INFECTIVE ENDOCARDITIS IN PREGNANCY

Introduction

Infective endocarditis (IE) during pregnancy is a rare but life-threatening condition that can lead to severe maternal and fetal complications if not promptly diagnosed and treated. The increased cardiovascular demands of pregnancy, combined with the immunological adaptations required to tolerate the fetus, may predispose pregnant women to infections, particularly those with pre-existing cardiac conditions. Despite its low incidence (estimated at less than 0.01%), IE is associated with maternal mortality rates as high as 22% and fetal mortality rates up to 15% in cases of delayed or inadequate management​.

Epidemiology

Infective endocarditis (IE) during pregnancy is extremely rare, with an estimated incidence of less than 0.01% of all pregnancies​. Despite its rarity, IE is associated with high maternal and fetal mortality rates, particularly in the absence of timely diagnosis and intervention. The maternal mortality rate ranges between 22% and 33%, while fetal mortality rates vary from 14% to 29%, with a significant portion of fetal deaths resulting from preterm delivery and intrauterine growth restriction​. These poor outcomes are often linked to the severity of the underlying cardiac condition and the hemodynamic stress imposed by pregnancy​.

Pathophysiology

The pathophysiology of infective endocarditis (IE) in pregnancy is shaped by the unique physiological and immunological adaptations that occur during gestation. Several key changes in cardiovascular dynamics and immune function increase the susceptibility of pregnant women to endocardial infections, particularly in those with underlying cardiac conditions such as congenital heart disease, prosthetic valves, or rheumatic heart disease​

Hemodynamic Changes in Pregnancy

Pregnancy induces profound changes in the cardiovascular system to accommodate the increased metabolic demands of the growing fetus. These changes include:

  • Increased cardiac output: Cardiac output increases by 30% to 50% during pregnancy, peaking in the second trimester. This results from both increased stroke volume and a higher heart rate​​. In women with pre-existing valve abnormalities or prosthetic valves, this increased flow can exacerbate turbulent blood flow across damaged or artificial valves, promoting endothelial injury, a key step in the development of vegetations​. 
  • Vascular resistance and blood volume: There is a concurrent decrease in systemic vascular resistance, which reduces afterload. Blood volume also increases by approximately 50%, creating a hyperdynamic circulatory state that can stress the cardiovascular system​. In those with structural heart disease, this combination of increased volume and decreased resistance can predispose to valve damage and vegetation formation​..
  • Hypercoagulable state: Pregnancy is a prothrombotic state, characterized by increased levels of clotting factors and decreased fibrinolytic activity​. This hypercoagulability enhances the risk of thrombus formation on heart valves, which can act as a nidus for bacterial colonization during transient bacteremia, leading to the development of IE

Immune System Modulation in Pregnancy

The maternal immune system undergoes significant alterations during pregnancy to tolerate the semi-allogenic fetus. While these changes protect the fetus from maternal immune attack, they also render the mother more susceptible to infections:

  • Immune suppression: There is a reduction in adaptive immunity, particularly in T-cell mediated responses, to avoid fetal rejection​. This immune suppression can hinder the mother’s ability to mount an effective response to infections, including bacteremia, increasing the likelihood of bacterial adherence to the endocardium​.
  • Shift towards innate immunity: While adaptive immunity is suppressed, innate immunity remains active, with increased levels of pro-inflammatory cytokines and phagocytic activity. However, this shift is insufficient to prevent infections such as IE, particularly when bacteria such as Staphylococcus aureus or Streptococcus viridans are involved​.

Vegetation Formation and Bacteremia

The formation of vegetations is central to the development of IE. The process begins with endothelial injury, which can result from turbulent blood flow across damaged valves, prosthetic material, or congenital heart defects. This injury exposes the underlying collagen, leading to the deposition of platelets and fibrin, which form sterile thrombi​.

During episodes of bacteremia, which can be caused by dental procedures, catheterization, or intravenous drug use, bacteria adhere to the damaged endocardium. Common pathogens include Staphylococcus aureus, Streptococcus viridans, and Enterococcus species​. These bacteria use surface adhesins to bind to the thrombi, where they proliferate and form vegetations, which can lead to systemic infection, septic emboli, and valvular destruction​.

Risk Factors

1. Pre-existing Cardiac Conditions

  • Congenital Heart Disease (CHD): Congenital heart defects, such as ventricular septal defects, bicuspid aortic valves, and tetralogy of Fallot, significantly increase the risk of IE in pregnancy. These defects can create abnormal blood flow patterns, leading to endothelial damage and predisposing the heart valves to infection​. CHD remains one of the primary causes of IE in pregnant women, and approximately 0.5% of patients with CHD develop IE during pregnancy​.
  • Prosthetic Valves: The presence of a prosthetic valve is a major risk factor for IE, as the artificial material provides a surface for bacterial adherence during episodes of bacteremia​.. Patients with prosthetic valves are at higher risk of developing IE compared to those with native valves, and they are more likely to suffer from complications such as valve dehiscence and heart failure​(.(1))​.
  • Rheumatic Heart Disease: Although the incidence of rheumatic heart disease has declined in high-income countries, it remains a significant risk factor for IE in low- and middle-income regions​. Women with rheumatic valve disease, particularly those with mitral stenosis or regurgitation, are at increased risk of IE due to the turbulent blood flow across damaged valves​.
  • Previous History of IE: A previous episode of IE significantly increases the risk of recurrence during pregnancy, especially in patients with residual valvular damage or prosthetic valves​.. The recurrence of IE in pregnancy is associated with elevated mortality rates and a higher likelihood of complications such as embolic events and heart failure​.

2. Intravenous Drug Use (IVDU)

  • Intravenous drug use (IVDU) is a major extracardiac risk factor for IE in pregnancy, particularly in high-income countries. IVDU-associated IE typically involves the right side of the heart, especially the tricuspid valve, and is most commonly caused by Staphylococcus aureus​. The frequent use of contaminated needles increases the risk of bacteremia, leading to bacterial colonization of the heart valves and the formation of vegetations​. In recent studies, IVDU has been identified as a risk factor in 23% of pregnancy-related IE cases​.

3. Immunosuppression

  • Pregnancy-related immune modulation: Pregnancy is associated with a state of relative immunosuppression, characterized by reduced adaptive immunity and an increased reliance on innate immune responses. This immunological shift helps protect the fetus from maternal immune rejection but also renders the mother more susceptible to infections, including bacteremia and endocarditis​. Immunosuppression is particularly concerning in women with pre-existing conditions such as HIV or autoimmune diseases​.
  • Comorbid Conditions: Conditions such as diabetes mellitus, chronic kidney disease, and long-term use of immunosuppressive medications further weaken the immune system, increasing the likelihood of bacteremia and subsequent IE​.)​. Hemodialysis patients are also at risk due to frequent venous access and the potential for bloodstream infections​.

4. Invasive Procedures

  • Dental and Surgical Procedures: Dental procedures that involve manipulation of the gums or oral mucosa can introduce bacteria into the bloodstream, leading to transient bacteremia, especially in patients with pre-existing heart disease​.. In pregnant women with prosthetic valves or congenital heart defects, this bacteremia can result in bacterial adherence to damaged endocardial surfaces, increasing the risk of IE.
  • Catheterization and Obstetric Procedures: Invasive procedures such as urinary catheterization, amniocentesis, and cesarean sections can increase the risk of bacteremia during pregnancy, particularly if aseptic technique is compromised​. Additionally, prolonged labor, membrane rupture, and manual removal of the placenta can contribute to an increased risk of IE​.

5. Socioeconomic and Healthcare Factors

  • Access to Healthcare: In low- and middle-income countries, delays in accessing healthcare and limited availability of diagnostic tools contribute to a higher incidence of IE-related complications and mortality​.. In contrast, high-income countries have seen an increase in healthcare-associated infections due to the greater use of invasive cardiac devices and prolonged hospitalizations​.
  • Poor Dental Hygiene: Poor dental hygiene and the absence of prophylactic measures during dental procedures increase the risk of bacteremia and subsequent IE, particularly in women with predisposing heart conditions​.

6. Pregnancy-related Changes

  • Hemodynamic Stress: Pregnancy induces significant changes in cardiovascular function, including increased cardiac output and blood volume, which place additional stress on the heart valves, especially in women with pre-existing valve disease​(.(1))​. The increased shear stress across abnormal or prosthetic valves can lead to endothelial injury, creating a favorable environment for bacterial colonization during episodes of bacteremia​.

Clinical Presentation

1. Common Symptoms

  • Fever: Persistent low-grade fever is the most frequent symptom of IE, occurring in more than 90% of cases​​. In pregnancy, however, mild fevers are often attributed to common infections such as urinary tract infections or viral illnesses, which can complicate the early recognition of IE​.
  • Fatigue and malaise: Generalized fatigue and malaise are common in pregnancy but may also indicate a systemic infection such as IE​. Pregnant women who report worsening fatigue, particularly when associated with fever or other systemic signs, should be evaluated for potential underlying infections.
  • Dyspnea and orthopnea: Shortness of breath and orthopnea, particularly in the later stages of pregnancy, can be symptoms of normal physiological changes. However, in women with underlying heart disease, these may be signs of progressive valve dysfunction or heart failure due to IE​. Acute or worsening dyspnea should prompt further cardiac evaluation.
  • Myalgias and arthralgias: Musculoskeletal pain, including myalgias and arthralgias, can also occur as part of the systemic inflammatory response in IE. These symptoms may be misattributed to the general discomforts of pregnancy or other causes​..

2. Cardiac Manifestations

  • New or worsening heart murmur: A new or changing heart murmur is a key finding in patients with IE, particularly in those with congenital heart disease, prosthetic valves, or a history of rheumatic heart disease​.. Pregnancy itself can induce benign flow murmurs, making it essential to carefully assess any new murmurs, especially diastolic murmurs or those that change during pregnancy​.
  • Heart failure: Heart failure due to valvular destruction is one of the most serious complications of IE​. Signs of heart failure such as peripheral edema, orthopnea, and paroxysmal nocturnal dyspnea should be investigated with echocardiography to assess for valve dysfunction.
  • Palpitations and arrhythmias: Pregnant women with IE may experience palpitations or arrhythmias due to bacterial involvement of the myocardium or septic emboli. These symptoms may reflect the onset of new or worsening valvular disease​.

3. Embolic Manifestations

Embolization of infected vegetations is a common complication of IE, which can result in systemic embolic events depending on the location of the infection:

  • Cerebrovascular events: Pregnant women with left-sided IE are at high risk for embolic strokes, which can present with sudden-onset neurological deficits such as hemiparesis, aphasia, or visual disturbances​(.(1))​. These strokes can have devastating effects on both maternal and fetal outcomes.
  • Septic pulmonary emboli: Right-sided IE, commonly associated with intravenous drug use, may lead to septic pulmonary emboli. These present with pleuritic chest pain, hemoptysis, and respiratory distress, mimicking pulmonary embolism or pneumonia​(.…)​..
  • Renal and splenic embolization: Systemic emboli can also lodge in the kidneys or spleen, causing flank pain, hematuria, or abdominal pain. Pregnant women with unexplained flank or abdominal pain, particularly if associated with fever, should be evaluated for possible embolic events​.
  • Cutaneous signs: Classic signs of IE such as Janeway lesions (painless macular lesions on the palms or soles) and Osler nodes (painful nodules on the fingertips or toes) are rare but pathognomonic findings when present​. Other dermatologic findings such as petechiae and splinter hemorrhages may be observed, especially in cases of subacute IE​.

Diagnostic Approach

1. Clinical Evaluation

A thorough clinical evaluation is essential in suspected cases of IE. The evaluation should include:

  • Detailed medical history: Key elements include a history of congenital or acquired heart disease, previous endocarditis, intravenous drug use, recent invasive procedures, or dental work​. Any pregnant woman presenting with fever and new or worsening heart murmurs should be evaluated for IE, particularly if risk factors are present.
  • Physical examination: Physical findings suggestive of IE include new or changing heart murmurs, signs of heart failure (e.g., jugular venous distension, peripheral edema), and embolic phenomena such as Janeway lesions, Osler nodes, splinter hemorrhages, or petechiae​.  The presence of these findings warrants further investigation.

2. Blood Cultures

Blood cultures remain the cornerstone of diagnosing IE, and they should be obtained before initiating antibiotic therapy. The following principles should be followed:

  • Number of cultures: At least three sets of blood cultures from different venipuncture sites should be drawn, ideally spaced at least one hour apart to maximize the chances of isolating the causative organism​. This approach helps detect the presence of bacteremia, which is critical for confirming the diagnosis of IE.
  • Pathogens: Common pathogens in pregnancy-related IE include Staphylococcus aureus, Streptococcus viridans, and Enterococcus species. Staphylococcus aureus is particularly common in cases of intravenous drug use-related IE​.)​. In some cases, blood cultures may be negative, particularly if the patient has received prior antibiotic therapy, necessitating further diagnostic steps.

3. Echocardiography

Echocardiography is the key imaging modality for diagnosing and assessing the severity of IE. Two types of echocardiography are commonly used:

  • Transthoracic echocardiography (TTE): TTE is typically the first-line imaging study due to its non-invasive nature and safety in pregnancy. However, its sensitivity in detecting small vegetations or assessing prosthetic valves is limited​..
  • Transesophageal echocardiography (TEE): TEE is more sensitive than TTE and is recommended for pregnant women at high risk for IE or those with inconclusive TTE findings. TEE is particularly useful for visualizing vegetations, abscesses, and prosthetic valve dysfunction​(.(1))​. The safety of TEE in pregnancy has been well established, though care should be taken to avoid maternal hypotension during the procedure​.

4. Modified Duke Criteria

The Modified Duke Criteria are used to establish the diagnosis of IE by integrating clinical, microbiological, and echocardiographic findings. These criteria classify the diagnosis into definitive, possible, or rejected categories based on major and minor criteria:

  • Major criteria:
    1. Positive blood cultures with typical organisms consistent with IE (e.g., Staphylococcus aureus, Streptococcus viridans.
    2. Evidence of endocardial involvement on echocardiography (e.g., vegetation, abscess, new valvular regurgitation.
  • Minor criteria:
    1. Predisposing heart condition or intravenous drug use.
    2. Fever (≥38°C.
    3. Vascular phenomena (e.g., systemic emboli, Janeway lesions.
    4. Immunological phenomena (e.g., glomerulonephritis, Osler nodes.
    5. Positive blood cultures not meeting the major criteria.

A definitive diagnosis of IE is made if two major criteria, one major and three minor criteria, or five minor criteria are present​..

5. Additional Imaging

In certain cases, additional imaging modalities may be necessary to evaluate complications such as embolic events or abscess formation. However, fetal safety considerations often limit the use of some imaging techniques.

  • Magnetic Resonance Imaging (MRI): MRI, without gadolinium contrast, can be safely used during pregnancy to assess for complications such as embolic strokes, brain abscesses, or mycotic aneurysms. MRI is also useful for detecting splenic or renal infarcts​(.(1))​.
  • Computed Tomography (CT): While CT scans are not routinely recommended during pregnancy due to the risks of fetal radiation exposure, they may be necessary in select cases (e.g., suspected septic pulmonary embolism. When CT is used, appropriate fetal shielding should be employed to minimize radiation exposure​.

6. Laboratory Testing

Laboratory tests can provide supportive evidence for the diagnosis of IE, though none are specific. Common findings include:

  • Elevated inflammatory markers: C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are typically elevated in IE, reflecting the systemic inflammatory response to infection​..
  • Complete Blood Count (CBC): Normocytic, normochromic anemia and leukocytosis are common in IE​. Thrombocytopenia may also be present in cases of septic emboli or disseminated intravascular coagulation (DIC.
  • Renal function tests: Elevated serum creatinine and urea may indicate renal involvement, either due to septic emboli or acute kidney injury associated with sepsis​.
  • Urinalysis: Hematuria or proteinuria may suggest embolic or immune complex-related glomerulonephritis, which can occur in IE​.)​.

7. Novel Diagnostic Methods

Recent advancements in molecular diagnostics have improved the identification of pathogens in IE, particularly in cases of culture-negative endocarditis:

  • Cell-free DNA sequencing: This cutting-edge diagnostic tool allows for the detection of microbial DNA in the bloodstream, offering a rapid and non-invasive method for identifying pathogens, especially when blood cultures are negative​. Although not widely available, this method holds promise for the future of IE diagnosis, particularly in pregnant women.
  • Metagenomic next-generation sequencing: This technology has demonstrated superior sensitivity compared to traditional blood cultures, enabling the identification of rare or fastidious organisms that may be missed by conventional methods​. However, its high cost and limited availability restrict its use in routine practice.

Management 

1. Multidisciplinary Approach

Optimal management of IE in pregnancy necessitates a multidisciplinary team involving cardiologists, obstetricians, infectious disease specialists, and, when necessary, cardiac surgeons and neonatologists. The timing of treatment interventions, including surgery and delivery, must be coordinated between all relevant specialists to ensure the best possible outcomes for both the mother and the fetus

2. Antibiotic Therapy

The cornerstone of IE management is prolonged antibiotic therapy. The choice of antibiotic regimen is guided by the causative organism, susceptibility patterns, and the safety profile of the antibiotics during pregnancy. Empiric therapy should be started after blood cultures have been drawn, and adjustments should be made based on culture results and sensitivity testing​(.…)​..

The following table outlines commonly used antibiotics and their recommended dosages in pregnancy, based on the causative organism:

Causative OrganismAntibiotic RegimenDosageDuration
Streptococcus viridansPenicillin G or ceftriaxone, with or without gentamicin– Penicillin G: 12-18 million U/day IV in divided doses every 4 hours
– Ceftriaxone: 2 g/day IV
4-6 weeks
Gentamicin (if indicated)– Gentamicin: 3 mg/kg/day IV or IM in divided doses every 8 hours2 weeks
Staphylococcus aureus (Methicillin-sensitive)Nafcillin or oxacillin– Nafcillin or oxacillin: 12 g/day IV in divided doses every 4 hours4-6 weeks
Staphylococcus aureus (Methicillin-resistant)Vancomycin– Vancomycin: 15-20 mg/kg IV every 8-12 hours, adjusted to maintain serum trough levels of 15-20 µg/mL4-6 weeks
Enterococcus speciesAmpicillin or penicillin G, with or without gentamicin– Ampicillin: 12 g/day IV in divided doses every 4-6 hours
– Penicillin G: 18-30 million U/day IV
4-6 weeks
Prosthetic valve IECombination therapy of vancomycin, gentamicin, and rifampin– Vancomycin: 15-20 mg/kg IV every 8-12 hours
– Gentamicin: 3 mg/kg/day IV/IM
– Rifampin: 300 mg orally every 8 hours
6+ weeks, depending on clinical response
  • Empiric Therapy: In cases where the causative organism is not immediately identified, empiric antibiotic therapy should cover both Staphylococcus aureus (including methicillin-resistant strains) and Streptococcus viridans.
    • Recommended empiric regimen: vancomycin (15-20 mg/kg IV every 8-12 hours) plus ceftriaxone (2 g/day IV), with dose adjustments based on weight and renal function​(.(1))​..

3. Antibiotic Considerations in Pregnancy

  • Penicillins and Cephalosporins: These are the preferred antibiotics in pregnancy due to their long-standing safety profiles. Both penicillin G and ceftriaxone are safe and effective for treating IE in pregnancy​..
  • Vancomycin: Vancomycin is considered safe in pregnancy and is often used for methicillin-resistant Staphylococcus aureus (MRSA) infections. However, serum levels should be carefully monitored to avoid toxicity​.
  • Aminoglycosides (e.g., Gentamicin): Aminoglycosides should be used with caution during pregnancy due to the potential risk of ototoxicity and nephrotoxicity, particularly in the fetus. When used, aminoglycosides should be given for the shortest duration possible (usually 2 weeks) and only when benefits outweigh the risks​..
  • Rifampin: Rifampin is used in cases of prosthetic valve endocarditis and in combination with other antibiotics. Although generally avoided in early pregnancy due to concerns of teratogenicity, it may be used in later stages under close monitoring​.

4. Surgical Intervention

Approximately 50% of patients with IE will require surgical intervention during the course of their disease​.)​. Surgery may be indicated in cases of:

  • Heart failure due to severe valvular regurgitation.
  • Uncontrolled infection, despite appropriate antibiotic therapy.
  • Embolic events, particularly with large vegetations (>10 mm) or recurrent embolization.
  • Prosthetic valve dysfunction, such as dehiscence or obstruction​.

The decision to perform surgery in a pregnant woman must consider both maternal and fetal risks. Surgery is generally delayed until after delivery if possible, but in cases of life-threatening complications, urgent valve surgery may be necessary​.

  • Cardiopulmonary bypass during pregnancy is associated with a significant risk of fetal loss (up to 20%), particularly in the second trimester​.. If surgery is needed, a multidisciplinary team should evaluate the timing of delivery, with consideration of preterm cesarean section prior to maternal surgery in the third trimester​.

5. Timing of Delivery

The timing of delivery is a critical component of managing IE in pregnant women. In general, delivery is delayed until after the infection is controlled, but certain scenarios may necessitate earlier delivery​.

  • Elective preterm delivery: In women with severe IE requiring surgery or in those with uncontrolled infection, preterm delivery by cesarean section may be performed to reduce the risks of fetal complications​.
  • Vaginal delivery: In women with well-controlled IE who have completed antibiotic therapy, vaginal delivery is preferred to minimize maternal risks associated with cesarean section​..

6. Anticoagulation in Prosthetic Valve Patients

Pregnant women with prosthetic valves often require anticoagulation therapy, which adds complexity to the management of IE​. Decisions regarding anticoagulation must balance the risk of thromboembolism with the risk of bleeding, particularly in the setting of valve surgery or cesarean delivery.

  • Low molecular weight heparin (LMWH) is preferred during pregnancy due to its safety profile​. However, anticoagulation should be carefully managed perioperatively if surgery is indicated.

Maternal and Fetal Outcomes 

1. Maternal Outcomes

  • Mortality: Maternal mortality rates in pregnancy-associated IE range from 22% to 33%​.)​. The primary causes of maternal death include heart failure, systemic embolization (e.g., stroke, splenic infarct), sepsis, and complications related to valve dysfunction. Timely intervention, particularly early initiation of appropriate antibiotic therapy and surgery when indicated, is critical in reducing mortality.
  • Morbidity: Significant maternal morbidity is common, particularly in those with underlying heart disease or prosthetic valves. The major complications include:
    • Heart failure: Valvular destruction due to IE can lead to acute valvular insufficiency, which may progress to heart failure​..
    • Systemic emboli: Embolic phenomena such as stroke, renal infarcts, and limb ischemia can significantly impair maternal health​.
    • Valve replacement: Many women require valve surgery, which carries a high risk during pregnancy, particularly due to the need for cardiopulmonary bypass​.
  • Postpartum complications: Postpartum women who have been treated for IE may be at risk for recurrent infection, especially if prosthetic material is involved. Additionally, postpartum hemorrhage may be more common in women who are anticoagulated due to prosthetic valves​.

2. Fetal Outcomes

  • Fetal Mortality: Fetal mortality in IE ranges from 14% to 29%​.)​. Fetal death can result from maternal hemodynamic instability, systemic infection, or placental insufficiency caused by embolic events affecting placental circulation​. Preterm labor, often necessary due to maternal indications for surgery, contributes significantly to the high fetal mortality rate.
  • Preterm Birth: Preterm delivery is a frequent complication in pregnant women with IE, often due to the need for early delivery to facilitate maternal surgery or due to spontaneous preterm labor triggered by systemic inflammation and infection​. Preterm birth can lead to significant neonatal morbidity, including respiratory distress syndrome, intraventricular hemorrhage, and necrotizing enterocolitis.
  • Intrauterine Growth Restriction (IUGR): Maternal hemodynamic instability and infection can result in placental insufficiency, leading to IUGR. Fetuses exposed to prolonged maternal illness or systemic embolic events are at particular risk​.)​.
  • Neonatal Sepsis: Although rare, vertical transmission of bacteria causing IE can lead to neonatal infection. This is more likely in cases where maternal bacteremia is prolonged and not well controlled​.

3. Long-Term Outcomes

  • Maternal Long-term Outcomes: Women who survive IE during pregnancy often require long-term follow-up for their underlying heart disease, particularly if valve surgery was performed. Recurrence of IE is possible, particularly in those with prosthetic valves or persistent predisposing conditions (e.g., intravenous drug use)​.
  • Fetal and Neonatal Outcomes: Preterm infants may face long-term complications related to prematurity, such as neurodevelopmental delays or chronic lung disease. Follow-up in neonatal intensive care units (NICUs) is essential for optimizing outcomes​.)​.

Obstetric Management of Infective Endocarditis

1. Timing of Delivery

The timing of delivery in women with IE depends on the gestational age, the severity of the infection, and the need for maternal cardiac surgery. The decision is typically made by a multidisciplinary team based on maternal and fetal risks.

  • Early Delivery: In cases of uncontrolled infection, heart failure, or the need for urgent valve surgery, early delivery by cesarean section may be indicated, particularly if the pregnancy is beyond 32 weeks​. Preterm delivery is often necessary to stabilize the mother before cardiac surgery​..
  • Expectant Management: If the infection is well-controlled with antibiotics and the maternal condition is stable, pregnancy can be allowed to continue to term. In these cases, vaginal delivery is generally preferred unless there are obstetric indications for cesarean section​.

2. Mode of Delivery

  • Vaginal Delivery: Vaginal delivery is preferred in women with well-controlled IE, as it minimizes the risks associated with surgery and anesthesia​.. However, careful monitoring is required during labor, particularly in women with prosthetic valves or significant valvular dysfunction. Endocarditis prophylaxis with antibiotics should be given during labor to prevent bacteremia​.
  • Cesarean Section: Cesarean delivery is indicated in cases where maternal instability necessitates early delivery or in women who require immediate surgical intervention for valve repair or replacement​. It may also be necessary in women with severe valvular disease or mechanical prostheses who cannot tolerate the hemodynamic changes of labor​.

3. Management During Labor and Delivery

  • Antibiotic Prophylaxis: Antibiotic prophylaxis should be administered during labor and delivery to reduce the risk of bacteremia, particularly in women with prosthetic valves, congenital heart disease, or a history of IE​.)​. The choice of antibiotics depends on the causative organism of the IE and the patient’s allergy history.
  • Hemodynamic Monitoring: Continuous hemodynamic monitoring is essential during labor and delivery, particularly in women with significant valve dysfunction or heart failure​. Epidural anesthesia can be safely used in most cases, but general anesthesia may be necessary for cesarean sections if maternal hemodynamics are unstable.
  • Anticoagulation Management: Women with prosthetic valves who are on anticoagulation therapy require careful management during delivery to balance the risk of thromboembolism with the risk of bleeding. Low-molecular-weight heparin (LMWH) is generally preferred during pregnancy, but anticoagulation should be held during labor and resumed postpartum​.

4. Postpartum Management

  • Continued Antibiotic Therapy: Antibiotic therapy should be continued postpartum to ensure the complete eradication of the infection, especially in women with prosthetic valves or persistent bacteremia​. The total duration of therapy is typically 4 to 6 weeks but may be longer depending on the severity of the infection.
  • Contraception Counseling: Postpartum contraception is crucial for women with IE, particularly those with underlying heart disease. Future pregnancies may carry a high risk of recurrence or worsening of cardiac function​.

Infective Endocarditis Prophylaxis in Pregnancy

1. Indications for IE Prophylaxis in Pregnancy

The indications for IE prophylaxis during pregnancy follow the same guidelines as for the general population. The American Heart Association (AHA) and European Society of Cardiology (ESC) guidelines recommend prophylaxis only for patients with the highest risk for adverse outcomes from IE. These high-risk groups include:

  • Prosthetic heart valves: Mechanical or bioprosthetic valves or patients with a history of valve repair using prosthetic material​.)​.
  • Previous history of infective endocarditis: Patients with a prior history of IE are at high risk of recurrence, especially during pregnancy​.
  • Congenital heart disease (CHD):
    • Unrepaired cyanotic congenital heart disease, including palliative shunts and conduits.
    • Completely repaired congenital heart disease with prosthetic material during the first six months after the procedure.
    • Repaired congenital heart disease with residual defects at or adjacent to the site of a prosthetic patch or device​..
  • Cardiac transplant recipients with valvulopathy: Patients who have developed valve disease after heart transplantation are also considered high-risk and require prophylaxis​(.…)​.

2. Procedures Requiring IE Prophylaxis

The AHA and ESC guidelines specify that IE prophylaxis is recommended for high-risk patients undergoing certain procedures that are likely to cause transient bacteremia:

  • Dental procedures: Prophylaxis is recommended for all dental procedures that involve manipulation of the gingival tissue, periapical region of teeth, or perforation of the oral mucosa​(.…)​.. Routine dental cleanings and scaling fall into this category.
  • Respiratory tract procedures: Prophylaxis is indicated for procedures that involve incision or biopsy of the respiratory mucosa, such as tonsillectomy, adenoidectomy, or bronchoscopy with biopsy​.
  • Gastrointestinal or genitourinary procedures: IE prophylaxis is generally not recommended for GI or GU procedures (e.g., colonoscopy, cystoscopy), even in high-risk patients, unless the patient has an active infection such as a UTI​.. However, individual considerations may apply, particularly in patients with significant valvular disease or prosthetic valves.
  • Intrapartum care: Routine vaginal delivery and cesarean section do not require IE prophylaxis unless there are risk factors such as infection during labor (e.g., chorioamnionitis)​.

3. Recommended Antibiotic Regimens for IE Prophylaxis in Pregnancy

The following antibiotic regimens are recommended for IE prophylaxis in pregnant women undergoing high-risk procedures:

AntibioticRegimen
Amoxicillin2 g orally 30-60 minutes before the procedure
Ampicillin2 g IV or IM 30-60 minutes before the procedure
If allergic to penicillin:
Clindamycin600 mg orally or IV 30-60 minutes before the procedure
Cefazolin or ceftriaxone1 g IV or IM 30-60 minutes before the procedure
  • Oral regimen: Amoxicillin (2 g orally) is the first-line oral regimen for prophylaxis. In patients with a penicillin allergy, clindamycin (600 mg orally) is recommended​(.…)​.
  • Intravenous regimen: For patients who cannot take oral medications, ampicillin (2 g IV or IM) is the preferred regimen. Clindamycin (600 mg IV) or cefazolin (1 g IV) can be used as alternatives for those with penicillin allergies​.

4. Special Considerations in Pregnancy

  • Fetal safety: The antibiotics recommended for IE prophylaxis in pregnancy (e.g., amoxicillin, ampicillin, cefazolin, clindamycin) are considered safe for both the mother and fetus when used in the short term​.. However, aminoglycosides (e.g., gentamicin) should be avoided in prophylaxis due to the risk of ototoxicity and nephrotoxicity in the fetus​.
  • Dental care: Good oral hygiene and routine dental care are crucial in preventing bacteremia during pregnancy. High-risk patients should be advised to undergo routine dental checkups, with IE prophylaxis administered before invasive dental procedures​.

5. Obstetric Considerations

  • Delivery: Prophylaxis is not routinely recommended during labor and delivery unless there are specific concerns such as active infection (e.g., chorioamnionitis) or if the patient has a history of IE or a high-risk cardiac condition​. For high-risk patients, antibiotic prophylaxis may be considered during prolonged labor, manual removal of the placenta, or cesarean section​.

REFERENCES

  1. Otto CM, Nishimura RA, Bonow RO, Carabello BA, Erwin JP 3rd, Gentile F, et al. 2020 ACC/AHA guideline for the management of patients with valvular heart disease: A report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2021 Feb 2;143(5)
  2. Botéa A, Grigoriu M, Tudorache S, Popescu C, Mărginean A, Cotuţiu C, et al. Infective endocarditis in a third-trimester pregnant woman: Case report and literature review. Rom J Morphol Embryol. 2020;61(1):275-80.
  3. Tan R, Chiew RF, Foong LH, Lim LY, Chua SJ. Infective endocarditis in pregnancy: A case report and review of the literature. Case Rep Womens Health. 2021;32
  4. Fessl I, Naumann M, Helmig F, Fessl B, Schreyögg J, Kesselmeier M, et al. Challenges of infective endocarditis in pregnancy: A case report and review of the literature. BMC Pregnancy Childbirth. 2020 Sep 7;20(1):523.