Prevention of endocarditis: Antibiotic prophylaxis and other measures

INTRODUCTION — Measures for prevention of infective endocarditis (IE) are discussed here, including the clinical approach and rationale for antibiotic prophylaxis prior to dental procedures.

The indications for IE prophylaxis in 2021 American Heart Association (AHA) guidelines are narrower than indications outlined in prior (AHA) guidelines. The approach of the 2023 European Society of Cardiology (ESC) guidelines is similar to that of the AHA guidelines. These guidelines take into consideration both patient-based and procedure-based risk factors for IE [1-3].

An overview of management of IE in adults is presented separately. (See "Overview of management of infective endocarditis in adults".)

OVERVIEW — Measures for prevention of IE include:

●Maintenance of oral hygiene. (See 'Maintenance of oral hygiene' below.)

●Antibiotic prophylaxis prior to invasive dental or invasive oral procedures. (See 'Antibiotic prophylaxis prior to invasive dental or oral procedures' below.)

●Timely treatment of infection with pathogens likely to cause endocarditis. (See 'Timely treatment of infection' below.)

●Antibiotic prophylaxis for surgical site infection reduces the risk of surgical site infection, as discussed separately, and has been postulated to reduce the risk of subsequent endocarditis. A key example of this approach is antibiotic prophylaxis prior to cardiac surgery. (See 'Antibiotic prophylaxis for surgical site infection' below.)

●Closure of a patent ductus arteriosus or ventricular septal defect. (See 'Closure of PDA or VSD' below.)

These are discussed further below.

DENTAL HEALTH

Maintenance of oral hygiene — Maintenance of oral hygiene is important to reduce the risk of gingivitis and periodontitis as well as the risk of bacteremia. All individuals at risk for developing IE should establish and maintain a program of oral health care including regular professional care, the regular use of manual or powered toothbrushes, dental floss, and other plaque-removing devices. (See "Overview of gingivitis and periodontitis in adults", section on 'Prevention of plaque-associated gingivitis and periodontitis'.)

Maintenance of oral hygiene plays a more important role in reducing the risk of IE than antibiotic prophylaxis; IE is more likely to occur as a result of bacteremia associated with daily activities (such as tooth brushing) than from bacteremia associated with invasive dental procedures.

Studies highlight the importance maintaining good oral hygiene for prevention of bacteremia and IE include:

●A trial including 194 patients undergoing tooth brushing in which the risk of bacteremia was highest among those with poor oral hygiene; patients with mean plaque and calculous indices ≥2 had a 3.78- and 4.43-fold increased risk of bacteremia, respectively [4].

●A case-control study including 181 patients with community-associated IE; the case patients (those with IE) had a 53 percent greater mean dental calculous index and 26 percent greater mean plaque index than controls [5].

Antibiotic prophylaxis prior to invasive dental or oral procedures

Clinical approach — Antibiotic prophylaxis is warranted for patients with cardiac conditions that confer the highest risk of adverse outcome from IE (see 'Which patients?' below), prior to invasive dental or invasive oral procedures (algorithm 1) [1,2] (see 'Which procedures?' below and 'On risk of endocarditis' below).

The above approach contrasts with the approach described in guidelines issued prior to 2007, which recommended prophylaxis for patients at moderate risk or high risk of IE (a much larger population) [6].

Which patients?

●Highest risk – Antibiotic prophylaxis is warranted for patients with conditions or implanted devices associated with the highest risk of an adverse outcome if IE occurs [1-3].

Conditions associated with highest risk of adverse outcomes from IE include [1,3]:

•Prosthetic cardiac valve or valve repair with prosthetic valve material.

-Prosthetic heart valve (surgical or transcatheter)

-Cardiac valve repair with prosthetic material (including annuloplasty rings or clips)

•Durable mechanical circulatory support device (ventricular assist device or artificial heart).

•Previous, relapsed, or recurrent IE.

•Certain types of congenital heart disease including:

-Unrepaired cyanotic congenital heart disease (patients with palliative shunts and conduits are still considered unrepaired).

-Completely repaired congenital heart defect with prosthetic material or device (eg, septal closure device), during the first six months after surgical or transcatheter placement.

-Repaired congenital heart disease with residual defect at the site or adjacent to the site of a prosthetic patch or prosthetic device.

-Prosthetic pulmonary artery valve or conduit (surgical or transcatheter; eg, Melody valve and Contegra conduit).

•Cardiac transplant recipients who develop cardiac valvulopathy.

•Left atrial appendage occlusion device, during the first six months after percutaneous or surgical placement [3].

●Intermediate risk – Patients at intermediate risk of adverse outcomes from IE include those with valve disease (acquired [rheumatic or non-rheumatic] or congenital), hypertrophic cardiomyopathy, or a cardiovascular implanted electronic device [3]. For patients with intermediate risk of adverse outcomes from IE, antibiotic prophylaxis is not routinely recommended, but other preventive measures apply. (See 'Overview' above.)

The ESC 2023 guidelines noted that in patients at intermediate risk of IE, antibiotic prophylaxis is not routinely recommended and may be considered on an individual basis. Given the available evidence, the author and section editors think that this is a reasonable approach [3].

●Supporting evidence – The above approach is supported by a Danish nationwide registry study including more than 25,000 at high risk for IE (due to prior IE, presence of a prosthetic heart valve, or presence of complex congenital heart disease) [7]. Complex congenital heart disease was identified (largely in infants and children) by a diagnosis code for tetralogy of Fallot, transposition of the great arteries, or truncus arteriosus and was not limited to unrepaired cyanotic heart disease. The cumulative risk of IE at 10 years of follow-up among these groups was 8.8, 6.0, and 1.3 percent, respectively.

On the other hand, there are data suggesting that classification of conditions in the high- versus low/moderate-risk groups should be considered carefully. In one cohort study including more than 3000 patients with IE, the rate of intracardiac complications was similar among those with bicuspid aortic valve and mitral valve prolapse (considered moderate risk) to those in the high-risk group (50 and 47 versus 30 percent; p<0.01) [8]. Another study among patients in the United Kingdom demonstrated that the risk of IE or death during hospitalization for IE associated with some conditions in the moderate-risk group (eg, a broad group of congenital valve anomalies) was similar to the risk associated with some conditions in the high-risk group (eg, prosthetic valves) [9]. These studies are limited in methodology and illustrate the complexities in categorizing patients as high versus low/moderate risk.

Which procedures?

Invasive dental or oral procedures — The risk of IE is highest for invasive dental or invasive oral procedures that involve manipulation of gingival tissue or the periapical region of the teeth or perforation of the oral mucosa, such as tooth extractions, drainage of a dental abscess, or dental implant procedure (algorithm 1) [2,3]. Among invasive dental procedures, the greatest risk may arise from dental extractions and other oral surgery; the risk from routine dental cleaning is less certain.

In contrast, the following dental procedures and events do not require prophylaxis: anesthetic injections through noninfected tissue, taking dental radiographs, placement or adjustment of removable prosthodontic or orthodontic appliances, placement of orthodontic brackets, shedding of primary teeth, and bleeding from trauma to lips or oral mucosa [2].

Other potential scenarios for prophylaxis — The indications for IE prophylaxis in the 2021 American Heart Association (AHA) guidelines are narrower than indications outlined in prior AHA guidelines [1,2].

Antibiotic prophylaxis is not recommended for procedures including transesophageal echocardiography, esophagogastroduodenoscopy, colonoscopy, or cystoscopy in the AHA guidelines [1,2]; in contrast, the 2023 European Society of Cardiology (ESC) guidelines state that antibiotic prophylaxis may be considered for high risk patients undergoing invasive diagnostic or therapeutic procedures of the respiratory, gastrointestinal, genitourinary, skin, or musculoskeletal system [3]. This guideline difference reflects the lack of evidence to support antibiotic prophylaxis for the aforementioned procedures and the divergence of expert opinion in this area. (See 'Other procedures' below.)

Other potential scenarios for IE prophylaxis include pregnancy and skin and soft tissue infection; these are discussed separately. (See "Pregnancy and valve disease" and "Skin abscesses in adults: Treatment".)

Which regimen?

Antibiotic selection

●General approach – Antibiotic prophylaxis regimens for invasive dental or invasive oral procedures target prevention of viridans group streptococcal IE. The preferred regimen is oral amoxicillin (adults: 2 grams; children: 50 mg/kg); alternative regimens are summarized in the table (table 1) [2].

Clindamycin is no longer recommended as an alternative antibiotic regimen for patients undergoing dental procedures, given more frequent and severe adverse reactions associated with this drug compared with other antibiotic agents [2]. In one study of adverse reactions to antibiotics used as endocarditis prophylaxis in England between 2004 and 2014, the rate of adverse drug reactions for amoxicillin was 0 fatal and 23 nonfatal reactions per million prescriptions; for clindamycin, the rate was 13 fatal and 149 nonfatal reactions per million prescriptions [10]. The majority of serious adverse drug reactions associated with clindamycin were due to Clostridioides difficile infection.

●Patients on concurrent antibiotic therapy

•Oral antibiotic therapy – If a patient is receiving oral antibiotic therapy for other indications at the time that an invasive dental or invasive oral procedure is undertaken, selection of an alternate antibiotic of a different class among the standard regimens is preferred (table 1) [2]. As an example, if a patient receiving penicillin for rheumatic fever prophylaxis undergoes an invasive dental procedure and requires IE prophylaxis, cephalexin or azithromycin may be chosen.

If a patient is receiving a short course (eg, 7 to 10 days) of oral antibiotic therapy prior to an elective invasive dental or invasive oral procedure for another indication, delaying the invasive dental or invasive oral procedure until ≥10 days after completion of the antibiotic treatment course is preferred, if possible [2].

•Parenteral antibiotic therapy – For patients receiving a parenteral antibiotic that is active against viridans group streptococcus at the time of an invasive dental or invasive oral procedure, the same parental antibiotic is continued through the dental procedure [2].

Timing — In general, antibiotics should be administered 30 to 60 minutes prior to the procedure (an exception is intravenous vancomycin, which should be administered 120 minutes prior to the procedure) [2]. The 2013 guidelines for preoperative antibiotic prophylaxis stipulate the optimal timing is within 60 minutes prior to surgery [11].

If antibiotic prophylaxis is inadvertently not administered prior to the dental procedure, it may be administered up to two hours after the procedure [2].

Adverse effects — Although antibiotic exposure is limited with antibiotic prophylaxis therapy, there is a risk of adverse effects. Use of antibiotic prophylaxis beyond the recommend clinical settings should be avoided given the risk of antibiotic-associated adverse events.

●Adverse reactions – Patients receiving antibiotic prophylaxis may experience adverse effects from antibiotics including allergic reactions, even when only a single dose of antibiotic is administered [2]. The antibiotic regimen chosen is tailored based upon the presence and type of prior allergic reaction to penicillin (table 1).

As discussed above, clindamycin is no longer used for antibiotic prophylaxis given the risk of adverse reactions associated with this drug. (See 'Antibiotic selection' above.)

●Development of resistance – Widespread antibiotic use contributes to the risk of increasingly resistant microorganisms, including viridans group streptococcus [2,12]. (See "Antimicrobial stewardship in outpatient settings".)

Rationale — The pathogenesis of IE is presumed to involve the following sequence of events [13]:

●Formation of a small thrombus on an abnormal endothelial surface

●Secondary infection of this nidus with bacteria that are transiently circulating in the bloodstream

●Proliferation of bacteria resulting in the formation of vegetations on the endothelial surface

Since the occurrence of bacteremia is crucial to the initiation of an episode of IE, it has been postulated that preventing or promptly treating transient bacteremia can prevent the above events. (See "Pathogenesis of vegetation formation in infective endocarditis".)

Summary of prophylaxis effects and limitations — Use of antibiotic prophylaxis for prevention of IE is based on observational data suggesting that invasive dental or invasive oral procedures may increase the risk of IE in patients at high risk for IE and that antibiotic prophylaxis may decrease this risk; however, benefit from antibiotic prophylaxis has not been definitively established.

The 2007 AHA guideline for the prevention of IE [14] included major revisions to the 1997 AHA guideline, the 2005 Medical Letter update of the 1997 AHA guidelines [15], and the 2006 American College of Cardiology (ACC)/AHA guideline on the management of valvular heart disease [6]. Subsequent ACC/AHA guidelines updates were published in 2014, 2017, and 2020 [1,16-18]. In 2021, the AHA published a statement analyzing the impact of the 2007 guidelines on the incidence and outcome of IE due to viridans group streptococci, with further recommendations on use of antibiotic prophylaxis [2]. The 2023 ESC guidelines are largely in agreement with the preceding American guidelines [3,19].

Assessing the utility of antibiotic prophylaxis is limited by the frequency of IE with no identifiable preceding procedure, the low rate of IE following invasive dental procedures without prophylaxis, and the potential for prophylaxis failure. Thus, it has been estimated that, even if antibiotic prophylaxis is fully effective, less than 10 percent of all cases of endocarditis could be prevented by use of antibiotic therapy prior to procedures [20]. In addition, observed rates of adherence to guidelines for antibiotic prophylaxis for patients at high risk for IE are low (ranging from 26 to 50 percent) [21]. (See 'On risk of endocarditis' below and 'Impact of procedures on risk of endocarditis' below.)

Various epidemiologic studies have suggested that up to 5 percent of all IE cases were preceded by an invasive dental procedure [22,23]. However, even in cases in which there is a close temporal relationship between a dental procedure and the occurrence of endocarditis, causality is uncertain, as it is possible that endocarditis occurred as a consequence of the dental condition that led to the procedure or from routine tooth brushing. (See 'Impact of procedures on risk of endocarditis' below.)

In a study from the United States, the risk for individuals with high IE risk of developing IE within 30 days after an invasive dental procedure was 3.58 per 10,000 individuals with antibiotic prophylaxis and 10.09 per 10,000 individuals with no antibiotic prophylaxis (odds ratio [OR] 0.38, 95% CI 0.22-0.62) [21] (see 'On risk of endocarditis' below). Thus, a large number of prophylaxis doses are necessary to prevent a very small number of IE cases.

Impact of procedures on risk of endocarditis

Invasive dental procedures — Invasive dental procedures may contribute to the risk of IE, although observational data suggest that most cases of IE do not occur after such procedures.

Some [21,23], but not all [24], case-crossover studies suggest that invasive dental procedures are associated with risk of IE. One case-crossover and cohort study among nearly 8 million individuals in the United States suggested that the risk associated with invasive dental procedures may be limited to specific procedures (eg, extractions and other oral surgery) [21]. In the case-crossover analysis, among individuals with high IE risk, a significant temporal association was observed between IE and invasive dental procedures in the preceding four weeks (OR 2.00, 95% CI 1.59-2.52). This relationship was strongest for dental extractions (OR 11.08, 95% CI 7.34-16.74) and oral surgical procedures (OR 50.77, 95% CI 20.79-123.98).

The impact of invasive dental procedures on the risk of IE in patients with prosthetic valves was assessed by a French population-based cohort and case-crossover study [23]. In the cohort study, there was no significant difference in the risk of oral streptococcal IE in the three-month period after an invasive dental procedure (risk ratio [RR] 1.25, 95% CI 0.82-1.82) or after an invasive dental procedure without antibiotic prophylaxis (RR 1.57, 95% CI 0.90-2.53) compared with nonexposure periods. However, in the case-control analysis, invasive dental procedures were more frequent during case periods, defined as the three months preceding oral streptococcal IE, than during control periods, defined as months 9 to 7 before, months 15 to 13 before, and months 21 to 19 before in the same participants (5.1 versus 3.2 percent; OR 1.66, 95% CI 1.05-2.63).

In contrast, a similar population-based case-crossover and self-controlled case series study performed in Taiwan found no association between invasive dental treatment and subsequent risk for IE in patients with high IE risk [24].

Other procedures — The impact of nondental procedures on the risk of IE has been assessed in population-based case-crossover studies:

●In a Swedish study, several invasive procedures (including coronary artery bypass grafting, procedures of the skin and management of wounds, transfusion, dialysis, bone marrow puncture, and some endoscopies including bronchoscopy) were strongly associated with an increased risk of IE in the 12-week interval following the procedure [25]. However, the clinical significance is uncertain, since information on prior antibiotic use and the microbiology of IE were not provided. In addition, the role of confounders related to general risk of IE in hospitalized patients and patients with significant underlying health comorbidities was not examined.

●In a study using a large administrative database in the United Kingdom, there was a temporal association between procedures such as permanent pacemaker and defibrillator implantation, surgical tooth extraction, upper and lower gastrointestinal endoscopy, and bone marrow biopsy and IE [26]. The association cannot be interpreted as causal because of important confounders and lack of microbiologic data; however, these findings warrant further study.

Effect of antibiotic prophylaxis — Antibiotic trials have examined the impact of antibiotic prophylaxis on bacteremia, but only observational data are available on the effect of antibiotic prophylaxis on the risk of IE.

On bacteremia — All prospective antibiotic prophylaxis trials (21 included in a meta-analysis) used bacteremia as an endpoint rather than IE [27]. The meta-analysis found that antibiotic prophylaxis was effective in reducing the incidence of bacteremia (RR 0.53, 95% CI 0.49-0.57).

On risk of endocarditis — Observational data suggest that antibiotic prophylaxis may reduce the risk of IE following invasive dental procedures in patients with high IE risk.

The above cited case-crossover analysis among nearly 8 million individuals in the United States identified a benefit from antibiotic prophylaxis prior to invasive dental procedures [21]. In individuals at high IE risk, antibiotic prophylaxis before invasive dental procedures was associated with reduction in the risk of developing IE within 30 days (OR 0.49, 95% CI 0.29-0.85). This reduction in risk with antibiotic prophylaxis was most marked following extractions (OR 0.15, 95% CI 0.04-0.55), and there was a nonsignificant trend toward reduction with other oral surgical procedures (adjusted OR 0.08, 95% CI 0.01-1.13).

Prior studies failed to show an impact from antibiotic prophylaxis on IE rates, but may have been underpowered [23,27].

Even if antibiotic prophylaxis reduces risk of IE, it may fail. One report included 52 cases of IE that occurred despite receipt of antibiotic therapy prior to invasive procedures [28]. In the 43 cases with antibiotic susceptibility data, 63 percent of the pathogens were susceptible to the prophylactic antibiotic agents that were administered. However, only six cases (12 percent) received regimens recommended by the AHA.

Effect of guideline changes — Increases in IE incidence observed in some studies have raised concern that reduced IE prophylaxis in response to guideline changes may have contributed to increased IE rates [29-32]. However, a causal connection is uncertain given the absence of controlled data. Factors that may contribute to perceived increasing rates of IE include lower thresholds for diagnosis of IE, increased prevalence of risk factors, increases in procedures predisposing to IE, and inaccurate coding or counting [31].

The above cited systematic review included 10 time-trend studies examining the effect of antibiotic prophylaxis guideline change on the incidence of IE, including nine studies of relative antibiotic prophylaxis restriction and one study examining the effect of total antibiotic prophylaxis restriction [27]:

●Among the studies of the effect of relative antibiotic prophylaxis restriction (from the United States and Europe), the reported incidence of IE is increasing; however, a significant inflection point (alteration in the rate of change) in the incidence trend of IE was not identified. Even larger studies may be underpowered to detect a significant change in IE incidence, given limited duration of follow-up.

●Conflicting results have been reported regarding the incidence of streptococcal IE, with some studies reporting a significant increase in the incidence of streptococcal IE [33] and other studies finding no increase in incidence of viridans group streptococcal IE [34,35]. One study reported a decrease in the incidence of streptococcal IE [36].

The National Institute for Health and Care Excellence (NICE) issued 2008 guidelines recommending complete cessation of antibiotic prophylaxis for IE prevention [37]. In a subsequent study examining the effect of this intervention, a significant increase in the incidence of IE was observed by March 2013 in England; 35 more cases of IE per month were reported than expected based upon the historical trend [31]. In contrast, an analysis of IE incidence in Scotland demonstrated no change in incidence of IE after the 2008 guideline change [38]. The NICE guidelines were revised in 2016 to include the word "routinely" in the following statement: "Antibiotic prophylaxis against infective endocarditis is not recommended routinely for people undergoing dental procedures" [39].

Similarly, complete cessation of antibiotic prophylaxis was recommended in Sweden in October 2012. An analysis of IE incidence in Sweden before and after the recommendation showed no statistically significant increase in the trend line of IE caused by viridans group streptococci [40].

Subsequent studies compared rates of antibiotic prophylaxis and incidence of endocarditis relative to time before or after publication of the 2007 AHA guidelines [32,41]:

●The first study evaluated patients in the United States before (2003 to 2007) and after (2008 to 2015) publication of the 2007 AHA guidelines [32]. Among moderate-risk individuals, there was a 64 percent (95% CI 59-68 percent) reduction in the rate of antibiotic prescribing, and a 75 percent increase in IE incidence (75%, 95% CI 3-200 percent). Among high-risk individuals, there was a 20 percent reduction in the rate of antibiotic prescribing (95% CI 4-32 percent), and an increase in IE incidence (177 percent; 95% CI 66-361 percent).

●The second study evaluated data on patients in Ontario, Canada between 2002 and 2014 [41]:

•Prescription information was reported for adults ≥65 years of age. In the moderate-risk group, there was a decline in antibiotic prophylaxis prescriptions after the guideline revision (mean quarterly prescriptions 30,680 versus 17,954 per 1 million population); in the high-risk group, there was a slight decrease followed by a gradual increase in prophylaxis prescriptions.

•Among adults ≥65 years old, there was an increase in IE-related hospitalizations (with a higher magnitude in the high-risk versus moderate-risk group) starting three years after the AHA guideline revision. A similar pattern of IE-related hospitalizations was observed among adults 18 to 64 years of age in high- or moderate-risk groups. Among adults ≥65 years of age, there was no significant change in the proportion of Staphylococcus aureus and streptococcal IE episodes over time; among adults 18 to 64 years of age, there was a reduction in the proportion of streptococcal IE and an increase in proportion of S. aureus IE.

These studies identify a decrease in antibiotic prophylaxis and an increase in IE incidence after publication of the 2007 antibiotic guideline but do not establish causality, particularly given the three-year gap between guideline publication and increase in IE incidence in the latter study. The decrease in proportion of streptococcal IE despite antibiotic prophylaxis restriction in adults 18 to 64 years of age suggests lack of a causal relationship although this finding is difficult to interpret given the presence of other factors including increasing prevalence of history of drug abuse in this group.

ADDITIONAL PREVENTIVE MEASURES

Timely treatment of infection — While timely treatment of infection is a cornerstone of medical care, effective treatment may be delayed by myriad causes including gaps in patient education and access to care, atypical clinical presentation, systems failures (eg, incomplete reporting of laboratory results), misdiagnosis, antimicrobial resistant pathogens, and delay in removing infected implanted devices or material (eg, catheters).

A corollary to antimicrobial treatment of infections is the practice of ensuring appropriate antimicrobial coverage for potential endocarditis pathogens in infected organs or tissues prior to performing invasive procedures on these infected sites, although evidence is lacking to support this approach.

There are no data to suggest that the use of antibiotics to eradicate bacteria with potential to cause IE from the urinary tract prior to genitourinary procedures reduces the risk of IE. The use of antibiotic prophylaxis prior to urinary interventions is discussed separately. (See "Asymptomatic bacteriuria in adults", section on 'Patients undergoing urologic intervention'.).

Antibiotic prophylaxis for surgical site infection — Antibiotic prophylaxis is warranted for patients undergoing certain invasive procedures to reduce the risk of surgical site infection. A key example is implantation of prosthetic heart valves (surgical or transcatheter), prosthetic intravascular material, or prosthetic intracardiac material (table 2); this intervention is beneficial for prevention of surgical site infection and might reduce the risk of early prosthetic valve endocarditis, although evidence is limited [42].

The recommended antimicrobial is based upon the specific type of invasive procedure (eg, cardiac versus gastrointestinal surgery) and does not differ for patients with high risk of adverse outcomes from IE. This approach is discussed further separately. (See "Antimicrobial prophylaxis for prevention of surgical site infection in adults" and "Antimicrobial prophylaxis for prevention of surgical site infection in adults", section on 'Cardiac surgery' and "Transcatheter aortic valve implantation: Periprocedural and postprocedural management", section on 'Procedural antibiotic prophylaxis'.)

Closure of PDA or VSD — For patients with history of IE and patent ductus arteriosus (PDA) without severe pulmonary hypertension closure is warranted to reduce endocardial injury related to the high-velocity shunt, which may be a nidus for IE. (See "Management of patent ductus arteriosus (PDA) in term infants, children, and adults", section on 'Indications for closure'.)

For patients with history of IE and ventricular septal defect (VSD) without contraindications to VSD closure, an individualized assessment of the risks and benefits of VSD closure is performed. (See "Management and prognosis of congenital ventricular septal defect in adults", section on 'VSD closure'.)

Patients with history of IE with successfully closed PDA or VSD should continue to receive antibiotic prophylaxis prior to dental procedures.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Treatment and prevention of infective endocarditis".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topic (see "Patient education: Endocarditis (The Basics)")

●Beyond the Basics topic (see "Patient education: Antibiotics to prevent heart valve infections (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Preventive measures – Preventive measures to reduce the risk of infective endocarditis (IE) include:

•Maintenance of oral hygiene. (See 'Maintenance of oral hygiene' above.)

•Timely treatment of infection with pathogens that cause endocarditis. (See 'Timely treatment of infection' above.)

•Antibiotic prophylaxis prior to invasive dental or invasive oral procedures. (See 'Antibiotic prophylaxis prior to invasive dental or oral procedures' above.)

•Antibiotic prophylaxis for surgical site infection reduces the risk of surgical site infection, as discussed separately, which may reduce the risk of subsequent endocarditis. A key example of this approach is antibiotic prophylaxis prior to cardiac surgery. (See 'Antibiotic prophylaxis for surgical site infection' above.)

•Closure of a patent ductus arteriosus (PDA) or ventricular septal defect (VSD). (See 'Closure of PDA or VSD' above.)

●Antibiotic prophylaxis prior to dental procedures − For patients with cardiac conditions which confer the highest risk of adverse outcome from IE who are undergoing invasive dental or invasive oral procedures, we recommend administering antibiotic prophylaxis (algorithm 1) (Grade 1B). (See 'Clinical approach' above and 'Which patients?' above and 'Which procedures?' above.)

●Which patients? – Antibiotic prophylaxis prior to invasive dental or invasive oral procedures is warranted only for patients with conditions or implanted devices associated with the highest risk of an adverse outcome if IE occurs. These include (see 'Which patients?' above):

•Prosthetic cardiac valve or valve repair with prosthetic valve material, including:

-Prosthetic heart valve (surgical or transcatheter)

-Cardiac valve repair with prosthetic material (including annuloplasty rings or clips)

•Implanted durable mechanical circulatory support device (ventricular assist device or artificial heart).

•Previous, relapsed, or recurrent IE.

•Certain types of congenital heart disease including:

-Unrepaired cyanotic congenital heart disease, including palliative shunts and conduits.

-Completely repaired congenital heart defect with prosthetic material or device, during the first six months after surgical or transcatheter placement.

-Repaired congenital heart disease with residual defect at the site or adjacent to the site of a prosthetic patch or prosthetic device.

-Prosthetic pulmonary artery valve or conduit (surgical or transcatheter; eg, Melody valve and Contegra conduit).

•Cardiac transplant recipients who develop cardiac valvulopathy.

•Left atrial appendage occlusion device, during the first six months after percutaneous or surgical placement [3].

●Which procedures? − The risk of IE is highest for invasive dental or invasive oral procedures that involve manipulation of gingival tissue or the periapical region of the teeth or perforation of the oral mucosa, such as tooth extractions or drainage of a dental abscess (algorithm 1). Among invasive dental procedures, the greatest risk may arise from dental extractions and other oral surgery; the risk from routine dental cleaning is less certain. (See 'Which procedures?' above.)

●Which regimen? – Antibiotic prophylaxis regimens for invasive dental or invasive oral procedures target prevention of viridans group streptococcal IE. The preferred regimen is oral amoxicillin; alternative regimens are summarized in the table (table 1). (See 'Antibiotic selection' above.)

ACKNOWLEDGMENT — The UpToDate editorial staff acknowledges Daniel J Sexton, MD, who contributed to earlier versions of this topic review.