1. Original slides courtesy of Dr. David M. Leder
Endocarditis
Original slides courtesy of Dr. David M. Leder
2008
Zoll Firm Lecture Series

2. Infective Endocarditis
Microbial infection of the endocardial surface of the heart
Can be acute or subacute/chronic, on the basis of the tempo and severity of the clinical presentation and progression of the untreated disease
Characteristic lesion is a vegetation = collection of platelets, fibrin, microrganisms, and inflammatory cells
Most commonly involves the heart valves, but may also occur at the site of a septal defect, on the chordae tendineae, or on the mural endocardium
2008
Zoll Firm Lecture Series

3. Conditions Predisposing to IE
Structural cardiac abnormalities:
AS, AR
Bicuspid aortic valve
MS, MR
Senile mitral ring calcification
Factors altering immunity:
Immunosuppression
Diabetes
Chronic alcoholism
External factors:
Mechanical valves
Indwelling vascular catheters
Pacing wires (IV)
Factors causing bacteremia:
Dental work
IV drug use
GU/GI operations
2008
Zoll Firm Lecture Series

4. Zoll Firm Lecture Series
Microbiology
Table 1. Microbiologic Features of Native-Valve and Prosthetic-Valve Endocarditis.
2008
Zoll Firm Lecture Series
Mylonakis E and Calderwood S. N Engl J Med 2001;345:

5. PRESENTING SYMPTOMS OF IE
Fever %
Anorexia 75%
Chills %
Dyspnea 40%
Weight Loss 25%
Night Sweats 25%
Myalgia/Arthralgia 15%
Adapted from Mandell et al (Karmpaliotis)
2008
Zoll Firm Lecture Series

6. Zoll Firm Lecture Series
PRESENTING SIGNS OF IE
Fever %
Heart murmur 85%
Changing murmur 5-10%
New murmur 3-5%
Peripheral manifestations 50%
Petechiae %
Splinter hemorrhages 15%
Osler nodes %
Janeway lesions <10%
Splenomegaly %
Septic complications 20%
Clubbing %
Adapted from Mandell et al (Karmpaliotis)
2008
Zoll Firm Lecture Series

7. Common Peripheral Manifestations of Infective Endocarditis
Figure 1. Common Peripheral Manifestations of Infective Endocarditis.
Splinter hemorrhages (Panel A) are normally seen under the fingernails or toenails. They are usually linear and red for the first two to three days and brownish thereafter. Panel B shows conjunctival petechiae. Osler's nodes (Panel C) are tender, subcutaneous nodules, often in the pulp of the digits or the thenar eminence. Janeway's lesions (Panel D) are nontender erythematous, hemorrhagic, or pustular lesions, often on the palms or soles.
2008
Zoll Firm Lecture Series

8. Modified Duke Criteria for the Diagnosis of Infective Endocarditis
Three echo findings qualify as major criteria:
1. Discrete, echogenic, oscillating intracardiac mass located at a site of endocardial injury
2. A periannular abscess
3. A new dehiscence of a prosthetic valve
Table 3. Modified Duke Criteria for the Diagnosis of Infective Endocarditis.
2008
Zoll Firm Lecture Series

9. Modified Duke Criteria for the Diagnosis of Infective Endocarditis
Table 3. Modified Duke Criteria for the Diagnosis of Infective Endocarditis.
2008
Zoll Firm Lecture Series

10. Modified Duke Criteria
Definite:
2 major
1 major + 3 minor
5 minor
Possible:
1 major and 1 minor
3 minor
2008
Zoll Firm Lecture Series

11. Zoll Firm Lecture Series
Echocardiography
Transthoracic- for diagnosis
Excellent specificity, 98%
Sensitivity 60-70%
Transesophageal- for diagnosis
Sensitivity 75-95%
Specificity 85-98%
NPV >92%
In general, echocardiogram should be performed when there is a moderate- high clinical suspiciion of endocarditis
In addition to diagnosis, also useful in:
Assessing the hemodynamic severity of known IE
Assess complications (abscesses, perforation, and shunts)
2008
Zoll Firm Lecture Series

12. Cardiac Complications
CHF due to acute valvular regurgitation
More common with aortic valve (compared to MV)
Heart block
Abcess formation
Extension of IE beyond the valve annulus predicts higher mortality, more freq CHF, need for cardiac surgery
2008
Zoll Firm Lecture Series

13. Zoll Firm Lecture Series
TTE vs TEE
TTE is should be performed 1st- if the morphology and function of the valve is entirely normal, the likelihood of IE is very low.
TEE should be performed first when:
Limited transthoracic windows
Prosthetic valves (acousitc shadowing makes it very hard to evaluate endocarditis)
?S. aureus bacteremia (high virulence)
TEE should also be performed when
Surgery is contemplated
High likelihood of a paravalvular abscess- manifested by new conduction delay on EKG, persistent fever/clinical deterioration despite appropriate therapy…etc.
2008
Zoll Firm Lecture Series

14. Zoll Firm Lecture Series
Surgical Indications
CHF – strongest indication
Mortality in medically treated patients = 56-86% vs % among pts with medical/surgical therapy
Abscess
Persistent infection despite ABx
Pseudomonas, brucella, coxiella, candida, other fungal infections
S. aureus prosthetic valve IE
No size or location threshold exists which accurately predicts mortality assoc w embolization that a risk-benefit ratio can be calculated
2008
Zoll Firm Lecture Series

15. So endocarditis is bad, but can we prevent it?
2008
Zoll Firm Lecture Series

16. Iis there REALLY a benefit to prophylaxis?
Lack of any randomized, controlled clinical trials to support the application of the results of animal studies to humans.
Clinical reports of failure of antibiotic prophylaxis against endocarditis or studies that appear to show that prophylaxis is not protective.
The evidence that dental and other procedures cause endocarditis is circumstantial. With the incidence of bacteremia (positive blood culture) varying from 8% (urethral catheterization) to as high as 94% (periodontal surgery/extractions), the actual incidence of endocarditis is low (10 to 60 cases per 1 million persons per year). Studies suggest that dental treatment alone is not a risk factor for endocarditis.
In specific circumstances, such as prophylaxis for all cases of MVP, the risk of death due to penicillin is estimated to be greater than the risk of infective endocarditis.
2008
Zoll Firm Lecture Series

17. New guidelines for antibiotic prophylaxis
Now recommends antibiotic prophylaxis only to the highest risk patients, including:
Prosthetic heart valves, including bioprosthetic and homograft valves.
Previous history of IE.
Unrepaired cyanotic congenital disease, including palliative shunts conduits.
Complete repaired congenital heart disease with prosthetic device.
2008
Zoll Firm Lecture Series