Management of Bicuspid Aortic Valve
Initial Diagnostic Workup
Obtain comprehensive transthoracic echocardiography at diagnosis to assess valve function and measure aortic dimensions at four critical levels: aortic annulus, sinuses of Valsalva, sinotubular junction, and mid-ascending aorta 1. Document the cusp fusion pattern, as fusion involving the noncoronary cusp carries significantly higher risk of aortic dilation (68% versus 40%) 1. Perform Doppler interrogation of the proximal descending aorta to exclude associated aortic coarctation 1. Quantify stenosis severity using standard gradients and valve area, or regurgitation severity using standard parameters 1.
When echocardiography cannot adequately visualize the ascending aorta beyond 4.0 cm from the valve plane, obtain cardiac MRI or CT angiography 1. Prioritize MRI over CT to avoid cumulative radiation exposure in patients requiring lifelong surveillance 1.
Family Screening
Screen all first-degree relatives with echocardiography, as 20-30% will have bicuspid valve disease or associated aortopathy 1. This is particularly critical if the patient has aortopathy or family history of valvular heart disease or aortopathy 1.
Surveillance Protocol
The surveillance interval depends on aortic diameter and rate of progression:
- For aortic dimensions 4.0-4.5 cm: Perform serial imaging (echocardiography, MRI, or CT) at intervals determined by rate of progression and family history 2, 1
- For aortic dimensions >4.5 cm: Perform annual imaging with echocardiography, MRI, or CT angiography 2, 1
Expected progression rates are 0.5 mm/year at sinuses and sinotubular junction, and 0.9 mm/year at proximal ascending aorta, though rates up to 2 mm/year have been reported 1. Adjust surveillance frequency accordingly if rapid progression is observed.
Medical Management
No proven medical therapies exist to reduce progression of bicuspid aortic valve-associated aortopathy 2, 1, 3. However, control hypertension with any effective antihypertensive agent 2, 1. Beta-blockers and ARBs have theoretical advantages but lack proven benefit in clinical studies for slowing aortic dilation 2, 1, 3.
Surgical Indications for Isolated Aortopathy
Operate when aortic diameter exceeds 5.5 cm at any level (sinuses, sinotubular junction, or ascending aorta) 1, 4.
Lower the surgical threshold to 5.0 cm when any of the following risk factors are present 1, 4:
- Family history of aortic dissection
- Rapid progression ≥0.5 cm/year
- Aortic coarctation
- Resistant hypertension
- Age <50 years
- Desire for pregnancy
The absolute risk of dissection remains low (3.1 per 10,000 patient-years), though 8.4 times higher than age-matched controls 1.
Surgical Indications for Valve Dysfunction
Operate on patients with symptomatic severe aortic stenosis or regurgitation (exertional dyspnea, angina, dizziness, or syncope) 3. Consider valve replacement when left ventricular ejection fraction declines or significant LV diameter changes approach intervention thresholds 3. Replace the valve when undergoing concurrent cardiac surgery (CABG or mitral valve surgery), even with moderate aortic valve dysfunction 3.
Combined Aortic and Valve Surgery
Replace the ascending aorta when its diameter exceeds 4.5 cm in patients undergoing aortic valve replacement for severe stenosis or regurgitation 1, 3, 4. This lower threshold (4.5 cm versus 5.5 cm for isolated aortopathy) reflects the opportunity to address both pathologies simultaneously without additional operative risk.
Valve-sparing operations yield excellent results in patients without severely deformed or dysfunctional valves 4.
Critical Pitfalls to Avoid
Do not rely solely on echocardiography if the ascending aorta cannot be visualized adequately—obtain MRI or CT 1. The mid-ascending aorta is frequently missed on transthoracic echocardiography, and this is a common site of dilation in bicuspid aortic valve patients.
Document the cusp fusion pattern—patients with noncoronary cusp involvement have higher risk of extensive aortic dilation extending to the transverse arch 1. This affects surgical planning and surveillance strategy.
Do not delay family screening—20-30% of first-degree relatives are affected 1. Early detection allows for appropriate surveillance before complications develop.
Always perform Doppler interrogation of the descending aorta to evaluate for aortic coarctation 1. This associated anomaly occurs frequently with bicuspid aortic valve and affects management decisions.