Bicuspid aortic valve disease and ascending aortic aneurysms: gaps in knowledge

Abstract

The bicuspid aortic valve is the most common congenital cardiac anomaly in developed nations. The abnormal bicuspid morphology of the aortic valve results in valvular dysfunction and subsequent hemodynamic derangements. However, the clinical presentation of bicuspid aortic valve disease remains quite heterogeneous with patients presenting from infancy to late adulthood with variable degrees of valvular stenosis and insufficiency and associated abnormalities including aortic coarctation, hypoplastic left heart structures, and ascending aortic dilatation. Emerging evidence suggests that the heterogeneous presentation of bicuspid aortic valve phenotypes may be a more complex matter related to congenital, genetic, and/or connective tissue abnormalities. Optimal management of patients with BAV disease and associated ascending aortic aneurysms often requires a thoughtful approach, carefully assessing various risk factors of the aortic valve and the aorta and discerning individual indications for ongoing surveillance, medical management, and operative intervention. We review current concepts of anatomic classification, pathophysiology, natural history, and clinical management of bicuspid aortic valve disease with associated ascending aortic aneurysms.

Figure 1

Photograph of surgically excised bicuspid aortic valve, demonstrating severe calcific stenosis. The left (L) and right (R) cusps are fused with a prominent calcified raphe, opposed to a calcified noncoronary cusp (N).

Figure 2

Computed tomography of a patient with a bicuspid aortic valve and aneurysmal dilatation of the aortic root, ascending aorta, and transverse aortic arch (Stanford cluster IV).

Figure 3

(a) Transesophageal echocardiogram demonstrating a bicuspid aortic valve in short-axis view, with left-right coronary cuspal fusion (Sievers' classification type 1, L-R, insufficient), and moderate-severe aortic insufficiency on colour flow Doppler (not shown). (b) Transesophageal echocardiogram demonstrating a dilated aortic root and ascending aorta in long-axis view along with a bicuspid aortic valve.

Figure 4

Intraoperative photograph demonstrating the dilated aortic root, ascending aorta, and proximal aortic arch (Stanford cluster IV), measuring 68 mm in the largest dimension on preoperative computed tomography (not shown).

Figure 5

(a) Intraoperative photograph demonstrating the aortic resection from the aortic valve to the aortic arch, utilizing the Peninsula technique. (b) Intraoperative photograph demonstrating the reconstructed aortic root, ascending aorta, and aortic arch.

Figure 6

(a) Intraoperative photograph demonstrating the bicuspid aortic valve in situ with the raphe between the left- and right-coronary cusps. (b) Intraoperative photograph demonstrating the results of the valve sparing aortic root replacement using the reimplantation technique. The free margin of the conjoined cusp was plicated and the free margin of the nonconjoined cusp underwent a triangular resection.

Figure 7

Postoperative transesophageal echocardiogram demonstrating good coaptation of the repaired aortic valve (a), without any residual aortic insufficiency on colour flow Doppler (b).