肾素-血管紧张素-醛固酮系统阻断剂对心房颤动患者心房解剖及电重构的影响

<正> 心房颤动(房颤)是临床最常见的心律失常,发病率呈增高趋势,可导致脑卒中和心力衰竭。随着房颤发作的持续,心房电生理特征和结构发生一系列改变即心房电重构和结构重构,心房重构是房颤发生和维持的主要机制。肾素-血管紧张素-醛固酮系统(renin-angiotensin-aldosterone system,RAAS)在调节心血管活动中起重要作用,参与许多病理生理过程。近几年的研究显示RAAS参与房颤心房的解剖及电     

肾素-血管紧张素-醛固酮系统抑制与心房颤动

心房颤动(房颤)是临床最常见的心律失常之一,大多数房颤复律后容易反复发作,部分转为永久性房颤。积极地控制房颤,不仅在于消除患者心悸等不适症状,而且对防止血栓栓塞等并发症的发生有重要意义。近年来,大量研究显示通过抑制肾素-血管紧张素-醛固酮系统可对房颤有一定的预防作用。因此,应用血管紧张素转换酶抑制剂和血管紧张素受体阻断剂抑制肾素-血管紧张素-醛固酮系统预防房颤,可望成为控制房颤的一条新途径。     

肾素-血管紧张素系统与心房颤动

心房颤动(AF)是一常见的心血管疾病,心房重构是AF维持和复发的主要机制,肾素-血管紧张素-醛固酮系统(RAAS)在心房重构中起重要作用。作用于RAAS的一些药物具有抑制心房重构的作用并减少AF的发作,给AF的治疗提供了一个新的思路。本文对RAAS在心房重构中的作用,及其拮抗剂对心房重构及AF的影响作一综述。     

肾素-血管紧张素系统与心房颤动

心房颤动(AF)是一常见的心血管疾病,心房重构是AF维持和复发的主要机制,肾素-血管紧张素-醛固酮系统(RAAS)在心房重构中起重要作用.作用于RAAS的一些药物具有抑制心房重构的作用并减少AF的发作,给AF的治疗提供了一个新的思路.本文对RAAS在心房重构中的作用,及其拮抗剂对心房重构及AF的影响作一综述.     

肾素-血管紧张素系统阻断剂与心房颤动

心房颤动是临床最常见的心律失常之一,发病率呈增加趋势。心房电重构和结构重构是心房颤动维持和复发的主要机制,肾素-血管紧张素系统在心房重构中起重要作用。肾素-血管紧张素系统阻断剂（血管紧张素转化酶抑制剂和血管紧张素受体阻断剂）通过抑制心房不应期缩短和抗心房结构重构等作用抑制心房重构并减少心房颤动的发作。肾素-血管紧张素系统阻断剂影响心房结构和功能,为心房颤动的防治提供了一种新的选择。     

肾素-血管紧张素系统与心房颤动关系的研究进展

心房颤动是最常见的心律失常。近年来,心房重构现象被认为可能是心房颤动发生和维持的机制,而心房纤维化可能是心房重构中最为关键的过程,肾素-血管紧张素系统研究证实有起介导心房纤维化进程的作用,现就肾素-血管紧张素系统在心房颤动发生和发展中的作用机制作一综述。     

肾素血管紧张素系统和心房颤动

肾素 血管紧张素系统 (RAS)是机体重要的神经内分泌系统之一 ,对机体血压和体液、电解质平衡起重要调节作用。近年来的研究表明 ,RAS和心房颤动有关。在房颤动物模型和房颤患者都发现了RAS激活证据 ,RAS激活后通过多种机制影响心房结构和电生理特性 ,从而影响房颤的发生和维持 ,采取不同措施干预RAS已取得了有益作用 ,本文将对上述内容做一综述。     

心房颤动患者脑钠素的变化及其与肾素血管紧张素醛固酮系统的关系

目的:探讨持续性心房颤动患者的血脑钠素(BNP)水平的改变及其与肾素血管紧张素醛固酮系统的关系.方法:对108例符合入选标准的住院患者分为持续性心房颤动组(55例)和对照组(53例),对2组患者的血BNP、肾素、血管紧张素Ⅱ、醛固酮水平进行检测,并行经胸超声心动图检查,测量左心房前后径.结果:2组血BNP分别为(79.65±16.23)/μg/L、(50.12±15.97)μg/L(均P＜0.01),多元线性逐步回归分析表明:左房内径、血管紧张素Ⅱ浓度是高血BNP水平的独立预测因素.结论:持续性心房颤动患者血BNP水平明显升高,与心房颤动患者的结构重构及肾素血管紧张素醛固酮系统密切相关.     

作用于肾素-血管紧张素-醛固酮系统的心力衰竭治疗新策略

心力衰竭（HF）是各种心血管病的严重和终末阶段,其患病率高、死亡率高、再住院率高,给公众带来了沉重的疾病负担。神经内分泌系统尤其是肾素-血管紧张素-醛固酮系统（renin-angiotensin-aldosterone system,RAAS）的过度激活在HF病理发展过程中起着关键作用,RAAS抑制剂（ACEIs/ARBs、醛固酮受体拮抗剂）已是HF治疗的基石。近年HF治疗取得令人瞩目的成就。PARDIGM-HF试验显示沙库巴曲缬沙坦（LCZ696）治疗HF有极好的疗效,是过去20年内HF治疗领域的一个突破。本课题组已发表的研究显示,超大剂量ACEIS/ARBS治疗HF效果优于常规剂量。除此,随着对RAAS认识的不断深入,还发现了许多新的药物作用靶点,为临床治疗HF提供了新策略。本文旨在对以上内容做一综述。     

心力衰竭病人心房利钠肽与肾素-血管紧张素-醛固酮系统的关系

目的 研究慢性充血性心力衰竭病人心房利钠肽（atrial natriuretic peptide,ANP）与肾素-血管紧张素-醛固酮系统的关系。方法 采用放射免疫分析法测定对受试者血浆血管紧张素Ⅱ（angiotensinⅡ,ATⅡ）、醛固酮（aldosterone,ALD）及ANP含量。结果 心力衰竭组血浆ANP、ATⅡ、AID显著高于对照组,治疗后血浆水平均下降,与治疗前差异有统计学意义（P〈0．001）。ANP水平与ATⅡ水平呈正相关（P〈0．01）,与ALD水平呈正相关、（P〈0．05）。结论 同步监测ATⅡ、ALD、ANP有助于早期发现心力衰竭,判断病情及预后。     

Role of the renin-angiotensin-aldosterone system in atrial fibrillation and cardiac remodeling

PURPOSE OF REVIEW: This review summarizes recent clinical trial evidence showing a reduction in the development and recurrence of atrial fibrillation with angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor-blocking agents (ARBs). It then explores the possible mechanisms for this effect based on current animal models and limited human study. RECENT FINDINGS: Post hoc analyses of trials in patients with heart failure, hypertension, or myocardial infarction have observed reductions in atrial fibrillation among patients treated with ACE inhibitors or ARBs. Recent studies of these agents in animal models of atrial fibrillation suggest that they may prevent atrial fibrillation by reversing the cardiac structural and electrical changes, known as cardiac remodeling, that lead to the development of atrial fibrillation. This concept is also supported by two prospective studies showing that ACE inhibitors and ARBs prevent the recurrence of atrial fibrillation after electrical cardioversion. SUMMARY: Inhibition of the renin-angiotensin-aldosterone system is a novel concept for the treatment of atrial fibrillation that may target the underlying substrate of atrial fibrillation. Further human research is required to determine whether ACE inhibitors and ARBs prevent atrial fibrillation, and if so, whether this is a result of blood pressure lowering alone or a specific effect of these agents. Ongoing research will establish whether ACE inhibitors or ARBs have specific benefits in patients with atrial fibrillation.     

心房重构在房颤中的作用

房颤的发病机制非常复杂,与心房的重构(包括电学重构、解剖重构和自主神经系统重构)密切相关.房颤可诱导离子通道蛋白表达和(或)功能异常,进而反馈性地促进心房功能性折返基质的形成,发生电学重构;循环往复的电学重构造成心房基质的改变,失活的心房肌细胞被纤维组织替代,心房逐渐纤维化,出现解剖重构;与此同时,心房广泛的纤维化进一步阻碍电冲动的传导,反过来加重电学重构;自主神经系统重构可通过正向反馈环机制促进房颤的维持和复发.早期治疗心房重构可延迟甚至预防房颤的发生和发展.     

Morphological remodeling in atrial fibrillation

In the recent years, a tremendous amount has been learned about the pathophysiology of atrial fibrillation (AF). AF induces electrophysiological changes in the atria causing a perpetuation of the arrhythmia ("electrical remodeling"). Besides such AF-induced electrophysiological changes, which involve the downregulation of L-type calcium channels and thereby the calcium inward current, AF induces structural and ultrastructural changes in atrial tissue ("structural remodeling"). Calcium-dependent tissue alterations are induced by proteases and phosphatases like calpain and calcineurin. Furthermore, cardiac diseases like hypertension, heart failure, etc. activate the atrial angiotensin II system, and thereby, a progressive pro-arrhythmogenic atrial fibrosis is induced. Besides first clinical trials assessing the antiarrhythmic effects of angiotensin II receptor blockers in patients with AF, experimental data suggest that viral gene transfer can be used to transform fibroblasts to electrically conducting cardiomyocytes. This highly interesting methodology may be helpful to restore electrical conduction in fibrotic cardiac tissue.     

Structural remodeling in atrial fibrillation

Atrial fibrillation occurs and maintains itself in the context of a morphologically and functionally altered atrial substrate that can be induced by stressors such as underlying diseases (cardiac or noncardiac) or aging. The resultant structural remodeling is a slow process that progressively affects myocytes and the myocardial interstitium, and takes place from as early as the first days of atrial tachyarrhythmia. The left atrium, and particularly its posterior wall, is the location where remodeling is concentrated to the greatest extent. The mechanisms that underlie the remodeling process in atrial fibrillation have not yet been completely elucidated, although experimental and clinical investigations have indicated a number of signaling systems, inflammation, oxidative stress, atrial stretching and ischemia as factors involved in the cascade of events that leads to atrial fibrillation. The aim of this Review is to provide a comprehensive overview of the morphological changes that characterize the fibrillating atrial myocardium at histological and ultrastructural levels, and the established and hypothetical pathogenetic mechanisms involved in structural remodeling. This article also highlights the emerging therapies being developed to prevent progression of atrial fibrillation.     

The renin-angiotensin-aldosterone system and vascular remodeling

Cardiac fibrosis can be accompanied initially by diastolic and ultimately by systolic ventricular dysfunction. Clinical and experimental evidence suggests a clear association between such adverse structural remodeling and activation of the circulating renin-angiotensin-aldosterone system (RAAS). Infusion of either of two RAAS effector hormones, angiotensin II and aldosterone, in rats evokes perivascular fibrosis of arteries and arterioles of the heart and kidneys. Additionally, increasing evidence indicates locally produced angiotensin II and aldosterone have important paracrine and autocrine actions that play a role in vascular remodeling. Both angiotensin II and aldosterone receptor antagonists have been shown to attenuate the appearance of cardiac and renal fibrosis.     

心房颤动与心房重构的最新进展

心房颤动（房颤,AF）是引起心血管发病和死亡的重要原因.房颤是常见的由一系列心脏疾病引起心房重构的终点事件,其本身也能引起心房重构从而促进心律失常的发展[1].随着人们对心房重构的机制及其在房颤进展中作用的逐渐认识,对离子通道调控机制和作用靶点的研究也有了较深入的发展.本文将重点综述这方面的进展.     

钙信号调节异常在房颤电重构过程中的作用

心房颤动（AF）是一种多因素导致的疾病,持续性AF后期不可避免要有结构上出现相应的改变,故在早期电重构期进行针对性的治疗很有必要。本文主要从AF电重构产生的生理基础、AF患者钙信号的改变及AF药物治疗的新思想方面做一综述。