What are the recommendations for a woman with a bicuspid aortic valve and an aortic root diameter of 4.5 cm who is planning to become pregnant?

Management of a Woman with Bicuspid Aortic Valve and Aortic Root Dilation Planning Pregnancy

For a woman with bicuspid aortic valve and aortic root diameter of 4.5 cm who is planning pregnancy, prophylactic aortic root surgery should be considered before conception due to the increased risk of aortic dissection during pregnancy.

Risk Assessment

• Bicuspid aortic valve (BAV) is associated with aortic dilation in approximately 50% of patients, with the dilation often maximal in the distal part of the ascending aorta 1
• Aortic dissection can occur in patients with BAV, although less frequently than in Marfan syndrome patients 1
• An aortic root diameter >4.0 cm confers approximately a 10% risk of dissection during pregnancy 2
• A diameter of 4.0-4.4 cm is associated with an 89-fold increased risk of dissection compared to normal aortic diameter 2

Pre-Pregnancy Recommendations

• Complete imaging of the entire aorta using cardiac MRI or CT angiography is essential before pregnancy to fully assess the extent of aortic dilation 1, 2
• For patients with BAV planning pregnancy with an aortic root diameter of 4.5 cm, prophylactic aortic root surgery should be considered 1, 2
• The European Society of Cardiology recommends prophylactic aortic root surgery in women desiring pregnancy with aortic diameters >45 mm 1

Management Algorithm for BAV with 4.5 cm Aortic Root Planning Pregnancy:

1. Immediate pre-conception evaluation:

   • Complete imaging of the entire aorta (CT/MRI) to fully assess the extent of dilation 1
   • Evaluation by a multidisciplinary pregnancy heart and vessel team 1

2. Surgical consideration:

   • With aortic root diameter of 4.5 cm, prophylactic aortic root surgery should be considered before pregnancy 1
   • The decision for surgery should take into account:
     • Family history of aortic dissection
     • Growth rate (≥0.5 cm/year indicates higher risk) 1, 2
     • Body surface area (especially important in women of small stature) 1

3. If pregnancy is pursued without surgery:

   • Frequent echocardiographic monitoring (every 4-12 weeks) throughout pregnancy and 6 months postpartum 1
   • Treatment with beta-blockers throughout pregnancy to reduce risk of dissection 1
   • Delivery planning with consideration for caesarean section 2

Surgical Thresholds

• For patients with BAV not planning pregnancy, surgery for bicuspid aortopathy is recommended when the maximum aortic diameter is ≥50 mm 1
• For women planning pregnancy, a lower threshold (>45 mm) should be considered 1, 2
• In patients with low surgical risk, surgery for bicuspid aortopathy of ascending phenotype should be considered when the maximum aortic diameter is >52 mm 1

Important Caveats

• The risk of pregnancy in women with BAV and dilated aorta has not been systematically investigated 1
• Echocardiography alone may not adequately visualize the distal ascending aorta, which is often the site of maximal dilation in BAV patients 1, 3
• Even after aortic root replacement, patients remain at risk for dissection in the residual aorta and require continued surveillance 1
• Consideration of body surface area is important when evaluating aortic dimensions, especially in women of small stature 1

Long-term Follow-up

• If surgery is not performed, annual imaging with echocardiography or other imaging techniques is indicated once the ascending aorta reaches 40 mm 3
• More frequent imaging (every 6-12 months) is recommended if there are additional risk factors or if significant growth is detected 2, 4
• Lifelong beta-blocker therapy should be considered to reduce the rate of aortic dilation 1, 2