infective endocarditis heart disease braunwald cv r4 李威廷醫師 supervisor: 李貽恆醫師
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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:
Infective endocarditis: microorganism
• 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
Infective endocarditis: microorganism
• 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
Infective endocarditis: microorganism
• 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%)
Infective endocarditis: diagnosis
• 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%)
Infective endocarditis: diagnosis
• 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
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• HACEK group: Rocephin 2g qd x4wks
or Ampicillin 2g q4h x4wks
plus
GM 1mg/kg q8h x4wks
• Pseudomonas aeruginosa: Ticarcillin / Piperacillin plus GM
Infective endocarditis: treatment
• 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
Infective endocarditis: treatment
• 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