[Modeling of elastic deformation and vascular resistance of arterial and venous vasa vasorum].

血管 解剖 静脉曲张 医学 静脉 血管 静脉瓣膜 动脉壁 心脏病学 内科学 外科
作者
G. Maurice,X Wang,Bertrand Lehalle,J.F. Stoltz
出处
期刊:PubMed 卷期号:23 (4): 282-8 被引量:9
链接
标识
摘要

As in most living tissues, a network of nutritional vessels, the so-called vasa vasorum, irrigates the vessel wall under physiological conditions. An alteration or obstruction of this network can induce severe lesions. Most normal arteries and veins are irrigated by a vasa vasorum network located mainly in the adventice. They essentially supply oxygen to the outer layers of the vascular wall, the inner layer being mainly oxygenated by direct diffusion from bloodstream. Vasa vasorum responds to vasomotor stimuli and can even regress, e.g., after vascularization of arterial grafts. Their pathophysiological importance for arteries is now established. Indeed, it is known that an infusion disorder or vasa vasorum alteration may induce or promote early atherosclerotic lesions, fibrodysplasia or even media necrosis. From a mechanical point of view, and considering the three layers as a unique material, the vessel shows non-isotropic linear elastic and incompressible (v = 0.5) behaviour in the case of minimal or moderate deformation. But in the case of major deformation, the vessel displays a non-linear behaviour. The interaction between vasa vasorum supply and the mechanical properties of the arterial vascular wall can promote the occurrence of aneurysms as soon as vasa vasorum irrigation decreases. Some authors have hypothesized that these microvessels could fulfil the same function in the venous wall. It appears also that microcirculation flow rates are lower in varicose veins than in healthy ones and that partial oxygen pressure, already low in a healthy vein media, is even lower in a varicose vein. All these facts underline the importance of supply by the vasa vasorum network and its determining role in maintaining vascular wall integrity. In addition, the influence of vessel non-linear properties and their pathological changes on microcirculation would partially explain media necrosis in arteries and veins. Studying vascular wall deformation under the influence of intraluminal pressure revealed that an initially circular vasa vasorum rapidly takes on an elliptical shape which results more from crosswise circumferential stretching of the wall than from radial crushing. This induces increased hydraulic resistance. Thus permanent overpressure reduces vascular wall irrigation. Once the wall has been devascularized, it will loose its elasticity, harden and retain its maximal deformation. A vicious circle is then created. This phenomenon, noticeable in arteries, could be more serious in veins because their walls are thinner and elasticity modulus is lower. For example, for an intraluminal overpressure of 100 mmHg in an artery and 10 mmHg in a vein the ellipticity of the vasa vasorum becomes 1.2 and 3 respectively. Based on the hypothesis of a linear elastic behaviour and a periodical intraluminal overpressure, the ratio of the two axis of an arterial vasa vasorum B/A varies from 1.13 to 1.28 for Pa = 100 + 30 sin (2 pi t) mmHg, and from 1.24 to 1.44 for Pa = 160 + 40 sin (2 pi t) mmHg. In this case, the ratio of hydraulic resistances R(ellipse)/R(circle) changes little (less than 1, the ratio of the axis varies from 1.1 to 2.6 for Pa = 5 + 5 sin (2 pi t) mmHg) and from 1.8 to 5.8 for Pa = 10 + 5 sin (2 pi t) mmHg). Thus the ratio of hydraulic resistance varies from 1 to 1.5 and from 1.2 to 2.8 respectively. In practice Young's modulus increases in parallel with luminal pressure by limiting vascular wall and vasa vasorum deformation. If we consider the non-linear behaviour of the vessel wall and suppose the same conditions of intraluminal pressure, the ratio of the axis of the venous vasa vasorum in a hypertensive patient varies from 1.6 to 2.6 (instead of 1.8 to 5.8 in the case of linear model). This ratio is higher than that of the healthy subject which is less than 1.7. So the vascular structure in physiological conditions itself reacts to the pressure increases which may jeopardize vasa vasorum irrigation by delaying mural transfor

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
小丸子和zz完成签到 ,获得积分10
刚刚
量子星尘发布了新的文献求助10
1秒前
江雁完成签到,获得积分10
1秒前
坚定芯完成签到,获得积分10
1秒前
叶子兮完成签到,获得积分10
3秒前
幽默的妍完成签到 ,获得积分10
3秒前
Snow完成签到 ,获得积分10
3秒前
3秒前
liuyuh完成签到,获得积分10
4秒前
悠明夜月完成签到 ,获得积分10
5秒前
乌云乌云快走开完成签到,获得积分10
5秒前
你是我的唯一完成签到 ,获得积分10
5秒前
洁白的故人完成签到 ,获得积分10
7秒前
乐观半兰发布了新的文献求助10
7秒前
water应助科研通管家采纳,获得10
8秒前
zhang完成签到 ,获得积分10
8秒前
water应助科研通管家采纳,获得10
8秒前
Jasper应助科研通管家采纳,获得10
8秒前
科研通AI2S应助科研通管家采纳,获得10
8秒前
orixero应助科研通管家采纳,获得10
8秒前
CodeCraft应助科研通管家采纳,获得10
8秒前
大模型应助科研通管家采纳,获得10
8秒前
8秒前
鲲鹏完成签到 ,获得积分10
9秒前
大气建辉完成签到 ,获得积分10
9秒前
尛森完成签到,获得积分10
9秒前
机灵枕头完成签到 ,获得积分10
10秒前
糖糖科研顺利呀完成签到 ,获得积分10
12秒前
辣小扬完成签到 ,获得积分10
14秒前
传奇3应助水晶茶杯采纳,获得10
16秒前
幽默的素阴完成签到 ,获得积分10
20秒前
小小鱼完成签到 ,获得积分10
27秒前
27秒前
甜美砖家完成签到 ,获得积分10
29秒前
superspace完成签到,获得积分10
30秒前
nn发布了新的文献求助10
32秒前
求助完成签到,获得积分10
33秒前
34秒前
翁雁丝完成签到 ,获得积分10
41秒前
郭义敏完成签到,获得积分0
41秒前
高分求助中
【提示信息,请勿应助】关于scihub 10000
Les Mantodea de Guyane: Insecta, Polyneoptera [The Mantids of French Guiana] 3000
徐淮辽南地区新元古代叠层石及生物地层 3000
The Mother of All Tableaux: Order, Equivalence, and Geometry in the Large-scale Structure of Optimality Theory 3000
Handbook of Industrial Diamonds.Vol2 1100
Global Eyelash Assessment scale (GEA) 1000
Picture Books with Same-sex Parented Families: Unintentional Censorship 550
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 4038112
求助须知:如何正确求助?哪些是违规求助? 3575788
关于积分的说明 11373801
捐赠科研通 3305604
什么是DOI,文献DOI怎么找? 1819255
邀请新用户注册赠送积分活动 892655
科研通“疑难数据库(出版商)”最低求助积分说明 815022