How to manage a 34-year-old pregnant woman at 23 weeks gestation with atrial septal defect (ASD) and pulmonary hypertension, currently on tadalafil (phosphodiesterase type 5 inhibitor), who desires to continue the pregnancy and presented with hypoxia and bidirectional shunt?

Management of a 34-Year-Old Pregnant Woman with ASD and Pulmonary Hypertension

This patient with severe pulmonary hypertension (RVSP 80 mmHg) and ASD with bidirectional shunt should be managed at a tertiary center with PAH expertise, as she faces extremely high maternal mortality risk (17-33% in recent studies) if pregnancy continues. 1

Current Assessment and Diagnosis

• Diagnosis: Atrial Septal Defect with severe pulmonary arterial hypertension (PAH-CHD) and bidirectional shunt
• Current status: 23 weeks pregnant, post-extubation hypoxia (SpO2 86%), RVSP 80 mmHg
• Current therapy: Tadalafil (PDE-5 inhibitor)

Management Plan for Continued Pregnancy

Immediate Actions

1. Transfer to specialized center: Patient must be transferred to a tertiary center with expertise in PAH and high-risk obstetrics 1

2. Escalate PAH therapy:

   • Continue tadalafil
   • Consider adding prostacyclin (IV epoprostenol or inhaled iloprost) 1
   • Consider adding endothelin receptor antagonist (ambrisentan) for triple therapy 2
   • Note: Bosentan should be avoided due to teratogenic effects 1

3. Supplemental oxygen: Maintain maternal oxygen saturation >95% to ensure adequate fetal oxygenation 1, 3

Hospital Management

1. Positioning: Left lateral positioning to prevent inferior vena cava compression 1, 3

2. Anticoagulation:

   • Consider LMWH or UFH if indicated for pulmonary thrombosis risk or heart failure signs 1
   • Monitor anti-Xa levels for LMWH or aPTT for UFH 1

3. Volume management:

   • Maintain adequate circulating volume
   • Avoid systemic hypotension, hypoxia, and acidosis which may precipitate refractory heart failure 1

4. Monitoring:

   • Daily vital signs with continuous oxygen saturation monitoring
   • Weekly echocardiography to assess pulmonary pressures and right ventricular function
   • Regular assessment of fetal well-being with electronic fetal monitoring 1, 3

Follow-up Plan Until Delivery

1. Multidisciplinary team involvement:

   • Pulmonary hypertension specialist
   • High-risk obstetrics
   • Neonatology
   • Cardiac anesthesiology
   • Intensive care

2. Maternal monitoring:

   • Weekly clinical assessment
   • Monthly echocardiography to assess RVSP and right ventricular function
   • Regular arterial blood gases if hypoxemia persists

3. Fetal monitoring:

   • Regular ultrasound for fetal growth (every 2-3 weeks)
   • Weekly fetal heart rate monitoring
   • Antenatal corticosteroids at 24 weeks for fetal lung maturation

4. Delivery planning:

   • Target delivery at 32-34 weeks after antenatal corticosteroids
   • Planned cesarean section under regional anesthesia with careful hemodynamic monitoring 1
   • Avoid general anesthesia if possible (risk factor for maternal death) 1
   • Have prostacyclin available for peripartum period 1

Post-delivery Management

1. Intensive monitoring: ICU admission for at least 72 hours post-delivery 1

   • Highest risk period is immediate postpartum and first few months after delivery
   • Risk of pulmonary hypertensive crisis, pulmonary thrombosis, or refractory right heart failure

2. Continue PAH therapy: Maintain or escalate PAH-specific therapy as needed 1

3. Anticoagulation: Consider postpartum thromboprophylaxis 1

Important Considerations and Pitfalls

1. High maternal mortality risk: The patient must understand that maternal mortality remains high (17-33%) despite optimal management 1

2. Risk of shunt inversion: Be vigilant for right-to-left shunt worsening, which can cause severe hypoxemia, as reported in similar cases 2

3. Avoid vasopressors: Use only for intractable hypotension unresponsive to fluid resuscitation due to adverse effects on uteroplacental perfusion 3

4. Hemodynamic instability: The postpartum period carries the highest risk for decompensation due to fluid shifts and hemodynamic changes 1

5. Long-term planning: After successful delivery, discuss contraception and future pregnancy avoidance due to extremely high risk 1

The management of this patient represents one of the highest-risk scenarios in pregnancy. Despite the grave prognosis, some case reports have documented successful outcomes with intensive management and multidisciplinary care in specialized centers 2.