Effects of febuxostat on atrial remodeling in a rabbit model of atrial fibrillation induced by rapid atrial pacing

Background Febuxostat,a novel nonpurine selective inhibitor of xanthine oxidase(XO),may be used in the prevention and management of atrial fibrillation(AF).The purpose of this study was to evaluate the effects of febuxostat on atrial remodeling in a rabbit model of AF induced by rapid atrial pacing(RAP)and the mechanisms by which it acts.Methods Twenty-four rabbits were randomly divided into four groups:sham-operated group(Group S),RAP group(Group P),RAP with 5 mg/kg per day febuxostat group(Group LFP),and RAP with 10 mg/kg per day febuxostat group(Group HFP).All rabbits except those in Group S were subjected to RAP at 600 beats/min for four weeks.The effects of febuxostat on atrial electrical and structural remodeling,markers of inflammation and oxidative stress,and signaling pathways involved in the left atrium were examined.Results Shortened atrial effective refractory period(AERP),increased AF inducibility,decreased mRNA levels of Cav1.2 and Kv4.3,and left atrial enlargement and dysfunction were observed in Group P,and these changes were suppressed in the groups treated with febuxostat.Prominent atrial fibrosis was observed in Group P,as were increased levels of TGF-β1,Collagen I,andα-SMA and decreased levels of Smad7 and eNOS.Treatment with febuxostat attenuated these differences.Changes in inflammatory and oxidative stress markers induced by RAP were consistent with the protective effects of febuxostat.Conclusions This study is the first to find that febuxostat can inhibit atrial electrical and structural remodeling of AF by suppressing XO and inhibiting the TGF-β1/Smad signaling pathway.

Analysis of Incidence of Atrial Fibrillation after Implantation of VVI Pacemaker-Long-term Observation of 154 Patients

Incidence of occurrence of atrial fibrillation (Af) after implantation of VVI was examined and the possible mechanism was explored. Eighty cases of atriouentricular block (AVB) and 74 cases of sick sinus syhdrome (SSS) were studied and followed up for 1-14 years after implantation of VVI. The endpoint was the occurrence of permanent Af. The results showed that the incidence of Af among the 154 patients was 14.3 % (22/154). And the incidence was 2. 5 % among patients with AVB (2/80), and 27 % among patients with SSS (20/74). Significant significance was found between patients with AVB and those with SSS (P<0. 01). Among the patients with SSS, the incidence was 33. 3 % (9/27) in type I, 38.1 % (8/21) in type Ⅲ and 11. 5 % (3/26) in type Ⅱ. Significant differences were revealed among patients with Ⅱ, Ⅲ and Ⅱ type SSS (P<0. 05). It is concluded that retrograde conduction of pure ventricular pacing may play the chief role of occurrence of Af.

Selective his bundle pacing eliminates crochetage sign:A case report

BACKGROUND Crochetage sign is a specific electrocardiographic manifestation of ostium secundum atrial septal defects(ASDs),which is associated with the severity of the left-to-right shunt.Herein,we reported a case of selective his bundle pacing(SHBP)that eliminated crochetage sign in a patient with ostium secundum ASD.CASE SUMMARY A 77-year-old man was admitted with a 2-year history of chest tightness and shortness of breath.Transthoracic echocardiography revealed an ostium secundum ASD.Twelve-lead electrocardiogram revealed atrial fibrillation with a prolonged relative risk interval,incomplete right bundle branch block,and crochetage sign.The patient was diagnosed with an ostium secundum ASD,atrial fibrillation with a second-degree atrioventricular block,and heart failure.The patient was treated with selective his bundle pacemaker implantation.After the procedure,crochetage sign disappeared during his bundle pacing on the electrocardiogram.CONCLUSION S-HBP eliminated crochetage sign on electrocardiogram.Crochetage sign may be a manifestation of a conduction system disorder.

Molecular mechanisms of early atrial remodeling by rapid atrial pacing in rabbits

Objective: To establish a rabbit atrial fibrillation model with rapid atrial pacing (RAP) and investigate its ultrastructural changes and expressions of L-type calcium channel subunits and potassium channel Kv4. 3. Methods: Thirty-six rabbits were performed electrical stimulation through bipolar endo-cardial led by surgical technique. 600 beat per min from 0 to 48 h. Atrial ultrastructure was observed by transmission electron microscope (TEM) after different pacing times. mRNA were measured by reverse transcription-polymera.se chain reaction (RT-PCR). Results: Atrial ultrastructure had alteration after 3 hours' pacing, such as mitochondria vacuolization, myofilament lysis and glucogen aggregation. The mRNA of the Ca2+ channel β1 and α1 subunits began to decrease after pacing of 6 h. which were paralleled with the change of Kv4. 3 mRNA. But the auxiliary subunit α2 were not affected. Conclusion: Ultrastructural changes and mRNA levels of L-type calcium channel subunits and potassium channel Kv4. 3 are decreased after RAP. with a mechanism of transcriptional down-regulation of underlying ion channels due to calcium overloading after RAP.

Does Minimizing Ventricular Pacing Reduce the Incidence of Atrial Fibrillation ? A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background:Right ventricular pacing disrupts atrioventricular synchrony and increases the risk of atrial fi brillation(AF).However,whether algorithms for minimizing ventricular pacing reduce the incidence of AF remains controversial.Therefore,we conducted a systematic review and meta-analysis to compare the incidence of AF between minimizing ventricular pacing and conventional pacing protocols in patients with pacemakers implanted.Methods:The PubMed,Embase,and Cochrane Library databases were searched up to August 1,2017,for randomized controlled trials that reported the incidence of AF in patients with and without the use of algorithms for minimizing ventricular pacing.Results:Eleven studies comprising 5705 participants(61%males,mean age 71 years[standard deviation 11 years])were fi nally included in the analysis.The mean follow-up duration was 24 months.Use of algorithms for minimizing ventricular pacing signifi cantly reduced the incidence of AF,with an odds ratio of 0.74(95%confi dence interval 0.55–1.00;P<0.05).There was moderate heterogeneity among studies(I 2=63%).Conclusions:The incidence of AF was reduced by 26%with use of algorithms for minimizing ventricular pacing.The incorporation of such algorithms in routine clinical practice should in theory lead to a decrease in AF-related morbidity and mortality.

A case of recurrent PMT caused by poor atrial pacing

Pacemaker mediated tachycardia(PMT)can occur in patients with DDD pacemaker implantation,and PMT in narrow sense is a kind of circular motor tachycardia,which is often caused by ventricular atrial retrograde conduction.This paper reports a case of patients with high atrial pacing value in the early stage of pacemaker implantation,resulting in atrial retrograde conduction and recurrent PMT,Almost non-stop.Although the pacemaker has the PMT automatic termination procedure,PMT is still a short array of repeated attacks due to the presence of poor atrial pacing,resulting in the patients with shortness of breath,lower extremity edema and other heart failure symptoms.Finally,PMT was stopped by prolonging PVARP,and its lower starting frequency was slowed down to 50bpm,and AV interval was kept unchanged for 250ms,so as to reduce the release of atrial pulse and encourage the emergence of self selling down-propagation excitation.The proportion of atrial and ventricular pacing was significantly reduced,which not only saved the electric energy of pacemaker,but also conformed to the physiology.In a narrow sense,pacemaker mediated tachycardia(PMT)is a kind of circular motor tachycardia,which is often caused by reverse ventricular conduction.Repeated attacks for a long time may affect the patient's heart function.Although most modern pacemakers have PMT automatic termination procedures,they are still relatively passive in the presence of some induced factors.Finally,it is necessary to extend PVARP to truly terminate and prevent PM.A case of recurrent PMT due to poor atrial pacing is reported.

Implantation of Lumenless Pacing Leads at the Inter-atrial Septum and Right Ventricular Outflow Tract with Deflectable Catheter-sheath

Current permanent right ventricular and right atrial endocardial pacing leads are implanted utilizing a central lumen stylet. Right ventricular apex pacing initiates an abnormal asynchronous electrical activation pattern, which results in asynchronous ventricular contraction and relaxation. When pacing from right atrial appendage, the conduction time between two atria will be prolonged, which results in heterogeneity for both depolarization and repolarization. Six patients with Class Ⅰ indication for permanent pacing were implanted with either single chamber or dual chamber pacemaker. The SelectSecure 3830 4-French （Fr） lumenless lead and the SelectSite C304 8.5-Fr steerable catheter-sheath （Medtronic Inc., USA） were used. Pre-selected pacing sites included inter-atrial septum and right ventricular outflow tract, which were defined by ECG and fluoroscopic criteria. All the implanting procedures were successful without complication. Testing results （mean atrial pacing threshold： 0.87 V; mean P wave amplitude： 2.28 mV; mean ventricular pacing threshold： 0.53V; mean R wave amplitude： 8.75 mV） were satisfactory. It is concluded that implantation of a 4-Fr lumenless pacing lead by using a streerable catheter-sheath to achieve inter-atrial septum or right ventricular outflow tract pacing is safe and feasible.

Autonomic mechanism for chronic atrial electrical remodeling induced by rapid atrial pacing in ambulatory danines

Objetives The mechanism for changes in the electrophysiological properties of the atria during rapid pacing induced atrial fibrillation(AF) is not well understood.We aimed to investigate the contribution of intrinsic cardiac autonomic nervous system(ICANS) in chronic atrial electrical remodeling and AF induced by rapid atrial pacing for 4 weeks. Methods Twelve adult mongrel dogs weighing 15 to 20 kg were assigned to two groups;group 1(experimental group,n= 7) and group 2(control group,n =5).All dogs were anesthetized with propofol and mechanically ventilated via endotracheal tubes.The chest was entered via bilateral mini-thoracotomy at the fourth intercostals space.Bipolar pacing electrode was sutured to the right atrial appendage.Four-electrode catheters(Biosense-Webster,Diamond Bar,CA) were secured to allow recording at the right and left atriaum.All tracings from the electrode catheters were amplified and digitally recorded using a computer-based Bard Laboratory System (CR Bard Inc,Billerica,MA).Electrograms were filtered at 50 to 500 Hz.Continuous rapid pacing(600 bpm, 2×threshold[TH]) was performed at the right atrial appendage. Ganglionated Plexi(GP) was localized by applying high frequency stimulation(HFS;20 Hz,0.1ms duration, 0.5 to 4.5 V)with a bipolar stimulation-ablation probe electrode (AtriCure,West Chester,OH).Group1 underwent ablation of bilateral GP and ligament of Marshall followed by 4-week pacing.Group 2 underwent sham operaton without ablation of GP and ligament of Marshall followed by 4-week pacing.The effective refractory period(ERP) and window of vulnerability(WOV) were measured at 2×TH before(baseline) and every week after GP ablation.WOV was defined as the difference between the longest and the shortest coupling interval of the premature stimulus that induced AF.GP consist of the anterior right ganglionated plexi(ARGP) located in the fat pad at the right superior pulmonary vein(RSPV)-atrial junction;the inferior right ganglionated plexi(IRGP) located at the inferior vena cava/right atrial junction;the superior left ganglionated plexi(SLGP) at the left superior pulmonary vein(LSPV) /left atrial junction and the inferior left ganglionated plexi(ILGP) at the left inferior pulmonary vein (LIPV)/left atrial junction.Results Immediately after ablation, the ERP in Group 1 became markedly longer and started to shorten gradually during the first 2 weeks,then stabilized at the 4th week.Compared to Group2,the ERP of Group1 was significantly longer in the first 3 weeks(P【 0.05),but no obvious difference at the 4th week in either the right or left atrium(P】0.05).In Group 1,AF could not be induced(WOV=0)in the first 3 weeks after ablation, and at the 4th week,AF was induced in 2 of 7 dogs.In Group2,WOV progressively widened during the 4-week period. AF could not be induced in 5 of 7 dogs in Group 1 and 1 of 5 dogs in Group 2 during the 4-week pacing period. Conclusions The intrinsic cardiac autonomic nervous system (ICANS) plays an important role in the early stage of atrial electrical remodeling induced by rapid atrial pacing.On the other hand,with time passing by,its effect on the formation of AF decreases gradually,which suggests that ICANS may account for a non-dominant factor in the late stage of the rapid pacing-induced chronic atrial fibrillation.

Effects of atrial septal defects on the cardiac conduction system

The case report presented in this edition by Mu et al.The report presents a case of atrial septal defect(ASD)associated with electrocardiographic changes,noting that the crochetage sign resolved after Selective His Bundle Pacing(S-HBP)without requiring surgical closure.The mechanisms behind the appearance and resolution of the crochetage sign remain unclear.The authors observed the dis-appearance of the crochetage sign post-S-HBP,suggesting a possible correlation between these specific R waves and the cardiac conduction system.This editorial aims to explore various types of ASD and their relationship with the cardiac con-duction system,highlighting the diagnostic significance of the crochetage sign in ASD.

Dual-chamber pacing confers better myocardial performance and improves clinical outcomes compared to single-chamber pacing

The deleterious effects of long term right ventricular pacing are increasingly being recognized today.Current clinical practice favors the implantation of dual-chamber permanent pacemaker which maintains atrioventricular synchrony and is associated with better quality of life.However,despite the popular belief and common sense surrounding the superiority of dual-chamber pacing over single chamber pacing,the same has never been conclusively verified in clinical trials.Some observational evidence however,does exists which supports the improved cardiac hemodynamics,lower the rate of atrial fibrillation,heart failure and stroke in dual-chamber pacing compared to single-chamber pacing.In the index study by Haque et al,right ventricular pacing,particularly in ventricular paced,ven-tricular sensed,inhibited response and rate responsive pacemaker adversely im-pacted the left ventricular functions over 9-months compared to dual pacing,dual sensing,dual responsive and rate responsive pacemaker.Although there are key limitations of this study,these findings does support a growing body of evidence reinstating the superiority of dual chamber pacing compared to single chamber pacing.

Future easy and physiological cardiac pacing

The right atrial appendage (RAA) and right ventricular apex (RVA) have been widely considered as conventional sites for typical dual-chamber atrio-ventricular cardiac (DDD) pacing. Unfortunately conventional RAA pacing seems not to be able to prevent atrial fibrillation in DDD pacing for tachycardia-bradycardia syndrome, and the presence of a left bundle branch type of activation induced by RVA pacing can have negative effects. A new technology with active screw-in leads permits a more physiological atrial and right ventricular pacing. In this review, we highlight the positive effects of pacing of these new and easily selected sites. The septal atrial lead permits a shorter and more homogeneous atrial activation, allowing better prevention of paroxysmal atrial fibrillation. The para-Hisian pacing can be achieved in a simpler and more reliable way with respect to biventricular pacing and direct Hisian pacing. We await larger trials to consider this "easy and physiological pacing" as a first approach in patients who need a high frequency of pacing.

Minimizing right ventricular pacing in sinus node disease: Sometimes the cure is worse than the disease

Traditional right ventricular(RV) apical pacing has been associated with heart failure, atrial fibrillation and increased mortality. To avoid the negative consequences of RV apical pacing different strategies have been developed, among these a series of pacing algorithms designed to minimize RV pacing. These functions are particularly useful when there is not the need for continuous RV pacing: intermittent atrioventricular blocks and, mainly, sinus node disease. However, in order to avoid RV pacing, the operationalfeatures of these algorithms may lead to adverse(often under-appreciated) consequences in some patients. We describe a case of a patient with sinus node disease, in whom right atrial only pacing involved long atrio-ventricular delay to allow intrinsic ventricular conduction, which led to symptomatic hypotension that could be overcome only by "forcing" also right ventricular apical pacing. We subsequently discuss this case in the context of current available literature.

心律失常与起搏领域临床研究2023年度进展

回顾2023年心律失常领域重要临床试验,涉及心房颤动(房颤)、起搏等方面。CIRDADOSE研究及EARLY-AF研究均肯定冷冻球囊消融治疗房颤疗效,减慢房颤进展。MANIFEST-PF研究回顾房颤脉冲场消融的成功率及安全性,在ADVENT研究中再次证实其安全性和有效性不劣于传统热消融。在左束支区域起搏(LBBAP)研究中,与双心室起搏(BVP)相比,LBBAP降低持续性室性心动过速(VT)/心室颤动(VF)和新发房颤发生率。对于起搏比例高且射血分数降低的起搏器或植入式心律转复除颤器(ICD)患者,BUDAPEST CRT升级研究肯定了其升级到心脏再同步除颤器(CRT-D)的明确获益。DANPACEⅡ研究显示窦房结功能障碍患者的心房起搏最小化并不能降低房颤的发生率。IDE研究显示Aveir DR双腔无导线起搏器术后3个月安全性良好,可提供可靠的心房起搏和房室同步。iSUSI研究是对皮下植入式心律转复除颤器的注册研究,发现心力衰竭和非心力衰竭患者不恰当和恰当电击率相似。

左束支区域起搏对房室传导阻滞患者术后新发房性心律失常的影响

目的探讨左束支区域起搏(left bundle branch area pacing,LBBaP)对房室传导阻滞(AVB)患者术后新发心房颤动(new-onset atrial fibrillation,NOAF)和心房高频事件(atrial high rate episodes,AHREs)的影响。方法回顾性纳入84例行起搏治疗的三度房室传导阻滞(ⅢAVB)患者,根据心室电极位置分为LBBaP组(n=42)和右室间隔部起搏(RVSP)组(n=42)。比较两组患者术前术后QRS波时限(QRSd)、心室起搏参数,并发症、脑卒中事件和NOAF、AHREs发生率。结果(1)LBBaP组术后NOAF、AHREs发生率均低于RVSP组(P<0.05)。(2)LBBaP组的p-QRSd短于RVSP组(P<0.05)。(3)两组患者心室起搏参数、并发症及脑卒中事件发生率之间差异无统计学意义(P>0.05)。结论相对于右室起搏,LBBaP术后AHREs、NOAF的发生率较低,可改善患者预后。

基于心肌细胞β1-AR通路探讨脉神同调法对交感型阵发性房颤大鼠的作用

目的 观察定颤方对交感型阵发性心房颤动(atrial fibrillation, AF)大鼠电生理和心肌细胞肾上腺素能β1受体(β1-adrenergic receptor, β1-AR)信号通路的影响,探索其“脉神同调”治疗AF的潜在机制。方法 48只SD大鼠随机分为空白组、模型组、定颤方组(10.67 g/kg)和胺碘酮组(52.89 mg/kg),每组12只,连续灌胃给药14 d。实验第12天起,除空白组,其余组大鼠每日腹腔注射异丙肾上腺素(isoprenaline, ISO)1.5 mg/kg,连续3 d。第14天时,除空白组外,其余各组大鼠均行经食道心房Burst刺激进行AF诱发,观察各组大鼠有效不应期、AF诱发率和AF持续时间。采用ELISA测定各组大鼠血清去甲肾上腺素(norepinephrine, NE)水平;Western blot和RT-qPCR检测心房肌组织中β1-AR、蛋白激酶A(protein kinase A, PKA)、L型钙通道(L-type calcium channel, Cav1.2)蛋白和m RNA表达情况。结果 与空白组比较,模型组大鼠NE,β1-AR蛋白和m RNA,PKA m RNA水平升高(P<0.01),Cav1.2蛋白和m RNA水平降低(P<0.05);与模型组比较,定颤方组和胺碘酮组大鼠AF诱发次数明显减少(P<0.01),AF持续时间显著缩短(P<0.05),β1-AR蛋白和m RNA、PKA m RNA表达显著下降(P<0.05),Cav1.2蛋白和m RNA表达显著增加(P<0.01),定颤方组大鼠血清NE水平明显减少(P<0.05)。结论 定颤方能够有效抑制AF的发生和维持,其机制与调节NE、β1-AR及钙离子通道有关,可能通过抑制交感神经活性、促进钙稳态发挥“脉神同调”治疗AF的作用。

应用叠加图快速分析动态心电图

目的探讨叠加图的原理及其在动态心电图分析中的应用。方法选择4例与形态信息有关的典型动态心电图病例(窦性心律+室性心律、窦性心律+房性心律、窦性心律+交界性心律、双腔起搏器DDD工作方式+VAT工作方式),结合Lorenz散点图、心电瀑布图、逆向技术分析并总结叠加图的原理及优势。结果室性心律呈宽QRS波形态,而窦性心律呈窄QRS波形态,通过叠加图可实现两种节律的快速分离;窦性心律P波直立,而房性心律P波倒置,通过叠加图可实现两种节律的快速分离;窦性心律P波直立,而交界性心律无P波,通过叠加图可实现两种节律的快速分离;双腔起搏器DDD工作方式下可见AP及VP双脉冲,而VAT工作方式下可见VP单脉冲,通过叠加图可实现两种起搏方式的快速分离。结论叠加图在分析包含形态信息变化的动态心电图中有独特优势,是快速分析动态心电图的另一高效工具。

SD大鼠房颤模型的构建及其外周血IL-17A变化的实验研究

目的建立一种发病机制、病理改变与临床接近且造模周期短的房颤小动物模型,并探讨白介素-17A(interleukin-17A,IL-17A)、C反应蛋白(C reactive protein,CRP)在房颤发生中的变化。方法 20只健康SD大鼠采用随机数字表法分为房颤组和阴性对照组,房颤组经食道快速心房起搏后,观察房颤诱发的情况,并记录房颤诱发前后心电图的改变。酶联免疫吸附法测定血浆中IL-17A、CRP的浓度,Masson三色染色法观察心房组织纤维化程度的改变。结果房颤组大鼠经食道快速心房起搏后,均造模成功,总诱发率为96%,持续时间为(45.52±60.88)s。与对照组比较,房颤组大鼠心率显著加快,QRS间期及QT间期均显著延长(P<0.05)。房颤组血浆中IL-17A、CRP水平较对照组均显著升高,且随房颤发生次数的增多浓度有上升趋势,房颤组心房纤维化程度较对照组严重,胶原容积分数显著增大,差异均有统计学意义(P<0.05)。结论经食道快速心房起搏方法构建房颤大鼠模型成功率高、重复性好、周期性短,是较理想的造模方法之一;IL-17A、CRP可能在房颤发生发展中起一定作用。

食管心房调搏术在新生儿快速型心律失常的应用价值

目的探讨食管心房调搏术(TEAP)在新生儿快速型心律失常的应用价值。方法收集进行TEAP电生理检查或复律的26例快速型心律失常新生儿的临床资料。结果 15例(58%)确诊为房室折返性心动过速,3例(12%)为窦性心动过速,3例(12%)为室速,2例(8%)为慢快型房室结折返性心动过速,2例(8%)为房性心动过速,1例(4%)为窦速伴心室预激。22例患儿进行了超速抑制,除2例房速和2例室速未能恢复窦律外,18例新生儿均成功复律。结论 TEAP能帮助诊断新生儿快速型心律失常,且能用于复律。

经食管心房调搏术诊治婴幼儿快速型心律失常临床分析

目的探讨食管心房调搏术(TEAP)对婴幼儿快速型心律失常的分型诊断和治疗效果。方法回顾分析2005年1月至2016年12月收住的86例年龄≤3岁,经药物治疗无效后行TEAP诊治的快速型心律失常患儿的临床资料。经体表和食管心电图确定阵发性室上性心动过速(PSVT)54例,房扑(AF)26例,房性心动过速(AT)3例,窦性心动过速伴Ⅰ°房室传导阻滞(AVB)、交界性异位性心动过速及特发性室速(IVT)各1例。根据病程中TEAP治疗次数对PSVT和AF患儿进行分组,分为单次治疗组和≥2次的多次治疗组,进行比较。结果 86例患儿中,男49例、女37例,中位数年龄56.00 d(16.75~250.00 d)。除1例PSVT但TEAP证实为窦速伴Ⅰ?-AVB者未超速转复,85例采用超速抑制法转复成功66例,总转复成功率77.6%;其中PSVT转复成功率90.7%,AF转复成功率57.7%,AT和IVT各1例复律成功。PSVT和AF患儿中,单次治疗组与多次治疗组患儿的年龄、性别、心室率以及伴发基础疾病构成比等差异无统计学意义(P>0.05)。PSVT伴心功能不全者占18.5%(10/54),AF伴心功能不全占30.8%(8/26)。PSVT和AF复律成功与患儿心功能不全无显著相关性(P>0.05)。结论婴幼儿快速型心律失常采用TEAP诊断准确、可靠;TEAP是紧急、快速终止药物难治性PSVT的有效方法,尤其对于伴有心功能不全者。

生理性心脏起搏的临床分析

目的:分析生理性起搏治疗各种缓慢性心律失常,改善患者心功能及生活质量的临床效果。方法:1999年8月到2005年3月行永久性人工心脏起搏器植入的患者共310例,其中植入心室抑制型(VVI)起搏器78例,双腔(DDD)起搏器164例,心室抑制型频率应答(VVIR)起搏器16例,双腔频率应答型(DDDR)起搏器52例。术后平均随访时间(36±1.8)个月,随访内容包括患者症状及生活质量、运动耐量、心功能。结果:除去由于房颤伴心室率过缓或长间歇而仅可植入单腔起搏器的患者外,本组病例DDD(R)起搏器植入率达82.4%。DDD起搏器(生理性起搏器)植入术后患者脑血管缺血症状全部消失,心功能不全明显改善,运动耐量也明显提高,无起搏器综合征、起搏器介导的心动过速的发生。非生理性起搏器植入术后脑缺血症状消失率为84.2%,心功能不全发生率明显高于生理性起搏组,12.3%的患者有起搏器综合征。结论:植入生理性心脏起搏器能改善患者心功能,提高生活质量,起搏器综合征发生率低,值得推荐。