Rate of Stenotic Bicuspid Aortic Valve Aortic Dilatation After Aortic Valve Replacement, Calculated Using a 3-Dimensional Reconstruction Tool

Abstract

0.18±0.08 mm/m 2 after AVR. 9 The annual progression rate of BAV aortas, however, remains controversial, because the diameter of asymmetric dilated aorta is difficult to measure accurately on conventional computed tomography (CT). We postulated that the progression of ascending aortic diameter in BAV patients depends on its direction, because the dilated ascending aorta with BAV is expected to progress more rapidly toward the right-anterior quadrant, where WSS should be greater. 8 The aim of the present study was therefore to measure aortic diameter in the right-anterolateral direction in order to calculate an accurate progression rate of the asymmetric dilated ascending aorta after AVR. Aortic diameter was measured using 3-dimensional (3-D) reconstruction and an automated analysis tool, Mimics (Materialise, Leuven, Belgium), and the annual progression rate was compared between BAV and tricuspid aortic valve (TAV) patients. Methods Patient SelectionData derived from 28 patients (male, n=18; 64%; female, B icuspid aortic valve (BAV) is a common congenital heart malformation that occurs in 0.5-2% of the population. 1,2 Patients with BAV are at increased risk of developing serious aortic complications, including aortic dilatation, dissection and rupture after reaching adulthood. 2-4 The valve-related aortic complications, called BAV-related aortopathy, occur in 10-35%, and aortic dissection occurs in approximately 4% of patients with BAV. 3 Patients with BAV and dilated aorta have a 9-fold increased risk of aortic dissection. 5 On histology, aortas with BAV frequently show cystic medial degeneration, a characteristic histopathological defect of the aortic media. 3,5Ascending aortic dilatation associated with BAV frequently has an asymmetric configuration that bulges toward the right-anterior aspect of the aorta. 6 The asymmetric enlargement might be caused by valve-related hemodynamic abnormalities, which lead to the asymmetric distribution of wall shear stress (WSS). 7, 8 Yasuda et al reported that ascending aortic dilatation associated with BAV sometimes progresses even after aortic valve replacement (AVR). 9 They reported that the ascending aortic diameter increased at an annual rate of Background: Progression of asymmetric dilated aorta associated with bicuspid aortic valve (BAV) is difficult to evaluate conventionally. The aim of the study was to calculate the rate of progression of the dilated BAV aorta after aortic valve replacement (AVR) using a 3-dimensional (3-D) reconstruction tool.

Bicuspid aortic valve morphology and aortic valvular outflow jets: an experimental analysis using an MRI-compatible pulsatile flow circulation system

“…The natural history of aortopathy in BAV is quite different from that in tricuspid aortic valve (TAV). Progression of aneurysmal diameter is significantly faster with BAV than with TAV, even after aortic valve replacement 5,6 , possibly due to underlying intrinsic medial fragility combined with long-term exposure to BAV-related hemodynamic alterations. Therefore, the current guidelines on aortic diseases generally recommend early surgical intervention in a significantly dilated ascending aorta with BAV-defined as maximum diameter > 45 mm-to prevent sudden death from aortic dissection or rupture [7][8][9] .…”

Surgical treatment of mild to moderately dilated ascending aorta in bicuspid aortic valve aortopathy: the art of safety and simplicity

“…Bicuspid aortic valve (BAV) is a congenital variant of the aortic valve morphology whereby there is only two equal or unequal leaflets or cusps aortic valve with a single line of coaptation instead of three [12]. The bicuspid aortic valve is a common congenital cardiovascular malformation affecting 0.5 to 2% of the population [10]. BAV accounts for about 50% of adult cases of aortic stenosis and 70-85% of young adults subjects requiring surgical treatment and frequently aortic regurgitation requiring aortic replacement (AVR) where males are more victims in the ratio of 2:1 [15,16].…”

“…The folding and creasing of the valves and the turbulent flow contribute to the development of fibrosis and calcification. The combination of these processes results in accelerated disease progression [10].…”

“…Only replacement of dysfunctional aortic valve in patients with BAV may not be able to prevent progressive aortic dilation [9]. Modification to a reparative technique which includes replacing the aortic valve, decreasing the aortic diameter by excision of an oval segment, placing a well-tailored Dacron vascular graft around the ascending aorta, and anchoring it with previously placed sutures driven through the sewing ring of the valve prosthesis through the aortic wall, could done by a simple extravascular wrapping of the ascending aorta with a vascular graft may far useful particularly in geriatric subjects or individuals with high radical operative risks [10,11]. This prophylactic or corrective technique for mild-to-moderately dilated ascending aorta may be an option, is more responsible on the part of the surgeon than a "wait-and-watch" approach [12].…”

Re: “Bicuspid Aortic Valve Associated Aortopathy: A Primer for Cardiac Anaesthesiologists”

“…50 Pathophysiology BAV Aortopathy The pathophysiologic and histologic features of BAV-associated aortic dilatation are cystic medial necrosis, abnormal processing of the extracellular matrix protein by vascular smooth muscle cells, increased release of matrix metalloproteinases, increased apoptosis of vascular smooth muscle cells, and a medial layer abnormality likely from disrupted collagen and elastin. 51,52 The debate regarding BAV aortopathy heterogeneity encompasses both genetic and hemodynamic theories, though data pertaining to individual aortic phenotypes remains scarce. 53 "Genetic theory" states that an inherent aortic wall weakness results from a developmental abnormality of both the aortic valve and the aortic wall.…”