Echocardiographic mapping of left ventricular resynchronization during cardiac resynchronization therapy procedures

Background Cardiac resynchronization therapy (CRT) is an effective electrical therapy for patients with moderate to severe heart failure and cardiac dyssynchrony. This study aimed to investigate the degree of acute left ventricular (LV)resynchronization with biventricular pacing (BVP) at different LV sites and to examine the feasibility of performing transthoracic echocardiography (TTE) to quantify acute LV resynchronization during CRT procedure.Methods Fourteen patients with NYHA Class ⅢⅣ heart failure, LV ejection fraction ≤35%, QRS duration ≥120 ms and septal-lateral delay (SLD) ≥60 ms on tissue Doppler imaging (TDI), underwent CRT implant. TDI was obtained from three apical views during BVP at each accessible LV site and SLD during BVP was derived. Synchronicity gain index (Sg) by SLD was defined as (1+(SLD at baseline - SLD at BVP)/SLD at baseline).Results Seventy-two sites were studied. Positive resynchronization (R+, Sg>1) was found in 42 (58%) sites. R+ was more likely in posterior or lateral than anterior LV sites (66% vs. 36%, P <0.001). Concordance of empirical LV lead implantation sites and sites with R+ was 50% (7/14).Conclusions The degree of acute LV resynchronization by BVP depends on LV lead location and empirical implantation of LV lead results in only 50% concordance with R+. Performing TTE during CRT implantation is feasible to identify LV sites with positive resynchronization.     

Echocardiographic mapping of left ventricular resynchronization during cardiac resynchronization therapy procedures

Background Cardiac resynchronization therapy （CRT） is an effective electrical therapy for patients with moderate to severe heart failure and cardiac dyssynchrony. This study aimed to investigate the degree of acute left ventricular （LV） resynchronization with biventricular pacing （BVP） at different LV sites and to examine the feasibility of performing transthoracic echocardiography （TTE） to quantify acute LV resynchronization during CRT procedure. Methods Fourteen patients with NYHA Class Ⅲ-Ⅳ heart failure, LV ejection fraction 〈35%, QRS duration 〉120 ms and septal-lateral delay （SLD） 〉60 ms on tissue Doppler imaging （TDI）, underwent CRT implant. TDI was obtained from three apical views during BVP at each accessible LV site and SLD during BVP was derived. Synchronicity gain index （Sg） by SLD was defined as （I＋（SLD at baseline - SLD at BVP）/SLD at baseline）. Results Seventy-two sites were studied. Positive resynchronization （R＋, Sg〉1） was found in 42 （58%） sites. R＋ was more likely in posterior or lateral than anterior LV sites （66% vs. 36%, P 〈0.001）. Concordance of empirical LV lead implantation sites and sites with R＋ was 50% （7/14）. Conclusions The degree of acute LV resynchronizaUon by BVP depends on LV lead location and empirical implantation of LV lead results in only 50% concordance with R＋. Performing l-rE during CRT implantation is feasible to identify LV sites with positive resynchronization.     

女性患者心脏再同步化治疗

研究证实,心脏再同步化治疗(CRT)能够改善心衰患者心脏功能,提高生存率,减少终点事件.虽然目前缺少大型前瞻性随机对照临床试验,但现有的大部分数据显示,女性患者CRT术后获益大于男性,且女性是CRT获益的独立预测因素.本文就女性患者CRT的应用及疗效进行综述,便于了解女性患者CRT的特点.     

心脏再同步化治疗中的心电重构

背景：需要更多的资料以确定接受心脏再同步化治疗患者的心电和结构逆向重构之间的关系。方法：观察20例重度药物难治性心力衰竭患者（左心室射血分数〈40％且QRS波群时间〉120ms）在植入双心室（BiV）起搏器之前和之后3个月时不同起搏模式下的QRS波群时间和JT间期；采用超声心动图评价结构重构。结果：急性期（P=0．002）和3个月时（P=0．007），BiV起搏下QRS波群时间显著缩短，JT间期无显著变化。3个月时BiV起搏所致QRS波群时间缩短的程度与收缩末期容量和舒张末期容量的降低呈中度相关（分别为r=0．53，P：0．016和r=0．45，P=0．045），与左室射血分数的增加也呈中度相关（r=0．49，P=0．028）。观察到右心室（RV）起搏时的QRS波群增宽在BiV起搏3个月后更为明显（就急性期测值而言），提示起搏介导再同步一段时间后，起搏介导的心电失同步增强。结论：Biv起搏介导的QRS波群时间缩短程度表现为与结构逆向重构相关（就收缩末期容量减低而言）。接受CRT治疗的所有病例中，急性期变化和出现在中期的重构过程并不包括JT间期。起搏介导再同步一段时间后可能加重潜在的RV起搏所致心电失同步。     

QT间期离散度(QTd)对心脏同步化治疗评估研究

目的:观察心脏再同步治疗(CRT)对心肌复极离散的影响。方法:选取68例接受CRT植入的心力衰竭患者,根据术后6个月左心室射血分数绝对值是否较基线水平升高绝对值是否较基线水平提高≥10%,分为反应组(n=34)和无反应组(n=34)。比较两组患者CRT植入后不同时期QRS间期、QT间期复极离散度指标变化情况。结果:反应组患者术后1年QRS间期和QTd间期较术前和术后<24 h均明显缩短,差异有统计学意义(P<0.05),而无反应组各时期上述指标差异均无统计学意义,差异有统计学意义(P>0.05);68例患者中,CRT术后有22例出现室性心律失常,QTd间期在室性心律失常组较非室性心律失常组明显延长,差异有统计学意义(P<0.05)。结论:QTd在对CRT治疗患者术后的有效性是很好的评价指标。     

Atrioventricular intrinsic conduction and cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is a major breakthrough in therapy for patients with advanced congestive heart failure, however, a number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to CRT. These issues are also relevant to patients who do respond to CRT as potentially their response might be further increased. Though patients do not respond to CRT because of many known postulated reasons, we review the importance of maintaining atrioventricular intrinsic conduction during CRT in this paper, which maybe is one of methods to reduce the rates of non-response to CRT.     

心脏再同步化治疗患者术后反应的比较研究

目的回顾分析心脏再同步化治疗（CRT）患者抗心衰药物的治疗变化,指导术后规范用药。方法选取102例CRT治疗患者随访数据,根据术前和末次随访记录的左室舒张末期内径（LVEDD）,左心室射血分数（LVEF）和纽约心功能分级（NYHA）将患者分为有反应组和无反应组;分析两组的血管紧张素转换酶抑制剂／血管紧张素受体拮抗剂（ACEI／ARB）、β受体阻滞剂、利尿剂和地高辛等药物使用变化情况。结果86例患者归入有反应组,16例患者归入无反应组。有反应组术后ACEI／ARB应用剂量明显增加（84比56）,β受体阻滞剂也明显增加（86比60）,利尿剂无明显变化（85比80）,地高辛也无明显变化（82比81）;无反应组术后A—CEI／ARB应用剂量患者明显减少（13比4）,β受体阻滞剂量也明显减少（10比5）,利尿剂无明显变化（16比16）,地高辛也无明显变化（15比16）。ACEI／ARB＋β受体阻滞剂剂量均增加组和单药组比较,NYHA心功能分级改善、LVEDD缩小及LVEF提高更为显著。结论慢性充血性心力衰竭患者CRT术后应及时调整药物治疗方案,CRT治疗能提高抗心衰药物的效果。     

心脏再同步治疗中电极起搏部位和模式

心脏再同步治疗(CRT)与传统起搏治疗在适应证和植入技术上有很大不同.CRT治疗伴有收缩不同步的心衰患者,通常需要经静脉植入3根电极导线.其中通过冠状静脉窦植入左室电极导线来起搏左室,其起搏部位在CRT治疗中起相当重要的作用.有时还需寻求其它起搏模式,比如经胸植入左室电极导线来弥补冠状窦和静脉分支解剖所造成的治疗局限.除此之外,对右房、右室电极导线部位及起搏模式在CRT治疗中所起的作用也在进行各种优化探索.     

慢性心衰心脏再同步化治疗：疗效优化策略

心脏再同步化治疗(cardiac resynchronization therapy,CRT)已成为慢性心衰非药物治疗的重要手段,临床应用显示仍有30%左右的患者无反应。本文综述了影响CRT疗效的主要因素,并进一步阐述了优化CRT疗效的策略,包括优化适应证、优化左室导线植入部位、术后CRT参数的程控优化、药物优化以及采用新的起搏模式。     

双心室再同步治疗充血性心力衰竭的临床研究

目的　探讨双心室再同步治疗充血性心力衰竭的疗效。方法　所选择患者均为心功能Ⅲ～Ⅳ级 ,左心室舒张末期内径 >60mm ,EF值 <3 5 % ,E、A峰融合 ,二尖瓣中等度以上返流 ,完全性左束支传导阻滞 ,QRS时限 >14 0ms。应用Insync 80 40三腔起搏器 ,起搏电极定位于右心耳、右心室心尖部、冠状静脉窦左侧支或侧后分支。术后以VAT方式起搏。结果　例 1随诊 6个月 ,例 2随诊 1个月 ,2例术后心功能均提高至Ⅱ级 ,EF值明显提高 (例 1,2 1%VS3 0 % ;例 2 ,2 7%VS 3 8% ) ,QRS波时限明显缩短 (例 1,2 0 0msVS 110ms ;例 2 ,180ms ;例 2 ,VS 13 0ms) ,术后经心脏超声优化A—V间期 ,90ms时E、A峰分离程度最大 ,二尖瓣返流明显减少。例 1,术后 6个月左心房及左心室舒张末期内径无明显缩小。例 2 ,术后 1个月左心房 ( 4 3mmVS 3 5mm)及左心室舒张末期内径 ( 92mmVS 85mm)缩小明显。结论　双心室再同步治疗充血性心力衰竭近期疗效满意 ,是值得深入研究的新方法。     

心脏再同步化治疗心力衰竭的Meta分析

目的:评价心脏再同步化治疗(伴或不伴除颤功能)在降低心力衰竭患者的死亡率方面的作用.方法:查阅已公开发表的有关心脏再同步化治疗心力衰竭的临床随机对照试验文献,以死亡率为主要评价指标,用Cochrane协作网的软件RevMan5.1进行Meta分析.结果:本次分析最终纳入文献12篇(n=7 539).与单纯药物治疗组相比...     

左心室四极导线在心脏再同步治疗中的临床应用

目的：评估左心室四极导线在心脏再同步治疗中的临床应用。方法选择符合心脏再同步治疗（CRT）适应证患者30例,分为左心室四极导线组和双极导线组。比较两组在临床疗效、同步性、手术时间及并发症等方面的差异。结果两组患者左室导线置入时间、手术时间、X 线曝光时间、左室导线位置均无显著差异。四极导线组可选择的起搏向量远多于双极导线组。术后1个月的超声优化程控显示,四极导线组优化后主动脉射血速度时间积分（AOVTI）和左室同步性均显著改善,同时优于双极导线组优化后（P ＜0．05）。随访至术后6个月,四极导线组的左室射血分数优于双极导线组（P ＜0．05）。结论左心室四极导线与双极导线具有同样的安全性,其血液动力学、同步性和短期临床疗效优于双极导线,并可能有助于减少膈神经刺激避免二次手术等并发症。     

Potential predictors of non-response and super-response to cardiac resynchronization therapy

Background  Although cardiac resynchronization therapy (CRT) is already an established treatment, the characteristics of patients who have an excellent response to CRT and those who get no benefit remain to be determined. The purpose of this study was to search for potential predictors of both non-response and super-response to CRT.

Methods  Seventy-six consecutive patients who received CRT treatment were divided into group A (non-responders), group C (super-responders) and group B (responders exclusive of super-responders). Student’s t test, Mann-Whitney test, Logistic regression and receiver operating characteristic curve were employed to identify potential predictors among the patients’ demographic characteristics, clinical features, several electrocardiographic parameters before and after CRT implantation, and their pre-implant echocardiographic parameters.

Results  Group A had the lowest 3-month left ventricular ejection fraction (LVEF). Group C had the smallest pre-implant left ventricular end-diastolic dimension (LVEDD), the shortest post-implant QRS duration, the smallest 3-month LVEDD and the highest 3-month LVEF. In addition, there was a trend of gradual change in percent of left bundle branch block, severity of pre-implant mitral regurgitation, pre-implant QRS dispersion, post-implant QRS duration as well as post-implant QRS dispersion from group A to group B and from group B to group C. Multivariable Logistic analysis revealed that only pre-implant LVEDD could predict CRT super-response. A pre-implant LVEDD of 68.5 mm was the cut-off value that identified super-responders with 87.5% sensitivity and 79.7% specificity. A pre-implant LVEDD of 62.5 mm identified super-responders with 50.0% sensitivity and 89.8% specificity.

Conclusions  Predictors of a CRT non-response remain unclear at present. But it is credible that patients with a smaller left ventricle would have a better chance to become super-responders to CRT.

     

三腔起搏复律除颤器植入1例

患者，男，82岁。因间断胸闷、呼吸困难2年，加重1d入院。既往有高血压、陈旧前壁心肌梗死病史。入院查体：血压140／90mmHg（1mmHg=0．1333kPa），双肺底部对称性细湿罗音，心界向左下扩大，HR40次／min，律齐，心音低钝，二尖瓣区轻度收缩期杂音，双下肢轻度水肿。心电图示：窦性心律，QRS宽度120～140ms，V1～V4病理Q波，广泛导联ST—T改变。     

Application of echocardiography in resynchronization treatment of heart failure patients

Objective  To review the updated research progress about the application of echocardiography in resynchronization treatment of chronic heart failure patients.

Data sources  The data used in this review were from PubMed, published in English and using the key terms “heart failure”, “echocardiography” and “cardiac resynchronization therapy”.

Study selection  Relevant articles were reviewed and selected to address the stated purpose.

Results Increasing numbers of studies have suggested the importance of echocardiography in resynchronization treatment of chronic heart failure patients. Echocardiography can evaluate atrioventricular, inter- and intra-ventricular mechanical dyssynchrony before cardiac resynchronization therapy (CRT), as a guidance to assess the optimal left ventricular (LV) pacing location, optimize the atrioventricular and interventricular delays and predict response to CRT.

Conclusions  Echocardiography is both non invasive and easily repeatable, and plays a crucial role in appraisal of heart synchronism, instruction of actuator placement, optimization of the device procedure, and prediction of the response to CRT.

     

Cardiac resynchronization therapy and B-type natriuretic peptide in heart failure

Cardiac resynchronization therapy （CRT） improves left ventricular function, symptom status, quality of life and reduces hospitalization and mortality in patients with New York Heart Association （NYHA） Class Ⅲ or Ⅳ heart failure and intraventricular conduction delay despite optimal medical management. B-type natriuretic peptide （BNP） and its amino terminal cleavage equivalent （NT-pro BNP） levels correlate with the severity of heart failure and predict prognosis of heart failure patients. In this issue of the journal, the study reported by Ding et al found that percentage change in NT-pro BNP levels from baseline to 3 months was a strong predictor for long-term response to CRT. These investigators studied 44 patients with NYHA class Ⅲ or Ⅳ heart failure and wide QRS （〉120 ms）.     

Optimized cardiac resynchronization therapy in patients with congestive heart failure

Heart failure was a major and increasing public health problem, with an almost ＂epidemic＂ increase in the number of patients. Despite recent advances in pharmacotherapy, the prognosis remains poor. Cardiac resynchronization therapy （CRT）, by pacing right and left ventricles, has been proved to improve symptoms and reduce mortality for heart failure patients with cardiac dyssynchrony, However, 20% to 30% of patients did not respond to CRT. The good cardiac synchronicity before CRT and the remaining atrioventficular, inter- and intra-ventricular dyssynchrony after CRT may explain the non-response. New echocardiographic techniques, and in particular tissue Doppler imaging （TDI） analysis, has been proved to be a helpful tool in evaluating cardiac dyssynchrony, as well as in assessing the degree of cardiac resynchronization after biventricular device implantation. So, in this study, we optimized the pacing parameters to determine whether echo-guided optimizing of AV/VV delays would enhance the effect of CRT on cardiac function and synchronicity.     

Analysis of cardiac resynchronization therapy in right ventricular pacing patients

To the editor:According to an investigaion of 417 tertiary hospitals of recent ten years in China,pacemaker implantation has been raising at an average of 11％ per year.Overwhelming majority were received right-side DDD pacemaker.There are a great part need cardiac resynchronization therapy (CRT),especially when they had got cardiomyopathy and/or heart failure.No definite guidelines were for how to upgrade the resynchronization system in these patients.Here we provide one practical way in one case.