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

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

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

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;345:1318-1330

PRESENTING SYMPTOMS OF IE Fever 80% Anorexia 75% Chills 40% Dyspnea 40% Weight Loss 25% Night Sweats 25% Myalgia/Arthralgia 15% Adapted from Mandell et al. 2000 (Karmpaliotis) 2008 Zoll Firm Lecture Series

Zoll Firm Lecture Series PRESENTING SIGNS OF IE Fever 90% Heart murmur 85% Changing murmur 5-10% New murmur 3-5% Peripheral manifestations 50% Petechiae 20-40% Splinter hemorrhages 15% Osler nodes 10-20% Janeway lesions <10% Splenomegaly 20-50% Septic complications 20% Clubbing 10-50% Adapted from Mandell et al. 2000 (Karmpaliotis) 2008 Zoll Firm Lecture Series

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

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

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

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

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

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

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

Zoll Firm Lecture Series Surgical Indications CHF – strongest indication Mortality in medically treated patients = 56-86% vs. 11-35% 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

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

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

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