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 Risk

1      Prosthetic Valves (400x risk 2 ) Previous endocarditis Congenital – 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 1 Durack, et al. NEJM 1995 2 Steckleberg, et al. Inf Dis Clin N Amer 1993 Mod Risk per 1997 AHA guidelines

Cardiac Conditions - Moderate Risk

1    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 teeth 1  Serratia marcesens introduced as sentinal organism shown to be present in venous blood immediately after tooth extraction 2  incidental bacteremia also seen in control groups, less often, less virulent 1 Okell, et al. Lancet. 1935 2 Burket, et al. J Dent Res 1937

Procedure related bacteremia

1     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 1 Durack, et al. NEJM 1995

Procedures

 Highest risk oral/dental  Int risk GU/Pulm  Low risk GI 1 Durack, 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         

NO PROPHYLAXIS

TEE* Endoscopy w/wo bx* 1 Ureteral catheterization D&C “Therapeutic” Ab Vaginal hysterectomy* Vaginal delivery* (<5% risk) IUD insertion/removal *Optional for High Risk pt 1 <10 cases of IE after dx GI/endoscopy Durack, et al. NEJM 1995

Other Procedures

   

PROPHYLAXIS

Tonsillectomy Rigid Bronchoscopy Surgery involving resp mucosa      

NO PROPHYLAXIS

Endotracheal intubation Flex Bronchoscopy w/wo biopsy* Cardiac cath/stent Pacer/ICD implantation Incision/Bx of surgically scrubbed skin *Optional for High risk pt

?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 Standard, IV PCN Allergy PCN Allergy, IV Dajani, et al. Circ 1997 Amoxicillin Ampicillin Clindamycin Cephalexin Azithro/Clarith Clindamycin Cefazolin 2.0g 1hr prior 2.0g 30min prior 600mg 2.0g

500mg 1hr prior 600mg 1.0g 30min prior

Prophylactic Regimens GU/GI (excluding esophageal)

Situation High Risk High Risk PCN Allergic Mod Risk Mod Risk PCN Allergic Dajani, et al. Circ 1997 Agent Ampicillin + Gent Vanc + Gent Regimen Amp 2g Gent 1.5mg/kg (120max) w/in 30 min of procedure 6hr later Amp 1g IV or Amox 1g po Vanc 1g over 1-2hr + Gent 1.5 mg/kg complete infusion w/in 30min Amoxicillin or Ampicillin Amox 2g po 1hr before or Amp 2g IV/IM within 30 min Vanc Vanc 1g over 1-2 hr complete infusion w/in 30 min of procedure

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