What is the best management approach for a pregnant woman with rheumatic heart disease?

Management of Rheumatic Heart Disease in Pregnancy

Pregnant women with rheumatic heart disease require immediate multidisciplinary cardio-obstetric team management at a specialized center, with the primary goals being preconception risk stratification when possible, aggressive medical therapy with beta-blockers and diuretics during pregnancy, and careful monitoring through the high-risk periods of 24-32 weeks gestation and the first 48 hours postpartum. 1, 2

Immediate Risk Stratification and Assessment

Perform urgent echocardiography to assess:

• Mitral valve area (MVA) - severe stenosis defined as MVA ≤1.5 cm² 1
• Pulmonary artery systolic pressure (PASP) - severe pulmonary hypertension ≥50 mmHg carries 17-33% maternal mortality risk 1, 2
• Left atrial size and presence of spontaneous echo contrast 1
• Degree of valve regurgitation if present 3

The severity of mitral stenosis and presence of pulmonary hypertension are the two most critical prognostic factors that determine maternal mortality risk. 1, 2

Multidisciplinary Team Assembly

Assemble a pregnancy heart team immediately consisting of: 2, 3, 4

• Maternal-fetal medicine specialist (lead obstetric care)
• Cardiologist with valvular disease expertise
• Obstetric anesthesiologist
• Neonatologist
• Cardiac surgeon (on standby for emergencies)

This is non-negotiable for all pregnant women with rheumatic heart disease, regardless of symptom severity, because approximately 49% of serious cardiac events are preventable with proper team management. 5

Medical Management During Pregnancy

Beta-Blockers: Cornerstone of Therapy

Beta-blockers are the first-line medical therapy and should be initiated or continued in all patients with mitral stenosis. 1, 2, 3

• Control heart rate to optimize diastolic filling time across the stenotic valve 2
• Metoprolol or atenolol are preferred agents (pregnancy category C but extensive safety data) 1
• Target heart rate 60-80 bpm at rest 3

Diuretics for Volume Management

Use diuretics cautiously for pulmonary congestion, but avoid excessive volume depletion that compromises uteroplacental perfusion. 1, 2

• Furosemide is the preferred agent for acute pulmonary edema 2
• Monitor for signs of placental insufficiency (fetal growth restriction) 2

Anticoagulation Strategy

For patients in atrial fibrillation or with very severe left atrial enlargement with spontaneous echo contrast: 1

• Therapeutic anticoagulation is required throughout pregnancy
• Avoid warfarin in first trimester (teratogenic) and after 36 weeks (fetal bleeding risk)
• Use low molecular weight heparin in first trimester and near delivery 1

Absolutely Contraindicated Medications

ACE inhibitors and angiotensin receptor blockers are absolutely contraindicated throughout pregnancy due to fetal renal toxicity and teratogenicity. 2

Critical High-Risk Periods Requiring Intensified Monitoring

Peak Hemodynamic Stress: 24-32 Weeks Gestation

This period represents maximum cardiac output (30-50% above baseline) and plasma volume expansion (40% increase), placing greatest stress on stenotic valves. 2, 6

• Weekly cardiology assessments during this window 2
• Lower threshold for hospital admission if symptoms worsen 3
• Consider elective admission for severe stenosis (MVA <1.0 cm²) 1

Labor and Immediate Postpartum: Second Critical Window

The first 24-48 hours postpartum represent a second high-risk period with significant hemodynamic shifts. 2, 3

• Autotransfusion from uterine contraction increases preload acutely 2
• Administer single IV dose furosemide 20-40 mg immediately after delivery 2
• Continuous cardiac monitoring for 48 hours postpartum 3

Interventional Procedures During Pregnancy

Percutaneous Balloon Mitral Valvuloplasty (PBMC)

PBMC should be performed after 20 weeks gestation in experienced centers for patients with moderate-severe MS (MVA <1.5 cm²) who remain symptomatic (NYHA III-IV) despite aggressive medical therapy. 1, 2

• Optimal timing is around 25 weeks gestation when technically feasible 2
• Requires favorable valve morphology (pliable leaflets, minimal calcification, minimal regurgitation) 1
• Perform only at comprehensive valve centers with fetal monitoring capability 1

Cardiac Surgery During Pregnancy

Cardiac surgery during pregnancy carries up to 30% fetal mortality risk and should be reserved only for life-threatening maternal conditions refractory to all other measures. 2

• This includes refractory heart failure, severe aortic stenosis with syncope, or acute valve thrombosis 2

Labor and Delivery Planning

Mode of Delivery

Vaginal delivery is preferred for most women with rheumatic heart disease, including those with compensated mitral stenosis. 2, 3

Cesarean section is recommended for: 1

• Severe mitral stenosis with poor clinical state (NYHA IV)
• Severe pulmonary hypertension (PASP >80 mmHg)
• Women on oral anticoagulants in preterm labor
• Standard obstetric indications

Anesthesia Strategy

Epidural analgesia is strongly preferred as it provides pain control, reduces catecholamine surge, and stabilizes cardiac output. 2

• Avoid general anesthesia unless absolutely necessary (higher hemodynamic instability) 3
• Avoid spinal anesthesia in severe stenosis (rapid vasodilation poorly tolerated) 3

Rheumatic Fever Prophylaxis

Continue lifelong secondary prophylaxis against rheumatic fever throughout pregnancy and postpartum: 1

• Benzathine penicillin G 1.2 million units IM every 3-4 weeks (preferred) 1
• For severe RHD: minimum 10 years after most recent acute rheumatic fever or until age 40 (whichever is longer) 1
• For moderate RHD: minimum 10 years or until age 35 1

Preconception Counseling for Future Pregnancies

Pregnancy may be contraindicated in women with: 1, 2

• Severe pulmonary hypertension (mortality 17-33%)
• Severe symptomatic mitral or aortic stenosis (NYHA class III-IV)
• MVA <1.0 cm² without prior intervention 1

For women considering future pregnancy, PBMC should be performed before conception in those with moderate-severe MS (MVA ≤1.5 cm²). 1

Common Pitfalls to Avoid

Do not dismiss dyspnea as "normal pregnancy fatigue" in patients with known or suspected rheumatic heart disease. 2, 6

• Rheumatic heart disease is now rare in Western countries except in immigrants, leading to missed diagnoses 2
• Any pregnant woman with unexplained dyspnea and a diastolic murmur requires urgent echocardiography 2

Do not delay intervention in symptomatic patients hoping medical therapy alone will suffice through delivery. 1, 3

• Persistent NYHA III-IV symptoms despite beta-blockers and diuretics mandate consideration of PBMC 1
• Maternal mortality risk with untreated severe symptomatic stenosis exceeds procedural risk of PBMC after 20 weeks 2

Do not underestimate the postpartum period as a time of continued high risk. 2, 3

• Most maternal deaths occur postpartum, not during labor 3
• Maintain intensive monitoring and diuretic therapy for at least 48 hours after delivery 2