalva
what should you do if a pt has an innocent murmur?
observe and re-evaluate
what should you do if a pt has a pathological murmur?
evaluate (TTE first)
Transthoracic ECHO»_space;> trans-esophageal ECHO»_space;> cardiac catheterization
