Molecular evaluation of the great vessels of patients with bicuspid aortic valve disease

Abstract

Abstract:Purpose: Bicuspid aortic valve (BAV) is associated with increased prevalence of annulo-aortic ectasia, dissection and ascending aortic aneurysm. This study was undertaken to compare the amount of fibrillin-1 and elastin in the media of great vessels of patients with bicuspid and tricuspid aortic valve disease. Method: Tissue samples of ascending aorta and pulmonary artery were obtained from 22 patients with bicuspid aortic valve disease (BAV) and 17 patients with tricuspid aortic valve disease (TAV), including 6 normal valves from the transplant program. Indirect immunofluorescence and computerized image analyses were used to quantify fibrillin-1 and elastin of the media of the arteries. The results were expressed as the mean integrated optical density (IOD). Results: In the ascending aorta, the IOD for fibrillin-1 was 15 ± 8 in the BAV group and 24 ± 7 in the TAV group (p = 0.001). In the pulmonary artery, the IOD for fibrillin-1 was 18 ± 10 in the BAV group and 25 ± 9 in the TAV group (p = 0.07). In respect to the elastin measurements of the aorta, the specific IOD was 34 ± 13 in the BAV group and 29 ± 14 in the TAV group. In the pulmonary artery the IOD for elastin was 30 ± 12 in the BAV group and 29 ± 14 in the TAV group (p = 0.34). Conclusions: Patients with BAV were found to have less fibrillin-1 in the ascending aorta and pulmonary artery than patients with TAV. These findings may explain aortic root dilation and ascending aortic dissection in patients with BAV disease.Descriptors: Aortic valve, pathology. Aorta, aneurysm, dissection, surgery. Fibrillin. Elastin. Marfan syndrome. ResumoObjetivo: A valva aórtica bicúspide (VAB) está associada a maior prevalência de ectasia anulo-aórtica, aneurisma e dissecção da aorta ascendente. Este estudo investigou a quantidade de fibrilina-1 e elastina nos grandes vasos de portadores de VAB.Método: Amostras de tecidos foram colhidas da aorta ascendente e tronco da artéria pulmonar de 22 portadores de VAB e 16 portadores de valva aórtica tricúspide (VAT) submetidos a cirurgia cardíaca, incluindo seis portadores de valva aórtica normal, provenientes do programa de transplante. Imunofluorescência indireta e análise computadorizada de imagens foram utilizadas para Rev Bras Cir Cardiovasc 2003; 18(2): 148-156

Enlightening the Association between Bicuspid Aortic Valve and Aortopathy

“…A deficiency of fibrillin has been associated with BAV disease [ 53 ]. Studies comparing BAV and TAV AAo specimens identified a decrease in fibrillin-1 in BAV patients, which may contribute to explaining aortic root dilation and AAo dissection in these patients [ 54 , 55 ]. In two studies of BAV, TAV, and Marfan patients, both Marfan and BAV showed a differential distribution and decreased fibrillin-1 expression in the aorta, as well as significant decrease in differentiated SMC markers, suggesting a maturation defect of the aortic wall [ 38 , 39 , 56 ].…”

The Bicuspid Aortic Valve

“…It has been noted that the fibrillin-1 content was remarkably reduced in the aorta of BAV patients, compared with that of patients with a tricuspid aortic valve. Aortic elasticity measurements of BAV patients suggest that diminished aortic elasticity is at least part of its causation [23][24][25].…”