Rizzoni Damiano, Agabiti-Rosei Claudia, Boari Gianluca E M, Muiesan Maria Lorenza, De Ciuceis Carolina
Department of Clinical and Experimental Sciences, University of Brescia, 25121 Brescia, Italy.
Second Division of Medicine, Spedali Civili di Brescia, 25123 Brescia, Italy.
J Clin Med. 2023 Jul 25;12(15):4892. doi: 10.3390/jcm12154892.
Arterial hypertension is a common condition worldwide and an important risk factor for cardio- and cerebrovascular events, renal diseases, as well as microvascular eye diseases. Established hypertension leads to the chronic vasoconstriction of small arteries as well as to a decreased lumen diameter and the thickening of the arterial media or wall with a consequent increased media-to-lumen ratio (MLR) or wall-to-lumen ratio (WLR). This process, defined as vascular remodeling, was firstly demonstrated in small resistance arteries isolated from subcutaneous biopsies and measured by micromyography, and this is still considered the gold-standard method for the assessment of structural alterations in small resistance arteries; however, microvascular remodeling seems to represent a generalized phenomenon. An increased MLR may impair the organ flow reserve, playing a crucial role in the maintenance and, probably, also in the progressive worsening of hypertensive disease, as well as in the development of hypertension-mediated organ damage and related cardiovascular events, thus possessing a relevant prognostic relevance. New non-invasive techniques, such as scanning laser Doppler flowmetry or adaptive optics, are presently under development, focusing mainly on the evaluation of WLR in retinal arterioles; recently, also retinal microvascular WLR was demonstrated to have a prognostic impact in terms of cardio- and cerebrovascular events. A rarefaction of the capillary network has also been reported in hypertension, which may contribute to flow reduction in and impairment of oxygen delivery to different tissues. These microvascular alterations seem to represent an early step in hypertension-mediated organ damage since they might contribute to microvascular angina, stroke, and renal dysfunction. In addition, they can be markers useful in monitoring the beneficial effects of antihypertensive treatment. Additionally, conductance arteries may be affected by a remodeling process in hypertension, and an interrelationship is present in the structural changes in small and large conductance arteries. The review addresses the possible relations between structural microvascular alterations and hypertension-mediated organ damage, and their potential improvement with antihypertensive treatment.
动脉高血压是一种全球常见的病症，是心脑血管事件、肾脏疾病以及微血管眼部疾病的重要危险因素。确诊的高血压会导致小动脉慢性血管收缩，管腔直径减小，动脉中膜或血管壁增厚，从而使中膜与管腔比值（MLR）或壁腔比值（WLR）增加。这一过程被定义为血管重塑，最初是在从皮下活检分离出的小阻力动脉中得到证实，并通过微血管造影术进行测量，目前这仍被视为评估小阻力动脉结构改变的金标准方法；然而，微血管重塑似乎是一种普遍现象。MLR升高可能会损害器官血流储备，在高血压疾病的维持以及可能的病情逐渐恶化过程中，以及在高血压介导的器官损伤和相关心血管事件的发生中发挥关键作用，因此具有重要的预后意义。目前正在研发新的非侵入性技术，如扫描激光多普勒血流仪或自适应光学技术，主要聚焦于评估视网膜小动脉的WLR；最近，视网膜微血管WLR在心血管和脑血管事件方面也被证明具有预后影响。高血压患者还存在毛细血管网稀疏的情况，这可能导致不同组织的血流减少和氧输送受损。这些微血管改变似乎是高血压介导的器官损伤的早期阶段，因为它们可能导致微血管性心绞痛、中风和肾功能不全。此外，它们可作为监测降压治疗有益效果的有用标志物。此外，传导动脉在高血压中可能会受到重塑过程的影响，小传导动脉和大传导动脉的结构变化之间存在相互关系。本文综述探讨了微血管结构改变与高血压介导的器官损伤之间的可能关系，以及降压治疗对其潜在的改善作用。
