Amen Corner:
Endocarditis Prophylaxis
Jimmy Klemis, MD
Cardiology Conference
April 18 2002
Amen Corner -- where the 11th green, 12th hole and 13th tee meet
at the southeast corner of Augusta National -- got its name when the
great golf writer Herbert Warren Wind observed more than 40 years
ago that a golfer who successfully negotiates it should say "Amen."
Amen Corner II – where the patient with structural heart disease, a
bacteremic-inducing procedure, and a bad outcome meet – got
its name when the lowly cardiology fellow Jimmy Klemis observed
more than 4 weeks ago that a physician who misses the opportunity
to prevent it doesn’t get to say “Amen”
Case Presentation
60 M admitted for 5 wk history of “not
feeling well”; c/o, fatigue, DOE, and
nocturnal angina. Patient states was doing
well until 1-2d after recent colonoscopy/bx
for hx heme + stools. Found to have colon
polyp, discharged to f/u with PCP.
 PMHx: CAD/LAD stent 12wk ago, HLP, hx
mild AI/AS
 Denies drug/etoh

Case Presentation
PE: T 99.8 HR 95 BP 102/62
 HNT: poor dentition, no jvd, nl carotid
pulsation
 CV: nl S1/2, +S3, no S4, 2/6 diastolic
decr m LSB, 2/6 sys m RUSB
 RESP: basilar rales
 ABD: nt/nd
 EXT: no edema

Case Presentation
Admitted for eval new CP, suspected
endocarditis – empiric Abx started, Bld Cx
4/4 + for S. viridans
 TEE: 4+AI, vegetation NCC AV, EF 60%
 Abx continued, CT surg consulted. Pt
initially hemodynamically stable and
defervesced. ~10d into hosp course pt
decompensated – tachy/hypotension/EMD
 Unsuccessful resucitation, pt died

Endocarditis
Bacteremia (daily activites, procedures,
infections)
 adherence/colonization on platelet fibrin
aggregates which have formed on valve
endothelium due to congenital or acquired
dz
 if host defenses overwhelmed 
ENDOCARDITIS

Endocarditis Prophylaxis
No randomized or controlled clinical trials
proving that antimicrobial prophylaxis prevents
IE in structurally abnl hearts after procedures
 Overall incidence of procedure-related
endocarditis is low
 However, significant literature establishing
certain hi-risk conditions more likely predisposed
to endocarditis and certain procedures which
may have higher incidence of bacteremia with
aggressive pathogens known to cause
endocarditis

Determining Risk


Cardiac conditions
Type of Procedure
Cardiac conditions which
predispose pt for IE
Based on risk of progression to severe
endocarditis with substantial morbidity
and mortality (not simply risk of
developing IE)
 Classified into

– HIGH risk
- prophylaxis
– MODERATE risk - prophylaxis
– NEGLIGIBLE risk - no prophylaxis
Cardiac Conditions – High



Prosthetic Valves (400x risk2)
Previous endocarditis
Congenital
–
–
–
–

1
Risk
Complex cyanotic dz (Tetralogy, Transposition, Single Vent)
Patent Ductus Arteriosus
VSD
Coarctation
Valvular:
– Aortic Stenosis/ Aortic Regurg
– Mitral Regurgitation
– Mitral Stenosis with Regurg

Surgically constructed systemic pulmonary shunts or
conduits
1Durack,
et al. NEJM 1995
2Steckleberg,
et al. Inf Dis Clin N Amer 1993
Mod Risk per 1997 AHA guidelines
Cardiac Conditions - Moderate Risk1

Valvular
–
–
–
–
–
–
MVP + regurg and/or thickened leaflets
pure Mitral Stenosis
TR/TS
Pulmonic Stenosis
Bicuspid AV/ Aortic Sclerosis
degenerative valve dz in eldery
Asymmetric Septal Hypertrophy/HOCM
 surgically repaired intracardiac lesions w/o
hemodynamic abnormality, < 6 mos after surg

1Durack, et al. NEJM 1995
Negligible Risk (no prophylaxis)
MVP no regurg
 Physiologic/innocent murmur
 Pacemaker/ICD
 Isolated Secundum ASD
 prev CABG
 surgical repair ASD/VSD/PDA , no residua
> 6mos after surgery

Procedures
1930’s – studies linking significant
bacteremia induced after extraction of
teeth1
 Serratia marcesens introduced as sentinal
organism shown to be present in venous
blood immediately after tooth extraction2
 incidental bacteremia also seen in control
groups, less often, less virulent

1Okell,
et al. Lancet. 1935
2Burket,
et al. J Dent Res 1937
Procedure related
1
bacteremia
Procedure related bacteremias are short lived
 highest freq + Bld Cx 30 secs after tooth
extraction
 episodes bacteremia from dental procedures
generally last < 10 min
 most pt have sxs within 1-2 wks of procedure
and can occur as early as 1-2 days; if sxs occur
later less likely procedurally related

1Durack,
et al. NEJM 1995
Procedures
Highest risk oral/dental
 Int risk GU/Pulm
 Low risk GI

1Durack,
et al. NEJM 1995
Dental/Oral Procedures
PROPHYLAXIS
 Procedures with
gingival/mucosal bleeding
 extractions, periodontal,
endodontal procedures
 professional cleaning or
scaling
 orthodontic bands







NO PROPHYLAXIS
Minimal/no bleeding
simple fillings above
gumline
Restorative dentistry*
adjustment of orthodontic
appliances
xray, injections, fluoride
treatments
*clinical judgement if potentially significant bleeding
GI/GU Procedures
PROPHYLAXIS
Esoph dilatation
 Sclerotherapy for esoph
varices
 ERCP with biliary
obstruction
 Biliary surgery
 Surgery involving
intestinal mucosa
 Prostatic Surgery
 Cystoscopy
 Ureteral dilatation


*Optional for High Risk pt
1<10
NO PROPHYLAXIS
TEE*
 Endoscopy w/wo bx*1
 Ureteral catheterization
 D&C
 “Therapeutic” Ab
 Vaginal hysterectomy*
 Vaginal delivery* (<5%
risk)
 IUD insertion/removal


cases of IE after dx GI/endoscopy
Durack, et al. NEJM 1995
Other Procedures




PROPHYLAXIS
Tonsillectomy
Rigid Bronchoscopy
Surgery involving resp
mucosa






*Optional for High risk pt
NO PROPHYLAXIS
Endotracheal intubation
Flex Bronchoscopy w/wo
biopsy*
Cardiac cath/stent
Pacer/ICD implantation
Incision/Bx of surgically
scrubbed skin
?Evidence linking IE to procedures
Largely circumstantial, unproven but based on
organisms involved and temporal relation to
procedures
 Animal studies 1970’s showed endocarditis
preventable with prophylaxis in rabbits
 Estimates show only ~ 6% of endocarditis cases
preventable with prophylaxis (240-480 cases
annually in US) but extensive morbidity/mortality
associated should sway toward appropriate
identification and prophylaxis of at risk pt
undergoing procedures known to cause
significant bacteremia

Prophylaxis
No randomized trials (would req 6000 pt
with cardiac dz, ?ethical)
 Retrospective analysis of 533 pt with
prosthetic valves undergoing dental/
surgical procedures

– No prophylaxis – 6/229 pt endocarditis
– Prophylaxis – 0/304
Horstkotte, et al. Eur Heart J 1987
Prophylactic Regimens
Dental/Oral, Respiratory, Esophageal
Situation
Agent
Regimen
Standard
Amoxicillin
2.0g 1hr prior
Standard, IV
Ampicillin
2.0g 30min prior
PCN Allergy
Clindamycin
Cephalexin
Azithro/Clarith
600mg
2.0g
500mg 1hr prior
PCN Allergy, IV
Clindamycin
Cefazolin
600mg
1.0g 30min prior
Prophylactic Regimens
GU/GI (excluding esophageal)
Situation
Agent
Regimen
High Risk
Ampicillin + Gent
Amp 2g Gent 1.5mg/kg (120max)
w/in 30 min of procedure
6hr later Amp 1g IV or Amox 1g po
High Risk
PCN Allergic
Vanc + Gent
Vanc 1g over 1-2hr + Gent 1.5
mg/kg complete infusion w/in 30min
Mod Risk
Amoxicillin or
Ampicillin
Amox 2g po 1hr before or
Amp 2g IV/IM within 30 min
Mod Risk
PCN Allergic
Vanc
Vanc 1g over 1-2 hr complete
infusion w/in 30 min of procedure
Dajani, et al. Circ 1997
Theoretical/Other Concerns with
“over prophylaxis”
Microbial Resistance
 Incidence of anaphylaxis (IV preps) may
override benefit when looking at overall
population if given in nonselective fashion

Our Patient - ? Missed opportunity
“low risk” procedure (colonoscopy/bx)
and organism common to oral mucosa
 BUT, significant association of sxs with
24-48hrs after colonoscopy/bx
 current guidelines would prophylax “hi
risk pt” but AI/AS not included in this
group

Conclusions
Recognize at risk patients in your care
 Educate them on importance of
prophylaxis (you may not get consulted
prior to procedures and not everyone
knows the risks – pt may have to act as
his own advocate )
 Err on the side of caution
