Major changes have been recently adopted by The American Heart
Association pertaining to antibiotic prophylaxis for the prevention of bacterial
endocarditis. The purpose of this news- letter is to provide you with a concise synopsis
of these changes Major changes in the updated recommendations include the following:
1. The recommendation emphasizes that most cases of endocarditis do not stem from
invasive procedures.
2. Risk categories are established for varying cardiac conditions as high, moderate,
and negligible risk for the potential outcome if endocarditis develops.
3. Procedures which can cause bacteremias and for which prophylaxis is recommended are
more clearly delineated.
4. Mitral valve prolapse has been set into an algorithm to define when such patients
are to be prophylaxed.
5. The initial dose of amoxicillin is reduced to 2 grams. The follow up dose is no
longer recommended for oral or dental procedures. Clindamycin and other alternatives are
to be used in penicillin sensitive patients. Additionally, the use of erythromycin has
been discontinued. [top]
Cardiac conditions associated with endocarditis. High risk category-
Prosthetic cardiac valves, including bioprosthetic and homograft valvesPrevious bacterial
endocarditis
Complex cyanotic congenital heart disease (single ventricle states, transposition of the
great arteries, tetralogy of Fallot)
Surgically constructed systemic pulmonary shunt. or conduits
Moderate risk category-
Most other congenital cardiac malformations (other than above and below)
Acquired valvular dysfunction (rheumatic heart disease)
Hypertrophic cardiomyopathy
Mitral valve prolapse with valvular regurgitation and/orthickened leaflets
Negligible risk category (no greater than the general population)-
Isolated secundum atrial septal defect
Surgical repair of atrial septal defect, ventricular septal defect or patent ductus
arteriosus (without residua beyond 6 mo.)
Previous coronary artery bypass graft surgery
Mitral valve prolapse without valvular regurgitation
Physiologic, functional or innocent heart murmurs
Previous Kawasaki disease without valvular dysfunction
Previous rheumatic fever without valvular dysfunction
Cardiac pacemakers (intravascular and epicardial)and implanted defibrillators [top]
Certainly also of great importance is knowing which dental procedures are most likely
to generate a bacteremia. The likelihood of a bacteremia to occur is directly related to
the amount of infection and inflammation in area to be operated and the degree of
invasiveness of each procedure. The August issue of the Journal of the American Dental
Association (vol 128:1147, 1997) has an excellent table of reference which is included at
the top of the next page.
ENDOCARDITIS PROPHYLAXIS RECOMMENDED
-Dental extractions
-Periodontal procedures including surgery, scaling and root planing, probing and recall
maintenance
-Dental implant placement and reimplantation of avulsed teeth
-Endodontic (root canal) instrumentation or surgery only beyond the apex
-Subgingival placement of antibiotic fibers or strips
-Initial placement of orthodontic bands but not brackets
-Intraligamentary local anesthetic injections
-Prophylactic cleaning of teeth or implants where bleeding is anticipated. [top]
ENDOCARDITIS PROPHYLAXIS NOT ADVISED
-Restorative dentistry (operative and prosthodontic) with or without retraction cord
-Local anesthetic injections (non- intraligamentary)
-Intracanal endodontic treatment; post placement and buildup
-Placement of rubber dams
-Postoperative suture removal
-Placement of removable prosthodontic or orthodontic appliances
-Taking of oral impressions
-Fluoride treatments
-Taking of oral radiographs
-Orthodontic appliance adjustment
-Shedding of primary teeth[top]
You must exercise sound clinical judgment if you anticipate that a procedure could
become invasive and create significant bleeding in a patient with high or moderate risk of
bacteremia. Also note: 15 ml (one tablespoon) of chlorhexidine administered for a 30
second rinse can decrease the incidence and magnitude of bacteremia.
Prophylaxis Regimen Summary Standard General
Prophylaxis-
Amoxicillin --Adults 2.0g; Children 50mg/kg orally, 1hr prior
Unable to take oral medications-
Ampicillin--Adults 2.0g IM or IV given within 30 min prior to appt. Children 50 mg/kg IM
or IV within 30 min prior to appt.
Allergic to Penicillins-
Clindamycin- Adults 600mg; Children 20mg/kg 1hr prior to appt. OR Cephalexin or
Cephadroxil (in patients without immediate penicillin hypersensitivity reactions) Adults
2.0 g; Children 50mg/kg 1hr prior to appt. Azithromycin or clarithromycin- Adults 500mg;
Children 15mg/kg 1 hr prior to appointment.
Allergic to Penicillin and unable to take oral medications -
Clindamycin- Adults 600mg; children 20mg/kg IV 30 within minutes prior to appt. Cephazolin
(in patients without immediate penicillin hypersensitivity reactions) Adults- 1.0g;
children- 25mg/kg IM or IV given within 30 min prior to appointment. [top]
Mitral Valve Prolapse-
The most important parameter to consider in MVP patients is whether or not there is mitral
regurgitation. Any patient with regurgitation must be prophylaxed. Many patients with a
history of mitral valve prolapse have no knowledge of whether regurgitation is present.
Consultation with the physician is important in these cases. Note- many authorities
advise, from medical legal viewpoint it is preferable that the physician prescribe the
antibiotic regimen best suited for the patient. This is especially true in cases of major
joint prostheses where only a small number of patients may be at a potentially increased
risk for hematogenous total joint infection. [top]
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