Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis

BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT.

Left bundle branch area pacing:A new era of cardiac resynchronization therapy?

The recent systematic review and meta-analysis provided a comprehensive focus on the current state of cardiac resynchronization therapy(CRT).The authors determined the feasibility of physiological left bundle branch area pacing(LBBAP)in patients indicated for CRT through a careful analysis of trials.They found that LBBAP was associated with significant reductions in QRS duration,New York Heart Association functional class,B-type natriuretic peptide levels,and pacing thresholds as well as improvements in echocardiographic parameters compared to biventricular pacing.

Right ventricular septal pacing: Safety and efficacy in a long term follow up

AIM: To evaluate the safety and efficacy of the permanent high interventricular septal pacing in a long term follow up, as alternative to right ventricular apical pacing. METHODS: We retrospectively evaluated:(1) 244 patients(74 ± 8 years; 169 men, 75 women) implanted with a single(132 pts) or dual chamber(112 pts) pacemaker(PM) with ventricular screw-in lead placed at the right ventricular high septal parahisian site(SEPTAL pacing);(2) 22 patients with permanent pacemaker and low percentage of pacing(< 20%)(NO pacing);(3) 33 patients with high percentage(> 80%) right ventricular apical pacing(RVA). All patients had a narrow spontaneous QRS(101 ± 14 ms). We evaluated New York Heart Association(NYHA) class, quality of life(Qo L), 6 min walking test(6MWT) and left ventricular function(end-diastolic volume, LV-EDV; end-systolic volume, LVESV; ejection fraction, LV-EF) with 2D-echocardiography. RESULTS: Pacing parameters were stable duringfollow up(21 mo/patient). In SEPTAL pacing group we observed an improvement in NYHA class, Qo L score and 6MWT. While LV-EDV didn't significantly increase(104 ± 40 m L vs 100 ± 37 m L; P = 0.35), LV-ESV slightly increased(55 ± 31 m L vs 49 ± 27 m L; P = 0.05) and LV-EF slightly decreased(49% ± 11% vs 53% ± 11%; P = 0.001) but never falling < 45%. In the RVA pacing control group we observed a worsening of NYHA class and an important reduction of LV-EF(from 56% ± 6% to 43% ± 9%, P < 0.0001).CONCLUSION: Right ventricular permanent high septal pacing is safe and effective in a long term follow up evaluation; it could be a good alternative to the conventional RVA pacing in order to avoid its deleterious effects.

Can regadenoson pharmacologic SPECT be performed effectively in patients with left bundle branch block or paced rhythm patients? A retrospective comparison to adenosine SPECT

Purpose: Regadenoson (REG) is currently becoming the stress agent of choice in patients undergoing pharmacologic single photon emission computed tomography (SPECT). However, in patients with left bundle branch block (LBBB) and ventricular paced rhythm (VPR), hesitation exists amongst clinicians to use REG-SPECT due to the concern that the increased heart rate could cause false positive SPECT results. We sought to evaluate the comparability of A-SPECT and REG-SPECT in patients with LBBB and VPR. Methods: Retrospective study of 30 patients who served as their own controls. All 30 patients who underwent REG-SPECT (Grp 1) were compared to their prior A-SPECT (Grp 2) done within two years prior to REG-SPECT. Heart rate (HR) and blood pressure (BP) parameters, ECG, stress perfusion and gated variables, SPECT ischemia, and side-effects were evaluated. Statistical significance was set at P < 0.05. Results: Grp 1 and Grp 2 were comparable in hemodynamic parameters with increase in HR and decrease in systolic and diastolic BP with administration of adenosine and REG stress agents. However, there were no significant differences found in hemodynamic parameters and II degree AV block between the groups. All normal A-SPECT were found to be normal with REG-SPECT. No differences could be found between the two groups among SPECT parameters. Muscle pain was significantly higher in REG (10.0% vs. 0.0%, P = 0.083) and so was the use of aminophylline (16.7% vs. 0.0%, P = 0.025) to relieve the side-effect. Conclusion: REG-SPECT can be administered in patients with LBBB and VPR patients based on favorable and comparable hemodynamic responses and arrhythmia occurrences to A-SPECT. REG-SPECT can also be used for adequate interpretation of presence or absence of SPECT ischemia particularly in the LAD territory without any concern for false positive perfusion defects.

The Prevalence and Short-Term Outcomes of Ventricular Dyssynchrony after Right Ventricular Pacing

Objective: Long-term right ventricular pacing has been associated with an increased risk of heart failure and cardiomyopathy. The pathophysiology of cardiomyopathy associated with right ventricular pacing remains unclear. We aim to evaluate the burden and short-term outcomes of ventricular dyssynchrony after immediate permanent pacemaker implantation. Materials and Methods: This prospective cohort study examined consecutive patients who had permanent pacemaker implantation at Vajira Hospital in 2019. Left ventricular systolic function, specifically left ventricular ejection fraction (LVEF) and echocardiographic ventricular dyssynchrony parameters were assessed. The endpoints included the prevalence of ventricular dyssynchrony, new-onset cardiomyopathy, heart failure, and death. The correlation between QRS complex duration, the burden of ventricular pacing, and echocardiographic ventricular dyssynchrony was measured. Results: Thirty-six consecutive patients underwent pacemaker implantation. The prevalence of mechanical ventricular dyssynchrony was 22.2% using the interventricular conduction delay method, 41.7% using LV pre-ejection period method, and 11.1% using the septal posterior wall motion abnormality method. Electrical ventricular dyssynchrony was 86.1% and new-onset cardiomyopathy was 17.1% after 3 months of permanent pacemaker implantation. The right ventricular pacing of more than 20% was significantly associated with cardiomyopathy (p < 0.022) and heart failure (log-rank, p = 0.049) within 3 months. But heart failure was not associated with mechanical ventricular dyssynchrony parameters (log-rank, p = 0.610;hazard ratio [HR], 1.53;95% confidence interval [CI], 0.29 - 7.96;p = 0.613 for IVMD and log-rank, p = 0.398;HR, 0.04;95% CI, 0.01 - 3316.7 for SPWMD). Conclusion: Mechanical and electrical ventricular dyssynchrony are common findings in right ventricular pacing. High-burden right ventricular pacing after 3 months of permanent pacemaker implantation is often associated with cardiomyopathy and heart failure, but mechanical and electrical ventricular dyssynchrony does not predict a short-term decline in left ventricular systolic function and heart failure.

Dual-chamber pacing confers better myocardial performance and improves clinical outcomes compared to single-chamber pacing

The deleterious effects of long term right ventricular pacing are increasingly being recognized today.Current clinical practice favors the implantation of dual-chamber permanent pacemaker which maintains atrioventricular synchrony and is associated with better quality of life.However,despite the popular belief and common sense surrounding the superiority of dual-chamber pacing over single chamber pacing,the same has never been conclusively verified in clinical trials.Some observational evidence however,does exists which supports the improved cardiac hemodynamics,lower the rate of atrial fibrillation,heart failure and stroke in dual-chamber pacing compared to single-chamber pacing.In the index study by Haque et al,right ventricular pacing,particularly in ventricular paced,ven-tricular sensed,inhibited response and rate responsive pacemaker adversely im-pacted the left ventricular functions over 9-months compared to dual pacing,dual sensing,dual responsive and rate responsive pacemaker.Although there are key limitations of this study,these findings does support a growing body of evidence reinstating the superiority of dual chamber pacing compared to single chamber pacing.

左束支区域起搏与右心室间隔起搏技术对老年患者左心室收缩同步性、心功能的影响

目的探讨左束支区域起搏与右心室间隔起搏技术对老年患者左心室收缩同步性、心功能的影响。方法回顾性选取2022年2月至2023年3月期间于郴州市第一人民医院心血管内科接受永久性心脏起搏器植入术治疗的80例老年患者的临床资料,根据心脏起搏电极植入部位分为两组,即对照组、观察组各40例。对照组患者于右心室间隔处植入心脏起搏器,观察组患者于左束支区域植入心脏起搏器。分别于患者心脏起搏器植入术后1个月、术后6个月、术后12个月观察各指标变化,包括左心室收缩同步性参数[左心室收缩期纵向应变达峰时间标准差(time to peak longitudinal strain standard deviation,Tls-SD)、最大差值(time to peak longitudinal strain maximum difference,Tls-dif),左心室收缩期径向应变达峰时间标准差(time to peak radial strain standard deviation,Trs-SD)、最大差值(time to peak radial strain maximum difference,Trs-dif),左心室收缩期环向应变达峰时间标准差(time to peak circumferential strain standard deviation,Tcs-SD)、最大差值(time to peak circumferential strain maximum difference,Tcs-dif)]以及心功能指标[左心室射血分数(left ventricular ejection fraction,LVEF)、心排血量(cardiac output,CO)、心脏指数(cardiac index,CI)]、心腔大小[右心房内径(right atrial inner diameter,RAD)、左心房内径(left atrial diameter,LAD)、左心室舒张末期内径(left ventricular end diastolic diameter,LVEDD)、左心室收缩末期内径(left ventricular end systolic diameter,LVESD)]、氨基末端脑钠肽前体(N-terminal pro-brain natriuretic peptide,NT-proBNP)浓度等。于术后12个月测定起搏参数(感知、阈值、阻抗、心室起搏比例),并统计心脏起搏器植入术后12个月内心力衰竭再入院、死亡等不良事件发生情况。结果术后各时间点观察组心功能指标LVEF、CO、CI略高于对照组,但两组比较差异无统计学意义(P>0.05)。术后各时间点观察组心腔大小指标RAD、LAD、LVEDD、LVESD低于对照组,尤其是术后12个月[RAD:(36.63±2.22)mm vs.(40.13±1.61)mm,LAD:(31.09±1.14)mm vs.(38.32±1.08)mm,LVEDD:(49.76±3.22)mm vs.(54.63±3.14)mm,LVESD:(40.64±2.11)mm vs.(48.11±3.24)mm,P<0.05]。术后各时间点观察组左心室收缩同步性指标LSDI、Tls-SD、Tls-dif、Trs-SD、Trs-dif、Tcs-SD、Tcs-dif均低于对照组,尤其是术后12个月[LSDI:4.86%±0.83%vs.9.49%±0.48%,Tls-SD:(14.42±1.78)ms vs.(25.00±1.43)ms,Tls-dif:(50.92±4.53)ms vs.(90.17±8.41)ms,Trs-SD:(50.37±4.33)ms vs.(69.44±6.52)ms,Trs-dif:(141.03±15.64)ms vs.(179.04±18.42)ms,Tcs-SD:(37.85±3.41)ms vs.(48.10±4.62)ms,Tcs-dif:(130.09±14.53)ms vs.(158.09±18.57)ms,P<0.05]。术后各时间点观察组NT-proBNP浓度略低于对照组,但两组比较差异无统计学意义(P>0.05)。两组起搏程控参数起搏感知、阻抗比较,差异无统计学意义(P<0.05);观察组起搏阈值低于对照组[(0.66±0.10)V vs.(0.75±0.12)V,P<0.05];两组起搏程控参数起搏感知、阻抗、阈值均处于正常范围。观察组心室起搏比例低于对照组(43.23%±4.53%vs.73.43%±6.56%,P<0.05)。术后12个月观察组心力衰竭再入院发生率明显低于对照组,差异有统计学意义(5.00%vs.22.50%,P<0.05)。结论左束支区域起搏技术在改善永久性心脏起搏器植入患者左心室收缩同步性、心功能方面优于右心室间隔起搏技术,术后12个月不良事件发生率较低,更有利于保护心功能,起搏参数稳定,属于一种有效且安全的起搏技术。

判断左束支起搏成功夺获标准的研究进展

左束支起搏(LBBP)定义为起搏夺获左束支,包括左束支主干及其分支,伴或不伴周围心肌夺获,且夺获阈值一般不超过1.5 V/0.4 ms。记录到逆行希氏束电位或顺行左束支电位是左束支夺获的直接证据,但该操作较为复杂,临床使用较少。在起搏导线植入过程中,通常根据心电图变化来判断导线是否成功夺获左束支,具体包括体表心电图QRS波群形态、左心室达峰时间变化、腔内心电图检测到左束支电位或损伤电流,以及改变起搏输出时观察到非选择性LBBP转换到选择性LBBP或左心室间隔部起搏等。由于患者存在个体差异,一些学者提出了个体化的左心室达峰时间、V_(6)-V_(1)峰值间期以及LBBP评分等方法进一步补充了夺获标准。现对目前常用的标准进行分析总结,为临床操作提供更多依据,以提高LBBP手术成功率。

左束支区域起搏对房室传导阻滞患者术后新发房性心律失常的影响

目的探讨左束支区域起搏(left bundle branch area pacing,LBBaP)对房室传导阻滞(AVB)患者术后新发心房颤动(new-onset atrial fibrillation,NOAF)和心房高频事件(atrial high rate episodes,AHREs)的影响。方法回顾性纳入84例行起搏治疗的三度房室传导阻滞(ⅢAVB)患者,根据心室电极位置分为LBBaP组(n=42)和右室间隔部起搏(RVSP)组(n=42)。比较两组患者术前术后QRS波时限(QRSd)、心室起搏参数,并发症、脑卒中事件和NOAF、AHREs发生率。结果(1)LBBaP组术后NOAF、AHREs发生率均低于RVSP组(P<0.05)。(2)LBBaP组的p-QRSd短于RVSP组(P<0.05)。(3)两组患者心室起搏参数、并发症及脑卒中事件发生率之间差异无统计学意义(P>0.05)。结论相对于右室起搏,LBBaP术后AHREs、NOAF的发生率较低,可改善患者预后。

左心室室间隔瘢痕对左束支起搏术实现左束支夺获的影响

目的:通过心脏磁共振探索室间隔瘢痕对左束支起搏实现左束支夺获的影响。方法:回顾性分析52例拟接受左束支起搏的患者,根据是否实现左束支夺获分为失败组和成功组,并通过心脏磁共振对室间隔瘢痕分节段进行评分。结果:上室间隔瘢痕评分是预测左束支夺获成功与否的独立预测因子。当上室间隔的瘢痕<25%,左束支夺获的成功率为100%。而当瘢痕≥50%,左束支夺获的失败率为100%。结论:采用心脏磁共振评估上室间隔瘢痕有助于预测左束支起搏手术成功与否,为手术的顺利实施提供可靠的参考依据。

希浦系统起搏对心功能影响的研究进展

心脏起搏是心脏起搏、传导功能障碍及严重心力衰竭的有效治疗手段,但传统右心室起搏可增加心力衰竭、心房颤动发生率,双心室起搏具有相对较高的无应答率。近年来多项研究显示,希浦系统起搏作为生理性起搏新技术,起搏参数稳定,心脏同步性好。本文就目前希浦系统起搏对心功能影响的研究现状及进展进行综述,为促进希浦系统起搏技术发展提供理论依据。

希浦系统起搏对老年起搏诱导性心肌病病人效果的Meta分析

目的评估右心室起搏后,患起搏诱导性心肌病的老年病人升级至希浦系统起搏的临床疗效和安全性。方法在PubMed、Cochrane Library、Web of Science、Embase、中国知网、万方数据库、维普数据库检索希浦系统起搏对起搏诱导性心肌病疗效的相关文献,提取研究中有关临床获益和安全性的数据,在RevMan 5.4软件上进行Meta分析。结果共纳入8篇文献,包括185例病人,升级希浦系统起搏的成功率为95%。Meta分析结果显示:升级希浦系统起搏后,随访期间病人的左心室射血分数(MD=-11.73,95%CI:-14.74~-8.72,P<0.01)较升级术前提高,QRS波时限(MD=59.84,95%CI:55.98~63.70,P<0.01)较升级术前缩短,NYHA心功能分级(MD=1.05,95%CI:0.70~1.41,P<0.01)较升级术前明显降低,差异均有统计学意义。起搏阈值(MD=-0.11,95%CI:-0.24~0.02,P=0.08)和R波振幅(MD=-0.35,95%CI:-1.94~1.24,P=0.66)升级术前后差异无统计学意义。同时研究中观察到2例病人死亡。结论对于老年起搏诱导性心肌病病人,可考虑升级起搏方式为希浦系统起搏,不仅可以纠正长期右心室起搏引起的心脏电不同步和心室重塑,同时也能改善病人的临床心功能并减少手术相关并发症。

左束支起搏和右室心尖部起搏在老年房室传导阻滞患者中的临床疗效比较

目的比较左束支起搏(left bundle branch pacing,LBBP)和右室心尖部起搏(right ventricular apical pacing,RVAP)治疗老年房室传导阻滞(atrioventricular block,AVB)患者的临床效果。方法回顾性分析2016年1月—2021年6月因AVB于同济大学附属第十人民医院行永久起搏器植入术256例患者(≥65岁)的临床资料,根据起搏方式将患者分为RVAP组(n=121)和LBBP组(n=135)。比较两组起搏方式的临床疗效。结果两组患者基线资料均无明显统计学差异。两组患者的起搏参数(阈值、感知和阻抗)在术中、术后7 d、术后1年差异均无统计学意义(均P>0.05),但LBBP组患者术后QRS波群时限明显缩短(均P<0.001)。术后1年随访中,与RVAP组相比,LBBP组起搏术式显著改善患者心功能,如左室射血分数、左心室舒张末期内径、NT-proBNP表达水平(均P<0.05)。此外,LBBP组和RVAP组相比,并发症发生率和起搏器依赖患者比例无显著差异(均P>0.05),但LBBP患者术后1年内再住院率显著降低(P=0.004)。进一步行Logistic回归分析发现LBBP起搏术式与老年AVB患者的再住院率有关(全部进入模式P=0.014,向前逐步回归模式P=0.010)。Kaplan-Meier累积事件曲线的比较显示RVAP和LBBP的累积再住院率有显著统计学差异(P=0.003)。ROC曲线分析也揭示了不同起搏术式对老年AVB患者的再住院率有预测价值(P=0.011,AUC=0.703,灵敏度=0.857,特异度=0.550)。结论与传统RVAP相比,LBBP起搏术式治疗老年AVB患者具有更好的安全性和稳定性,可有效改善患者心功能,降低患者再住院率。

右心室不同部位起搏患者术后左心室收缩功能的变化

目的:探讨右心室不同部位起搏患者术后左心室收缩功能的变化。方法:收集本院2018年2月至2020年5月收治的95例需进行右心室起搏患者的临床资料,根据起搏部位的不同将其分为右室心尖部起搏(RVAP)组(n=47)以及右室间隔部起搏(RVSP)组(n=48)。比较两组起搏阈值、感知阈值、电极阻抗、左室舒张末期容积(LVEDV)、左室收缩末期容积(LVESV)、每搏量(SV)、左室射血分数(LVEF)。根据术后1年是否发生心功能不全,患者被分为心功能不全组(18例)和心功能正常组(77例),分析需右心室起搏患者发生心功能不全的影响因素。结果:与术后1周比较,术后1年RVAP组感知阈值[(11.51±1.21)mV比(12.11±0.81)mV]显著升高,P=0.004。与RVAP组比较,术后1年RVSP组LVESV[(25.32±7.63)ml比(29.77±12.36)ml]、LVEDV[(58.30±15.71)ml比(68.33±25.31)ml]、SV[(31.36±10.73)ml比(41.29±16.15)ml]均显著升高,LVEF[(60.55±8.76)%比(54.10±6.44)%]及心功能不全比例(27.66%比10.42%)显著降低,P<0.05或<0.01。非条件多因素Logistic回归模型分析显示,LVEF是需右心室起搏患者发生心功能不全的独立保护因素(OR=0.854,P=0.003),而RVAP、年龄≥60岁为其独立危险因素(OR=9.041、4.145,P=0.003、0.024)。结论:与右室心尖部起搏相比,右室间隔部起搏可显著改善每搏量,心功能不全发生率显著降低。

心肌代谢显像评价老年患者心室不同部位起搏的心室机械不同步性

目的应用心肌代谢显像评价心室不同部位起搏对左心室机械不同步性的影响。方法选择2023年1~11月复旦大学附属上海市第五人民医院行永久起搏器置入术的老年患者56例,随机分为左束支区域起搏(LBBAP)组和右心室起搏(RVP)组,各组28例,另选取28例未行起搏器置入术的老年患者作为对照组。起搏器置入术后1周内行^(18)F-氟代脱氧葡萄糖(^(18)F-FDG)正电子发射断层显像(PET)/CT心肌代谢显像,进行PET心肌代谢影像分析和左心室机械同步性评价。结果对照组患者左心室射血分数(LVEF)显著高于LBBAP组和RVP组[(67.68±9.61)%vs(62.71±11.33)%vs(57.36±16.07)%,P=0.012];LBBAP组与RVP组LVEF比较无显著差异(P>0.05)。与RVP组比较,LBBAP组角度标准差(PSD)、相位带宽、熵、室壁运动总评分(SMS)、室壁增厚总评分(STS)、室壁运动异常范围占中段心肌表面积的百分比(Mot Ext)、室壁增厚异常范围占中段心肌表面积的百分比(Thk Ext)显著降低,差异有统计学意义(P<0.01)。LBBAP组与对照组PSD、相位带宽、熵、SMS、STS、Mot Ext、Thk Ext等比较差异无统计学意义(P>0.05)。结论^(18)F-FDG PET/CT心肌代谢显像对心室不同部位起搏进行左心室机械同步性评价显示,LBBAP左心室同步性参数优于RVP,与对照组相近。

巨大心脏TAVR中应用左心室导丝起搏技术1例

1临床资料患者男,74岁。因“反复胸闷气促45年,加重3 d”于2023年6月8日入广东省中医院。患者45年前出现胸闷、气促,伴心悸,诊断为风湿性心脏病行二尖瓣瓣膜置换术,维持华法林等药物治疗。2015年6月诊断为心房颤动伴长R-R间期行单腔永久起搏器植入术,2021年3月起搏器程控提示电量耗竭,植入Micra无导线起搏器,期间冠脉造影未见冠脉病变。

左束支区域起搏对心室起搏患者心脏功能、血浆BNP水平及心律失常发生率的影响

目的 探讨左束支区域起搏(LBBP)对心室起搏患者心脏功能、血浆B型脑钠肽(BNP)水平及心律失常发生率的影响。方法 回顾性分析2021年5月至2023年5月就诊于石家庄市人民医院的62例需心室起搏的患者,按心脏起搏电极植入部位不同分为LBBP组(32例)和右心室间隔部起搏(RVSP)组(30例),比较两组心脏功能[左心室射血分数(LVEF)、左心房容积指数(LAVI)、三尖瓣环收缩期位移(TAPSE)、二尖瓣环处舒张早期峰值流速(Ea)、二尖瓣口舒张早期的血流峰值速度(E)与二尖瓣环舒张早期峰值速度(Ea)的比值(E/Ea)]、起搏参数及QRS波时限、血浆BNP和6 min步行试验(6-MWT)和心律失常发生率。结果 术后6个月,RVSP组LVEF、TAPSE相比术前RVSP组和术后6个月LBBP组均降低(P<0.05),术后6个月RVSP组LAVI、E/Ea相比术前RVSP组和术后6个月LBBP组均升高(P<0.05)。术后1周、术后1个月、术后6个月LBBP组和RVSP组起搏参数(阈值、感知、阻抗)比较均无明显差异(P>0.05)。术后1周、术后1个月、术后6个月LBBP组QRS波时限均低于RVSP组(P<0.05)。两组术后心律失常发生率比较差异不明显(P>0.05)。结论 与RVSP相比,LBBP应用于心室起搏患者可有效降低术后血浆BNP水平和QRS波时限,有助于心脏功能的改善。

Left ventricular endocardial pacing predicts the reduction of left ventricular outflow tract pressure gradient immediately after percutaneous transseptal myocardial ablation in patients with hypertrophic obstructive cardiomyopathy refractory to medicatio

Background Hypertrophic obstructive cardiomyopathy （HOCM） carries an increased risk for sudden cardiac death. No data regarding the percutaneous transseptal myocardial ablation （PTSMA） and epicardial left ventricular pacing （LVP） were reported. Methods Seven patients with recurrent symptoms and increased resting left ventricular outflow tract pressure gradient （LVOTG） after PTSMA and another 14 patients with HOCM without history of PTSMA were studied. Both resting and dobutamine stress echocardiography, PTSMA and LVP were routinely performed. Results In patients without previous PTSMA procedure, mild reduction of resting LVOTG was detected at 5 minutes after left ventricular pacing, and this reduction became significant at 10 minutes. All patients were divided into successful and unsuccessful groups according to their response to LVP. In contrary to patients in unsuccessful group, resting and R-S2 stimuli-induced LVOTG during PTSMA procedure were decreased dramatically （（9±5） mmHg vs （58±12） mmHg, （12±2） mmHg vs （113±27） mmHg, P〈0.001）. Analysis of Logistic regression demonstrated that only LVOTG level dudng left ventdcular pacing was an independent factor predicting the reduction of LVOTG immediately after PTSMA （odds ratio （OR）, 0.59; 95% CI 2.67 to 5.82; P=0.0002）. Conclusion Left ventricular endocardial temporary pacing plays a critical role in predicting acute effect on the reduction of LVOTG immediately after PTSMA procedure.

经房间隔穿刺左心室内膜起搏心脏再同步化治疗并文献分析

目的总结经穿刺房间隔植入左心室心内膜电极行心脏再同步化(CRT)治疗的方法和临床疗效。方法 2014年3-8月2例非缺血性心肌病患者在中南大学湘雅医院行穿房间隔植入左心室内膜电极CRT治疗。局部麻醉下经右股静脉穿刺房间隔,再经左锁骨下静脉经房间隔穿刺口送起搏导线入左心室行左室内膜起搏完成CRT植入术。通过查询Medline、EMBASE、CNKI、VIP和万方数据库等总结目前该技术开展的现状。结果1例患者成功植入左心室内膜起搏电极完成CRT术。随访9月,患者症状明显改善,无并发症发生。1例患者穿刺房间隔后因电极无法通过穿刺口而无法完成CRT术。文献分析示共101例患者通过上/下静脉混合法或单纯经下腔/上腔静脉途径穿刺房间隔实施该手术;采用射频消融大头电极、可控弯鞘、圈套器或心脏三维标测系统辅助将电极经房间隔送入左心室内;或经股静脉与上腔静脉建立轨道将电极拉出。患者术后心功能改善。2例患者早期出现电极脱位;2例出现TIA;4例出现囊袋积血。结论尽管操作难度大,对于无法经冠状静脉窦植入左心室起搏电极的CRT治疗的患者,经穿刺房间隔植入左心室心内膜电极起搏行CRT治疗是一种疗效较好、安全的方法。

双腔起搏器心室自身优先功能对病态窦房结综合征患者左心功能的影响

选择因病态窦房结综合征安装DDD心脏起搏器的患者31例。根据植入后是否开启心室自身优先(VIP)功能分为对照组(n=15)与观察组(n=16),随访起搏器参数,并观察累计心室起搏比例(Cum%VP)、左房内径(LAD)、左室舒张末期内径(LVEDD)、左室射血分数(LVEF)及6 min步行试验距离的变化。起搏器植入术后12个月,观察组与对照组比较Cum%VP比例明显降低(P<0.01);LVEDD显著减少(P<0.01);6 min步行试验距离显著增加(P<0.05)。DDD心脏起搏器VIP功能可以显著减少累计心室起搏比例,从而更好的保护左心功能。