阵发性心房颤动的起搏预防与治疗

心房颤动是临床十分常见的心律失常。其发生随着年龄逐渐增加,60岁以下的房颤发生率低于1%,而70岁以上的老年人心房颤动的发生率高达10%以上。心房颤动的危害极大已是众所周知,主要包括:(1)使血栓栓塞事件增加4~10倍;(2)可诱发或加重充血性心力衰竭,房颤减少心排出量10%~45%;(3)使窦房结和房室结功能急剧下降;(4)使患者的生活质量下降或恶化,诱发心衰时甚至成为功能性残疾人;(5)房颤可使死亡率增加达2倍。这些都说明心房颤动并非是一种良性心律失常,必须给予有效的预防和治疗。1房颤起搏治疗和预防的机制房颤发生的主要因素包括触发因素和基…     

特殊起搏程序预防阵发性心房颤动的临床应用

心房颤动(房颤)是临床上最常见的持续性心律失常，发生率随年龄的增长而增高，是老年人缺血性脑卒中的主要原因之一，严重影响患者的生活质量。对阵发性房颤进行早期干预，防止过早地进展为慢性房颤成为临床治疗的主要目标之一。电生理机制的研究表明，房性早搏(房早)等触发因素在房颤的发生中起着重要的作用。Vitatron公司根据常见     

双心房同步起搏治疗阵发性心房颤动的长期疗效观察

双心房同步起搏治疗病态窦房结综合征（病窦综合征）伴有房间阻滞的药物难治性阵发性房性心律失常如阵发性心房颤动（房颤）和心房扑动，国内从1998年开始陆续有部分病例报道，取得了一定的临床效果，但随访的时间都较短。本文报道了自1998年10月到2000年11月间在我院13例植入了双心房同步起搏器患者随访至今的结果，对双心房起搏预防阵发性房颤的长期疗效及冠状静脉窦起搏左心房的安全性和有效性进行探讨和评估。[第一段]     

冠状静脉窦起搏治疗阵发性心房颤动

心房颤动 (房颤 )的治疗一直是临床难点 ,起搏治疗是临床的选择之一。 1997年 ,Papageorgiou等[1] 的电生理研究表明冠状静脉窦起搏能有效防止房颤发生 ,但冠状静脉窦起搏治疗阵发房颤的长期临床应用尚未见报道。资料和方法患者 6例 ,男性 ,年龄 6 4～ 79(平均 6 9 2 )岁。 6例均为病态窦房结综合征 (病窦 )患者 ,其中 3例合并高血压性心脏病。超声心动图测定左心房直径为 2 7 3～ 37 5 (平均33 7)mm ,其中 3例左心房增大。 6例患者均反复发生阵发性房颤 ,其中 2例合并心房扑动、1例合并二度房室阻滞 ,5例窦性心律时体表心电图P波时限≥ 0 …     

不同部位起搏对阵发性心房颤动患者心房激动时间的影响

目的　比较右心耳 (RAA)、冠状窦远端 (DCS)、右心房双部位 (右心耳加冠状窦口 ,DSA)和双房 (右心耳加冠状窦远端 ,Bi A)起搏对阵发性心房颤动 (PAf)患者心房激动时间的影响。方法 2 2例接受心脏电生理评价试验的PAf患者在窦性心律下行心房不同部位起搏 ,同步记录 12导心电图 ,测量最大 P波时限。结果　与窦性 P波时限相比 ,RAA起搏明显延长 P波时限 (P<0 .0 1) ,DCS、DSA及 Bi A起搏则明显缩短 P波时限 (P<0 .0 1,P<0 .0 1,P<0 .0 1)。结论　 DCS、DSA及 Bi A起搏明显缩短心房激动时间 ,减少心房电活动的离散度 ,有利于 PAf的防治。     

900E起搏治疗阵发性心房颤动

目的观察Vitatron900E治疗阵发性心房颤动(paroxysmalatrialfibrillation,PAf)的疗效。方法将15例PAf患者植入Viatron900E起搏器,与植入普通全自动双腔(DDD型)起搏器PAf的患者进行疗效比较。结果900E组总有效率为80%,而全自动双腔起搏器组有效率为25%(P<0.05)。结论900E治疗PAf优于DDD起搏器。     

心房起搏治疗心房颤动

近年来起搏器新功能如自动频率夺获心房起搏方式 ,频率平稳功能 ,频率适应性功能的出现 ,以及双心房同步或心房多部位起搏技术的临床应用 ,明显提高了心房起搏的抗心律失常作用 ,使心房起搏已成为治疗心房颤动 (房颤 )的重要、有效的方法。　　一、治疗和预防心房颤动的心房起搏方式　　按照心房起搏部位 ,治疗和预防房颤的心房起搏可分为两种 1单部位心房起搏 [1] :单部位心房起搏的位置可在右心耳、高位右房、右侧房间隔、界嵴、冠状静脉窦开口附近等部位。右心耳是目前最常采用的部位 ,仅需被动固定方式的心房导线电极则可。而高位右房或…     

DDD起搏对病窦综合征患者阵发性心房颤动的远期影响

为观察DDD起搏对病窦综合征(SS)患者阵发性心房颤动(AF)的远期影响，对既例合并阵发性AF的病窦综合征患者，择期置人DDD永久起搏器，术后进行临床、心电图、24h动态心电图的定期随访，观察比较DDD起搏器置人术前1年、术后1，2，5年的阵发性AF发作频率以及发作持续时间。结果：所有患者起搏器置人后随访1。2年阵发性AF发作的频率及发作的时间较起搏器置人前显著减少(T0—1146，T0—2137，P均＜0．05)；术后随访5年时阵发性AF发作的频率及发作的时间较术后1～2年显著增加(T1—5143，T2—121，P均＜0．05)。所有患者术后无心力衰竭、血栓栓塞发生。结论：DDD起搏对SSS并发的阵发性AF的发生有抑制及预防作用，这种影响在起搏器治疗近中期最为显著，远期疗效不肯定尚需进一步临床观察。     

动态心房超速起搏预防阵发性房颤

目的观察动态心房超速起搏预防阵发性房颤的临床疗效和安全性。方法选择病态窦房结综合症伴阵发性房颤,并需植入永久起搏器的患者8例,分别植入具有动态心房起搏功能的起搏器,PacessetterTrilogy23643例,VitatronSelectionTM900E5例;随访6个月,前3个月不打开动态心房起搏功能,后3个月打开动态心房起搏功能,根据起搏器记录到的模式转换次数和持续时间来判断其预防房颤发作的疗效。结果打开动态心房起搏功能前后,患者房颤发作的次数分别为2437±956次/月和472±135次/月(P<0.05);模式转换持续时间分别为173±105小时/月和48±25小时/月(P<0.05);房颤负荷分别为33±8%和10±7%(P<0.05)。结论动态心房超速起搏,是阵发性房颤预防治疗的有效和安全的方法之一。     

起搏预防阵发性快速性房性心律失常

阵发性快速性房性心律失常主要包括阵发性房性心动过速 (房速 )、心房扑动 (房扑 )及心房颤动 (房颤 ) ,临床较常见 ,呈反复、交替、频繁发作。这一方面可抑制窦房结自律性 ,导致窦房结功能障碍 ;另一方面可使心房发生电重塑 ( electrical remodeling)及收缩功能障碍。这些结果又反过来促进快速性房性心律失常发作 ,形成恶性循环。多数患者最终将演变成永久性房颤 ,使心功能明显减退 ,可诱发或加重心力衰竭 ,严重影响患者的生活质量。另外 ,房颤尤其是阵发性房颤是血栓栓塞的主要原因。抗心律失常药物对此类心律失常疗效较差 ,长期服用抗心…     

特殊心房起搏程序预防和治疗心房颤动研究进展

心房颤动是临床上最常见的心律失常之一,严重影响了患者的生活质量,增加病死率。根据心房颤动发生的电生理机制,许多起搏器公司设计了可以减少或预防心房颤动发生的起搏程序。现就这些特殊程序的具体工作原理做一综述。     

Effect of Atrial Tachyarrhythmia Duration on Percentage of Time with Atrial Pacing in Pacemaker Patients with Paroxysmal Atrial Fibrillation

Atrial pacing can prevent the recurrence of paroxysmal atrial tachyarrhythmia (AT) in pacemaker patients. The aim of the study was to determine in pacemaker patients the effect of AT duration on the percentage of time with atrial pacing by programming the same setting twice. METHODS: In 14 pacemaker patients with paroxysmal AT the dual-chamber pacemaker was programmed to identical parameters for two consecutive follow-up periods. The pacemakers were interrogated after three months to determine the percentage of time with atrial pacing relative to the total time of follow-up periods and the AT duration (atrial rates >150 bpm). The two three-month follow-up periods were compared to each other. The differences between the two follow-up periods were determined for the percentage of time with atrial pacing as well as for the AT duration. To assess the relationship between atrial pacing and AT duration, the differences between the two follow-up periods for atrial pacing and AT duration were correlated to each other. In addition, the percentage of atrial pacing was corrected for AT duration. RESULTS: Median percentage of atrial pacing relative to the complete follow-up period was 73% after the first and 76% after the second period and median AT duration 21% and 18%, respectively (not significantly different). The differences between the first and second study period were 1% for atrial pacing and -2% for AT duration. The percentage of atrial pacing and AT duration were inversely related together with a significant correlation coefficient of r = 0.95 ( p = 0.0001). After atrial pacing was corrected for AT duration, the percentage of atrial pacing relative to the time in sinus rhythm was significantly higher with a median of 93% for the first and second period ( p = 0.005). The correlation coefficient between the percentage of atrial pacing relative to the time in sinus rhythm and AT duration was r = 0.08 (not significant). CONCLUSIONS: The percentage of time with atrial pacing can be underestimated in patients with paroxysmal atrial fibrillation and should be carefully interpreted in relation to AT duration.     

Dual Site Right Atrial Pacing can Improve the Impact of Standard Dual Chamber Pacing on Atrial and Ventricular Mechanical Function in Patients with Symptomatic Atrial Fibrillation: Further Observations from the Dual Site Atrial Pacing for Prevention of Atrial Fibrillation Trial

Background: The effects of atrial pacing mode on atrial and ventricular function in patients with atrial fibrillation (AF) and bradycardia have not been evaluated. We evaluated atrial and ventricular function during randomization to support pacing (SP), high right atrial pacing (HRA), and dual site right atrial pacing (DAP).Methods: Seventy-nine patients (66 ± 12 yr, 46 male) with standard pacing indications and symptomatic AF were randomized to each of three pacing modes (DAP, HRA, SP) for 6 months in a crossover design. Echocardiographic studies were performed at enrollment and the end of each mode. Paired comparisons of atrial and ventricular function parameters were performed between each pacing mode and baseline.Results: HRA pacing in DDDR mode resulted in increased left ventricular (LV) end systolic volume (78 ± 42 vs. 60 ± 31 ml, p = 0.001) and reduced LV ejection fraction (44 ± 14 vs. 50 ± 11%, p = 0.007) compared to baseline. These parameters did not change during DAP. DAP resulted in increased peak A wave velocity (75 ± 19 vs. 63 ± 23 cm/s, p = 0.003) and atrial filling fraction compared to baseline (0.47 ± 0.15 vs. 0.38 ± 0.13, p = 0.005). Atrial and ventricular function were similar between control and SP.Conclusion: DAP, but not HRA or SP, improved left atrial (LA) function in patients with AF and bradycardia. HRA pacing in DDDR mode resulted in LA dilatation and deterioration of LV function which was not observed with DAP.This study was supported by a grant from the Electrophysiology Research Foundation, Warren, NJ and Medtronic Inc., Minneapolis, MN. Drs. Delfaut and Prakash were supported by grants from the Electrophysiology Research Foundation during the term of this study. Drs. Saksena and Nanda were consultants to Medtronic during this study. Dr. Hettrick and Mr. Ziegler are employees of Medtronic.     

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.     

阵发性心房颤动发生的相关研究进展

尽管对阵发性心房颤动的认识已增加了不少,但是对自然状态下发作的阵发性心房颤动的触发方式的细节研究还是少之又少。通过对其相关心电图特征的研究以更好的了解阵发性心房颤动的发生。     

Pacing to Prevent Atrial Fibrillation

Introduction: Pacing has been proposed as a nonpharmacologic treatment option to prevent atrial tachyarrhythmias (ATs) in drug-refractory patients. This article reviews the current state of pacing to prevent ATs.
Methods and Results: Different pacing modalities have been assessed with regard to their ability to prevent AT: conventional DDDR pacing with elevated lower rate limit, biatrial pacing, dual-site right atrial pacing, atrial septal pacing, and pacing with the use of dedicated pacing algorithms. Small studies suggest a benefit of conventional pacing for AT prevention in patients with bradycardia, but a randomized trial did not reveal any AT reduction by conventional pacing in patients without bradycardia. AT prevention by biatrial or dual-site right atrial pacing has been reported in small studies, but randomized trials did not show a clear benefit of these pacing techniques. Small studies showed a reduced AT recurrence rate in patients with septal pacing at the triangle of Koch or at Bachmann's bundle. Two large randomized trials with preventive pacing algorithms showed a significant AT reduction compared to conventional pacing, but this was not confirmed in four trials.
Conclusion: Pacing seems to be able to suppress ATs in a minority of patients; however, prospective identification of responders to different pacing modalities does not appear to be feasible at the present time. (J Cardiovasc Electrophysiol, Vol. 14, pp. S20-S26, September 2003, Suppl.)     

Atrial Pacing Therapies for Prevention of Atrial Fibrillation in Patients with Implantable Defibrillators

Atrial fibrillation (AF), atrial flutter and atrial tachycardia (AT) occur frequently in patients following implantation of an implantable cardioverter defibrillator (ICD) for the treatment of ventricular tachyarrhythmias. Some new generation ICDs have incorporated atrial antitachycardia pacing therapy (ATP) and atrial pacing algorithms designed specifically for the prevention of AF. In the GEM III AT clinical evaluation, atrial ATP efficacy for termination of AF and AT was assessed. Overall ATP efficacy for AF/AT, based on device classification, was 40% when adjusted using the Generalized Estimating Equations to account for correlated data that arises from utilizing multiple episodes in some patients. However, many episodes of AF/AT were noted to terminate within 10 minutes of onset. Applying a more conservative definition of efficacy, termination within 20 sec of delivery of the last atrial ATP, efficacy for termination of AF/AT was 26%. 50 Hz burst pacing was shown to have minimal efficacy for termination of AF and modest incremental benefit following ramp or burst pacing therapies for AT. These observations provide a more realistic expectation of the value of atrial ATP in the ICD population with AF. Atrial ATP terminates some episodes of AT but previously reported efficacy rates of 40-50% are exaggerated and in part reflect spontaneous terminations of some AF/AT episodes.     

Effects of High-Frequency Atrial Pacing in Atypical Atrial Flutter and Atrial Fibrillation

Atypical atrial flutter has, hitherto, been relatively refractory totermination by rapid atrial pacing. High-frequency pacing (HFP) in theatrium, for termination of atrial flutter or atrial fibrillation (AF), andthe electrophysiologic effects related to it have not been examined. Weexamined the clinical efficacy, safety, and electrophysiologic mechanisms ofHFP using 50-Hz bursts at 10 mA applied at the high right atrium in patientswith atypical atrial flutter (group 1) or AF (group 2), using a prospectiverandomized study protocol. Four burst durations (500, 1000, 2000, and 4000ms) were applied at the high right atrium repetitively in random sequence in22 patients with spontaneous atrial flutter or AF. Local and distant rightand left atrial electrogram recordings were analyzed during and after HFP.HFP resulted in local and distant right and left atrial electrogramacceleration in 8 of 10 patients (80%) in group 1 but caused lessfrequent local atrial electrogram acceleration (6 of 12 patients) and nodistant atrial electrogram effects in group 2 (p < .05 versus group 1).The HFP protocol was effective in arrhythmia termination in 6 of 10patients in group 1 but in no patient in group 2 (p < .05 versus group1). Standard HFP protocol applied at the high right atrium can frequentlyalter atrial activation in both atria and can terminate atypical atrialflutter. Efficacy in AF is limited, probably due to limitedelectrophysiologic actions beyond the local pacing site.     

Prevention of Short Term Reversible Chronic Atrial Fibrillation by Permanent Pacing at the Triangle of Koch

Objectives: The purpose of this study was to investigate if single lead interatrial septum pacing could be effective in maintaining sinus rhythm in patients in whom restoration of sinus rhythm was only possible for a period of 2–24 hours after one or more previous electrical cardioversions, and in whom a sinus bradycardia was documented before arrhythmia restarted. The two hours limit was chosen because it was considered a sufficient time to implant a dual chamber pacemaker. Background: Alternative atrial pacing techniques have been demonstrated to be successful in preventing recurrences of atrial fibrillation (AF) in patients with sinus bradycardia. Excluding the AF occurring after only a few sinus beats, at 24 hours from electrical cardioversion an early restart of chronic AF has been reported in 12[emsp4 ]% to 17[emsp4 ]% of the patients. Methods: After sinus rhythm was restored by internal electrical cardioversion, 17 patients, 7 ablated at the AV junction, underwent a dual chamber rate response (DDDR) pacemaker implantation with a screw-in atrial lead placed in the interatrial septum. Results: After a follow-up period of 17±5 months (range 12 to 27 months) persistence of sinus rhythm was observed in 11 patients (65[emsp4 ]%). Six patients (35[emsp4 ]%) had recurrences of paroxysmal attacks, while five (30[emsp4 ]%) were totally free of AF. Recurrence of chronic AF was observed in six cases (35[emsp4 ]%) after 2 days–12 months from implantation. No dislodgements of the atrial lead and no complications were observed at implantation and during follow-up. Conclusions: Interatrial septum pacing is a safe and feasible technique with a satisfying success rate (65[emsp4 ]%) in long-term maintaining sinus rhythm in previously unsuccessfully cardioverted patients.     

Clinical Value of Noninducibility by High-Dose Isoproterenol Versus Rapid Atrial Pacing After Catheter Ablation of Paroxysmal Atrial Fibrillation

Noninducibility by High‐Dose Isoproterenol. Objective: To determine the relative clinical value of noninducibility of atrial fibrillation (AF) by isoproterenol (ISO) and by rapid atrial pacing (RAP) in patients with paroxysmal AF (PAF). Background: AF can be induced by RAP or ISO in >85% of patients with PAF. Methods: ISO was administered in escalating doses of 5, 10, 15, and 20 μg/min in 112 patients (age = 56 ± 13 years) with PAF before radiofrequency catheter ablation. AF was inducible in 97 of 112 patients (87%) at a mean dose of 15 ± 5 μg/min. RAP induced AF in the remaining 14 of 15 patients. Antral pulmonary vein (PV) isolation (APVI) was followed by ablation of complex fractionated atrial electrograms (CFAEs) as necessary to terminate AF and render AF noninducible in response to ISO. Results: AF terminated during APVI in 72 of 111 patients (65%) and after APVI plus ablation of CFAEs in 11 of 111 patients (10%). In the remaining 28 patients (25%), sinus rhythm was restored by transthoracic cardioversion. RAP was performed in the last 61 consecutive patients who were rendered noninducible by ISO. RAP initiated AF in 20 of 61 patients (33%) and atrial flutter in 6 patients (10%). No additional ablation was performed if AF was induced with RAP; however, atrial flutter was targeted. At 12 ± 5 months, 63/75 patients (84%) who were noninducible by ISO and 2 of 8 (25%) who still were reinducible by ISO were free from recurrent AF after a single ablation procedure without antiarrhythmic drugs (P = 0.001). AF recurred in 20 of 36 patients (56%) who required cardioversion for persistent AF after ablation (P < 0.001). Among the 61 patients who also underwent RAP, 12 of 20 (60%) who were, and 31 of 41 (76%) who were not inducible by RAP were free from recurrent AF (P = 0.21). The accuracy of noninducibility as a predictor of clinical outcome was 83% with ISO and 64% by RAP (P = 0.03). Conclusions: The response to isoproterenol after catheter ablation of PAF more accurately predicts clinical outcome than the response to RAP. (J Cardiovasc Electrophysiol, Vol. 21, pp. 13–20, January 2010)