食管心房调搏诱发与终止房室折返性心动过速的研究

目的探讨经食管心房调搏诱发与终止房室折返性心动过速的价值。方法选择255例有心动过速发作史,并且既往心电图证实有阵发性室上性心动过速(PSVT)的患者行食管心房调搏检查。结果在被检的255例患者中诱发房室折返性心动过速229例,占89.8%(其中顺向型217例,占94.8%,逆向型12例,占5.2%)。诱发成功的最佳刺激方法为程序期前刺激法(S1S2、S1S2S3),诱发率为88.2%。诱发的必备条件是旁路有效不应期长于房室结有效不应期。在诱发房室折返性心动过速的229例中215例经电刺激成功终止,转复为窦性心律,成功率为93.9%,其中64例采用短阵快速刺激一次性成功终止,转复成功率达100%。结论食管心房调搏能有效地诱发与终止房室折返性心动过速,诱发顺向型房室折返性心动过速的关键因素是旁路不应期大于房室结有效不应期,终止发作的最有效的刺激方法为短阵快速刺激。本法可作为急诊终止阵发性室上性心动过速的首选方法。     

逆向房室折返性心动过速的电生理特点

目的 探讨逆向房室折返性心动过速(antidromic atrioventricular reciprocating tachycardia,AAVRT)患者的电生理特点.方法 回顾性分析14例AAVRT患者的经食管心房调搏(transesophageal atrial pacing,TEAP)及心内电生理检查资料.结果 TEAP检查显示,14例AAVRT患者中有2例自行发作,6例基础刺激诱发,6例静脉滴注异丙肾上腺素后诱发:4例自行终止,6例超速刺激法终止,2例药物终止,2例短不应期旁道行超速刺激转为预激伴心房颤动.心内电生理检查显示,14例AAVRT患者中有5例(35.7%)双旁道,9例(64.2%)单旁道,其中2例(13.3%)合并房室结双径路.结论 AAVRT患者双旁道或多旁道发生率较高,偶见合并房室结双径路;AAVRT超速刺激终止时可诱发预激伴心房颤动.     

Kent型预激旁道有效不应期研究

对91例 Kent 型预激综合征进行以食管调搏早搏刺激程控扫描的方法测定其旁道有效不应期。91例中典型预激60例,隐性(潜在性)预激31例,两者旁道有效不应期无显著性差异(P>0.05),而房室结有效不应期则有显著性差异(P<0.05);有心动过速史者与无心动过速史者相比,旁道有效不应期有非常显著性差异(P<0.01)。在不同年龄组之间,无论是旁道的还是房室结的有效不应期均未发现有显著性差异。     

显性预激综合征与房室折返性心动过速100例分析

分析１００例显性预激综合征食管心房调搏的资料，结果表明：①诱发顺向型房室折返性心动过速（Ｏ－ＡＶＲＴ）４９例，左侧旁道（ＡＰ）较右侧ＡＰ发生率高；逆向型房室折返性心动过速（Ａ－ＡＶＲＴ）３例，均见于右侧ＡＰ。前向与逆向的单次折返１３例。房室折返性心律失常总计６５例，占６５％。②Ｏ－ＡＶＲＴ的形成应具备旁道前传的有效不应期（ＡＰＡ－ＥＲＰ）＞房室结有效不应期（ＡＶＮ－ＥＲＰ）＞左房有效不应期（ＬＡ－ＥＲＰ）。Ａ－ＡＶＲＴ的形成，应具备ＡＶＮ－ＥＲＰ＞ＡＰＡ－ＥＲＰ＞ＬＡ－ＥＲＰ。③房室折返性心动过速的诱发以Ｓ_１Ｓ_２及分级递增法为最佳。     

食管心房调搏诊断室上性心动过速的临床研究

为探讨食管心房调搏揭示室上性心动过速发生机制的价值和局限性,回顾性分析成功射频导管消融的１３８例隐匿性单房室旁道参与的顺向型房室折返性心动过速和１００例单一类型房室结折返性心动过速的食管心房调搏结果。结果显示：前１３８例中,３例前间隔旁道引起者食管心房调搏均诊断为房室结折返性心动过速余为左右侧其它部位的旁道,诊断正确。后１００例中,５例为慢－慢型,２例为快－慢型,食管心房调搏均诊断为房室折返性心动     

心律平治疗室上性心动过速的无创性电生理研究

本文采用经食管心房调搏方法观察了27例患者静脉注射心律平(1.5mg/Kg)前后的电生理变化。结果显示心律平对窦房结自律性和心室复极无影响;对房室传导、室内传导以及旁道逆行传导均有抑制作用;对心房、房室传导通道、房室结快通道以及旁道的前传有效不应期和房室传导文氏周长均有不同程度的延长作用。本文还观察到15例室上速用药后12例被终止,其中8例房室折返性心动过速均终止于折返环的逆行支。治疗有效的病例其持续性心动过速均不能再诱发。     

预激综合征与房室折返性心动过速

分析85例房室旁路有前传功能的预激征用食管心房调搏诱发正向型房室折返性心动过速的结果,发现诱发室上速的最重要因素是旁路不应期长于房室结不应期。基础心率的变化及静注阿托品,在部分病人可改变此二者的关系而增加诱发率。旁路不应期的长短、部位及预激的分型均无明显的影响。旁路逆向不应期过长或无逆传功能,是不能诱发室上速的重要因素。     

食管心房调搏诊断预激综合征宽QRS心动过速

用食管心房调搏结合多导同步描记术对33例预激综合征伴宽 QRS 心动过速进行电生理检查。提出了反向型房室折返性心动过速和正向型房室折返性心动过速伴束支传导障碍的食管调搏诊断标准。讨论了这些标准在诊断和鉴别诊断上的意义与局限性。     

顺向性房室折返性心动过速的诱发及终止方式

顺向性房室折返性心动过速（0AVRT）是阵发性室上性心动过速的常见类型。心动过速的诱发和终止与刺激部位、房室传导系统和房室旁道的不应期、传导速度等因素密切相关。了解其诱发与终止方式是预激综合征电生理检查的内容之一，既可了解心动过速的形成机制、电生理特征，又对体表心电图明确诊断有较大帮助。     

房室结／隐匿性旁道折返性心动过速食管调搏诊断指标的评价

为提高食管调搏对折返性心动过速的诊断准确率,对30例房室结折返性心动过速和35例隐匿性旁道折返性心动过速作食管调搏(该65例诊断结果与射频消蚀诊断一致率为98.5%).结果显示:电刺激重复诱发和终止以及心动过速时R-P/P-R<1诊断两型的必备指标;室上速第1个P-R间期<240ms、房室结双径路、R-P间期<70ms或>95ms、P_(v_1)-P_E时距≥25ms、P与QRS重叠、QRS后逆行P等是鉴别两型的综合指标.认为食管调搏多指标综合分析对诊断两型折返性心动过速及指导治疗有重要意义.     

Physiological cardiac pacing: Current status

Adverse hemodynamics of right ventricular (RV) pacing is a well-known fact. It was believed to be the result of atrio-ventricular (AV) dyssynchrony and sequential pacing of the atrium and ventricle may solve these problems. However, despite maintenance of AV synchrony, the dual chamber pacemakers in different trials have failed to show its superiority over single chamber RV apical pacing in terms of death, progression of heart failure, and atrial fibrillation (AF). As a consequence, investigators searched for alternate pacing sites with a more physiological activation pattern and better hemodynamics. Direct His bundle pacing and Para-Hisian pacing are the most physiological ventricular pacing sites. But, this is technically difficult. Ventricular septal pacing compared to apical pacing results in a shorter electrical activation delay and consequently less mechanical dyssynchrony. But, the study results are heterogeneous. Selective site atria pacing (atrial septal) is useful for patients with atrial conduction disorders in prevention of AF.     

Permanent HIS bundle Pacing Feasibility in Routine Clinical Practice: Experience from an Indian Center

There is a paucity of experience regarding His bundle pacing (HBP) at laboratories initially attempting the procedure, especially in the Indian scenario. Patient who underwent HBP were selected for pacing therapy or in lieu of cardiac resynchronization therapy (CRT) at a single center. Among 22 patients attempted, 19 patients underwent successful implant, achieving selective HBP in 14 patients. There was a significant improvement in left ventricular ejection fraction (LVEF) (49.3 ± 9.3 vs. 36.7 ± 9.2) in the LV dysfunction subgroup (n = 6). Over a follow-up of 15 ± 6.5 months, thresholds were stable in all except one patient, and there was no requirement of lead revision. In summary, we found that HBP is a feasible option for achieving physiological pacing.     

三极起搏法及其在经食管心房起搏术中的应用价值

为克服现行经食管心房起搏术中常见缺点,作者试用三极起搏法。实验表明:就降低起搏阈值、减小脉冲幅度而沦,三极起搏法显著低于常规二极起搏法;以减轻受检者痛苦,保持起搏稳定为目的,三极起搏法中双正极法明显优于双负极法。双正极法还有图形整洁、起搏P波清晰、方法尤为简便等优点,在经食管心房起搏检查中有其一定的实用价值。     

A feasible approach for direct his-bundle pacing using a new steerable catheter to facilitate precise lead placement

INTRODUCTION: Much clinical evidence has shown that right ventricular (RV) apical pacing is detrimental to left ventricular function. Preservation of the use of the His-Purkinje (H-P) system may be ideal in heart block that is restricted to the AV node, but may be of no benefit when H-P disease exists. AIM: To investigate the feasibility of direct His-bundle pacing (DHBP) using a new system consisting of a steerable catheter and a new 4.1 F screw-in lead. METHOD: Between May and December 2004, 26 patients (19 male, mean age: 77 +/- 5 years) with a standard pacemaker (PM) indication and preserved His-bundle conduction were enrolled and DHBP was attempted. RESULTS: DHBP was achieved in 24 patients (92%); two patients were paced in the His area, but the paced QRS morphology and duration were different from the native QRS. The mean time for lead positioning was 19 +/- 17 minutes, the mean fluoroscopy time was 11 +/- 8 minutes, and the total procedure time (skin-to-skin including positioning of a quadripolar diagnostic catheter for His recording) was 75 +/- 18 minutes. In DHBP pacing, the acute pacing threshold was 2.3 +/- 1.0 V at a pulse duration of 0.5 msec, and the sensed potentials were 2.9 +/- 2.0 mV. At a 3-month follow-up examination, the same QRS duration and morphology recorded on implantation were observed in all patients. The pacing threshold was 2.8 +/- 1.4 V, and sensed potentials were 2.5 +/- 1.8 mV; the sensing configuration was changed from bipolar to unipolar in 6 patients to resolve undersensing issues. No major complications were observed. CONCLUSIONS: This feasibility study shows that DHBP can be accomplished with a new system consisting of a steerable catheter and an active fixation lead in 92% of the patients in whom it was attempted.     

希浦系统起搏操作和临床分析:单中心经验

目的总结北京大学第一医院前50例希浦系统起搏病例,为初期开展此项技术提供临床借鉴。方法回顾性分析2019年4-12月本中心同一术者团队行希浦系统起搏操作的前50例患者资料及手术和随访情况。按起搏部位分为希氏束起搏(HBP)组、左束支区域起搏(LBBP)组、室间隔内起搏(IVSP)组,比较各组间的手术操作、起搏结果和参数随访情况。结果按患者手术先后顺序每10例患者一组,共分为5组。随着手术例数的增加,希浦系统起搏的成功率从前10例的50%上升至最后10例的90%,而手术时间显著缩短[(152.7±55.1)min比(89.8±37.7)min,P=0.037],完成20例手术后,成功率稳定在80%以上较好的水平。按照最终起搏的结果,IVSP组15例、HBP组10例、LBBP组25例。左心室激动时间(LVAT),HBP组[(79.4±8.2)ms比(96.0±19.2)ms,P=0.012]和LBBP组[(81.5±13.5)ms比(96.0±19.2)ms,P=0.013]均显著短于IVSP组,差异均有统计学意义;而HBP组和LBBP组[(79.4±8.2)ms比(81.5±13.5)ms,P=0.928]比较,差异无统计学意义。起搏QRS波时限,HBP组[(106.4±19.9)ms比(138.8±18.9)ms,P<0.001]和LBBP组[(118.9±12.3)ms比(138.8±18.9)ms,P<0.001]均显著短于IVSP组,差异均有统计学意义;LBBP组较HBP组延长[(118.9±12.3)ms比(106.4±19.9)ms,P=0.030],差异有统计学意义。但HBP组的起搏阈值显著高于IVSP组[(1.4±0.5)V比(0.6±0.3)V,P<0.001]和LBBP组[(1.4±0.5)V比(0.7±0.2)V,P=0.019],差异均有统计学意义。感知R波则HBP组显著低于IVSP组[(5.7±2.1)mV比(10.2±5.3)mV,P=0.009]和LBBP组[(5.7±2.1)mV比(9.6±2.2)mV,P<0.001]。而LBBP组和IVSP组各项起搏参数均无差异。各组随访期间,起搏阈值和感知R波均无明显变化。手术操作中我们采用了影像法辅助希氏束及左束支区域的解剖定位。结论本中心回顾分析显示,第20~50例的手术操作,可以较熟练掌握希浦系统起搏技术。LBBP可作为初期开展希浦系统起搏的首选。影像解剖定位法可简化手术流程,避免对希氏束和传导束的损伤。     

Mortality and Incidence of Atrial Fibrillation in Paced Patients

Mortality and AF Incidence in Paced Patients. This review presents and discusses available data from randomized controlled trials on the prognosis of pacemaker patients, especially the incidences of atrial fibrillation (AF) and death, the impact of pacing mode selection, and the impact of AF on prognosis. The incidence of AF is several times higher in paced patients than in the nonpaced population. The annual incidences of AF and chronic AF are at least 5% and 3%, respectively, after pacemaker implantation. Mean lifetime cumulative incidences of AF and chronic AF can be estimated at approximately 30% to 40% and 20%, respectively. The most important predictors of AF are brady‐tachy syndrome, sick sinus syndrome, and selection of VVI(R) pacing mode. The expected lifespan in paced patients is shorter than in the age‐matched nonpaced population. One of the factors decreasing lifespan in paced patients most likely is the high incidence and prevalence of AF. In patients with sick sinus syndrome, VVI pacing significantly increases AF and mortality compared with AAI pacing. In a mixed population of patients with bradycardia, DDD(R) pacing causes AF less often than does VVI(R) pacing. Survival does not differ between these pacing modes within the first 3.5 years after pacemaker implantation. At the present time, AAI(R) should be the preferred pacing mode in patients with sick sinus syndrome, and DDD(R) should be used for other patients without chronic AF for prevention of AF. It is not clear whether prevention of AF will improve survival of paced patients.     

The Atrial Pacing Peri-ablation for Paroxysmal Atrial Fibrillation (PA3) Study: rationale and study design.

The Canadian Atrial Pacing Peri-Ablation for Paroxysmal Atrial Fibrillation Study tested the hypotheses that atrial pacing prevents paroxysmal atrial fibrillation (PAF) in patients without symptomatic bradycardia and that DDDR pacing is more likely to prevent PAF following total atrioventricular (AV) node ablation compared to VDD pacing. Patients with PAF who were refractory to or intolerant of antiarrhythmic drug therapy received a Medtronic Thera DR pacemaker 3 months prior to a planned total AV node ablation. Patients were randomized to atrial pacing or no pacing therapy. The time to first recurrence of sustained PAF was the primary study outcome event. Following AV node ablation, patients were randomized to the DDDR or VDD mode in a crossover study design. Patients were followed in each mode for 6 months. The time course of PAF recurrence was compared for each pacing mode.