Infective endocarditis Heart Disease Braunwald CV R4 李威廷醫師 Supervisor: 李貽恆醫師

Infective endocarditis

Heart Disease

Braunwald

CV R4 李威廷醫師Supervisor: 李貽恆醫師

Infective endocarditis

Definition: • Microbial infection of the endothelial surface

Valves

Septal defect

chordae tendineae

mural endothelium

• NVE: native valve endocarditis• PVE: prosthetic valve endocarditis

Infective endocarditisIncidence: 2 / 100,000 patient-years,

15—30 / 100,000 patient-years ( >60 y/o)

• Rheumatic heart disease• Congenital heart disease• Mitral valve prolapse with regurgitation• Degenerative heart disease• Asymmetrical septal hypertrophy• Intravenous drug abuse• Prosthetic valve (7—25%)

Infective endocarditis: patient groups

• Children with IE: congenital heart disease (aortic valve),

normal structure (tricuspid valve),

Staphylococcus (neonate),

Streptococcus group B (children), S. pneumonia (rare)

• Adults with IE: redundancy, thickened leaflets, >45 y/o

MVP + MR: 52 / 100,000 patient-years

Rheumatic heart disease: MV (F>M), AV (M>F)

Congenital heart disease: PDA, VSD, bicuspid AV

Infective endocarditis: patient groups• IV drug abusers with IE: 5.3—6400 / 100,000 patient-years,

TV (46—78%) MV (24—32%) AV (8—19%)

S. aureus, GNB (Pseudomonas), polymicrobial

S/S: pleuritic chest pain, SOB, cough, hemoptysis,

HIV: 73%; increased mortality (CD4 < 200)

• Prosthetic valves with IE: greater incidence post 6-month valvular surgery

early (< 60 days): surgical complication,

late (> 60 days): community or nosocomial

ring abscess, annular invasion, paravalvular regurgitation

Infective endocarditis: nosocomial

• Infected intracardiac device and catheter• GI or GU tract surgery or instrumentation• High mortality (40—56%)

• GPC ( S. aureus, CONS, Enterococcus)• S. aureus catheter related bacteremia (23%): TEE

Infective endocarditis: microorganism

• Streptococcus viridans: 35 — 65% NVE

normal inhabitants of the oropharynx

penicillin sensitive

penicillin plus aminoglycoside

S. bovis: colon polyp or malignancy

Group A streptococcus: drug abuser, tricuspid valve

Group B streptococcus: systemic emboli

Group G streptococcus:


• Streptococcus pneumoniae: alcoholism

aortic valve

concurrent pneumonia or meningitis

Penicillin / Rocephin Vancomycin

• Enterococcus: normal GI tract flora and cause GU infection

5—15% NVE and PVE

resistant to Oxacillin

Penicillin / Ampicillin / Vancomycin / Teicoplanin + GM


• Staphylococcus: Coagulase-positive: S. aureus highly toxic febrile

30—50% CNS involvement

Mortality: 16—46% (L’t), 2—4% (R’t)

Oxacillin / 1st cephalosporin

Coagulase-negative: S epidermidis Major cause of PVE

community-acquired: Oxacillin sensitive

nosocomial infection: Oxacillin resistant


• Gram negative bacteria: upper respiratory tract and oropharyngeal flora

B/C incubation 3 weeks

P. aeruginosa: most common in GNB IE HACEK: haemophilus spp., Actinobacillus actinomycetemcomitans,

Cardiobacterium hominis, Eikenella corrodens, Kingella

kingae

• Fungus: drug abuser and post valve replacement

common: C. albicans (PVE); C. parapsilosis (NVE)

Infective endocarditis: pathogenesis

• Vascular endothelial reaction

• Hemostatic mechanism

• Host immune system

• Gross anatomic abnormalities

• Surface property of microorganism

• Initial bacteremia

Infective endocarditis: pathogenesis

• Nonbacterial thrombotic endocarditis (NBTE) Malignancy, DIC, uremia, burn, SLE, valvular heart disease,

and intracardiac catheter

Atrial side of MV/ TV, and ventricular side of AV/ PV:

(1) high velocity jet

(2) flow from a high to a low pressure chamber

(3) flow across a narrow orifice (Venturi’s effect)

• Infective endocarditis (IE) specific mucosal surfaces and skin, density of colonizing bacteria,

and the extent of local trauma, esp. oral mucosa

Dextran (streptococcus), fibronectin (S. aureus, S. viridans)

Infective endocarditis: pathophysiology

• Local destruction of intracardiac infection: valve, chordae tendineae, fistula, paravalvular abscess, conduction

• Distant embolization with infarct or infection: 45—65% (autopsy), 70% pulmonary embolism in R’t IE

• Hematogenous seeding with bacteremia: metasttic infection,

• Immune-complex or antibody reaction: IgM, IgA, IgG, Osler’s node, Rheumatoid factor, Roth’s spot

Infective endocarditis: clinic• Fever: most common

• Heat murmur: 80—85%

• CHF: valve destruction, chordae tendon rupture, intracardic fistula

• Enlargement of spleen: 15—50%

• Petechiae: most common peripheral sign

• Splinter or subungual homorrhages, Osler’s nodes, Janeway’s lesions, Roth’s spots

Infective endocarditis: clinic

• Myalgia, arthralgia, back pain

• Systemic emboli• Neurological: 30—40%, embolic stroke (most common),

mycotic aneurysm,

• Renal insufficiency: imm8une-complex mediated glomerulonephritis (azotemia); embolic renal infarct (hematuria)

Infective endocarditis: diagnosis

• Duke criteria:

Major criteria: B/C, echogram

Minor criteria: predisposition, fever vascular phenomenon,

microbiological evidence, echogram

TEE (sensitivity: 82—94%)


• Anemia: normochromic, low Fe, low TIBC

• Leukocytosis• ESR (erythrocyte sedmentation rate): elevation except

in congestive heart failure, renal failure and DIC

• Thrombocytopenia: rare

• CRP, RF, immune complex, cryoprotein• U/A: protenuria and microscopic hematuria (50%)


• Echocardiography should not be used as a screening test for IE in unselective patients with positive blood cultures or in patients with fever of unknown origins when clinical probability is low

• Echocardiography should be performed in all patients with clinically suspected IC, including those with negative blood cultures

• TEE: diagnosis, IE complication and follow up

• TEE: sensitivity ( 82—94%) both in NVE and PVE

• TTE: sensitivity ( <65%); specificity ( = 100%) in NVE

sensitivity (16—36%) in PVE

• Thickened valve, ruptured valve or chordae, calcification, nodules

Infective endocarditis: treatment

• Eradication

• 109 to 1010 organisms per gram of tissue

• Bactericidal, parenteral• MIC: minimum inhibition concentration

• MBC: minimum bactericidal concentration

• Tolerance: MBC > 10x MIC• Synergy


• Streptococcus viridans or bovis in NVE penicillin sensitive: Aq penicillin 2-3MU q4h x4wks

or Rocephin 2g qd x4wks

or Vancomycin 15mg/kg q12h x4wks

or

(Aq + GM 1mg/kg q8h) x2wks

(uncomplicated condition)

• Streptococcus viridans or bovis in PVE Aq penicillin 2-3MU q4h x6wks

plus GM 1mg/kg q8h x2wks


• Streptococcus viridans or bovis in NVE penicillin resistant (MIC= 0.2—0.5)

Aq penicillin 3MU q4h x4wks

or Rocephin 2g qd x4wks

or Vancomycin 15mg/kg q12h x4wks

plus

GM 1mg/kg q8h x2wks

penicillin resistant (MIC >0.5): as enterococcus protocol


• S. pyogens, pneumoniae, group B, C, G penicillin sensitive: Aq penicillin 3MU q4h x4wks GM 1mg/kg q8h x2wks before MIC & penicillin resistant (MIC >0.1): Rocephin 2g qd + Vancomycin 15mg/kg q12h x4wks GM 1mg/kg q8h x2wks

early surgery for cardiac complications

Infective endocarditis: treatment• Enterococcus Aq penicillin 3-5MU q4h x4-6wks

or Ampicillin 2g q4h x4-6wks

or Vancomycin 15mg/kg q12h x4-6wks

plus

GM 1mg/kg q8h x4-6wks

Gentamicin resistant, prevent nephrotoxicity, ototoxicity

Cephalosporin is not alternative therapy

Early surgery if high resistant to Penicillin / Ampicillin / Vancomycin


• Staphylococcus with NVE OSSA: Oxacillin 2g q4h x4-6 wks (2wks *)

or Cefazolin 2g q8h x4-6wks

plus

GM 1mg/kg q8h x3-5 days

or Vancomycin 15mg/kg q12h x4-6wks

ORSA: Vancomycin 15mg/kg q12h x4-6wks


• Staphylococcus with PVE OSSA: Oxacillin 2g q4h >=6wks

plus

Rifampin 300mg po q8h >=6wks

plus

GM 1mg/kg q8h x2wks

ORSA: Vancomycin 15mg/kg q12h x4-6wks

plus Rifampin

plus GM


• HACEK group: Rocephin 2g qd x4wks

or Ampicillin 2g q4h x4wks

plus

GM 1mg/kg q8h x4wks

• Pseudomonas aeruginosa: Ticarcillin / Piperacillin plus GM


• Culture-negative NVE Ampicillin 2g q4h x4-6wks

or Rocephin 2g qd x4-6wks

plus

GM 1mg/kg q8h x4-6 wks

• Culture-negative PVE Ampicillin / Rocephin + GM

plus Vancomycin 15mg/kg q12h x4-6wks


• Outpatient: response to initial therapy and free of fever

not experiencing threatening complications

good drug compliance

general condition evaluation

• Monitor treatment: 33% adverse effect of beta-lactam patients,

(Oxacillin and Ampicillin)

fever, rash, neutropenia, mean =15 days

Infective endocarditis• Extracardiac complications

Splenic abscess: percutaneous needle aspiration for diagnosis

drainage for successful treatment

Mycotic aneurysm and septic arteritis: cerebral cortex, middle cerebral artery branches

septic embolite with secondary arteritis: S. aureus

bacterial seeding: Streptococcus viridans

Infective endocarditis: prevention• NBTE X IE• Streptococcus viridans: esophagus, respiratory

tract, oral mucosa

• Enterococcus: GI and GU tract

• Staphylococcus aureus: skin

Retrospective study, cost-benefit 55-75% patients did not know cardiac lesion till IE

5% IE patients knew cardiac lesion and recent procedure with

prophylaxis

penicillin-resistant bacteria due to other antibiotics prophylaxis

Infective endocarditis prevention

• High risk procedure: Dental: high- and moderate- risk group

Non-dental : high risk group

• MVP without murmur: not prophylaxis, but risk slightly increase

IE prophylaxis • High risk:

normal population:

(pre-30 min) Ampicillin 2g IV/IM + GM 1.5mg/kg

(post-6 hour) Ampicillin 1g IV/IM

or Amoxicillin 1g po

penicillin allergy: (pre-30 min) Vancomycin 1g IVD + GM 1.5mg/kg

(post-6 hour) no second dose

IE prophylaxis • Moderate risk:

normal population:

(pre-1 hour) Amoxicillin 2g po

or (pre-30 min) Ampicillin 2g IV/IM

penicillin allergy: (pre-30 min) Vancomycin 1g IVD

(post-6 hour) no second dose

Documents

Infective endocarditis Heart Disease Braunwald CV R4 李威廷醫師 Supervisor: 李貽恆醫師