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Infective Endocarditis. Senior Oral Medicine Chapter 2 August 27, 2009 Susan Settle, D.D.S. Infective Endocarditis. A microbial infection of the endothelial surface of the heart or valves Usually is near congenital or acquired cardiac defects Designated by the causative organism
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Infective Endocarditis Senior Oral Medicine Chapter 2 August 27, 2009 Susan Settle, D.D.S.
Infective Endocarditis • A microbial infection of the endothelial surface of the heart or valves • Usually is near congenital or acquired cardiac defects • Designated by the causative organism • Also classified as NVE or PVE
Etiology • Usually Bacterial • Staphylococcus aureus Endocarditis • Streptococcus viridans Endocarditis • Actinobacillus actinomycetemcomitans Endocarditis • Sometimes Fungal • Candida albicans Endocarditis
Etiology • Streptococci most common cause (35-60%) • Mostly viridans group • Staphylococci about 30-40 and gaining • S. aureus most common cause in IVDU’s • Incidence increasing in hospital-acquired infections
Epidemiology • Incidence <1% Of General Population
Epidemiology • Population Groups At Greater Risk: • Rheumatic Fever History • Hemodialysis • Previous History Of Endocarditis • Patients With Prosthetic Valves • IV Drug Users (30% Risk Within 2 Years)
Predisposing Conditions • Mitral valve prolapse • Aortic valve disease • Congenital heart disease • Prosthetic valve • Intravenous drug use • No identifiable cause in 25-47%
Epidemiology • More Common In Men • Median Age 50 Years • Acute Cases Increasing • Streptococcal Cases Slightly; Fungal And Gram Negative Cases Increasing
Epidemiology • Incidence Increases With Age, Probably Due To Increased Cardiac Disease And Decreased Immunity • Prosthetic Heart Valve Infections Are Increasing
Dentistry And Endocarditis • Streptococcusviridans: Usual Etiologic Agent • Usually Is Not Acute (Subacute) • (That Is Why It Is Referred To As “SBE”) • Incubation Period Approximately Two Weeks
Epidemiology • Mitral Valve Prolapse: Only 1/4 Of MVP Patients Have Mitral Insufficiency (Regurgitation Or Murmur) - This Results In The Very Slight Increased Risk For Endocarditis
MVP • Mitral valve prolapse accounts for 25-30% of adult cases of native valve endocarditis • MVP is now the most common underlying condition among patients who develop infective endocarditis
Aortic Valve Disease Accounts for 12-30% of IE cases
Epidemiology • Fenfluramine (Pondimin) And Dexfenfluramine (Redux) Were Reported To Cause Cardiac Valvular Damage When Used For 4 Or More Months • Premedication No Longer Indicated
Epidemiology • Vena Cava Filters Or Umbrella Stents Placed To Catch Blood Clots Have Not Demonstrated Increased Risks
3 Types Of Endocarditis Lesions • Cardiac Lesions • Embolic Lesions: Friable Cardiac Lesions That Break Away • General Lesions
Cardiac Lesions • Usually Valvular • Most Often Mitral Valve • May Cover The Entire Valve • Mass Of Platelets, Fibrin And Bacteria • Sterile Vegetations May Occur In 50% Of Lupus Patients
Embolic Lesions • Osler’s Nodes: Are Small, Painful Petechiae In Extremities
Janeway Lesions • Pathognomonic of IE • Non-tender dermal abscesses
Splinter Hemorrhages Late-appearing symptom in endocarditis These represent damage to capillaries May also appear due to nail trauma
General Lesions • Enlarged Spleen • Arthritis • Clubbing Of Fingers • Cardiac Failure • Conduction Abnormalities • Stroke • Psychiatric Disease • Renal Failure
Mortality • Overall Rate About 40% • Death Usually Due To Heart Failure Resulting From Valve Dysfunction • Highest Death Rate Is In Early Prosthetic Valve Endocarditis
Classic Triad - But May Not Always Be Present 1. Fever 2. Positive Blood Culture 3. Heart Murmur • Sometimes Insidious Onset • “Flu-Like” Symptoms
Lab Findings • +Culture In 95% Of BE • Strep viridans Most Commonly Causes SBE • Staph aureus Most Commonly Causes ABE • Electrocardiography: Will Determine If Infection Progresses To Myocardium
Lab Findings • Echocardiography - As Important As A Positive Blood Culture Are Results Which Show Vegetations, Abscesses, Etc.
Major Diagnostic Criteria • Positive Blood Culture • Echocardiogram Findings Of Endocardial Involvement • New ValvularRegurgitation
Minor Diagnostic Criteria • Predisposing Heart Conditions • IV Drug Use • Vascular Emboli • Osler Nodes • Aneurysm • Roth Spots Of The Eye • Splinter Hemorrhages
Treatment • Treat It Early! • Culture • Use Bactericidal Agents • PCN G; Cefatriaxone; PCN G + Gentamicin; Nafcillin; Vancomycin
Treatment • Use Adequate Dosage • Parenteral Route • Sufficient Duration: 4-6 Weeks Or Longer
Dental Management • Prevention In Susceptible Patients: An Academic Issue • Very Few Cases Related In Time To Dental/Medical Procedures • Incidence Has Been Estimated To Be 100-200 Patients Susceptible To BE In A Dental Practice With 2,000 Patients
Antibiotic Prophylaxis • Regimen Designed For Alpha-hemolytic Strep (S. viridans) • No Clinical Trials Available To Show This Works! (Actually Prevents BE In Humans) • 25-50% Hospital Antibiotic Usage Is For Prophylaxis
Antibiotic Prophylaxis • Complications: Resistant Bacteria, Toxicity, Allergies, Suprainfections, Costs • Will Not Prevent All Cases
Antibiotic Prophylaxis • Allergy Morbidity Is Higher Than Endocarditis (Allergy To Premed) • 400-800 PCN Deaths Per Year • Effective For Patients With Prosthetic Valves And Previous Endocarditis History
American Heart Association Guidelines • Not Intended To Be A Standard Of Care • Not A Substitute For Clinical Judgment • Must Be Considered If You Receive A Medical Opinion That Conflicts With The Guidelines (You Are Responsible For The Outcome Of Your Patient’s Dental Treatment)
American Heart Association Guidelines • First Recommendations Were In 1955 • Can Still Develop Endocarditis Even When Using Guidelines
Prophylaxis Myths • Most Cases Of BE Of Oral Origin Are Caused By Dental Procedures • AHA Regimens Give Almost Total Protection Against Endocarditis After Dental Procedures
Prophylaxis Myths • If A Patient Is Taking Antibiotics For An Infection Before The Dental Procedure, You Do Not Need To Change The Patient To Another Antibiotic Before The Dental Procedure
Prophylaxis Myths • The Risk Of Endocarditis Is Greater Than The Risk Of Toxic Effects Of The Antibiotic
2007 AHA RecommendationsProphylaxis Indicated For The Following Groups Of Patients: • Those with a previous history of endocarditis • Those with prosthetic cardiac valves • Post-heart transplant patients with valvulopathy • Those with certain congenital types of heart disease
Congenital Heart DiseaseIndications for Prophylaxis • Unrepaired cyanotic CHD, including those patients with palliative shunts & conduits • Completely repaired CHD with prosthetic material or device placed by surgery or catheter during the first 6 months after the procedure • Repaired CHD with residual defects at the site or adjacent to the site of a prosthetic patch or prosthetic device, which inhibits endothelialization
Dental Procedures For Which Prophylaxis Is Recommended • All procedures involving manipulation of gingival tissue or the periapical region of teeth or perforation of oral mucosa • Excluded procedures: • Routine anesthetic injections through noninfected tissue • Radiographs • Placement of removable prosthodontic or orthodontic appliances • Adjustment of orthodontic appliances • Shedding of primary teeth and bleeding from trauma to lips or oral mucosa
Nonvalvular Cardiovascular Devices • Such as coronary artery stents, hemodialysis grafts • Routine antibiotic prophylaxis for dental procedures is not recommended • However, prophylaxis is recommended if an abscess is going to be incised & drained, • Or, if there is leakage present after the device is placed
Not In This Presentation! • Know Antibiotics in AHA Regimen • Know Dosages of These Antibiotics • Know The Regimen • Remember To Wait 9-14 Days Between Premed Appointments To Avoid Antibiotic Resistance Development • If Patient Is On A “Regimen” Antibiotic Switch To Another Drug In The Regimen