What is the appropriate antenatal follow‑up plan for a pregnant woman with known rheumatic heart disease to keep her cardiac status stable, prevent rheumatic fever recurrences, and ensure a safe delivery?

Antenatal Follow-Up for Pregnant Women with Rheumatic Heart Disease

Pregnant women with known rheumatic heart disease require multidisciplinary cardio-obstetric team management at a specialized center, with monthly cardiology visits until 28 weeks, then every 2 weeks until 36 weeks, followed by weekly visits until delivery, combined with continuous secondary antibiotic prophylaxis and aggressive medical therapy targeting the high-risk periods of 24-32 weeks gestation and the first 48 hours postpartum. 1

Multidisciplinary Team Structure

• Establish care immediately with an interdisciplinary team including cardiologists, maternal-fetal medicine specialists, obstetric anesthesiologists, and neonatologists at a specialized center capable of managing high-risk cardiac pregnancies. 1
• Arrange shared care protocols with local hospitals for routine visits, maintaining clear escalation pathways to the tertiary center when complications arise. 1

Visit Schedule and Monitoring Frequency

• Schedule cardiology assessments monthly through 28 weeks gestation, then increase to every 2 weeks from 28-36 weeks (the peak hemodynamic stress period), followed by weekly visits from 36 weeks until delivery. 1, 2
• Perform echocardiography at baseline (first visit), at 20 weeks, at 28-32 weeks (peak hemodynamic burden), and whenever clinical deterioration occurs to reassess valve severity, ventricular function, and pulmonary pressures. 1, 2
• Monitor NYHA functional class at every visit, as deterioration from class I-II to III-IV signals high risk for maternal cardiac events and requires immediate intervention. 1, 3

Secondary Prophylaxis Against Rheumatic Fever Recurrence

• Continue intramuscular benzathine penicillin G 1.2 million units every 4 weeks throughout pregnancy and postpartum to prevent acute rheumatic fever recurrence, which could catastrophically worsen valve disease during pregnancy. 4, 5
• For penicillin-allergic patients, substitute oral erythromycin 250 mg twice daily as continuous prophylaxis. 5
• Never discontinue secondary prophylaxis during pregnancy—acute rheumatic fever recurrence during pregnancy carries devastating maternal and fetal consequences. 4, 6

Medical Management to Maintain Cardiac Stability

Beta-Blockers (First-Line for Mitral Stenosis)

• Initiate or continue metoprolol or atenolol in all patients with mitral stenosis to control heart rate and optimize diastolic filling time across the stenotic valve, preventing tachycardia-induced pulmonary edema. 1, 2
• Target resting heart rate 60-80 bpm, as the fixed mitral valve orifice cannot accommodate increased stroke volume, and any tachycardia sharply elevates transvalvular gradients. 1

Diuretics (For Pulmonary Congestion)

• Use furosemide cautiously for symptomatic pulmonary congestion, starting with low doses (20-40 mg daily) and titrating carefully to avoid excessive volume depletion that compromises uteroplacental perfusion. 1, 2
• Monitor for orthostatic symptoms and fetal growth restriction, as over-diuresis reduces placental blood flow. 1

Anticoagulation (For Atrial Fibrillation or Severe Left Atrial Enlargement)

• Switch to therapeutic low-molecular-weight heparin throughout the first trimester and after 36 weeks in patients requiring anticoagulation for atrial fibrillation or spontaneous echo contrast, as warfarin causes embryopathy in the first trimester and fetal hemorrhage near delivery. 1, 6
• Warfarin may be used during weeks 13-36 if the patient has a mechanical valve, but this scenario is distinct from native RHD. 1

Critical High-Risk Periods Requiring Intensified Surveillance

24-32 Weeks Gestation (Peak Hemodynamic Stress)

• Cardiac output peaks at 30-50% above baseline during this window due to maximal stroke volume augmentation, imposing the greatest stress on stenotic valves and precipitating pulmonary edema. 1
• Increase visit frequency to every 2 weeks during this period, with low threshold for echocardiography if symptoms worsen. 1, 2

Labor and Delivery

• Plan vaginal delivery with epidural analgesia as the preferred route for most women with compensated RHD, as epidural reduces catecholamine surge and stabilizes cardiac output. 1, 2
• Reserve cesarean section only for obstetric indications or severe decompensated stenosis with NYHA class IV status. 1, 2
• Avoid ergometrine for third-stage management due to risk of acute hypertension and pulmonary edema; use oxytocin cautiously. 2

First 48 Hours Postpartum (Second High-Risk Window)

• Admit all patients with moderate-severe RHD to a monitored setting for at least 48 hours postpartum, as autotransfusion from uterine involution causes an 80% surge in cardiac output and precipitates acute pulmonary edema. 1, 2
• Administer a single intravenous dose of furosemide 20-40 mg immediately after placental delivery to preempt fluid overload. 1

Indications for Percutaneous Balloon Mitral Valvuloplasty During Pregnancy

• Perform percutaneous balloon mitral commissurotomy after 20 weeks gestation in experienced centers for patients with moderate-severe mitral stenosis (valve area <1.5 cm²) who remain NYHA class III-IV despite maximal medical therapy with beta-blockers and diuretics. 1, 2
• This intervention is safe during pregnancy and dramatically improves maternal and fetal outcomes when medical therapy fails. 1, 3
• Avoid cardiac surgery during pregnancy unless life-threatening maternal conditions exist refractory to all other measures, as fetal mortality approaches 30%. 1

Laboratory and Fetal Monitoring

• Assess complete blood count, renal function, and brain natriuretic peptide at least once per trimester to detect anemia (which worsens tachycardia), renal dysfunction from over-diuresis, or subclinical heart failure. 1
• Perform serial fetal growth ultrasounds every 4 weeks starting at 24 weeks to detect intrauterine growth restriction from chronic maternal hypoxemia or over-diuresis. 2, 3

Common Pitfalls to Avoid

• Do not attribute dyspnea solely to "normal pregnancy"—in women with known RHD, new or worsening dyspnea signals cardiac decompensation requiring urgent echocardiography and intensified therapy. 1
• Do not discontinue beta-blockers due to concerns about fetal bradycardia—uncontrolled maternal tachycardia poses far greater risk to both mother and fetus than appropriately dosed beta-blockade. 1, 2
• Do not delay percutaneous balloon mitral valvuloplasty in symptomatic patients with severe stenosis—maternal mortality risk from untreated severe mitral stenosis exceeds procedural risk. 1, 3
• Do not discharge patients immediately postpartum—the 48-hour postpartum period carries equivalent risk to late third trimester and requires monitored observation. 1, 2