离子通道病的种类和特点

遗传性室性心律失常可分为两大类：原发性心电疾病与致心律失常性心肌病。原发性心电疾病指无器质性心脏病的一类以心电紊乱为主要特征的疾病，包括长QT综合征(LQTS)、Brugada综合征、特发性室颤(IVF)、儿茶酚胺敏感的多形性室速(CPVT)、孤立性房颤，可能还包括遗传性心脏传导阻滞、不可预测的夜间猝死综合征、婴儿猝死综合征、短QT综合征等。     

急性冠脉综合征合并恶性心律失常的急诊处理

急性冠脉综合征(acute coronary syndrome,ACS)是因冠脉内急性血栓形成而导致心肌严重缺血产生的一组进行性的临床综合征[1,2].ACS的主要临床危害是可引起一系列严重的血流动力学障碍及心脏的严重并发症,如心肌的电不稳定性所导致的恶性心律失常、心肌坏死所致的心力衰竭或心脏破裂等[3],其中ACS合并的恶性心律失常,因起病急、进展快、死亡率高,必须给予急救处理[4,5]. 1 ACS合并的恶性心律失常分型与发生率 1.1恶性心律失常(malignant arrhythmias,MA) MA即致命性心律失常,一般指恶性室性心律失常.MA可在短时间内引起血流动力学障碍,导致患者晕厥,甚至猝死.绝大多数MA并发于器质性心脏病,只有少数特殊类型可为原发,如先天性QT延长综合征、Brugada综合征、特发性心室颤动等等.     

猝死的危险因素——机械电反馈

猝死是目前发展及发达国家面临的一个重大问题,因此有必要对猝死的发生机制和识别猝死高危患者的方法进行研究。多数猝死源于室性快速性心律失常,常有器质性心脏病及不同程度的心力衰竭。心力衰竭早期心脏机械特性改变,此时常合并动作电位延长。猝死的少见原因有原发性电紊乱(如Brugada综合征,长QT综合征)。     

SCN5A基因突变与心律失常的研究进展

近年来分子生物学及分子电生理的迅速发展,开创了心律失常机制研究新纪元。心律失常与离子通道基因表达异常明确相关,多个离子通道基因的突变可引起各种心律失常。目前,已知绝大多数的原发性心电异常都是由编码各主要离子通道亚单位的基因突变引起的,因此,这类病可称为“离子通道病”。Nav1.5通道是人类主要的心脏钠离子通道类型,负责动作电位的起始和传播,由SCN5A基因编码。自从在长QT综合征(long QT syndromeL,QTS)家系中发现心脏钠离子通道α亚基的编码基因SCN5A第一个突变以来,目前已经发现数百个突变与一系列遗传性心律失常有关,如长QT综合征3型(LQT3)、Brugada综合征、进展性心脏传导阻滞(PCCD)、扩张型心肌病(DCM)、婴儿猝死综合征(SIDS)等。近年来发现SCN5A基因突变与病态窦房结综合征(SSS),房性心律失常(心房颤动,心房静止),室性心律失常和起搏夺获不良密切相关。本文将详细阐述近年来SCN5A基因突变在SSS、房性心律失常(心房颤动,心房静止)、起搏夺获不良、室性心律失常和长QT综合征3型的研究进展,SCN5A功能获得性和功能丧失致病突变潜在的机制以及目前存在的问题和挑战。      

小儿心律失常的药物治疗

心律失常在儿童及青少年中十分常见,其中有的可致猝死,如长QT综合征、Brugada综合征等;有的发作频繁,可引起明显的症状,甚至导致心动过速性心肌病,因此小儿心动过速的治疗应引起儿科医师的高度重视。     

老年人阻塞性睡眠呼吸暂停低通气综合征心律失常的临床分析

阻塞性睡眠呼吸暂停综合征(OSAHS)与心律失常均为严重危害老年人健康的常见病,是引起高血压、冠心病、心脏猝死、脑卒中等疾病的独立危险因素。研究表明,OSAHS患者因心、脑血管病导致的死亡率明显高于正常人,睡眠中潜在的严重心律失常、传导阻滞是患者夜间引起猝死的原因之一。     

小儿心律失常的药物治疗

心律失常在儿童及青少年中十分常见,其中有的可致猝死,如长QT综合征、Brugada综合征等;有的发作频繁,可引起明显的症状,甚至导致心动过速性心肌病,因此小儿心动过速的治疗应引起儿科医师的高度重视.     

程序性心室刺激用于预测心脏结节病患者未来心律失常事件的价值

程序性心室刺激对心脏结节病患者未来心律失常事件的预测价值尚不清楚。在心脏结节病患者中,植入性心脏复律除颤器(ICD)的长期益处也同样不明确。连续32例心脏结节病患者接受了程序性心室刺激。出现自发性或可诱发持续室性心律失常的患者(n=12)接受ICD植入。对所有研究患者进行随访,观察适当的ICD治疗后联合心律失常事件终点或猝死。至出现持续室性心律失常或猝死为止,平均随访时间为32±30个月。6例自发性持续室性心律失常患者中的5例(83%)和6例无自发性但可诱发持续室性心律失常患者中的4例(67%)接受了适当的ICD治疗。20例既无自发性…     

第71届日本循环协会年会选萃(二)

缝隙连接结构重塑是重要的促心律失常因素临床上40%的慢性心衰(HF)患者死于猝死,主要由致命性心律失常如室性心动过速或心室纤颤等引起。多数学者认为,慢性心衰时心律失常的发生主要与心肌电学特性改变和解剖结构重构有关,具体机制涉及心脏负荷过重和心肌过度拉伸引起的离子通道变化、肾素-血管紧张素-醛固酮系统、自主神经系统以及细胞内调控机制如ryanodine受体和Na~+/Ca~(2+)交换机制等。     

老年退行性心脏瓣膜病与心率变异

老年退行性心脏瓣膜病(senile degenerative heart valvular diseases，SDHVD)又称老年钙化性心脏瓣膜病、老年性心脏瓣膜病或老年心脏钙化综合征，是随着年龄增长，心脏结缔组织退行性变而纤维化、钙化，从而使瓣膜和(或)其支架的功能异常引起的一组心脏病。随着超声诊断学的发展，其检出率不断提高，是老年人常见的心脏瓣膜病，可导致心律失常、心功能减退、心力衰竭以及猝死。     

心律失常相关microRNA的研究进展

心脏性猝死是目前威胁人类的主要疾病之一,其病因很多,主要由恶性心律失常引起。由于不能确切认识心律失常的发生机制,目前尚无有效方法预防和治疗心脏性猝死。近年来,发现microRNA(miRNA)在心脏生理病理过程中发挥重要的调控作用,尤其与心律失常的发生、发展密切相关。该文就miRNA在心律失常发生、发展中的作用予以综述。     

非侵入性心电学检查在心脏性猝死预测中的应用价值

心脏性猝死(SCD)是我国乃至全世界面临的严峻的公共卫生问题,严重危害人们身体健康。国外报道SCD占所有死亡人数的15%~20%。在发生SCD的人群中,非心脏疾病患者的比例高达50%,如何发现有效的预测指标以及早期识别SCD非常重要。目前非侵入性心电学检查仍以其操作安全易行的特点成为预测致命性室性心律失常和SCD风险的首选。本文主要结合近期研究进展,总结非侵入性心电学检查和相关指标在预测SCD中的应用价值。     

Sudden cardiac death and the potential role of beta-adrenoceptor-blocking drugs.

Sudden cardiac death is a major health problem in the industrially developed countries. The risk of sudden cardiac death may be reduced by early detection of coronary heart disease, elimination of the risk factors, treatment of the ischaemia in patients known to have coronary heart disease and suppression of ventricular arrhythmias. Of all the therapeutic measures currently available to reduce the risk of sudden cardiac death, beta-adrenoceptor-blocking drugs (beta blockers) appear to be the most effective. In this paper their actions are reviewed and evidence for their efficacy is presented.     

Sudden cardiac death among competitive adult athletes: a review

Sudden cardiac death is the leading cause of mortality among young athletes with an incidence of 1-2 per 100,000 athletes per annum. It is described as 'an event that is non-traumatic, non-violent, unexpected, and resulting from sudden cardiac arrest within six hours of previously witnessed normal health'. Most predisposed athletes have no symptoms and there is no warning for the impending tragic event. The majority of cases are caused by an underlying structural cardiac abnormality, most commonly hypertrophic cardiomyopathy. More recently, the understanding of non-structural causes such as long QT syndrome and Brugada syndrome has grown and diagnostic criteria have been developed. This review presents the known aetiologies of sudden cardiac death among athletes and outlines their identification and management including implications for future sporting participation as laid out in the consensus documents produced by the European Society of Cardiology and the 36th Bethesda Conference.     

The cardiac pathology of sudden, unexplained nocturnal death in Southeast Asian refugees

Sudden death during sleep has occurred among previously healthy Southeast Asian male refugees, but routine autopsies have not determined the cause of death in any of these cases. We report the first systematic attempt to define the cardiac abnormalities associated with this syndrome. Among 18 hearts examined, 14 showed slight to significant cardiomegaly, characteristic of increased cardiac work load. The reasons for the cardiomegaly remain unexplained. Conduction system anomalies were present in all but one heart. These included persistent fetal dispersion of the atrioventricular node and/or bundle of His, present in 14 hearts; accessory conduction fiber connections, found in 13 cases; and congenital heart block, observed in one case. These abnormalities were associated with variations in the structure of the cardiac base, suggesting a common aberrant developmental process. Although the functional significance of these findings has not been established, the conduction system anomalies may be the substrate for sleep-related cardiac arrhythmias and sudden death.     

QT离散度对扩张型心肌病的临床意义

目的探讨QT离散度(QTd)与扩张型心肌病(DCM)恶性室性心律失常和心功能的关系。方法对42例DCM患者按室性心律失常性质分为恶性室性心律失常组与非恶性室性心律失常组。并按心功能状态分为轻度心力衰竭组和重度心力衰竭组,另选40例无器质性心脏病者作为正常对照组,分别测定12导联心电图QT间期,并计算QTd、QTcd。结果(1)恶性室性心律失常组较非恶性室性心律失常组QTd、QTcd显著延长(P<0.01),非恶性室性心律失常组较正常对照组QTd、QTcd显著延长(P<0.01);(2)重度心力衰竭组较轻度心力衰竭组QTd、QTcd显著延长(P<0.05),轻度心力衰竭组较正常对照组QTd、QTcd显著延长(P<0.01)。结论QTd、QTcd对DCM患者恶性室性心律失常或猝死有一定预防价值,并可作为评价DCM患者心功能状态的一项辅助指标。     

Study of sudden cardiac deaths in young athletes

Sudden cardiac deaths in athletes are usually due to underlying cardiovascular disease. The final pathway is usually ventricular fibrillation following hypertrophic cardiomyopathy and coronary artery anomalies in young persons below the age of 30 years. Sudden cardiac death in young is rare but remains as a source of concern. A postmortem study was conducted to ascertain the cardiac causes of sudden death in persons below the age group 30 years following exercise in games or otherwise. Out of 15 cases in autopsy finding, hypertrophic cardiomyopathy (n=7) was the commonest cause followed by coronary artery anomalies (n=4). Sudden unexpected death is a source of concern and careful screening of history and physical examination for potential athletes should identify majority of people at risk.     

Bradycardia: an important physical finding in anorexia nervosa

Cardiovascular complications are common in patients with anorexia nervosa, an eating disorder resulting in severe malnutrition that affects multiple organ systems. Sinus bradycardia is the most common cardiovascular physical finding and the most common arrhythmia in patients with anorexia nervosa. It is important to appreciate the significance of sinus bradycardia in this clinical setting because it may be associated with sudden death, especially in the presence of other arrhythmias or EKG abnormalities, such as prolongation of the QTc interval. Since sinus bradycardia can occur in up to 95% of patients with anorexia nervosa, its clinical correlation with more lethal arrhythmias cannot be overemphasized. Physicians must be aware of the common cardiac findings on the physical examination of a patient with anorexia nervosa in order to refer those patients to tertiary care centers for treatment by eating disorder specialists.     

心力衰竭心源性猝死的研究进展

心源性猝死(SCD)是临床常见急重症,在心力衰竭患者中发病率较高。SCD发生由多种病因引起,其主要机制为心律失常。由于SCD病死率高,早期发现和预防在临床工作中显得尤为重要。近年来,关于SCD预警因素的研究越来越多,实验证明纽约心功能分级、左心室射血分数、心率变异性、T波交替及多种血清学指标均对SCD的预防具有指导意义,也进一步为SCD的治疗提供了客观依据。     

交感神经与心源性猝死

心源性猝死(sudden cardiac death, SCD)指因心血管原因造成的,突然发病1 h内或距离最后所知稳定状态24 h内的死亡,发病率高、存活率低。心脏自主神经尤其交感神经与SCD的关系是目前相关研究的焦点。交感神经兴奋性异常增高、交感神经分布不均及病理状态下的重塑均会造成心律失常易感性增高甚至诱发心源性猝死。药物治疗、植入型心律转复除颤器(implanted cardioverter defibrillator, ICD)预防及近年先后出现的星状神经节切除、肾动脉神经消融、脊髓刺激等均对减少心源性猝死的发生起到一定作用。因此,本文就心源性猝死与交感神经的关系以及相关的治疗措施作一综述。