Abstract
Background: Bicuspid aortic valve (BAV) is associated with both aortic valve stenosis and aortic disease such as true aneurysm or Stanford type A dissection. Currently the indications for concomitant surgery for the ascending aorta among patients with aortic valve stenosis are decided based on the diameter of the aorta at the time of surgery. Recently the ratio of aortic curvature has been reported to be an important predictor of future aortic events. In this paper, we evaluated the relationship between the valve phenotype and the ratio of aortic curvature among patients who underwent surgery for aortic valve stenosis.
Methods: Out of a total of 142 patients who received aortic valve surgery, 117 patients who were evaluated using two-dimensional computed tomography (2D-CT) or echocardiography were analyzed retrospectively. The patients were divided into BAV and tricuspid aortic valve (TAV) groups. The ratio of the curvature was calculated using axially-resolved methods (X-axis, Y-axis and square root of X2 and Y2;√X2+Y2).
Results: Forty-two patients had BAV and 75 had TAV. The X-axis component was significantly greater in the BAV group (18.8 ± 5.1 mm vs 12.3 ± 4.6 mm for BAV vs TAV, respectively [p<0.0001]), although the Y-axis component was not significantly different. A subanalysis of BAV types (R-L type: right and non coronary cusps fusion or A-P type: right and left coronary cusps fusion) demonstrated that the Y-axis component was significantly greater for the A-P type than for the R-L type, although the X-axis components were not different.
Conclusions: Patients with BAV, especially the A-P type, exhibit a greater alteration in the ratio of aortic curvature. The morphological displacement is an additional important factor that concerns the surgical strategy for the ascending aorta in BAV patients with aortic stenosis.
