Beneficial biventricular pacing in a patient with cardiac sarcoidosis and refractory heart failure: a case report

A 54-year-old woman had been treated under a diagnosis of cardiac sarcoidosis since 1998. She was admitted to our department because of recurrent heart failure in April 2002. A DDD pacemaker was implanted because of complete AV block in 2000, but she had always suffered from > or = New York Heart Association (NYHA) class III heart failure. To prevent recurrent heart failure, biventricular pacing was performed. The left ventricular epicardial pacing lead was newly inserted into the great cardiac vein via the left subclavian vein, and connected with the previously implanted generator. The QRS duration decreased from 200 to 140 msec. Serum brian natriuretic peptide level decreased from 321 to 226 pg/ml. Cardiac index increased from 1.93 to 2.20. Her functional class improved from NYHA class III to class II.     

床旁经左锁骨下静脉临时心脏起搏治疗急性心肌梗死心律失常

目的：探讨床旁经左锁骨下静脉临时心脏起搏治疗急性心肌梗死合并缓慢性心律失常患者的疗效与安全性。方法：在无X线透视下,为38例急性心肌梗死患者经左锁骨下静脉路径床旁安置临时心脏起搏器。结果：37例穿刺左锁骨下静脉送入临时电极成功,即刻起搏成功率97．3％,手术开始至起搏成功时间8．0±2．2min,电极导管留置时间1～21d,其中2例电极导管脱位。31例急性心肌梗死经临时起搏后,心肌供血得到改善,恢复自主心律,顺利渡过超急期,1例过渡到安置埋藏式心脏起搏器。结论：床旁经左锁骨下静脉安置临时心脏起搏器成功率高,快速,能改善急性心肌梗死并发严重缓慢心律引起的血流动力学变化,适合于临床推广应用。     

床旁紧急临时心脏起搏262例分析

目的:评估床旁临时心脏起搏器安置术救治急危重患者心脏急症的可行性和有效性,分析不同静脉途径及电极导管的利弊。方法: 对262例伴发多种类型心律失常的患者在动态心电监测下采用床旁经静脉穿刺法行心脏临时起搏器安置术,入管路径依次为右侧颈内静脉136例次、双侧锁骨下静脉108例次、右侧股静脉18例次。评估临床可操作性、单次穿刺成功率、起搏成功率、术中及术后并发症等。结果: 254例次经床旁盲插导管成功起搏,成功率97.0%。4例在数字减影血管造影（DSA）引导下成功起搏,4例起搏失败。平均操作时间2～12 min。起搏器安置术中、起搏应用过程中共发生室速、血气胸、导管脱落、感知起搏不良等相关并发症27例,占10.3%。无室颤、心急穿孔等严重并发症。结论: 床旁临时心脏起搏术在心脏急危重患者特别是急性缓慢性心律失常的救治中具有快捷、损伤小、灵活性高、疗效好、并发症少等特点,特别是右侧颈内静脉路径及球囊漂浮起搏导管在危重症患者的综合救治中优势明显。     

Advances in Cardiac Pacing: Beyond the Transvenous Right Ventricular Apical Lead

While for decades right ventricular (RV) apical pacing has been the standard of care for patients requiring pacemaker or defibrillator lead placement, investigators have sought alternatives to achieve more physiologic electrical activation of the heart and reduce long‐term pathologic effects of nonphysiologic apical pacing. These investigations have included attempts at identifying superior pacing sites within the right atrium and RV and development of new leads to enhance specificity of sensing and capture. This review focuses on recent advances in alternative sites for pacing and developments in novel pacing technology ranging from intramyocardial electrodes to leadless pacemakers. First, there have been several studies demonstrating potential benefits of site‐specific pacing, including His bundle pacing and RV outflow tract pacing in potentially attenuating electromechanical dyssynchrony and long‐term functional decline seen with RV apical pacing. Available options for lead placement have been enhanced by development of intramyocardial electrodes that may significantly reduce far‐field oversensing and nonchamber specific capture. With development of intramyocardial electrodes, the potential for atrioventricular septal pacing has recently been described, making synchronous activation of both ventricles with a one‐lead system possible without crossing the tricuspid valve and offering an alternative to modern cardiac resynchronization therapy (CRT). Finally, recent advances in leadless pacemaker systems using ultrasound or magnetic fields are briefly discussed. The results of these studies suggest that there may be options to the RV apex, made possible by novel lead and pacemaker technology. These advances can potentially aid in reducing long‐term negative effects of chronic pacemaker therapy.     

Leadless cardiac ventricular pacing using helix fixation: Step-by-step guide to implantation

Introduction

Leadless cardiac pacemakers are an alternative modality to traditional transvenous pacemaker systems. Recently receiving Food and Drug Administration approval, the AVEIR VR leadless pacemaker system provides a helix based active fixation leadless pacemaker system. This step-by-step review will cover patient selection, preprocedural planning, device implantation technique, implant site evaluation, troubleshooting, short- and long-term complications as well as future directions for leadless pacing.

Methods

We collected and reviewed cases from primary operators to provide a step-by-step review for implanters.

Results

Our paper provides a guide to patient selection, pre-procedural planning, device im plantation technique, implant site evaluation, troubleshooting, short- and long-term complications as well as future directions for leadless pacing.

Conclusion

The helix based active fixation leadless pacemaker system is a safe and efficacious way to provide pacing support to patients and provides an alternative to transvenous pacing systems. Our review provides a step-by-step guide to implantation.     

First case report in Japan of left ventricular pacing via a coronary vein in a patient with a mechanical tricuspid valve

Transvenous endocardial pacemaker implantation is contraindicated in patients after prosthetic tricuspid valve replacement. A 65-year-old woman underwent both replacement of the mitral and tricuspid valves and pacemaker implantation with epicardial lead for bradycardia with chronic atrial fibrillation. At 2 years after this operation, the pacemaker's battery became low, and she was admitted for a battery exchange. To avoid frequent battery exchanges because of high stimulation thresholds, a left ventricular pacing lead was implanted via a coronary vein. There were no complications and the stimulation thresholds were stable. Coronary vein leads enable a minimally invasive approach, improve safety, and give effective stimulation for patients with a prosthetic tricuspid valve. This is the first case report in Japan of left ventricular pacing in such a patient.     

Effects of electrocautery on the threshold values of permanent pacing. An experimental study]

One of the hazards of high frequency electrical interference (electrocautery) with cardiac pacing is thought to be related to an increase in the threshold values leading to loss of pacing. This hypothesis was examined in an experimental study performed on 5 dogs. A pacing catheter was introduced via the right jugular vein and positioned at the apex of the right ventricle and connected successively to several stimulators implanted in a latero-cervical subcutaneous pocket. A Bovie 400 CT generator was used to deliver a high frequency 1.75 MHz current between a probe applied near to the pacemaker pocket and an electrode placed under the right leg. One or two 5 second bursts were applied for each make of pacemaker, making a total of 3 to 6 applications per animal. A detecting circuit enabled the measurement of the currents in the catheter during the application. The thresholds of pacing were measured before and after each manipulation for several pacing impulse durations. At the maximal output of the generator, the highest recorded current was 117 mA (modulated) and 141 mA (unmodulated). The thresholds of stimulation did not change significantly and the pacing catheter impedance was also stable. This study suggests that high frequency current does not modify the threshold of stimulation in cardiac pacemaker patients. The loss of pacing sometimes observed after the use of electrocautery is probably related to pacemaker dysfunction.     

Mediastinal thymoma invading the superior vena cava and the right atrium

An 86-year-old male patient presented with a large mediastinal tumor. A needle biopsy was performed and revealed a diagnosis of invasive thymoma. Multidetector computed tomography (MDCT) angiography was performed in order to assess operability of the tumor. This showed a heterogeneously enhancing anterior mediastinal mass. The tumor had invaded the left brachiocephalic vein, presumably via the inferior thymic veins, which is a known feature of these tumors. The thymoma grew then endovenously through the superior vena cava into the right atrium. A pacemaker lead was completely encased by tumor tissue. The patient was deemed inoperable and underwent radiation therapy.     

Symptomatic unilateral cannon "a" waves in a patient with a ventricular pacemaker.

A 64-year-old woman was referred because of intermittent pulsations of the left side of the neck, face, and scalp that were first noticed after the insertion of a ventricular pacemaker. The pacemaker had been inserted because of symptomatic 2:1 atrioventricular block. Right cardiac catherization showed cannon "a" waves, and phlebographic studies revealed stenosis of the right innominate and internal jugular veins. The symptoms were abolished by conversion to an atrial synchronous pacing system. Comments are offered on the hemodynamic findings, the "pacemaking syndrome", and the use of atrial synchronous pacing.     

超声心动图引导下安装临时心脏起搏器的应用

目的 对比观察在超声心动图与放射线引导下安装临时心脏起搏器的效果和安全性.方法 将需要安装临时心脏起搏器的50例患者按先后顺序分为两组,超声引导下安装临时心脏起搏器（超声组）25例,经右颈内或右锁骨下静脉插入起搏电极导管;放射线下安装临时心脏起搏器（放射组）25例,经股静脉插入起搏电极导管.结果 两组临床特征相似,超声组从穿刺到开始起搏时间比放射组短,差异有统计学意义[（521±180）s vs.（750±226）s,P＜0.001].超声组重置电极导管患者比例明显少于放射组,差异有统计学意义[8％（2/25） vs.40％（10/25）,P＜0.001].超声组起搏功能失常的发生率低于放射组,差异有统计学意义[8％（2/25）vs.32％（8/25）,P=0.001].超声组未发生心脏穿孔和起搏导管周围静脉血栓,放射组分别发生1例和2例.结论 在超声心动图引导下安装临时心脏起搏器操作方法简便、安全、有效,是一种较好的方法,可准确放置起搏电极导管.     

Pacemaker-induced cardiovascular failure. Hemodynamic and angiographic observations

A 71 year old woman underwent permanent transvenous right ventricular pacemaker implantation for prolonged syncope and atrioventricular conduction defects. Each time the patient's heart rate spontaneously decreased to less than 70 beats/min, cardiovascular collapse with hypotension and reduced cardiac output occurred. Left ventricular cineangiography performed during both sinus rhythm and right ventricular pacing demonstrated reduced left ventricular end-diastolic volume, secondary to a loss of atrial contribution to left ventricular filling, and severe, acute mitral regurgitation with significantly decreased effective stroke volume and cardiac output. Pacing from the left ventricular endocardium had the same effect. The detrimental effects of cardiac pacing necessitated removal of the right ventricular pacemaker.     

床旁经左锁骨下静脉临时心脏起搏治疗缓慢性心律失常的临床应用

目的探讨床旁经左锁骨下静脉临时心脏起搏治疗缓慢性心律失常的疗效与安全性。方法在无X线透视下,为63例缓慢性心律失常患者经左锁骨下静脉路径床旁放置临时心脏起搏器,记录起搏效果、操作时间、电极放置部位等指标。结果 63例患者均穿刺左锁骨下静脉送入临时电极成功,即刻起搏成功率100%,起搏阐值为（1.95±0.12）V,操作时间（7.3±0.37）min,起搏电极放置位置：右心室尖部起搏9例（14.3%,9/63）,右室流出道起搏53例（84.1%,53/63）,冠状静脉窦内起搏1例（1.6%,1/63）。无穿刺失败及其他并发症。结论床旁经左锁骨下静脉临时心脏起搏术操作简便、起搏效果好,适合紧急临时心脏起搏患者使用。     

Clinical application of temporary pacemaker insertion guided by bedside ultrasound in elder and critical patients

Background Ultrasound-guided temporary pacemaker implantation has been proven safe and efficient. However, few studies have focused on elder and critical patients. Methods Twelve elder and critical patients underwent temporary cardiac pacing through the jugular vein or subclavian vein, with bedside ultrasound images to assist the placement of electrode within the right ventricle. Results Ultrasound-guided temporary cardiac pacemaker insertion was successful in all of the 12 patients. Electrodes were sent into the right ventricle correctly with the help of ultrasound imaging. In all cases, temporary pacemaker functioned well without procedure-related complications. Conclusion Temporary cardiac pacing guided by ultrasound is safe and effective in elder and critical patients, which is worth of promoting, especially in intensive care unit.     

Atrio-ventricular synchronous pacing with a single chamber leadless pacemaker: Programming and trouble shooting for common clinical scenarios

Micra leadless pacemaker has progressed from a single chamber pacemaker that can deliver VVIR pacing to a pacing device that can provide atrio-ventricular (AV) synchrony via a unique pacing algorithm that relies on identifying mechanical atrial contraction. This novel algorithm has its own limitations and intricacies. In this paper, we review this algorithm, suggest steps for troubleshooting and programming these devices and provide clinical examples of Micra AV cases that required changes in programming for adequate tracking of atrial activity.     

Persistent left-sided superior vena cava--a pacing challenge

A left sided superior vena cava (LSVC) occurs in 0.3% of the population. LSVC normally drains into the right atrium through a dilated coronary sinus. We illustrate two cases of dual chamber permanent pacemaker implantation by using (1) left subclavian vein in a 35-year-old woman with symptomatic Mobitz type II atrioventricular block; and (2) right subclavian vein in a 64-year-old man who was hospitalized with bradycardia, complete heart block, and alternating bundle branch block. After accessing the subclavian vein, the pacing leads were advanced into the LSVC, which was situated to the left of the vertebral column in the mediastinum. The leads followed the course of the LSVC medially before entering into the right atrium. Once inside the right atrium, the ventricular lead made a U-turn towards the tricuspid valve and into the right ventricle by shaping the stylet, and it was helped by right atrial contraction. An active fixation atrial lead was used in both cases to secure a satisfactory location within the right atrium. A small volume of contrast can be injected into the pacing sheath to visualize the coronary sinus opening into the right atrium, and the right ventricle. Fluoroscopy in oblique views can be helpful in guiding the atrial lead into the anteriorly positioned atrial appendage. In emergency transvenous ventricular temporary pacing where the subclavian or internal jugular vein is used, it is important to recognize the presence of a LSVC. The lead should first be directed into the right atrium and then looped back into the right ventricle. Excessive force must be avoided to prevent cardiac perforation and tamponade. If this is not successful, access through a femoral vein should be attempted.     

Successful implantation of leadless pacemaker in a patient with giant right atrium and tricuspid valve stenosis

With the steadily increasing amount of leadless pacemaker implantations performed worldwide, it has called attention to the delivery difficulty in patients with severe large right heart. Nevertheless, limited studies have reported leadless pacemaker implantation in patients with tricuspid stenosis. Here, we report the successful implantation of leadless pacemaker in a 60‐year‐old female patient with giant right atrium and tricuspid valve stenosis. It is highlighted that leadless pacemaker should not be discouraged even if there are tricuspid valve stenosis and giant right atrium.     

采用普通电极床旁心脏临时起搏疗效观察

目的探讨普通电极床旁紧急心脏临时起搏的可行性并评价其临床疗效。方法采用普通电极床旁紧急心脏临时起搏患者共34例,其中经右颈内静脉途径22例,左锁骨下静脉途径12例。根据体表起搏心电图形态及起搏阈值判断右室心内膜起搏是否成功。结果全组34例患者右心室心内膜起搏均获成功。2例患者术后24h发生电极移位。无气胸、血胸、心脏穿孔及感染等严重并发症。结论经右颈内静脉及左锁骨下静脉途径,应用普通电极床旁紧急心脏临时起搏安全有效。     

Persistent left‐sided superior vena cava – a pacing challenge

A left sided superior vena cava (LSVC) occurs in 0.3% of the population. LSVC normally drains into the right atrium through a dilated coronary sinus. We illustrate two cases of dual chamber permanent pacemaker implantation by using (1) left subclavian vein in a 35‐year‐old woman with symptomatic Mobitz type II atrioventricular block; and (2) right subclavian vein in a 64‐year‐old man who was hospitalized with bradycardia, complete heart block, and alternating bundle branch block.

After accessing the subclavian vein, the pacing leads were advanced into the LSVC, which was situated to the left of the vertebral column in the mediastinum. The leads followed the course of the LSVC medially before entering into the right atrium. Once inside the right atrium, the ventricular lead made a U‐turn towards the tricuspid valve and into the right ventricle by shaping the stylet, and it was helped by right atrial contraction. An active fixation atrial lead was used in both cases to secure a satisfactory location within the right atrium. A small volume of contrast can be injected into the pacing sheath to visualize the coronary sinus opening into the right atrium, and the right ventricle. Fluoroscopy in oblique views can be helpful in guiding the atrial lead into the anteriorly positioned atrial appendage.

In emergency transvenous ventricular temporary pacing where the subclavian or internal jugular vein is used, it is important to recognize the presence of a LSVC. The lead should first be directed into the right atrium and then looped back into the right ventricle. Excessive force must be avoided to prevent cardiac perforation and tamponade. If this is not successful, access through a femoral vein should be attempted.     

15例植入型起搏系统作临时起搏的临床应用

目的 探讨利用植入型起搏系统脉冲发生器外置作为临时起搏临床应用的可行性.方法 15例房室阻滞或窦性心动过缓需行临时起搏患者,经锁骨下静脉径路植入永久起搏系统的心室主动导线,头端固定于右心室间隔部,连接外置脉冲发生器,行临时起搏.结果 15例患者均顺利完成临时起搏过程.结论 植入型起搏系统脉冲发生器外置可作为临时起搏应用.     

Inadvertent permanent ventricular pacing from the coronary vein: an electrocardiographic, roentgenographic, and echocardiographic assessment

The incidence of inadvertent permanent ventricular pacing from the coronary vein is not known. In a retrospective analysis of 69 patients in whom transvenous pacemakers were implanted between 1979 and 1986, 12 patients were discovered to have right bundle-branch block pattern to the paced complexes on electrocardiogram. In this group, three patients were considered to have inadvertent placement of pacing lead in the coronary vein by two-dimensional echocardiographic criteria. No complications were noted in follow-up of 2-79 months. Monitoring of surface electrocardiogram, frontal and lateral fluoroscopy, and pacing threshold and sensing parameters (during implantation of pacemaker) were found to offer no absolute protection against malplacement of the lead. Placement of the lead into the lung field via the main pulmonary artery and then withdrawing with eventual positioning into the right ventricular apex will avoid malposition into the coronary vein. Two-dimensional echocardiography is useful for the diagnosis of pacing lead malplacement and should be performed in any patient with right bundle-branch block pattern in the surface electrocardiogram following pacemaker implantation.