Bicuspid Aortic Valve (BAV)

Establish which lesion you actually have - BAV is a container for two opposite hemodynamic problems, so the valve phenotype drives the plan, not the diagnosis. Transthoracic echo gives peak and mean gradient for the stenotic valve, the degree of regurgitation for the incompetent one, and the diameter of the aortic sinuses and ascending aorta. Manage the hemodynamics per the dominant lesion — see the Aortic Stenosis and Aortic Regurgitation entries rather than treating “bicuspid valve” as a hemodynamic state of its own.

The aorta is the part that gets forgotten - Ascending dilation coexists independent of valve function. An ascending aorta at 4 cm goes under periodic echo surveillance, and over 4.5 cm the American Heart Association recommends annual echocardiography; CT or MR angiography measures it more accurately when echo windows are poor. About 30% of BAV patients coming for valve replacement need the sinuses or ascending aorta addressed at the same operation. A dilated root is why the pressor response to laryngoscopy matters here — see the Thoracic Aortic Aneurysm and Aortic Dissection entries.

What severe stenosis looks like on the ECG - Left ventricular hypertrophy with increased voltage in the lateral precordial leads and T-wave inversion in a strain pattern. Echo remains the study that quantifies the lesion; catheterization is reserved for when an intervention is planned.

Endocarditis risk is genuinely elevated - The risk of infective endocarditis is high in this population. Check the planned procedure against your institution's prophylaxis policy rather than assuming it does not apply.

Look for what travels with it - Between 50 and 75% of patients with coarctation of the aorta have a bicuspid valve, and BAV appears in about 30% of Turner syndrome and 30% of Williams syndrome, as well as with ventricular septal defect and Shone syndrome. Know the arch anatomy before you commit to an arterial line site or read anything into a single limb pressure.

The murmur and the click tell you where the valve is - The younger patient has an early ejection sound followed by a systolic ejection murmur. The click depends on cusp mobility, so it fades as the leaflets stiffen and is usually gone in severe aortic regurgitation. A well-functioning bicuspid valve may be entirely asymptomatic.

They come back younger - Valvuloplasty is the pediatric standard and recurrence of symptoms afterwards is common. Adults meet the same replacement indications as patients with a tricuspid valve but reach them considerably younger, which makes the mechanical-versus-bioprosthetic decision harder and means you will see them again for reoperation or for surgery carrying a prosthetic valve.

Family history is clinically useful - BAV occurs sporadically and in families, with 20 to 30% of family members and roughly 9 to 10% of first-degree relatives affected. First-degree relatives of a patient with aortopathy should be screened by echocardiography.

A bicuspid aortic valve (BAV) has two cusps instead of the usual three, most often from fusion of the right and left coronary cusps and usually unequal in size. At 1 to 2% of the population with a 2:1 male predominance it is the most common congenital cardiac lesion, and the one most likely to turn up in an adult room.

Whether the valve obstructs or leaks comes down to leaflet tissue: valves without redundant tissue degenerate into stenosis, while valves with redundant tissue become incompetent. Fusion of the right and left coronary cusps travels with coarctation of the aorta; fusion of the non-coronary and right coronary cusps travels with valvular stenosis and regurgitation. Degeneration over a lifetime is predictable and no medical therapy slows it. The second half of the disease is the aortopathy — the ascending aorta dilates independently of how the valve is working.