双腔起搏器最小化心室起搏功能中心室起搏管理与房室间期自动搜索功能的比较分析

目的:比较最小化心室起搏中心室起搏管理(MVP)与房室间期自动搜索[Search AV(+)]功能对右室起搏比例(VP％)及左室射血分数(LVEF)的影响.方法:50例症状性窦缓、病态窦房结综合征、间歇性房室传导阻滞的患者,均安装双腔起搏器,分为MVP组和Search AV(+)组,程控MVP组关闭Search AV(+)功能,开启MVP功能;Search AV(+)组开启Search AV(+)功能.于术后随访,比较其6个月的心房起搏、心室起搏比例、高频心房事件次数,及LVEF的值.结果:50例患者完成随访,MVP组比Search AV(+)组的心室起搏比例、高频心房事件次数都显著降低,分别为(11.4±8.3)％,(36.7±7.4)％和(32±10)次,(86±16)次;6个月的LVEF值较术前有显著差异,两组心房起搏比例、12个月的LVEF值差异无统计学意义.结论:MVP功能与SearchAV(+)功能相比可更加减少不必要的右心室起搏,减少高频心房事件.     

Indications for pacing in the treatment of bradyarrhythmias. Report of an independent study group

Indications for permanent pacing in the bradyarrhythmias are summarized. In the absence of symptoms, pacing is justified only when Mobitz type II block or complete atrioventricular (AV) block is localized in the bundle-branch system. All other abnormalities of impulse generation or conduction (incomplete AV block of any type, atrial fibrillation with slow ventricular response, or sinus node dysfunction) must be shown to be stable and intrinsic and to cause CNS symptoms or hemodynamic compromise to justify pacing. Isolated intra-Hisian abnormality without failure of AV conduction is benign. Measurement of HV interval does not contribute significant information. Correlation of carotid sinus sensitivity with carotid sinus syncope is poor (5%). Bradyarrhythmia produced by minimal effective doses of an essential drug is a rare indication for pacing and requires special documentation. Inadequate indications, sources of error, and misconceptions are discussed. Generally, it is important to exclude drug effect, transient clinical states, and correctable systemic disease as causes of the abnormality before making a conclusion about pacing.     

LONG TERM PERFORMANCE OF STEROID-ELUTING LEAD IN DUAL CHAMBER PACING

The atrial pacing lead is believed having higher stimulation thresholds and long-term complicatinn rares than ventricular lead, this being one of the factors limiting the use of dual chamber pacing. A prospective study was undertaken to evaluate both atrial and ventricular bipolar tincd steroid-ehidng leade in long-term dunl chamber pacing. There are 81 pairs of leads (Medtronic Capsure SP) used in 81 patients.Bipolar atrial and ventrieular stimulation thresholds were measured immediately post implantatlon and 1,3,6,12,18 and 24 months. All leads demonstrated low mean stimulation thresholds during the follow-up and more than 94% of leads could be paced chronically in the atrium and ventricle at 2.5 volts. In conclusion,atrial and ventricular steroid-during leads gave excellent stimulation thresholds allowing low energy longterm dual chamber pacing.     

置入双腔起搏心脏复律除颤器及经腋静脉送入心内电极的初步临床体会

目的　初步评价新型双腔起搏心脏复律除颤器抗室性心动过速 /室颤 (VT/VF)及心动过缓起搏的临床效果 ,了解经腋静脉送入心房及心室电极的安全性及有效性。方法　 7例室性心动过速及或室颤同时伴有心动过缓患者接受了双腔起搏心脏复律除颤器治疗 ,其中冠心病 5例、扩张性心肌病 2例。心房及心室电极均在X光线透视、静脉注入造影剂指导下 ,直接穿刺腋静脉 ,从该静脉送入。结果　脉冲发生器埋在左上胸皮下 5例 ,胸大肌与胸小肌之间 2例。仪器对所有VT/VF均能及时识别并成功治疗 ,同时提供有效的房室顺序起搏功能。所有心内电极均成功地经腋静脉送入 ,无并发症。结论　双腔起搏心脏复律除颤器不但能有效地治疗严重室性心律失常 ,而且能提供可靠的房室顺序性起搏功能 ,且经腋静脉送入电极安全 ,可靠。     

肌肉注射胃复安预处理对食管心房调搏检查结果阳性率及假阳性率的影响

目的 探讨肌肉注射胃复安预处理对食管心房调搏检查结果阳性率及假阳性率的影响.方法 拟行食管心房调搏检查的患者120例,随机分为试验组(n=63)和对照组(n=57),试验组食管心房调搏前20 min肌注10 mg胃复安注射液,对照组肌注等体积生理盐水,比较两组食管心房调搏检查结果的阳性率和假阳性率.结果 两组患者窦房结功能不良阳性率、房室折返性心动过速阳性率比较,差异无统计学意义(P>0.05).试验组房室结双径路阳性率、房室结折返性心动过速(AVNRT)阳性率和总阳性率高于对照组;可疑窦房结功能不良假阳性率、房室前传功能障碍假阳性率低于试验组(均P<0.05).结论 肌肉注射胃复安预处理能提高食管心房调搏的房室结双径路和AVNRT诊断阳性率,降低可疑窦房结功能不良假阳性率和房室传导功能障碍假阳性率,值得在临床推广.     

Percutaneous balloon aortic valvuloplasty in the treatment of congenital valvu lar aortic stenosis in children

Objective To assess the effect of the balloon valvuloplasty for congenital valvular aortic stenosis (AS) in children.Methods A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV).The ratios of balloon/valve were 0.95±0.08 for 19 cases of typical AS and 1.00±0.11 for 8 cases of hyp oplastic AS.The patients were evaluated by the gradients across aotic valves i n pre- and post-PBAV and by echocardiogram during the follow-up period.Results Fifteen of 19 （78.9%）cases of typical AS had a better outcome and the gradien t of the remaining 4 cases (26.7%) had increased after follow-up (ΔP&gt;50 mm Hg).Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose.There was no moderate to s evere aortic insufficiency (AI). Conclusion The balloon aortic valvuloplasty provides safe and significant hemodynamic and c linical improvement in pediatric patients.The outcome of PBAV for typical AS is better than for hypoplastic AS.     

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.     

Emerging new frontiers in cardiac pacing: cardiac pacing in heart failure

Indications for pacing have leapt beyond sinus node dysfunction and atrioventricular (AV) block. Pacing for the purpose of improving hemodynamics has become the prime subject of exploration. Several studies have reported hemodynamic and clinical improvement with bi-ventricular pacing and AV sequential pacing. Data is still pouring in from the various ongoing trials regarding the beneficial effects of these methods of pacing. This is especially true in a subset of patients with intractable heart failure. There are several indicators to identify these patients. Those who have intra-ventricular conduction defects and those who demonstrate hemodynamic improvement after temporary pacing are certainly the candidates who will benefit most from this new form of pacing. Prolonged PR interval or left bundle branch block with intractable heart failure also falls into this category. The rationale of pacing in heart failure is to correct the cardiac dysynchrony that occurs frequently in these patients. Cardiac dysynchrony can occur due to ineffective synchronization between atria and ventricles (AV dysynchrony) or due to lack of synchronization within the two ventricles (ventricular dysynchrony). This is overcome by AV sequential pacing or by multi chamber pacing using the coronary sinus as portal of entry of the electrode into the cardiac vein to pace the left ventricle. Pacing leads and generators have been designed to suit the new found methods of pacing. Clinical trials are in full swing to establish the efficacy of these methods.     

房间隔与右心耳起搏对阻止新发房颤的探讨

选取66例病态窦房结综合征患者,均符合双腔起搏器适应证。随机分为两组,一组为右心耳(RAA)起搏36例,另一组为低位房间隔(LAS)起搏30例,随访12个月。 LAS组房颤发生率(3．3%)较 RAA(19．4%)组低;RAA 组 P 波离散度较 LAS 组明显增大(P <0．01);3个月后 RAA 组左心房容积指数(LAVI)较 LAS 组大。较之 RAA 组,LAS 组 P 波离散度降低、LAVI 减小,在阻止新发房颤方面可能更优。     

食管心房调搏在快速型心律失常诊断中的临床意义

目的探究食管心房调搏在快速型心律失常诊断中的临床意义。方法选择85例快速型心律失常病人作为研究对象,实行食管心房调搏检查,测定食管导联的R-P'E、P'E-R时限,比较V1导联的R-P'时限与食管导联的R-P'E时限,并与心脏电生理检查的结果作比较。结果经心脏电生理确诊后的分型:顺向型房室折返型心动过速（O-AVRT）57例,慢-快型房室结内折返性心动过速[AVNRT（S-F）]19例,房性心动过速1例,心房扑动1例,心房颤动2例,左心室特发性室速3例,冠状动脉窦无冠窦底起源的AT合并右房间隔部起源的心房扑动1例,左心房AT合并慢-快型房室结内折返性心动过速1例。经食管心房调搏检查发现AVNRT（S-F）型病人食管导联中R-P'E < P'E-R,且R-P'E < 70 ms;O-AVRT型病人大多R-P'E < P'E-R,且R-P'E>70 ms;右侧旁道型病人V1导联的R-P' < 食管导联R-P'E;左侧旁道型病人V1导联的R-P'>食管导联的R-P'E。经食管心房调搏终止,85例病人的快速型心律失常有效终止率为88%。结论食管心房调搏可以鉴别快速型心律失常的类型,尤其是其中阵发性室上性心动过速的分型,对后续治疗方案的合理制定、心脏电生理检查以及射频消融术均提供了帮助,且对快速型心律失常有较高的终止率。     

Optimization of atrioventricular delay by surface electrocardiography during dual chamber pacing

During dual chamber pacing, both atrial and ventricular leads are routinely positioned at the right appendage and right ventricular apex. Alterations in cardiac electromechanical direction and sequence may have an impact on left atrial and ventricular contraction and filling, leading to reduction in left ventricular (LV) pumping function due to abnormal atrioventricular (AV) delay.1 To achieve adequate cardiac output and haemody- namic advantages of the heart in dual chamber pacing,2 optimal …     

双腔起搏不同房室延迟对左室舒张功能的影响

目的探讨植入双腔起搏器（DDD）术后患者不同房室延迟（AVD）、不同起搏状态对左室舒张功能的影响。方法选择30例接受DDD心脏起搏器治疗的病窦综合征患者，术后随访时，通过程控调节患者的AVD，采用彩色多普勒超声心动图测量不同起搏状态下患者的Tei指数、早期二尖瓣减速时间（DT）与舒张早期运动速度，舒张晚期运动速度（Em／Am）等左室舒张功能指标，用免疫荧光法测定血浆B型利钠肽（BNP），并比较不同起搏状态下以上各指标的差异。结果部分起搏与全部起搏状态下的心脏彩超舒张功能指标及BNP比较差异有显著性（P〈0．01），全部下传与部分起搏状态下的心脏彩超舒张功能指标及BNP比较差异有显著性（P〈0．01）。结论全部下传状态下患者的左室舒张功能最佳，提示AVD的选择对植入DDD的病窦综合症病人有重要意义。     

食管心房调搏对心律平治疗室上性心动过速的急性电生理效应的研究

应用食管心房调搏术（ＴＥＡＰ）观察心律平对５０例阵发性室上性心动过速的急性电生理效应。结果表明：心律平对房室旁道和房室结双径道均有明显的抑制作用，以旁道尤为明显。该药能阻断旁道的前向和逆向传导，延长其不应期。并使房室结传导的文氏阻滞点和２：１阻滞点提前，从而有效终止心动过速的发作。     

低交感张力型窦房结功能障碍

目的 研究交感神经张力低下对窦房结功能的影响。方法 回顾性分析５２８例窦性心动过缓病人运动试验,阿托品试验、异丙肾试验、Ｈｏｌｔｅｒ监测、固有心率测定和经食道心房调搏资料。结果 ５２８例中,２２例（３．８９％）阿托品试验阴性,而运动及异丙肾试验阳性,固有心率实测值低于预测值,经食道心房调搏有不同程度的窦房结恢复时间和窦房传导时间延长。结论 病态窦房结综合征可由窦房结或其周围组织器质性损害所致,但亦     

DUAL ATRIOVENTRICULAR NODAL PATHWAYS ASSOCIATED WITH A NODOVENTRICULAR TRACT INSERTING INTO THE LEFT VENTRICLE A CASE REPORT

A patient with recurrent paroxysmal tachycardia of right bundle branch block morphology (RBBBM) and atrioventricular (AV) dissociation is demonstrat ed by electrophysiologic study to have dual AV nodaJ pathways and a unique left sided nodoventricular (NV) tract. Dual AV nodal pathway was manifest in three ways: sudden increment in AV nodal con duction in response to premature stimulation, dou ble ventricular responses to single atrial extrastimuli and alternating fast and slow pathway conduction during right atrial (RA) programmed stimulation or RA overdrive pacing. The A-H interval of the fast pathway was 180 msec and that of the s!ow pathway was 290-330 msec. During RA stimulation, conduc. tion over the slow pathway was associated with marked prolongation of AV conduction, decrease of the H-V interval (0-30 msec) and induction of a QRS morphology similar or identical to that recorded dur ing spontaneous tachycardia. Tachycardia could be initiated by RA stimulation when impulses were conducted over the slow pathway or by right ventri cuk:r stimulation. The variation of QRS duration from 90-125 msec in RBBBM tachycardia indicated that the reentry circuit was confined to the AV node using the slow pathway as the antegrade limb and the fast pathway as the retrograde Iimb and that the anomalous tract was a NV fiber rather than a fascicaloventricular fiber.     

静脉注射地尔硫对人心脏电生理的影响

目的:探讨静脉应用地尔硫卓艹对心脏电生理的影响。方法:38例阵发性室上性心动过速患者消融成功后的自愿者,静脉给予地尔硫卓艹,首剂0.2m g/kg静脉推注(稀释至10~15m l,5m in内推完),继续以1~5μg(kg.m in)维持滴注,30m in后开始测量相关数值。结果:心率减慢,房室结传导时间及有效不应期延长,心房及心室的有效不应期缩短均有统计学差异,心房内的传导时间(高右房起搏至希氏束A波的时间)及HV的传导时间不受影响,心房内的离散度无明显统计学差异。无一例在试验过程中出现窦性心动过缓、窦性停搏及房室传导阻滞发生。结论:静脉滴注地尔硫卓艹对心率、房室结的影响是有限的,对窦房结和房室结功能正常者应用是安全的。     

Effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony

Background Right ventricular apical pacing has been reported to reduce cardiac performance. But there are few reports on the effects of dual chamber (DDD) pacing on cardiac function compared to sinus rhythm. In this study, we evaluated the effects of right atrial and ventricular DDD pacing on cardiac function and ventricular contraction synchrony using equilibrium radionuclide angiography. Methods Ten patients implanted with a right atrial and ventricular DDD pacemaker underwent equilibrium radionuclide angiography. The scintigraphic data were obtained during sinus rhythm and pacing rhythm. Cardiac function parameters were obtained semimanually. Phase analysis was used to study the ventricular activation sequence and ventricular synchrony. Results The left ventricular 1/3 ejection fraction decreased significantly during pacing compared with that during sinus rhythm［(23.4±6.1)% vs (27.7±4.5)%, P=0.01］. Regional ejection fraction also decreased during pacing, although the difference was not statistically significant. Phase analysis showed that the right ventricle was activated earlier than the left ventricle during pacing, and that the phase shift was significantly greater during pacing than that during sinus rhythm［64.13°±16.80° vs 52.88°±9.26°, P=0.007］. The activation of both ventricles occurred simultaneously during sinus rhythm, with the activation sequence from proximal septum or base of left ventricle to apex. The earliest activation during pacing occurred at the right ventricular apex, and subsequently spread to the base and left ventricle.Conclusion Right atrial and ventricular DDD pacing impairs left ventricular systolic function and ventricular synchrony.     

经食道心房调搏术诊断房室结内双径路的标准

In order to assess the diagnostic methods of dual atrioventricular node pathway (DAVNP), we performed transesophageal atrial pacing in 58 patients with palpitation. These patients were classified into two groups, group A comprising 40 patients without broken A-V conduction curve during pacing, compared with group B of 18 patients with broken A-V conduction curve. In our study, both atypical Wenckebach cycle and 3:2 A-V conduction during the increment atrial pacing (IAP) had no significant difference between the two groups (P greater than 0.05). The maximum increments of SR interval in Wenckebach cycle of group A and B during pacing (Wenckebach delta SRmax) were 83.59 +/- 20.92 ms and 125.00 +/- 32.52 ms respectively (P less than 0.001) and at the cut-off point of Wenckebach delta SRmax at 120 ms the specificity and positive predicative value were very high (96.88% and 90.91%), but sensitivity was not so high (71.43%). The minimum increments of RS interval (delta RSmin) in a greater change of SR interval showed a significant difference between the two groups and the specificity and positive predicative value were also high, but the sensitivity was not so high, either (78.57%). We conclude that the diagnostic value of both Wenckebach delta SRmax and delta RSmin, when the SR interval is of greater change during pacing to the DAVNP, is rather significant. As the sensitivity is very low, isolated atypical Wenckebach phenomenon is not as reliable a diagnostic criterion to the DAVNP as previously supposed.     

窦房结功能障碍时的体表窦房结电图

对临床诊断的60例病窦,20例可疑病窦及60例单纯窦缓者检测体表窦房结电图,发现窦房结除起搏频率低于60次/min外,60例病窦中的57例,20例可疑病窦中的15例,窦房结有心电图不易发现的起搏或/和传导功能障碍。起搏功能障碍的表现为:起搏功能不稳定,时而起搏,时而停止,形成间歇性窦性停搏或窦房结与心房间游走心律;偶见窦性搏动或窦房结无起搏功能,完全由次级起搏点取代等。传导功能障碍的表现为:传导时间延长或窦房传导阻滞等。此结果表明体表窦房结电图在检测窦房结功能障碍方面具有独特的临床意义。     

117例经食道心房调搏临床分析

目的:探讨经食道心房调搏检查的临床应用价值。方法:回顾分析117例进行经食道心房调搏电生理检查的临床资料。结果:在行窦房结功能检查中81.5%患者(22例)为迷走神经张力过高导致的窦性心动过缓,18.5%(5例)患者为窦房结功能低下。14例阵发性室上性心动过速患者经食道调搏超速抑制法治疗均终止发作。结论:经食道心房调搏检查具有无创、安全、简便、有效的特点,适合在临床上推广应用。