Download Endocarditis

Endocarditis
Jim Czarnecki, D.O.
Internal Medicine Lecture Series
Introduction
Background
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Defined as an infection of the endocardial
surface of the heart, which may include one or
more heart valves, the mural endocardium, or a
septal defect.
Three types:
Native valve (acute and subacute)
 Prosthetic valve (early and late)
 Related to intravenous drug use
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Native Valve
Endocarditis
Native Valve Endocarditis
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Usually has an aggressive course
Typical causative agents are Staphlococcus aureus
and group B streptococci.
Underlying structural valve disease may not be
present.
Subacute endocarditis usually has a more
indolent course than the acute form.
Native Valve Endocarditis
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Alpha-hemolytic streptococci or enterococci,
usually in the setting of underlying structural
valve disease, typically are the causative agents
of this type of endocarditis.
Prosthetic Valve
Endocarditis
Prosthetic Valve Endocarditis
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Early prosthetic valve endocarditis occurs within
60 days of valve implantation.
Staphylococci, gram-negative bacilli, and
Candida species are the common infecting
organisms.
Prosthetic Valve Endocarditis
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Late prosthetic valve endocarditis occurs 60 days
or more after valve implantation.
Alpha-hemolytic streptococci, enterococci, and
staphylococci are the common causative
organisms.
Endocarditis and IV
Drug Use
Endocarditis and IV Drug Use
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Commonly involves the tricuspid valve.
S. aureus is the most common causative
organism.
Pathophysiology
Pathophysiology
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Infective endocarditis generally occurs as a
consequence of nonbacterial thrombotic
endocarditis, which results from turbulence or
trauma to the endothelial surface of the heart
Transient bacteremia then leads to seeding of
lesions with adherent bacteria, and infective
endocarditis develops.
Pathophysiology
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Pathologic effects due to infection can include
local tissue destruction and embolic phenomena.
Secondary autoimmune effects, such as immune
complex glomerulonephritis and vasculitis, can
occur.
Frequency
Frequency
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In the US: Incidence is 1.4 to 4.2 cases per
100,000 people per year.
Internationally: Incidence of disease appears to
be similar throughout the developed world.
Mortality / Morbidity
Mortality / Morbidity
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Increased mortality rates are associated with:
Increased age
 Infection involving the aortic valve
 Development of congestive heart failure
 Central nervous system (CNS) complications
 Underlying disease
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Mortality rates also vary with the infecting
organism.
Mortality / Morbidity
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Mortality rates in native valve disease range from
16-27%
Mortality rates in patients with prosthetic valve
infections are higher.
More than 50% of these infections occur within
2 months after surgery.
Gender / Age
Gender / Age
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Gender:
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The male-to-female ratio is approximately 2:1
Age:
Can occur at any age
 Mean age of patients has gradually risen over the
past 50 years
 Currently, more than 50% of patients are older than
50 years of age.
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Clinical Aspects
History
History
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Present illness history is highly variable.
Symptoms are commonly:
Vague
 Emphasize constitutional complaints
 May focus on primary cardiac effects
 Secondary embolic phenomena
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History
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May present with signs of congestive heart
failure (due to valvular insufficiency)
Secondary phenomena could include focal
neurological complaints due to:
Embolic stroke
 Back pain associated with vertebral osteomyelitis
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Fever and chills are the most common
symptoms.
History (Other)
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Other common
complaints include:
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Anorexia
Weight loss
Malaise
Headache
Myalgias
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Additional common
complaints include:
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Night sweats
Shortness of breath
Cough
Joint pains
Physical
Physical
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Fever, either low-grade or intermittent, is present in
90% of patients.
Heart murmurs are heard in approximately 85% of
patients.
Signs of neurologic disease occur in as many as 40% of
patients.
Embolic stroke with focal neurologic deficits is the
most common etiology. Others can be intracerebral
hemorrhage and multiple microabscesses.
Physical
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Signs of systemic septic emboli are due to left
heart disease and are more commonly associated
with mitral valve vegetations.
Multiple congestive heart failure signs, such as
distended neck veins, are frequently due to acute
left-sided valvular insufficiency.
Physical
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Classic signs of infective endocarditis are found in as
many as 50% of patients. They include:
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Petechiae – common by nonspecific finding
Splinter hemorrhages – dark red linear lesions in the
nailbeds
Osler nodes – Tender subcuaneous nodules usually found
on the distal pads of the digits
Janeway lesions – Nontender maculae on the palms and
soles
Roth spots – Retinal hemorrhages with small, clear centers;
rare and observed in only 5% of patients.
Petechiae
Splinter Hemorrhages
Osler Nodes
Osler Nodes
Janeway lesions
Roth Spots
Physical (Other)
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Other findings:
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Splenomegaly
Stiff neck
Delirium
Paralysis
Hemiparesis
Aphasia
Conjunctival hemorrhage
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Additional findings:
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Pallor
Gallops
Rales
Cardiac arrhythmia
Pericardial rub
Pleural friction rub
Causes
Causes: Native Valve
Causes: Native Valve
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Rheumatic valvular disease (30%) – primarily
involves the mitral valve followed by the aortic
valve.
Congenital heart disease (15%) – include patent
ductus arteriosus, ventricular septal defect,
tetralogy of Fallot
Mitral valve prolapse with associated murmur
(20%)
Causes: Native Valve
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Degenerative heart disease – includes calcific
aortic stenosis due to bicuspid valve, Marfan
syndrome, or syphilitic disease
Approximately 70% of cases are caused by
Streptococcus species including Streptococcus
viridans, Streptococcus bovis, and enterococci.
Staphlococcus species cause 25% of cases and
generally demonstrate a more aggressitve acute
course.
Causes: Prosthetic Valve
Causes: Prosthetic Valve
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Early disease, presenting shortly after surgery,
has a different bacteriology and prognosis than
late disease, which presents in a subacute fashion
similar to native valve endocarditis.
Infection associated with aortic valve prostheses
is particularly associated with local abscess and
fistula formation.
This may lead to heart block, shunting of blood
to the right atrium, or pericardial tamponade.
Causes: Prosthetic Valve
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Endocarditis can occur in association with
intravascular devices.
Infection that occurs early after surgery may be
caused by a variety of pathogens, including S.
aureus and S. epidermidis.
Late disease is most commonly caused by
streptococci.
Causes: IV Drug Use
Causes: IV Drug Use
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Most commonly involves the tricuspid valve,
followed by the aortic valve.
Two thirds of patients have no previous history
of heart disease and no murmur on admission.
Diagnosis of endocarditis in intravenous drug
users can be difficult and requires a high index
of suspicion.
Causes: IV Drug Use
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S. aureus is the most common (<50% of cases)
etiologic organism. Other causative organisms
include streptococci, fungi, and gram-negative
rods (eg. Pseudomonads, Serratia species).
Causes: Fungal Endocarditis
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Found in intravenous drug users and intensive
care unit patients who receive broad-spectrum
antibiotics.
Blood cultures are often negative, and diagnosis
frequently is made after microscopic
examination of large emboli.
Causes: Diagnosis
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Usually made using Duke Criteria (link is on IM
website). Major criteria include:
Multiple positive blood cultures for the infecting
organism
 Echocardiographic evidence of endocardial
involvement or a new regurgitant murmur on
physical examination
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Differentials
Differentials
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Connective tissue disease
Fever of unknown origin
Intra-abdominal infections
Septic pulmonary infection
Tricuspid regurgitation
Workup
Lab Studies
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Send baseline studies:
CBC
 Electrolytes
 Creatinine
 BUN
 Glucose
 Coagulation Panel
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Lab Studies
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Two sets of blood cultures have greater than
90% sensitivity when bacteremia is present.
Anemia of chronic disease is common in
subacute endocarditis
ESR, while not specific, is elevated in more than
90% of cases.
Proteinuria and microscopic hematuria are
present in approximately 50% of cases.
Lab Studies
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Leukocytosis is observed in acute endocarditis
Anemia is present in subacute endocarditis.
Rheumatoid factor is noted in subacute
endocarditis.
Serology for Chlamydia, Q fever (Coxiella), and
Bartonella may be useful in culture-negative
endocarditis.
Imaging Studies
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Echocardiography
Transthoracic echocardiography has a sensitivity
of approximately 60%.
Transesophageal echocardiography has a
sensitivity of more than 90% for valvular
lesions.
Both techniques are highly specific for valvular
vegetations.
Vegetation on Mitral Valve
Imaging Studies
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Imaging studies are particularly indicated with culturenegative cases, such as in fungal endocarditis.
Echocardiography is highly useful to assess local
complications, such as abscesses.
Chest radiography: Pulmonary embolic phenomena
strongly suggest tricuspid disease.
Ventilation/perfusion (V/Q) scanning: This may be
useful in right-sided endocarditis.
CT scanning: helpful in localizing abscesses.
Imaging Studies
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EKG:
Nonspecific changes are common
 First-degree AV block and new interventricular
conduction delays may signal septal involvement in
aortic valve disease; both are poor prognostic signs.
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Cardiac catheterization – indicated to determine
the degree of valvular damage.
Treatment
Treatment
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Focus is on making the correct diagnosis and
stabilizing the patient with acute disease and
cardiovascular instability
Most cases the etiologic microbial agent is not
known
General recommendations: three (3) sets of
blood cultures over a few hours, and then
empiric antibiotic therapy may be administered.
Treatment
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General Measures:
Treatment of congestive heart failure
 Oxygen
 Hemodialysis (may be required in patients with renal
failure)
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Consultations:
Cardiology
 Cardiothoracic Surgery Service
 Infectious Diseases Service
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Medication
Medication
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Empiric antibiotic therapy is chosen based on
the most likely infecting organism.
Native valve disease usually is treated with
penicillin G and gentamicin for synergistic
treatment of streptococci.
Patients with history of IV drug use – treated
with nafcillin and gentamicin to cover
methicillin-sensitive straphylococci.
Medication
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Infection of a prosthetic valve may include
methicillin-resistant Staphylococcus aureus –
thus vancomycin and gentamicin may be used.
Rifampin also may be helpful in patients with
prosthetic valves or other foreign bodies;
however, it should be used in addition to
vancomycin or gentamicin.
Follow-up
Deterrence / Prevention
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Consider prophylaxis against infective
endocarditis in patients at high risk:
Presence of prosthetic heart valve
 History of endocarditis
 History of rheumatic heart disease
 Congenital heart disease with a high-pressure
gradient lesion and mitral valve prolapse with a heart
murmur
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Deterrence / Prevention
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The presence of coronary artery stenting is not
considered to place the patient at high risk for
endocarditis.
Deterrence / Prevention
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Consider prophylaxis in patients before they
undergo procedures that may cause transient
bacteremia, such as:
Ear, nose, and throat (ENT) procedures associated
with bleeding, including dental manipulations and
nasal packing
 Incision and drainage of an abscess
 Anoscopy and Foley catheter placement when a
urinary tract infection is present or suspected
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Complications
Complications
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Myocardial infarction, pericarditis, cardiac arrhythmia
Cardiac valvular insuffiency
Congestive heart failure
Sinus of Valsalva aneurysm
Aortic root or myocardial abscesses
Arterial emboli, infarcts, mycotic aneurysms
Arthritis, myositis
Glomerulonephritis; acute renal failure
Stroke syndromes
Mesenteric or splenic abscess or infarct
Prognosis
Prognosis
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Acute endocarditis due to S. aureus is associated
with a high mortality rate (40%), except when it
is associated with IV drug use.
Endocarditis due to streptococci has a mortality
rate of approximately 10%.
Prognosis largely depends on whether or not
complications develop.
Competency Exam
Question One
1) Signs of systemic septic emboli are associated
with:
A) Pulmonic valve vegetations
B) Mitral valve vegetations
C) Tricuspid valve vegetations
D) Aortic valve vegetations
E) All valves of the heart
Question One
1) Signs of systemic septic emboli are associated
with:
A) Pulmonic valve vegetations
B) Mitral valve vegetations
C) Tricuspid valve vegetations
D) Aortic valve vegetations
E) All valves of the heart
Question Two
2) All are true of IV drug use-induced
endocarditis, except:
A) Involves tricuspid valve
B) Involves the aortic valve
C) Can be difficult to diagnosis
D) Streptococci species is usually the etiologic
organism
E) There is usually no murmur on admission.
Question Two
2) All are true of IV drug use-induced
endocarditis, except:
A) Involves tricuspid valve
B) Involves the aortic valve
C) Can be difficult to diagnosis
D) Streptococci species is usually the etiologic
organism
E) There is usually no murmur on admission.
Question Three
3) Pulmonay embolic phenomena strongly suggest:
A) Pulmonic valve disease
B) Mitral valve disease
C) Tricuspid valve disease
D) Aortic valve disease
E) Does not involve any heart valves
Question Three
3) Pulmonay embolic phenomena strongly suggest:
A) Pulmonic valve disease
B) Mitral valve disease
C) Tricuspid valve disease
D) Aortic valve disease
E) Does not involve any heart valves
End of Lecture
Thank you for your attendance.
This lecture will be made available at
the Internal Medicine Residency
website:
http://IM.official.ws