模拟野战条件，自主研制介入方舱内临时起搏实验

目的：研究模拟野战条件下在自主创新研制介入方舱内行,临时起搏实验的可行性和时效性。方法：对5例正常狗在微创介入方舱内使用普通电极导管进行急诊心脏临时起搏模拟操作,观察该过程的时间,和操作效果,以及舱内人员的配合。结果：应用普通电极导管急诊心脏超速起搏5例全部成功,股静脉穿刺,无穿刺部位血肿、感染,血栓栓塞,心脏穿孔等并发症发生。时间在10分钟以内。结论：依托微创介入方舱,在野外恶劣条件下进行临时起搏的急救过程安全,实用,快捷。可用于战时以及非战争卫勤急救任务中,发挥重要作用。     

模拟野战条件，自主研制介入方舱内临时起搏实验

目的:研究模拟野战条件下在自主创新研制介入方舱内行临时起搏实验的可行性和时效性。方法:对5例正常狗在微创介入方舱内使用普通电极导管进行急诊心脏临时起搏模拟操作,观察该过程的时间,和操作效果,以及舱内人员的配合。结果:应用普通电极导管急诊心脏超速起搏5例全部成功,股静脉穿刺,无穿刺部位血肿、感染,血栓栓塞,心脏穿孔等并发症发生。时间在10分钟以内。结论:依托微创介入方舱,在野外恶劣条件下进行临时起搏的急救过程安全,实用,快捷。可用于战时以及非战争卫勤急救任务中,发挥重要作用。     

急性下壁心肌梗死急诊PCI术中应用临时起搏器与阿托品的对比研究

目的：探讨临时起搏器与阿托品在急性下壁心肌梗死急诊经皮冠状动脉介入治疗（PCI）中应用的疗效。方法：入选2012 年2 月至2013 年8 月我院收治的发病12 小时内,诊断为急性下壁心肌梗死并接受急诊PCI治疗的患者92 例,依据治疗方法的不同 将病例分为临时起搏组和阿托品组,并对病例进行为期一年的追踪随访,收集患者平均住院天数、平均住院费用、再灌注心律失 常、心肌梗死后心绞痛、心肌梗死后心衰发生率资料。结果：临时起搏组的平均住院天数、平均住院费用、心肌梗死后心绞痛、心肌 梗死后心衰发生率均显著低于阿托品治疗组（P 均<0.05）,阿托品治疗组的再灌注心律失常发生率则明显低于临时起搏组（P<0. 05）。结论：急性下壁心肌梗死急诊PCI中应用临时起搏器,具有治疗成本低,降低心血管事件发生率的优点,而阿托品治疗在改 善再灌注心律失常的疗效上则显著优于临时起搏治疗。     

临时起搏器经皮冠状动脉介入术治疗高风险冠状动脉病变的效果观察

目的分析并总结采用临时起搏器在实施经皮冠状动脉介入术治疗高风险冠状动脉病变中的应用效果。方法回顾性分析在临时起搏器支持下实施PCI的18例高危病人的临床资料,分析临时起搏器置入以及冠脉介入的操作情况。结果本组病人置入临时起搏电极起搏成功率达到100％。结论联合应用临时起搏器与经皮冠脉介入术治疗急性心肌梗死（AMI）与慢性血管闭塞性病变患者,能够降低经皮冠脉介入术治疗中由于严重心律失常导致的血液动力学改变,使病人尽快恢复正常心率以及各主要脏器的供血,减少患者的病死率,具有较高的安全性,值得在临床上广泛推广应用。     

Permanent pacemaker malfunction: diagnostic aspects of temporary pacing.

A temporary pacing electrode can function as a diagnostic as well as a therapeutic tool. This is illustrated in two patients whose permanent pacemakers unexpectedly failed. In the first patient a demand pacemaker was inhibited by a magnet rather than converting to the asynchronous mode. In the second the pacemaker appeared to be producing low-voltage potentials not detectable on the surface electrocardiogram. The presence of a temporary pacing electrode can be useful for defining the cause of pacemaker failure and the nature of any associated arrhythmias.     

Relationship between seasonal weather changes,risk of dehydration,and incidence of severe bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population

There is little information on any seasonal variations or meteorological factors associated with symptomatic bradyarrhythmias requiring cardiac pacing. The aim of this single-center study was to investigate the seasonal distribution of the incidence of severe, life-threatening bradyarrhythmias requiring urgent temporary transvenous cardiac pacing in an elderly population. Consecutive patients who underwent urgent temporary transvenous cardiac pacing between 2007 and 2012 were enrolled. The baseline characteristics of the patients and some meteorological parameters, including the calculation the daily heat index (HI), were recorded. During the study period, 79 consecutive patients (mean age 82?±?8 years, 41 % male) underwent urgent temporary transvenous cardiac pacing, mainly for third-degree atrioventricular block (79 %). The incidence of bradyarrhythmias was significantly higher in summer than in the other seasons (P??90 °F for >3 h per day for at least 10 days (P?P?P?P?相似文献   

Prevention of Hemodynamic Instability in Extra-Cranial Carotid Angioplasty and Stenting Using Temporary Transvenous Cardiac Pacemaker

Hemodynamic instability is a common condition during extra-cranial carotid angioplasty and stenting (CAS). We evaluated the safety and efficacy of prophylactic placement of temporary cardiac pacemaker during extra-cranial CAS for the prevention of hemodynamic instability. For this, forty-seven carotid artery stents were deployed in 41 high-risk patients. Temporary transvenous cardiac pacemakers were inserted before CAS procedure. The pacers were set to capture a heart rate <60 bpm. Clinical symptoms, blood pressure, heart rate, and pacing activation were monitored and data were collected. We found that pacing occurred in 25 carotid lesions during balloon predilatation; pacemakers were activated transiently in 25 patients. The longest pacing continued for 1 day. Among cases with pacemaker activation, 1 patient developed post-procedural symptomatic hypotension that lasted for 4 days. No related complications were observed. It was, therefore, concluded that pacing was technically effective in producing electrical ventricular responses and was hemodynamically effective in 25 carotid lesions which underwent balloon predilatation. The prophylactic use of a temporary transvenous cardiac pacemaker during CAS was rapid and effective in controlling peri-operative hemodynamic instability and preventing stroke and other complications. The prophylactic use of temporary pacemaker is particularly recommended for patients at high risk for developing hemodynamic instability.     

A comprehensive scoping review on transvenous temporary pacing therapy

Netherlands Heart Journal - Transvenous temporary cardiac pacing therapy (TV-TP) is widely used to treat life-threatening arrhythmias. Yet aggregated evidence on TV-TP is limited. We conducted...     

Adverse effects of atrioventricular synchronous right ventricular pacing on left ventricular sympathetic activity, efficiency, and hemodynamic status

Right ventricular (RV) pacing is now recognized to play a role in the development of heart failure in patients with and without underlying left ventricular (LV) dysfunction. We used the cardiac norepinephrine spillover method to test the hypothesis that RV pacing is associated with cardiac sympathetic activation. We studied 8 patients with normal LV function using temporary right atrial and ventricular pacing wires. All measurements were carried out during a fixed atrial pacing rate. The radiotracer norepinephrine spillover technique was employed to measure total body and cardiac sympathetic activity while changes in LV performance were evaluated with a high-fidelity manometer catheter. Atrioventricular synchronous RV pacing, compared with atrial pacing alone, was associated with a 65% increase in cardiac norepinephrine spillover, an increase in LV end-diastolic pressure, and a reduction in myocardial efficiency. These responses may play a role in the development of heart failure and poor outcomes that are associated with chronic RV pacing.     

Successful percutaneous retrieval of unusually knotted temporary pacemaker lead

Implantation of temporary pacemaker lead is commonly performed procedure and is usually safe, but can sometimes develop rare and serious complication like intracardiac lead knotting which may require challenging retrieval techniques. We report a case of successful percutaneous retrieval of unusually knotted right internal jugular venous temporary pacing lead via left femoral transvenous approach using snare over a long sheath after cutting the electrode proximally and thus avoiding any surgical intervention.     

Pericardial complications of endocardial and epicardial pacing.

A patient with complete atrioventricular block was fitted with a temporary endocardial pacing wire via a right subclavian percutaneous approach. The result was initially satisfactory, but within a few days radiography for left-sided chest pain showed pneumopericardium. A permanent epicardial pacing system was therefore substituted and she remained well for three months. She was then admitted for syncope: the pacemaker was failing to capture, and radiography showed pericardial and pleural effusion. A new permanent endocardial pacing system using a wedged electrode was inserted and she made an uncomplicated recovery. Pneumopericardium complicating endocardial pacing has apparently not been reported before. Presumably the electrode had penetrated both the right ventricle and the pericardium into the adjacent lung.     

Clinical advances in diaphragm pacing

Diaphragmatic pacing is a valuable tool that can significantly benefit certain patients with respiratory insufficiency provided they have an intact phrenic nerve and a functional diaphragm. Careful patient selection is critical to successful long-term results. The main populations that derive benefit from pacing include those with congenital or acquired central hypoventilation syndrome and more commonly those with a high cervical spinal cord injury, where the phrenic nerves remain intact. The pacing electrode of most phrenic nerve pacemakers is implanted directly on the phrenic nerve. A newer device relies on intramuscular implantation of the electrode on the diaphragm at the phrenic nerve motor point. Most patients can be successfully weaned from mechanical ventilation for a substantial time each day, if not completely. This has significant impact on quality of life and implications for healthcare costs. The potential exists for application of this technology to patients with other types of respiratory failure as investigative experience emerges. These include the chronic progressive disease, amyotrophic lateral sclerosis, or temporary scenarios in difficult-to-wean intensive care unit patients. This enabling technology should hold a place in the thoracic surgeon's armamentarium.     

Torsades de pointes,a common arrhythmia,induced by medication.

Between May 1980 and April 1981 four patients were referred to one hospital with syncope or recurrent ventricular fibrillation while taking antiarrhythmic or phenothiazine drugs. In all the patients ventricular tachyarrhythmias with the characteristics of torsades de pointes were documented in association with prolonged QT intervals. With removal of the offending agent (in all the patients) supplemented by temporary overdrive pacing (in two patients) the tachyarrhythmias subsided. This study suggests that drug-induced torsades de pointes is an important clinical entity that occurs more frequently than has been suspected.     

Novel Technique of Dual Chamber Pacing Through Minithoracotomy and Transatrial Endocardial Active Fixation Lead Insertion for Epicardial Pacing Lead Malfunction

Epicardial pacing lead fixation is employed in patients with cavopulmonary anastamosis (Glenn shunts) when they need permanent pacing. Epicardial pacing in these patients may malfunction due to high pacing thresholds or diaphragmatic pacing. A novel technique of transatrial insertion of two endocardial screw-in pacing leads through right anterolateral minithoracotomy could achieve synchronous atrioventricular pacing in a patient with Ebsteins anomaly with symptomatic sinoatrial and atrioventricular nodal disease.     

The effects of right ventricular apical pacing on left ventricular function. Stimulation of the right ventricular apex: should it still be the gold standard?

Current pacing practice is undergoing continuous and substantial changes. Initially pacing had an exclusively palliative role, since it was reserved for patients developing complete heart block or severe symptomatic bradycardia. With the appearance of novel pacing indications such as pacing for heart failure and atrial fibrillation, the effect of pacing site on cardiac function has become a critically important issue and a subject for consideration. It seems that the classical pacing site in the right ventricular apex is no longer the gold standard because of possible disadvantageous effects on cardiac function. The aim of this review article is to discuss the effect of right ventricular apical pacing on cardiac function including cellular and hemodynamic changes. We also aim to discuss the role of alternative pacing sites in the light of cardiac function.     

Selective left bundle branch pacing for pediatric complete heart block

Traditionally Right Ventricle has been the preferred site of pacing for the management of symptomatic brady-arrhythmias. The deleterious effect of chronic RV pacing has been shown by several studies. This has generated interest into a novel pacing strategy called physiological pacing wherein the His bundle or the left bundle is paced directly with 4.1 F pacing lead. Herewith we are reporting a case of congenital complete heart block in a 13-year-old child for whom selective left bundle branch pacing was done. This physiological pacing will ensure a synchronized contraction of the ventricles thereby avoiding the deleterious effect of RV pacing.     

A Novel pacing option in patients with endomyocardial fibrosis: A case series

Endomyocardial fibrosis (EMF) is characterized by fibrous tissue deposition on the endocardial surface leading to impaired filling of one or both ventricles, resulting in either right or left heart failure or both. Although Sinus node dysfunction and tachyarrhythmia - atrial fibrillation, ventricular tachycardia, have been commonly reported, complete heart block (CHB) necessitating a pacemaker is rare in EMF. Transvenous pacing is technically limited by fibrotic obliteration of the affected ventricle that results in poor lead parameters, and alternative pacing strategy like epicardial pacing may be required in many. We report three cases of EMF, who were treated with an alternative pacing strategy.     

Can Right Ventricular Pacing be Useful in the Assessment of Cavo-tricuspid Isthumus Block?

Background

Cavo-tricuspid isthmus (CTI) block is currently assessed by coronary sinus (CS) pacing or low lateral and septal atrial pacing. Occasionally, CS catheterization through the femoral route can be difficult to perform or right atrial pacing can be problematic because of catheter instability or saturation of the atrial electrograms recorded near the catheter.

Objectives

Our aim was to evaluate the feasibility of assessing cavo-tricuspid isthmus block by means of right ventricular (RV) pacing in patients with ventriculo-atrial conduction, comparing it with CS pacing.

Methods

Circumannular activation was analyzed during CS and RV pacing in consecutive patients in sinus rhythm undergoing CTI ablation for typical atrial flutter. Patients without ventriculo-atrial conduction were excluded from the study. The linear lesion was created during RV pacing and split atrial signals on the ablation line were analyzed. CTI block was confirmed by analyzing local electrograms on the line of block and circumannular activation during CS and RV pacing.

Results

Out of 31 patients, 20 displayed ventriculo-atrial conduction (64%) and were included in the study. Before ablation, during RV stimulation, the collision front of circumannular activation shifted counterclockwise in contrast with the pattern observed during CS pacing. After ablation, circumannular activation was similar during CS and RV pacing, showing fully descending lateral right atrium activation, even if double potentials registered on the ablation line were less widely split during RV pacing than CS pacing (111±26 ms vs 128±30 , p=0.0001).

Conclusions

In patients with ventriculo-atrial conduction, tricuspid annulus activation during CS and RV pacing is similar, before and after CTI ablation. The occurrence of split atrial electrograms separated by an isoelectric interval registered on the line of block can be detected during CS or RV pacing. In patients with difficult CS catheterization via the femoral vein, before trying the subclavian or internal jugular route, if retrograde ventriculo-atrial conduction is present, RV pacing can be an easy trick to assess isthmus block.     

Reverse RAMP (REVRAMP) pacing: A novel anti tachycardia pacing technique

Anti-tachycardia pacing (ATP) is frequently used to terminate ventricular tachycardia (VT), however it is not always successful and may accelerate VT requiring defibrillation. REVRAMP is a novel concept of ATP that involves delivering pacing at a faster rate than VT, but instead of abruptly terminating pacing after eight beats, pacing is gradually slowed until VT continues or normal rhythm is restored. In a pilot study we show that REVRAMP can restore normal rhythm, and that if REVRAMP is unsuccessful, VT is not accelerated.     

ICC pacing mechanisms in intact mouse intestine differ from those in cultured or dissected intestine

Pacing of mouse intestine is driven by spontaneous activity of a network of interstitial cells of Cajal in the myenteric plexus (ICC-MP). So far, highly dissected circular muscle (CM) strips from control and mutant mice lacking ICC-MP and isolated, cultured ICC from newborn control mice were used to analyze its properties. Using intact circular and longitudinal segments of intestine, we recently reported that there were both significant similarities and differences between pacing studied in segments and from isolated, dissected tissues. Here, we report additional similarities and differences in our model from those in highly reduced systems. Similar to cultured or dissected intestine, blockade of sarcoplasmic-endoplasmic reticulum Ca(2+) pumps with thapsigargin or cyclopiazonic acid reduced pacing frequency, but thapsigargin was less effective than in isolated, cultured ICC. Moreover, inhibition of inositol 1,4,5-trisphosphate (IP(3)) receptors with xestospongin C, a putative inhibitor of IP(3) receptors, failed to affect pacing but successfully blocked increased pacing frequency by phorbol ester. 2-Aminoethoxy-diphenylborate, a putative blocker of IP(3)-mediated calcium release, caused a significant decrease in the amplitude and frequency of contractions. The mitochondrial uncoupler carbonyl cyanide p-trifluormethoxyphenylhydrazone blocked pacing and KCl-induced contractions at a concentration of 1 microM. The cyclic nucleotide agonists sodium nitroprusside (SNP), forskolin, and 8-bromo-cGMP inhibited pacing in CM. In longitudinal muscle (LM), SNP and forskolin had little effect on pacing. Furthermore, dibutyryl-cAMP did not affect pacing in CM or LM. These results suggest that pacing in intact intestine is under partly similar regulatory control as in more reduced systems. However, pacing in intact intestine is not affected by xestospongin C, which abolishes pacing in isolated, cultured ICC and exhibits attenuated responses to thapsigargin. Also, major differences between LM and CM suggest a separate pacemaker may drive LM.