具有自动阈值管理和房室搜索功能起搏器Enpulse的临床应用

目的动态观察具有自动阈值管理和房室搜索功能起搏器Enpulse的临床应用。方法76例患者植入了Enpulse系列起搏器,于植入时,植入后1,6个月采用手工测试心房、心室起搏阈值和阻抗并与心房、心室自动阈值管理(ACM、VCM)测定的值进行比较,并利用ACM、VCM进行术后阈值和阻抗的动态观察。计算术后心室起搏百分比,并与传统起搏器相比较。结果72例完成随访。手工测试的心房、心室阈值与ACM、VCM测定的无显著性差异。心房、心室起搏阈值均小于1 V,心房起搏阈值于植入1个月后有下降趋势,而阻抗未见有明显变化;心室起搏阈值无明显变化,但阻抗于植入2～6个月时有下降趋势。Enpulse起搏器的心室起搏比例为4.895%±9.0589%,明显小于传统起搏器(79.479%±16.159 3%,n=60)。结论Enpulse的自动阈值管理能自动测定阈值,并以较小的能量输出安全起搏,AV搜寻功能明显减少心室起搏比例。     

自动化起搏器在病窦综合征中的应用分析

目的通过对病窦综合征患者植入自动化起搏器的随访,分析其心房自动阈值管理、心室自动阈值管理、自动房室间期搜索等功能的安全性和有效性。方法选取病窦综合征26例,其中植入Enpluse E2D01起搏器13例、Adapta ADDR01起搏器6例、Kappa 701起搏器7例;植入时Adapta ADDR01起搏器关闭最小心室起搏功能;分别于起搏器植入后1,3,6个月时复查起搏器参数。结果随访的Enpluse、Adapta起搏器病例均完成了心房起搏阈值自动管理;于1,3,6个月随访时,手动与自动测量的心房阈值无差异。所有随访的病例均完成心室起搏阈值自动管理;于1,3,6个月随访时,手动与自动测量心室阈值无差异。术后随访患者大部分心室事件为感知事件。结论 Enpluse、Adapta、Kappa起搏器的自动化功能安全、有效。     

Zephyr5826起搏器心房自动阈值管理的临床观察

目的动态观察Zephyr5826起搏器心房自动阈值管理(ACM)功能的开启情况、准确性及安全性。方法选取置入Zephyr5826起搏器患者68例,于置入术后第1,7天及1,2,3,6个月时随访程控,观察ACM功能的开启情况,手工测试心房起搏阈值并与ACM功能测定的值进行比较。结果 68例均完成随访。随访期内35例(51.50%)成功开启ACM功能,其中术后第1,7天及1,2,3个月时开启例数分别为14例(20.6%)、21例(30.9%)、26例(38.2%)、28例(41.2%)和32例(47.1%)。手工测试与ACM测试的心房阈值无差异。33例因起搏器自动测定心房刺激除极波(ER)过小不推荐开启ACM功能。随访期间心电图及动态心电图(Holter)均未见心房失夺获及感知不良。与普通电压和高电压起搏相比,自动阈值管理功能在心房输出方面分别节省50%,88%的能量消耗。结论 Zephyr5826起搏器ACM功能可以安全有效的应用低能量起搏心脏。部分患者术后因起搏器测定心房ER过小未能开启ACM功能,但在随访过程中ACM的开启比例逐渐升高。     

EnPulse起搏器自动化功能的临床研究

目的:通过对EnPulse起搏器安置患者的随访,了解心房及心室自动阈值管理、自动AV间期搜索等功能的安全性和有效性.方法:选取置入Enpluse E2D01起搏器患者15例,分别于起搏器置入后1个月及6个月时复查起搏器参数,包括起搏器最近1次自动测量的心房及心室起搏阈值,手动测量心房及心室起搏阈值,记录患者心室感知占心室总事件的比例,并记录由Search AV+所设定AV间期基础上的心室感知事件所占心室总事件的比例.结果:1个月及6个月随访时,手动测量心房及心室阈值与自动测量心房及心室阈值差异无统计学意义.术后病态窦房结综合征患者大部分心室事件为感知事件,其中绝大多数由search AV+功能参与.结论:EnPulse起搏器的自动AV搜索功能、心房及心室自动阈值管理是安全有效的.     

起搏器心房自动阈值管理功能的临床研究

目的:通过对植入起搏器患者的随访,了解心房自动阈值管理功能的可靠性和安全性。方法:选择植入Medtronic Enpulse双腔起搏器的患者43例,于植入起搏器后的1、3、6个月分别程控随访,用人工测定法和自动测定法测定起搏器的心房输出阈值、感知和导线阻抗。结果:植入起搏器1、3、6个月后,随访时人工测定和自动测定的心房输出阈值分别为(0.60±0.26)V与(0.60±0.23)V、(0.55±0.19)V与(0.56±0.18)V、(0.58±0.20)V与(0.59±0.21)V,差异无统计学意义;且心房感知度和导线阻抗的人工测定与自动测定间无差异。在心房自动起搏阈值测定过程中未诱发任何心律失常。结论:起搏器的心房自动阈值管理功能的临床应用是可靠和安全的。     

双房单室三腔起搏器治疗病窦综合征并快速房性心律失常

观察双心房、单心室三腔起搏器治疗病窦综合征合并阵发性房性快速心律失常患者的疗效。三根电极导线分别置入冠状静脉窦内、右心耳和右室心尖部行三腔起搏。冠状窦电极导线与右心房电极导线通过一个Y型转接器构成心房部分。结果 :10例患者 ,9例经左锁骨下静脉径路置入导线 ,1例因存在残存左上腔静脉 ,从右锁骨下静脉置入。 10例中 9例冠状窦电极导线置于冠状静脉窦中部、1例置于冠状静脉窦远端。冠状窦起搏阈值为 1.0 6±0 .2 0V、起搏阻抗 6 11± 115 .8Ω、P波振幅为 4.0 7± 0 .88mV ;右室电极起搏阈值为 0 .5 3± 0 .12V、起搏阻抗 6 70 .3±191.7Ω、R波振幅为 9.6 6± 1.87mV。随访 5～ 2 4个月有 9例起搏器呈DDD工作方式 ,1例呈AAT工作方式。起搏和感知功能良好。 10例中 8例快速性房性心律失常完全控制 ,2例发作次数减少 ,持续时间明显缩短。无一例出现并发症。结论 :三腔起搏器技术安全、可靠。适合于缓慢型心律失常合并阵发性房性快速性心律失常     

Zephyr DR型起搏器自动夺获功能的临床随访

目的:通过对植入Zephyr DR型起搏器患者的随访,了解心房及心室自动阈值管理的安全性和有效性。方法:对植入Zephyr DR型起搏器7例患者,分别于起搏器植入后1、3、6个月复查起搏参数,包括自动测量心房、心室起搏阈值,手动测量心房、心室起搏阈值。结果:1、3、6个月随访时心房、心室自动测试和手动测试测得的阈值差异无统计学意义(P>0.05)。结论:Zephyr DR型起搏器自动阈值夺获功能耗能低而且安全有效。     

心房起搏自动阈值管理功能的临床应用

起搏器起搏阈值是指起搏器起搏心脏需要的最小电能,即起搏器的最低输出.其大小受生理、病理、药物等诸多因素影响常处于波动状态,会增加起搏器能量消耗,减少起搏器使用寿命,可能造成起搏器阈值升高时的失夺获[1].1972年,Funke首先提出通过起搏器自动检测心脏起搏阈值,并以高于起搏阈值较少的能量起搏心脏,可增加起搏器应用安全性,延长起搏器电池寿命.大量研究证实,心室起搏阈值的自动测定和自动调整功能成为评价心室起搏功能的金标准[2-4].与心室除极波相比,心房除极波很小,很难通过测量心房电脉冲刺激后心房除极波判断刺激脉冲是否真正夺获心房,因此,心房自动阈值管理一直是临床一大难题.本文就起搏器心房阈值管理功能的相关研究及临床应用作一综述.     

胺碘酮对病态窦房结综合征患者起搏参数的影响

目的 :研究口服胺碘酮对病态窦房结综合征 (病窦综合征 )患者起搏参数的影响 ,为安置人工心脏起搏器后 ,因快速性房性心律失常口服胺碘酮是否安全提供证据。方法 :对 4 5例病窦综合征患者 ,置入心脏起搏器。其中 2 5例伴快速性心律失常的患者口服胺碘酮 ,另外 2 0例为对照 ,监测起搏参数。结果 :术后两组患者均有心室起搏阈值升高 ,感知阈值和电极阻抗下降。两组相比较 ,胺碘酮治疗组 ,术后第 4天至第 3个月起搏阈值升高更显著、感知阈值和电极阻抗下降更明显。结论 :胺碘酮对病窦综合征患者起搏参数有一定程度的影响。     

具有自动夺获功能心室起搏器的临床观察

我科1998年1月至10月共植入具有自动夺获功能心室起搏器6例,男4例、女2例,年龄64.3±10.5岁。植入起搏器的适应证为病窦综合征2例、度房室阻滞2例、度型房室阻滞2例。其中合并阵发性心房扑动1例、合并阵发性心房颤动2例。植入起搏器均为Pacesetter公司的RegencySC (VVI型),电极亦为该公司提供的带有激素释放功能的低极化1470T双极电极。起搏器植入手术与普通VVI起搏器相同。术中除常规测定起搏阈值、阻抗、R波振幅外,尚需加测刺激除极波(ER)的振幅。术后当天,用APSu3250型程控仪将起搏器自动夺获功能打开。术后1周及1,3,6,9个月进行…     

Automatic measurement of atrial pacing thresholds in dual-chamber pacemakers: Clinical experience with atrial capture management

BACKGROUND: The Medtronic EnPulse pacemaker incorporates the new atrial capture management (ACM) algorithm to automatically measure atrial capture thresholds and subsequently manage atrial pacing outputs. OBJECTIVES: The purpose of this study was to evaluate the clinical performance of ACM. METHODS: Two hundred patients with an indication for a dual-chamber pacemaker underwent implantation. ACM thresholds and manually measured atrial pacing thresholds were assessed at follow-up visits. Clinical equivalence was defined as the ACM-measured threshold being within -0.25 V to +0.5 V of the manually measured threshold. The clinician analyzed all ACM measurements performed in-office for evidence of proarrhythmia. RESULTS: All 200 implanted patients had a 1-month visit, and validated manual and in-office ACM threshold data were available for 123 patients. The ACM threshold was 0.595 +/- 0.252 V, and the manual threshold was 0.584 +/- 0.233 V. The mean difference was 0.010 V with a 95% confidence interval of (-0.001, 0.021). The mean difference over all visits was 0.011 V. For all patients, the individual threshold differences were within the range of clinical equivalence at all visits. No atrial arrhythmias were observed during 892 ACM tests in 193 patients. CONCLUSION: This study demonstrated that the ACM algorithm is safe, accurate, and reliable over time. ACM was demonstrated to be clinically equivalent to the manual atrial threshold test in all patients at 1 month and over the entire follow-up period of up to 6 months. ACM ensures atrial capture, may save time during follow-up, and can be used to manage atrial pacing outputs.     

Atrial pacing and sensing characteristics in heart failure patients undergoing cardiac resynchronization therapy.

Patients with heart failure and sinus rhythm undergoing cardiac resynchronization therapy (CRT) require the proper detection of atrial signals and reliable atrial pacing for AV-synchronous ventricular pacing. The study aim was to compare atrial pacing and sensing characteristics in patients with transvenous CRT and patients with standard pacing indications. METHODS: The study group consisted of 31 heart failure patients with depressed left ventricular function and bundle branch block, and the control group of 124 patients with dual-chamber pacemakers because of standard pacing indications. The bipolar steroid-eluting atrial screw-in lead Tendril DX 1388 T (St. Jude Medical) was implanted and connected to pulse generators that provide similar diagnostic features. The unipolar pacing threshold at 0.4 ms duration, bipolar sensing threshold, and unipolar pacing impedance were determined at implantation and after 1, 3, and 6 months. RESULTS: At implantation, the atrial pacing threshold was significantly higher in the CRT group than in the control group, 1.07+/-0.99 V versus 0.74+/-0.36 V (P<0.01). Similar pacing thresholds were recorded after 1 month. The pacing threshold in the CRT group was significantly higher at 1.46+/-0.92 V after 3 and 1.50+/-0.94 V after 6 months (control group: 0.96+/-0.25 V at month 3; 0.98+/-0.32 V at month 6; P<0.05). Sensing threshold was similar at implantation with 2.36+/-1.87 mV in the CRT and 2.54+/-0.78 mV in the control group. The sensing threshold in the CRT group decreased to 1.64+/-0.8 6mV after 3 and to 1.71+/-0.71 mV after 6 months and was significantly lower compared with the control group (2.16+/-0.57 mV at month 3; 2.27+/-0.9 8mV at month 6; P<0.05). At implant, the atrial pacing impedance was not different between the two groups with 443+/-156 ohms in the CRT and 416+/-116 ohms in the control group. During follow-up, the impedance became significantly lower in the CRT group compared with the control group (404+/-84 ohms versus 452+/-101 ohms at month 3; P<0.05). CONCLUSIONS: Compared with patients with standard pacing indications, CRT recipients have less good electrical characteristics in the atrium. Atrial pacing and sensing function should be closely monitored in CRT patients.     

Benefits of dual chamber pacing in sick sinus syndrome

The effects of DDD (fully automatic) and VVI (ventricular demand) pacing modes on exercise tolerance, symptom diary cards, and Holter monitoring were investigated in a randomised double blind crossover study of 16 patients who had had DDD pacemakers implanted because of frequent syncope. Eight patients presented with sick sinus syndrome and, with one exception, retrograde atrioventricular conduction and eight age and sex matched patients presented with 2:1 or complete atrioventricular block. Maximal symptom limited exercise in those with atrioventricular block was significantly higher after one month of DDD pacing than after VVI pacing. In those with sick sinus syndrome, however, maximal effort tolerance was not significantly different for the two pacing modes. In all but one patient with sick sinus syndrome sinus rhythm developed during exercise in VVI pacing. For both VVI and DDD modes maximal atrial rates were significantly lower in those with sick sinus syndrome. Palpitation and general wellbeing were significantly improved during DDD pacing in the eight patients with sick sinus syndrome. Shortness of breath was improved by DDD pacing in the eight patients with atrioventricular block but not in those with sick sinus syndrome. Holter monitoring showed that sick sinus syndrome patients remained in paced rhythm, either DDD or VVI, for most of the 24 hour period. DDD pacing was better than VVI pacing in sick sinus syndrome with retrograde atrioventricular conduction. Despite their ability to show sinus rhythm and inhibit their pacemakers on exercise patients with sick sinus syndrome are just as likely to have symptomatic benefit from DDD pacing as patients with atrioventricular block.     

Benefits of dual chamber pacing in sick sinus syndrome.

The effects of DDD (fully automatic) and VVI (ventricular demand) pacing modes on exercise tolerance, symptom diary cards, and Holter monitoring were investigated in a randomised double blind crossover study of 16 patients who had had DDD pacemakers implanted because of frequent syncope. Eight patients presented with sick sinus syndrome and, with one exception, retrograde atrioventricular conduction and eight age and sex matched patients presented with 2:1 or complete atrioventricular block. Maximal symptom limited exercise in those with atrioventricular block was significantly higher after one month of DDD pacing than after VVI pacing. In those with sick sinus syndrome, however, maximal effort tolerance was not significantly different for the two pacing modes. In all but one patient with sick sinus syndrome sinus rhythm developed during exercise in VVI pacing. For both VVI and DDD modes maximal atrial rates were significantly lower in those with sick sinus syndrome. Palpitation and general wellbeing were significantly improved during DDD pacing in the eight patients with sick sinus syndrome. Shortness of breath was improved by DDD pacing in the eight patients with atrioventricular block but not in those with sick sinus syndrome. Holter monitoring showed that sick sinus syndrome patients remained in paced rhythm, either DDD or VVI, for most of the 24 hour period. DDD pacing was better than VVI pacing in sick sinus syndrome with retrograde atrioventricular conduction. Despite their ability to show sinus rhythm and inhibit their pacemakers on exercise patients with sick sinus syndrome are just as likely to have symptomatic benefit from DDD pacing as patients with atrioventricular block.     

Blind atrial pacing for patients with sinus node disease who develop atrial fibrillation during permanent pacemaker implantation

During a 6-year period, six of 110 patients implanted with AAI pacemakers for sick sinus syndrome developed atrial fibrillation at the time of pacemaker implantation (5.5%). In all cases a passive fixation lead was sited in the right atrial appendage, its stability being ensured by rotation of the lead and phrenic nerve stimulation excluded by pacing at 10 V. One patient remained in chronic atrial fibrillation. In the other five, who subsequently reverted to sinus rhythm, atrial P-wave sensing and lead threshold values were satisfactory, allowing programming of the pacemaker output down to 2.5 V to conserve the battery. One out of these five patients continued to have intermittent atrial fibrillation. We conclude that in sick sinus syndrome, atrial fibrillation complicates AAI pacemaker implantation procedure in 5.5% of cases. As an alternative to an unplanned general anaesthetic to cardiovert the patient, it is reasonable to implant an atrial lead in the right atrial appendage in the expectation of a spontaneous reversion to sinus rhythm with a good lead threshold and P-wave sensing. In contrast to inappropriate pacing of the right ventricle in VVI mode, this strategy avoids pacemaker syndrome and reduces the risk of subsequent attacks of atrial fibrillation.