基于433 MHz无线植入式起搏系统的研究与实现

为解决在建立快速心房起搏房颤模型时快速起搏系统对通信干扰、通信距离等问题,设计一种基于433MHz无线通信频率进行组建星型网络的低功耗可植入式起搏系统。该系统包括植入式起搏器、程控头和程控软件,起搏器由无线通信模块、起搏模块、心电采集模块、电源管理模块组成,程控头作为星型网络中间节点,经由上位机程控软件程控网络中的起搏器。介绍了系统各部分的硬件设计和软件流程,描述了该系统进行模拟实验和动物试验的结果,结果表明所设计系统和应用方法对快速心房起搏房颤模型是有效且可行的。     

心房颤动面面观（一）

心房颤动．简称”房颤”．是一种常见的心律失常，在有器质性心脏病的患者和老年人中发病率相当高。有些人房颤可能只发生一次．有些人房颤反复发作．严重影响生活质量。房颤还是血栓栓塞特别是脑栓塞的主要原因，脑栓塞可致残和致死。因此．房颤是比较棘手的心脏疾病之一，但是近年对房颤的认识及治疗有了很大进展。     

持续性房颤的治疗

浙江淳安读者唐某来信说：今年69岁．是一位退休教师。50余岁时感觉心脏有异常现象．逐渐发展到阵发性房颤．近几年来阵发性房颤不太感觉到了．但做心电图的结论的是心房颤动．心室率每分钟100次左右．医生说是持续性房颤。服用过半年多的“步长稳心颗粒”．但心室率仍是如此。请问我该如何治疗．怎样预防房颤引起的其他事件?     

监护仪房颤综合管理应用的临床意义

目的 为了提高心房颤动（房颤）心律失常的检测准确度,实现对房颤的科学化管理和评估,该研究提出了一种房颤综合管理工具,方便医护人员对房颤患者进行系统评估管理。方法 研究设计了一种房颤专业视图（AF View）,将房颤的事件报警和负荷等信息统一,集中呈现患者监测周期内的房颤事件统计分布数据和心率、血压、ST值等其他生理参数/特征的趋势数据,通过一份界面图,获取多个维度的汇总信息。同时AF View中的监测周期和监测参数/特征可以调整,便于获取不同时间周期下和不同参数/特征下的汇总信息,了解房颤患者的病情发展。结果 实现了房颤的精准检测和综合管理。结论 该研究所提出的房颤综合管理应用,有助于医护人员实时掌握房颤患者的病情发展,及时调整治疗方案。     

心律失常（二）

心房颤动（房颤）是老年人常见的心律失常，它主要是由于心房肌退行性变和纤维化等老年性改变．引起心房扩大．当心房异位冲动（如房早）传人心房后，刚好进入心房激动的易损期，加上心房肌老年性改变，因此，在心房内形成一个大的折返环，该折返环又引起4到6个子环，就导致房颤。大多数房颤开始为阵发性，一年仅发作1～2次，以后部分患者越发越频，变成持续性或慢性房颤，而另小部分患者可保持阵发性。     

房颤者莫忘抗血栓

房颤导致的脑卒中越来越多 房颤是最常见的持续性心律失常，55岁以上年龄每增加10岁．房颤的发生率就会加倍，65岁以上老年人发生率达到5％．80岁患病率大约10％。房颤病人的平均年龄为75岁．Framingham，心脏研究显示，50～59岁组房颤病人发生脑卒中的危险为1．5％，而80-89岁组达到了23．5％。随着人口老龄化和心脏疾病存活率的改善，房颤的患病率增加．因为房颤导致脑卒中越来越多。     

血液透析患者新发房颤的临床分析

目的：房颤是否增加维持性透析患者死亡率尚无定论。我们回顾分析了维持性血液透析患者的房颤发生率，并对其临床相关因素进行了探讨。方法：观察本中心2005年1月到2007年6月维持性血液透析超过3个月的患者，记录他们的年龄，透析方式，房颤发生情况及血红蛋白维持水平。结果：168例患者中，12例新发房颤，发生率为7．14％，年龄大于55岁的患者共90例，房颤发生率为11．45％，显著高于年龄小于55岁的患者。透析龄大于4年的房颤的发生率为11．11％，房颤患者和非房颤患者血红蛋白水平无明显差异。非房颤患者中有25例发生心梗或脑梗，发生率为15．15％，而房颤患者中发生两例脑梗，发生率为16．67％。结论：1．透析患者的房颤发生率高于普通人群；2．随着年龄的增加房颤的发病率增加，55岁以上的房颤发病率明显升高；3．随着透析年限的增加房颤的发病率也增加，血液透析4年以上房颤的发病率明显升高。     

心律失常问与答（3）

心房颤动有哪些治疗方法 房颤的治疗方法包括药物抗心律失常治疗或控制心室率，主要非药物治疗有电转复转复窦性心律．射频消融术等。房颤急性发作心室率快的，应立即到医院急诊使用抗心律失常药物反复发作出现阵发性房颤，或持续房颤发生的时间在6个月内的，可使用治疗控制房颤发生或药物转复房颤。     

房颤,不可轻视的疾病

<正>心血管疾病是全世界最大的"杀手",而房颤又是一种常见的心血管疾病。在我国,房颤患者估计在1000万以上。那么,哪些信号提醒房颤可能找上了门?平时又该如何预防房颤?心慌、头晕,当心是房颤房颤患者心房的颤动频率,每分钟可达到300~600次。心脏可以简单地分为心房和心室两大部分,在每个人的心房上都有一个窦房结,窦房结的作用是发出规律的电信号来控制整个心脏,称为窦     

心房除颤电场分布仿真的电极位置与尺寸优化

该文提出了一种基于心脏建模及有限元求解的心房除颤电场分布仿真方法，用于分析动物实验和临床验证均无法精确测量的心脏除颤电场分布，为电除颤方法研究提供工具。该研究使用包含完整的心房解剖结构的心脏模型，采用有限元方法进行求解；并设计了由除颤电压阈值、高场强率、除颤能量阈值三个参数组成的评价指标体系评价除颤效果。对经静脉房颤除颤时不同电极位置与尺寸的心脏电场分布进行了仿真研究，结果与文献报道有相当好的吻合度，初步验证了该方法的可行性。     

心房快速起搏动物模型刺激器的设计与应用

该文设计一种用于心房快速起搏动物模型的刺激器。刺激器可根据临床研究的需要,设计刺激输出脉冲频率,通过体外控制实现刺激器的启停。并通过动物实验,初步验证了刺激器用于心房颤动模型建立的有效性。     

急性胰腺炎动物模型研究进展

动物模型是认识和研究人类疾病的重要工具。为探讨胰腺炎的发病机制、病因、病理生理及治疗方法，已经建立了众多的活体胰腺炎动物模型。由于活体胰腺炎模型具有操作简单、容易控制、便于观测全身变化指标和利于治疗研究等优点，目前应用较广泛，正确选择动物模型是进行胰腺炎研究的基本条件之一。本研究探讨几种常用的胰腺炎动物模型，可使我们更加了解胰腺炎的发病机制，为临床提供更好的治疗方法。     

Biatrial pacing--new possibility in the non-pharmacologic treatment of drug-resistant paroxysmal atrial fibrillation

Biatrial pacing seems to be a possible non-pharmacological therapeutic choice in the prevention of drug-refractory, paroxysmal atrial fibrillation. Biatrial pacing using standard right atrial and coronary sinus left atrial pacing shows an antiarrhythmic effect, which mechanism is not well understood. Biatrial pacemaker was implanted in three patients suffering from drug refractory, symptomatic paroxysmal atrial fibrillation (lone and nonvalvular in 2 and in one case, respectively). Interatrial conduction disturbance (P > 120 ms) was found in three case. Bradycardia dependent arrhythmia development was not observed. Left atrial and right atrial premature beats dominated in 2 and in one case, respectively. P-wave duration was decreased by biatrial pacing in every patients. Atrial fibrillation has not been detected in two patients 1 day and 4 weeks after pacemaker implantation (follow up period: 9 and 5 months), however antiarrhythmic drugs has been withdrawn. In the number of left atrial premature beats a marked decrease was observed. Neither biatrial nor standard right atrial pacing nor combined medical and atrial pacing antiarrhythmic therapy were proven to be effective. In Hungary we were the first to implant and apply effectively biatrial pacemaker in the prevention of paroxysmal drug-refractory atrial fibrillation. However better identification the responding patients subgroup with atrial fibrillation is needed.     

Indications for definitive cardiac stimulation

Within less than a half-century, after the early rising of cardiac pacing, we witness a dramatical in crease of its indications. After the initial aim, which was to prevent transient ischaemic events, and sudden death due to bradycardia, some more physiological objectives have--progressively appeared, such as improvement of patient's quality of life, and optimization of the cardiac performance to fulfill the metabolic needs. The indications of cardiac pacing are nowadays extended to the fields of haemodynamics and rythmology. Numerous studies are advocating the interest of the cardiac pacing in pathologies such as obstructive and dilated cardiomyopathies specially for the improvement of the NYHA functional status, life comfort and effort sustain. On another hand, newly discovered antiarrhythmic virtues of atrial pacing are of a great interest for a certain type of atrial fibrillations such as vagal induced fibrillations, atrial diseases and atypical flutters. For conclusion: after becoming mandatory for bradycardias, cardiac pacing is conquering new indications on the fields of arrhythmias and cardiomyopathies. Within a close future, scientific evidences could definitely validate ?ardiac pacing using on these new fields.     

Prevention of atrial fibrillation by atrial-based pacemaker implantation

A large number of studies have demonstrated the long term disadvantage of single lead ventricular pacing in sick sinus syndrome. Ventricular pacing mode predicts chronic atrial fibrillation in patients with preimplant paroxysmal atrial fibrillation. The goal of the report was to study the effectiveness of single atrial and dual chamber (atrio-ventricular sequential) pacemaker treatment in the prevention of atrial fibrillation for patients with sick sinus syndrome complicated with paroxysmal atrial fibrillation. In our university hospital 16 atrial based 5 and dual chamber 11 pacemaker were implanted for treatment of patients with sick sinus syndrome (with or without AV conduction disturbances) complicated with paroxysmal atrial fibrillation. The mean age were 61 (24-78), nine males and seven females. Before or during pacemaker implantation sinus node and AV node function analysis, and echocardiography were performed. There were no surgical complications, lead and/or generator failure. All patients had routine follow-up performed at 4 weeks, 3 months, 6 months. Mean follow up was 31 +/- 8 months (range 3 to 93 months). The atrial based and dual chamber pacing were effective in 90% of our cases. In one patient the treatment had to be combined with propafenone. According to our result, the atrial based pacing may be used to reduce the incidence of atrial fibrillation with careful programming of the base atrial pacing rate, and it is associated with lower frequencies of thromboembolic complications and pacemaker syndrome.     

Repolarization and refractoriness in patients with persistent atrial fibrillation

The use of monophasic action potential (MAP) recordings has been of important value during atrial fibrillation to understand the possibility of local pacing capture during the arrhythmia, while MAP and refractoriness determination after sinus rhythm restoration have highlighted the issue of electrophysiological remodeling owing to rate. Moreover the contemporary recording of MAP and refractoriness at the same atrial sites permitted to better understand the behavior of the ERP/MAP ratio in these patients. Local atrial pacing capture has been demonstrated in humans with chronic atrial fibrillation and suggests the presence of re-entrant circuits with large excitable gaps. The studies about atrial remodeling have shown a shortening of atrial ERP or monophasic action potential duration after cardioversion of persistent AF, while discordant results have been observed for what it concerns refractoriness adaptation to rate. Finally, the recording of a mean ERP/MAP90 ratio < 1 at all the pacing cycle lengths, indicates that no post-repolarization refractoriness was present after cardioversion of persistent atrial fibrillation.     

Pathophysiology and clinical management of atrial flatter

The authors review the current knowledge relating to the pathophysiology and treatment of atrial flutter, the most common supraventricular macroreentrant tachycardia. After an account of the historical and epidemiological data, the atrial tachycardia classification system based on the up-to-date North American + European consensus is presented. The main electrophysiological and electrocardiographic features of right atrial isthmusdependent typical and reverse typical flutter are detailed, as are those of the nonisthmus dependent, atypical forms. The electrophysiological connection between the very frequently coexisting atrial flutter and atrial fibrillation, and also the transitional form (flitter), are discussed. Following the clinical presentation, an account is given of the drug and non-pharmacological therapeutic modalities. It is pointed out that the recently-developed drugs with Vaughan Williams class 3 antiarrhythmic action, which block potassium channels and prolong atrial refractory period, are now primarily used (e.g. ibutilide, dofetilide). Effective means of terminating atrial flutter include transthoracic direct-current cardioversion (pretreated with antiarrhythmic = hybrid therapy) and transoesophageal or intraatrial overdrive pacing. It is stressed that the efficiency of prevention of atrial flutter with the antiarrhythmic drugs currently used even today is poor. Accordingly, the optimum mode of treatment of atrial flutter, which is primarily a method of first choice in special cardiac centres, is curative radiofrequency catheter ablation.     

食管起搏心电图空隙现象分析

目的探讨经食管心房调搏心电图现象。方法对经食管检查中出现刺激间期缩短到一定程度出现QRS-T波群脱落而刺激间期继续缩短后不可见QRS-T波群现象的5例患者进行心电图分析。结果5例患者心电图表现符合裂隙现象。结论掌握心电图中的裂隙现象的特征,能够避免经食管心房调搏检查中某些错误的诊断。     

食管起搏心电图空隙现象分析

目的探讨经食管心房调搏心电图现象。方法对经食管检查中出现刺激间期缩短到一定程度出现QRS-T波群脱落而刺激间期继续缩短后不可见QPS—T波群现象的5例患者进行心电图分析。结果5例患者心电图表现符合裂隙现象。结论掌握心电图中的裂隙现象的特征．能够避免经食管心房调搏检查中某些错误的诊断。     

Non-pharmacologic treatment of atrial fibrillation]

Curative non pharmacological treatment of AF includes MAZA anti arrhythmic surgery and ist different variants which are reserved to AF associated with mitral valve disease. Radiofrequency (RF) ablation of AF creating lesions mimicking the MAZE procedure is another curative treatment but its numerous complications lead to put it in stand-by. Focal AF radiofrequency ablation is the only curative method that has encouraging results. The development of the internal cardioversion led to the development of the implantable atrial defibrillator. In spite of the low energy used, the internal shocks are often painful and not well tolerated conducting to stop the use of these devices. Prophylactic atrial pacing among patients with interatrial conduction delay is well established by dual site pacing pioneers. After several attempts to restore sinus rhythm and the fail of drug therapy to reduce heart rate, the latest solution to prevent tachycardiomyopathy is the atrio-ventricular (AV) node modulation or ablation using RF energy.