A bicuspid aortic valve (BAV) is the most prevalent congenital cardiac deformity, which is associated with an increased risk to develop a thoracic aortic aneurysm and/or an aortic dissection as... Show moreA bicuspid aortic valve (BAV) is the most prevalent congenital cardiac deformity, which is associated with an increased risk to develop a thoracic aortic aneurysm and/or an aortic dissection as compared to persons with a tricuspid aortic valve. Due to the high prevalence of a BAV in the general population and the associated life-long increased risk for adverse vascular events, BAV disease places a considerable burden on the public health. The aim of the present review is to discuss the role of transforming growth factor beta (TGF-ss) signaling in the development of the vascular wall and on how this complex signaling pathway may be involved in thoracic aortic aneurysm formation in tricuspid and BAV patients. Show less
Background: Thoracic aortopathy is a serious complication which is more often seen in patients with Marfan syndrome (MFS) and patients with a bicuspid aortic valve (BAV) than in individuals with a... Show moreBackground: Thoracic aortopathy is a serious complication which is more often seen in patients with Marfan syndrome (MFS) and patients with a bicuspid aortic valve (BAV) than in individuals with a tricuspid aortic valve (TAV). The identification of common pathological mechanisms leading to aortic complications in non-syndromic and syndromic diseases would significantly improve the field of personalized medicine. Objective: This study sought to compare thoracic aortopathy between MFS, BAV, and TAV individuals. Materials and methods: Bicuspid aortic valve (BAV; n = 36), TAV (n = 23), and MFS (n = 8) patients were included. Ascending aortic wall specimen were studied for general histologic features, apoptosis, markers of cardiovascular ageing, expression of synthetic and contractile vascular smooth muscle cells (VSMC), and fibrillin-1 expression. Results: The MFS group showed many similarities with the dilated BAV. Both patient groups showed a thinner intima (p < 0.0005), a lower expression of contractile VSMCs (p < 0.05), more elastic fiber thinning (p < 0.001), lack of inflammation (p < 0.001), and a decreased progerin expression (p < 0.05) as compared to the TAV. Other features of cardiovascular ageing differed between the BAV and MFS. Dilated BAV patients demonstrated less medial degeneration (p < 0.0001), VSMC nuclei loss (p < 0.0001), apoptosis of the vessel wall (p < 0.03), and elastic fiber fragmentation and disorganization (p < 0.001), as compared to the MFS and dilated TAV. Conclusion: This study showed important similarities in the pathogenesis of thoracic aortic aneurysms in BAV and MFS. These common mechanisms can be further investigated to personalize treatment strategies in non-syndromic and syndromic conditions. Show less
Background: Type A aortic dissections (TAAD) are devastating aortic complications. Patients with Marfan syndrome, a bicuspid aortic valve or a thoracic aortic aneurysm have an increased risk to... Show moreBackground: Type A aortic dissections (TAAD) are devastating aortic complications. Patients with Marfan syndrome, a bicuspid aortic valve or a thoracic aortic aneurysm have an increased risk to develop a TAAD. These predisposing conditions are characterized by a histologically thin intimal layer and hardly any atherosclerosis. Little is known about the susceptibility for atherosclerosis in patients with a type A aortic dissection. Objective: We aim to systematically describe atherosclerotic lesions in TAAD patients. Materials and methods: A total of 51 patients with a TAAD (mean age 62.5 +/- 10.8 years, 49% females) and 17 control patients (mean age 63 +/- 5.5 years, 53% females) were included in this study. Cardiovascular risk factors were assessed clinically. All sections were stained with Movat pentachrome and hematoxylin eosin. Plaque morphology was classified according to the modified AHA classification scheme proposed by Virmani et al. Results: In the TAAD group thirty-seven percent were overweight (BMI > 25). Diabetes and peripheral arterial disease were not present in any of the patients. Fifty-nine percent of the patients had a history of hypertension. The intima in TAAD patients was significantly thinner as compared to the control group (mean thickness 143 +/- 126.5 mu m versus 193 +/- 132 mu m, p < 0.023). Seven TAAD patients had a normal intima without any form of adaptive or pathological thickening. Twenty-three TAAD patients demonstrated adaptive intimal thickening. Fourteen had an intimal xanthoma, also known as fatty streaks. A minority of 7 TAAD patients had progressive atherosclerotic lesions, 4 of which demonstrated pathological intimal thickening, 3 patients showed early fibroatheroma, late fibroatheroma and thin cap fibroatheroma. In the control group the majority of the patients exhibited progressive atherosclerotic lesions: three pathologic intimal thickening, two early fibroatheroma, six late fibroatheroma, one healed rupture and two fibrotic calcified plaque. Discussion: This study shows that TAAD patients hardly exhibit any form of progressive atherosclerosis. The majority of TAAD patients showcase non-progressive intimal lesions, whereas the control group mostly demonstrated progressive intimal atherosclerotic lesions. Findings are independent of age, sex, or the presence of (a history of) hypertension. Show less
Background: A bicuspid aortic valve (BAV) is the most common congenital cardiac malformation. The development of the aortic valve is closely related to the development of the ascending aorta,... Show moreBackground: A bicuspid aortic valve (BAV) is the most common congenital cardiac malformation. The development of the aortic valve is closely related to the development of the ascending aorta, associated with structural differences in the bicuspid aorta. Here we describe the non-dilated ascending aortic wall in bicuspid aortic valve patients. Methods: BAV (n = 41) and tricuspid aortic valve (TAV) (n = 18) non-dilated ascending aortic wall samples were studied. We investigated the following features of the aortic wall: vessel wall thickness, endothelial cell morphology, atherosclerosis, and elastic lamellae organization. Medial pathologic features encompass-ing elastic fiber thinning, fragmentation and degeneration, overall medial degeneration, mucoid extracel-lular matrix accumulation, and smooth muscle cell nuclei loss were studied. Furthermore, we included apoptosis, periaortic inflammation, and the level of expression of differentiated vascular smooth muscle cells. Results: The non-dilated BAV ascending aortic wall is characterized by a significantly thinner intimal layer, without features of atherosclerosis ( P < .001). The medial layer is significantly thicker ( P < .001) with more mucoid extracellular matrix accumulation ( P < .001). All other medial pathologic features were more prominent in the TAV ( P < .001). The media has significantly less differentiated vascular smooth muscle cells ( P < .001) between the neatly regulated elastic lamellae which are thinner in the BAV as compared to the TAV ( P < .0 0 01). Conclusions: The BAV ascending aorta without dilatation is characterized by a differentiation def ect of vascular smooth muscle cells in the media and a significantly thinner intimal layer without overt patho-logic features.(c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ) Show less
A bicuspid aortic valve (BAV) is the most prevalent congenital cardiac anomaly, in which the valve has only two leaflets, instead of the normal three. Patients with a BAV have an increased risk of... Show moreA bicuspid aortic valve (BAV) is the most prevalent congenital cardiac anomaly, in which the valve has only two leaflets, instead of the normal three. Patients with a BAV have an increased risk of aneurysm formation and the development of an aortic dissection. Vascular smooth muscle cells in both the non-and dilated aortic wall are characterized by a maturation defect in all BAV patients, as compared to patients with a tricuspid aortic valve, which can contribute to inherent developmental susceptibility. Besides structural abnormalities of the vascular wall, a turbulent blood flow, caused by bicuspid valve geometry, could expedite the pathological process in the aortic wall, leading to aortopathy. Although the risk for aortopathy is significant, not all BAV patients experience (acute) aortic complications in their lifespan, highlighting the complexity of the pathogenetic process. Recent studies have focused on the embryonic development of semilunar valves and the ascending aortic wall. Their findings highlight that a defect in the embryogenesis could not only explain the development of a malformed aortic valve but also the increased risk for ascending aorta and arch pathology. This review presents an overview of the normal and abnormal development of the aortic valve and the aortic wall: a common defect in early embryogenesis causes the development of a BAV and associated aortopathy. Show less
Liang, W.; Menke, A.L.; Driessen, A.; Koek, G.H.; Lindeman, J.H.; Stoop, R.; ... ; Hoek, A.M. van den 2014