Bicuspid Aortic Valves Are Associated With Aortic Dilatation Out of Proportion to Coexistent Valvular Lesions

Abstract

Background-Bicuspid aortic valves (BAVs) are associated with premature valve stenosis, regurgitation, and ascending aortic aneurysms. We compared aortic size in BAV patients with aortic size in control patients with matched valvular lesions (aortic regurgitation, aortic stenosis, or mixed lesions) to determine whether intrinsic aortic abnormalities in BAVs account for aortic dilatation beyond that caused by valvular hemodynamic derangement alone. Methods and Results-Diameters of the left ventricular outflow tract, sinus of Valsalva, sinotubular junction, and proximal aorta were measured from transthoracic echocardiograms in 118 consecutive BAV patients. Annular area was measured by planimetry, and BAV eccentricity was expressed as the ratio of the right leaflet area to the total annular area. Seventy-seven control patients with tricuspid aortic valves were matched for sex and for combined severity of regurgitation and stenosis. BAV patients (79 men and 39 women, aged 44.1Ϯ15.5 years) had varying degrees of regurgitation (84 patients [71%]) and stenosis (48 patients [41%]). Within the bicuspid group, multivariate analysis demonstrated that aortic diameters increased with worsening aortic regurgitation (PϽ0.001) and advancing age (PϽ0.05) but not with the severity of aortic stenosis. BAV patients had larger aortic diameters than did control patients at all ascending aortic levels measured (PϽ0.01), despite advanced age in the control patients. Conclusions-Aortic dimensions are larger in BAV patients than in control patients with comparable degrees of tricuspid aortic valve disease. Although more severe degrees of aortic regurgitation are associated with aortic dilatation in BAV patients, intrinsic pathology appears to be responsible for aortic enlargement beyond that predicted by hemodynamic factors. (Circulation. 2000;102[suppl III]:III-35-III-39.)

Clinical and Genetic Aspects of Bicuspid Aortic Valve: A Proposed Model for Family Screening Based on a Review of Literature

“…They observed comparable degrees of aortic regurgitation, stenosis or mixed lesions, and concluded that intrinsic pathology appears to be responsible for aortic enlargement. 21 These observations support the hypothesis that BAV and TAA are independent manifestations of a single gene defect in a subset of BAV families. 21,32,61 The risk of dilatation of the thoracic aorta might therefore be increased in some first-degree relatives of BAV patients, even in the absence of a bicuspid aortic valve.…”

“…21 These observations support the hypothesis that BAV and TAA are independent manifestations of a single gene defect in a subset of BAV families. 21,32,61 The risk of dilatation of the thoracic aorta might therefore be increased in some first-degree relatives of BAV patients, even in the absence of a bicuspid aortic valve. Vice versa, a limited number of studies suggest that BAV might be more prevalent in familial thoracic aneurysms and dissections (FTAAD) and in some hereditary connective tissue disorders associated with an increased risk of aortic aneurysms (for example Marfan syndrome).…”

“…16 Dilatation of the thoracic aorta, most commonly located in the ascending aorta, has been reported in 35-80% of adult BAV patients and has rarely been observed as early as childhood. [11][12][13][14][20][21][22][23][24][25] In adults TAA is defined as an aortic diameter with a z-score of ≥2, corresponding to an observed value >1.96 standard deviations above the predicted value for age, gender, and body surface area (BSA). 26 An aortic root >4.0 cm in adults is considered to be dilated irrespective of age, gender or BSA.…”

“…21,32,59,60 Martin et al performed bivariate genetic analyses between aortic dimensions and BAV. Their results did not support a shared underlying genetic basis for BAV and aortic measures.…”

Clinical, pathological, and molecular analyses of cardiovascular abnormalities in Costello syndrome: A Ras/MAPK pathway syndrome

“…A comparison between the outcome of Costello syndrome with MAT in young children and Noonan syndrome with multiple lentigines with older patients with conduction defects or ventricular arrhythmia associated with HCM is not meaningful (Table IV), but they represent the RASopathies currently with the most frequent and distinctive ''arrhythmia phenotypes.'' Mild aortic dilation in Costello syndrome was not related to bicuspid aortic valve [Keane et al, 2000] and may be a manifestation of an intrinsic vasculopathy. Prospective surveillance in the other RASopathies is needed to determine if aortic dilation, coronary artery dysplasia and hypertension (systemic and pulmonary) constitute a vasculopathy.…”