Infective endocarditis: Updated guidelines

Question 1

What were the four primary reasons for revising the AHA guidelines?

Answer 1

1. IE is much more likely to result from frequent exposure to random bacteremias associated with daily activities than from bacteremia caused by a dental, gastrointestinal (GI) tract or genitourinary (GU) tract procedure.
2. Prophylaxis prevents an exceedingly small number of cases of IE, if any, in individuals who undergo a dental, GI tract or GU tract procedure.
3. The risk of antibiotic-associated adverse events exceeds the benefit, if any, from prophylactic antibiotic therapy except in very high-risk situations.
4. Maintenance of optimal oral health and hygiene may reduce the incidence of bacteremia from daily activities and thus the risk of IE, and is more important than the use of prophylactic antibiotics for dental procedures.

Question 2

What is the risk of mortality from IE due to viridans streptococcal disease?

Answer 2

20% prosthetic valves

<5% native vales

Question 3

What are indications for prophylaxis against infective endocarditis in patients undergoing dental procedures?

Answer 3

1. Prosthetic cardiac valve or prosthetic material used for valve repair
2. Previous IE
3. Congenital heart disease (CHD)
   a) Unrepaired cyanotic CHD, including palliative shunts and conduits

b) Completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first six months after the procedure
c) Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device (which inhibit endothelialization)
4. Cardiac transplant recipients who develop cardiac valvulopathy
5. Rheumatic heart disease if prosthetic valves or prosthetic material used in valve repair

Question 4

When is prophylaxis not indictated?

Answer 4

1. ASD
2. VSD
3. PDA
4. Mitral valve prolapse
5. Previous Kawasaki disease
6. Hypertrophic cardiomyopathy
7. Previous coronary artery bypass graft surgery
8. Cardiac pacemakers (intravascular and epicardial) and implanted defibrillators
9. Bicuspid aortic valves
10. Coarctation of the aorta
11. Calcified aortic stenosis
12. Pulmonic stenosis

Question 5

Which procedures is it reasonable to give prophylaxis for?

Answer 5

1. All dental procedures that involve the manipulation of gingival tissue, the periapical region of teeth or the perforation of the oral mucosa
2. All invasive procedures of the respiratory tract that involves incision or biopsy of the respiratory mucosa

Question 6

Which procedures or events do not require prophylaxis?

Answer 6

1. Dental: Routine anesthetic injections through noninfected tissue, taking dental radiographs, placement of removable prosthodontic or orthodontic appliances, adjustment of orthodontic appliances, placement of orthodontic brackets, shedding of deciduous teeth, and bleeding from trauma to the lips or oral mucosa.
2. All GI or GU procedures
3. Bronchoscopy unless involves incision of the respiratory tract mucosa

Question 7

Which procedures in infected high-risk patients require treatment?

Answer 7

1. Established GI or GU infection include an agent active against enterococci
2. Skin, soft tissue, or MSK infections cover for staphylococci and GAS

Question 8

What is the antibiotic regimen recommended for prophylaxis?

Answer 8

Take single dose 30-60min prior to procedure of:
Amoxicillin 50mg/kg (max 2g) PO

If unable to take oral medication: Ampicillin 50mg/kg (max 2g) IV/IM OR
Cefazolin or ceftriaxone 50mg/kg (max 1g) IV/IM

If allergic to penicillin or ampicillin: Cephalexin 50mg/kg (2g max) PO
OR Clindamycin 20mg/kg (600mg max) PO
OR Azithromycin or clarithromycin 15mg/kg (500mg max) PO

If allergic to pencillin or ampicillin and unable to take oral medication: Cefazolin or ceftriaxone 50mg/kg (1g max) IV/IM OR
Clindamycin 20mg/kg (600mg max) IV/IM