What are the screening and management recommendations for individuals with a family history of bicuspid aortic valve (BAV)?

Screening and Management Recommendations for Individuals with a Family History of Bicuspid Aortic Valve (BAV)

First-degree relatives of patients with bicuspid aortic valve should undergo echocardiographic screening to identify undiagnosed BAV and associated aortopathy, as this screening has been shown to be both clinically important and cost-effective. 1, 2

Prevalence and Inheritance Pattern

• BAV is the most common congenital heart defect, affecting 0.5-2% of the general population with a 3:1 male-to-female predominance 1
• Familial clustering is significant:
  • 20-30% of patients with BAV have affected family members 1
  • Studies show 8-9% prevalence of BAV among first-degree relatives 3, 4, 5
  • Inheritance pattern is compatible with autosomal dominant transmission with reduced penetrance 4

Screening Recommendations for Family Members

Who Should Be Screened

• All first-degree relatives (parents, siblings, children) of patients with BAV 1
• This recommendation is supported by both ACC/AHA guidelines and cost-effectiveness analyses 1, 2

Screening Method and Timing

• Initial screening:

  • Transthoracic echocardiography (TTE) is the primary screening tool 1
  • Should include assessment of both valve morphology and aortic dimensions 1
  • Screening should be performed regardless of age 5, 2

• If TTE is inadequate:

  • CMR (cardiac magnetic resonance) or CT angiography should be used 1

Management of Individuals Found to Have BAV

Surveillance Imaging for BAV Patients

1. For BAV patients with normal aortic dimensions (<4.0 cm):

   • TTE every 3-5 years 1

2. For BAV patients with aortic dilation (≥4.0 cm):

   • Lifelong serial evaluation with TTE, CMR, or CT angiography is recommended 1
   • Imaging frequency based on aortic diameter:
     • 4.0-4.9 cm: Every 12 months 6
     • 5.0-5.5 cm: Every 6 months 6
     • ≥5.5 cm: Consider surgical intervention 6

3. For BAV patients with risk factors for dissection:

   • More frequent monitoring (every 6-12 months) if:
     • Growth rate ≥0.5 cm per year
     • Family history of aortic dissection
     • Presence of aortic coarctation
     • Uncontrolled hypertension 6

Medical Management

• Optimal blood pressure control targeting <140/90 mmHg 6
• Beta-blockers are preferred first-line agents for blood pressure control 6
• Moderate aerobic exercise is generally safe, but patients should avoid:
  • Strenuous isometric exercise
  • Contact sports
  • Competitive sports (especially with borderline aortic diameters) 6

Surgical Intervention Thresholds

• General population with BAV: ≥5.5 cm 6
• BAV patients: ≥5.0 cm 1, 6
• BAV patients undergoing aortic valve surgery: ≥4.5 cm 1, 6
• Consider earlier intervention with:
  • Rapid growth (≥3 mm/year)
  • Family history of aortic dissection
  • Development of significant aortic regurgitation 6

Post-Surgical Management

• Lifelong surveillance imaging is essential after surgical intervention:
  • Annual imaging for aortic diameter >4.0 cm
  • Imaging every 2-3 years for aortic diameter <4.0 cm 6
• Use consistent imaging modality for accurate comparison between studies 6

Implementation Challenges and Practical Considerations

• Studies show variable implementation rates (67-90%) of family screening 3, 5
• Key challenges include:
  • Patient education about inheritance patterns
  • Coordination of family member screening
  • Ensuring follow-up compliance 3
• Cost-effectiveness analyses show screening is not only clinically important but also cost-saving (€644 savings and 0.3 QALY gains per screened individual) 2

Pitfalls to Avoid

• Failing to inform BAV patients about familial risk (20-30% of patients have affected family members)
• Using inconsistent imaging techniques or measurement locations during follow-up
• Neglecting to screen all first-degree relatives, regardless of age
• Overlooking associated conditions like aortic coarctation
• Discontinuing surveillance after negative initial screening (progression can occur over time)
• Failing to adjust surgical thresholds based on individual risk factors