Durić Dragan, Jakovljević Vladimir, Stojković Mirjana, Durić Andelka, Petrović Branko
Med Pregl. 2003;56 Suppl 1:9-12.
AGING AS A CARDIOVASCULAR RISK FACTOR: Atherosclerosis is the major cause of mortality in the Western world (>50%) as well as in Serbia and Montenegro (>60%). Atherosclerosis/arteriosclerosis functional and structural vascular changes as a consequence of angina pectoris, myocardial infarction, transient ischemic cerebrovascular attacks, stroke, ischaemic attacks in peripheral circulation and/or thromboembolic complications. Aging, lipids (oxidized LDL), infective agents, inflammation, increased glucose level, hypertension, smoking, increased homocysteine level, oxidative stress etc. are recognized as factors which lead to endothelial dysfunction and cause atherosclerosis. Thus, in response to such attacks endothelium releases different substances like: nitric oxide, prostacyclin, endothelium-derived hyperpolarizing factor (EDHF), endothelin, bradykinin, angiotensin II, free oxygen radicals etc. which could be involved in the pathogenesis of atherosclerosis. Atherosclerosis/arteriosclerosis begins with endothelial vasomotor and anti-thrombotic dysfunction and it is of strategic importance to discover this condition earlier. In regard aging, both higher thickness and stiffness of arterial blood vessels appear following an incidence of cardiovascular diseases.
Over the last decade non-invasive, echosonographic method for visualization of carotid intima-media thickness (indicator of arteriosclerosis/atherosclerosis) was introduced in clinical practice. However, it is also used to compare brachial artery diameter changes, linear velocity and bloodflow which are estimated during basal conditions, during ischemia, during reactive hyperemia (endothelium/independent phase) as well as with left ventricular mass index.
Due to aging there is a decreased response to reactive hyperemia, increased carotid intima-media thickness and increased left ventricular mass, but there is a lack of time-dependent correlation. First endothelial dysfunction occur twenty years before any manifestations appear--as typical vascular and ventricular remodeling. During this period certain markers, for example homocysteine, and diagnostic procedures are important parts of primary prevention.
衰老作为一种心血管危险因素:动脉粥样硬化是西方世界(>50%)以及塞尔维亚和黑山(>60%)主要的死亡原因。动脉粥样硬化/动脉硬化是心绞痛、心肌梗死、短暂性缺血性脑血管发作、中风、外周循环缺血发作和/或血栓栓塞并发症导致的功能性和结构性血管变化。衰老、脂质(氧化型低密度脂蛋白)、感染因子、炎症、血糖水平升高、高血压、吸烟、同型半胱氨酸水平升高、氧化应激等被认为是导致内皮功能障碍并引发动脉粥样硬化的因素。因此,作为对这些攻击的反应,内皮会释放不同的物质,如一氧化氮、前列环素、内皮衍生超极化因子(EDHF)、内皮素、缓激肽、血管紧张素II、游离氧自由基等,这些物质可能参与动脉粥样硬化的发病机制。动脉粥样硬化/动脉硬化始于内皮血管舒缩和抗血栓功能障碍,更早发现这种情况具有战略重要性。就衰老而言,心血管疾病发生后,动脉血管的厚度和硬度都会增加。
在过去十年中,用于可视化颈动脉内膜中层厚度(动脉硬化/动脉粥样硬化指标)的非侵入性超声检查方法被引入临床实践。然而,它也用于比较肱动脉直径变化、线性速度和血流,这些指标在基础状态、缺血期间、反应性充血(内皮/非依赖性阶段)以及与左心室质量指数期间进行评估。
由于衰老,对反应性充血的反应降低,颈动脉内膜中层厚度增加,左心室质量增加,但缺乏时间依赖性相关性。最早的内皮功能障碍在任何表现出现前二十年就已发生——作为典型的血管和心室重塑。在此期间,某些标志物,例如同型半胱氨酸,以及诊断程序是一级预防的重要组成部分。