心脏再同步化治疗与心力衰竭患者的心脏电学逆重构

目的探讨心脏再同步化治疗(CRT)是否会纠正心力衰竭患者的电重构现象。方法回顾分析伴有完全性左束支传导阻滞的心力衰竭患者接受CRT后随访观察1年,分别在术中电极安置后和术后1年测试自身心律下右室-左室电极的激动时间差(△t),右室电极刺激到左室电极感知时间(RVp-LV)及左室电极刺激到右室电极感知时间(LVp-RV),比较CRT应答者与无应答者的自身QRS波时限、双室起搏下QRS波时限和△t、RVp-LV、LVp-RV。结果共入选51例,应答组(36例),无应答组(15例)。应答组术前和术后1年相比,△t和RVp-LV缩短(P0.05)。无应答组术前与术后1年比较,△t、RVp-LV延长(P0.05)。两组自身QRS波时限无差异,但术后1年无应答组起搏下QRS波时限延长。结论 CRT应答患者发生了电学逆重构。起搏QRS波时限改变与CRT疗效有关。     

左室电极起搏位置与心脏再同步化治疗的疗效

目的探讨左室电极在左室游离壁不同位置起搏对慢性心力衰竭(简称心衰)心脏再同步化治疗(CRT)患者远期疗效的影响。方法 110例扩张型心肌病或高血压病合并慢性左心衰患者均符合CRT植入指征而接受CRT术,术后根据后前位和左前斜位的胸部X线影像,左室电极导线植入部位分为前壁、侧壁、后壁和后基底部。术后12个月,分别查心脏超声、心电图等,分析心功能、心电图QRS波时限和左室射血分数(LVEF)及左室容积变化。以心功能(NYHA)分级至少改善1级或LVEF升高25%以上定义为有效。结果由于患者心脏静脉变异和组织超声多普勒检查结果,左室电极导线分别被植入前壁4例、侧壁68例和后壁37例、后基底部1例。术后3例因心功能恶化死亡,2例发生猝死,1例术后第9天因肺部感染死亡。术后12个月,104例生存者中,有效91例,无效13例,总有效率87.5%。左室电极位于侧壁组的有效率(92.4%)明显高于后壁组(85.7%)(P<0.05)。前壁或后基底部的5例均无效。结论 CRT对慢性心衰患者有效,其疗效与左室电极起搏位置密切相关,左室侧壁或后壁是左室电极导线的理想起搏部位。     

心外膜电极导线在心脏再同步左室起搏中的应用(附二例报道)

目的报道2例心外膜电极导线在心脏再同步治疗(CRT)左室起搏中的应用及结果。方法2例均因心脏靶静脉解剖结构问题不能经心脏静脉途径置入左室电极,其中1例为右室双部位(心尖部+流出道间隔)起搏3个月后无效的患者。全麻后气管插管,在左第4肋间腋前线处切口,进胸后切开心包,用缝线将心外膜电极固定于左室侧后下壁,通过皮瓣下隧道把左室电极送入囊袋并与脉冲发生起搏器左室孔相联。结果2例手术顺利,无并发症。术后左室同步性明显好转,射血分数增加,心功能改善。结论心外膜导线在CRT左室起搏中的应用是安全、可行的,术后短期随访可获得良好的临床疗效。     

双心室再同步治疗的长期病死率与无应答

目的 CRT治疗减少心衰的住院率及病死率,但有20%～30%的患者对CRT无应答。我们目的是观察本中心双心室再同步治疗(CRT)术后长期病死率及无应答的发生率,并分析可能导致无应答的原因。方法 2001年3月～2009年5月119例患者行CRT治疗(男96例,年龄34～82岁)。NYHA心功能Ⅲ级～Ⅳ级,左室射血分数(LVEF)≤35%,随访6个月～8年。CRT应答的判定标准为CRT植入术后6个月NYHA心功能改善≥1级及6-MWT增加≥25%,或LVEF增加≥15%。结果 119例患者中,7例在CRT植入后6个月内因不同原因死亡,112例完成6个月以上的随访。总病死率为21.01%,心源性死亡16例,非心源性死亡9例。因心衰进展死亡5例,猝死9例。全因死亡率及心衰恶化导致死亡率CRT无应答组均明显高于应答组(28.12%vs 13.75%,P<0.05;12.5%vs0,P<0.01)。无应答发生率为28.57%。无应答组心衰病程明显长于CRT应答组(P<0.05),其肺动脉压力及血清肌酐(SCr)值也均高于CRT应答组(P<0.05)。无应答组左心室电极导线置入位置在非理想靶血管(心大静脉及心中静脉)明显多于CRT应答组(P<0.05)。多因素Logistic回归分析提示心衰病程、肺动脉高压、SCr值增高、完全性右束枝传导阻滞(RBBB)及心室电极导线置入位置均是CRT无应答的独立危险因素。结论 CRT术前心衰病程、肺动脉高压及SCr值增高均是CRT无应答的独立危险因素。RBBB虽然也有QRS时限明显增宽,但CRT术后无应答的发生率明显增高。左室电极导线的位置是决定CRT术后无应答发生的重要环节,心大静脉不宜做左室电极导线置入的部位。缺血性心肌病血运重建是影响CRT疗效不可忽视的问题之一。     

双心室再同步治疗的长期病死率与无应答

目的 CRT治疗减少心衰的住院率及病死率,但有20%～30%的患者对CRT无应答。我们目的是观察本中心双心室再同步治疗(CRT)术后长期病死率及无应答的发生率,并分析可能导致无应答的原因。方法 2001年3月～2009年5月119例患者行CRT治疗(男96例,年龄34～82岁)。NYHA心功能Ⅲ级～Ⅳ级,左室射血分数(LVEF)≤35%,随访6个月～8年。CRT应答的判定标准为CRT植入术后6个月NYHA心功能改善≥1级及6-MWT增加≥25%,或LVEF增加≥15%。结果 119例患者中,7例在CRT植入后6个月内因不同原因死亡,112例完成6个月以上的随访。总病死率为21.01%,心源性死亡16例,非心源性死亡9例。因心衰进展死亡5例,猝死9例。全因死亡率及心衰恶化导致死亡率CRT无应答组均明显高于应答组(28.12%vs 13.75%,P<0.05;12.5%vs0,P<0.01)。无应答发生率为28.57%。无应答组心衰病程明显长于CRT应答组(P<0.05),其肺动脉压力及血清肌酐(SCr)值也均高于CRT应答组(P<0.05)。无应答组左心室电极导线置入位置在非理想靶血管(心大静脉及心中静脉)明显多于CRT应答组(P<0.05)。多因素Logistic回归分析提示心衰病程、肺动脉高压、SCr值增高、完全性右束枝传导阻滞(RBBB)及心室电极导线置入位置均是CRT无应答的独立危险因素。结论 CRT术前心衰病程、肺动脉高压及SCr值增高均是CRT无应答的独立危险因素。RBBB虽然也有QRS时限明显增宽,但CRT术后无应答的发生率明显增高。左室电极导线的位置是决定CRT术后无应答发生的重要环节,心大静脉不宜做左室电极导线置入的部位。缺血性心肌病血运重建是影响CRT疗效不可忽视的问题之一。     

左束支传导阻滞伴心力衰竭患者心脏再同步化治疗无应答影响因素分析

目的分析心脏再同步化治疗左束支传导阻滞(LBBB)伴心力衰竭无应答的影响因素,为临床改进LBBB伴心力衰竭患者的心脏再同步化(CRT)治疗方案提供理论依据。方法选取2013年3月至2017年12月于河南省人民医院心血管内科接受CRT治疗的21例LBBB伴心力衰竭无应答患者(研究组)和同期40例应答患者(对照组)作为研究对象,收集两组患者详细资料,进行单因素分析和独立危险因素分析。结果单因素分析结果显示QRS波时限、脑钠肽水平、左房容积、左室容积、右房容积、起搏部位、二尖瓣反流量、房颤、高血压均与CRT治疗LBBB伴心力衰竭无应答存在明显相关性(P0.05),危险因素分析显示QRS波时限、起搏部位、二尖瓣反流量、房颤、高血压均为导致患者疗效不佳的独立危险因素(P0.05)。结论 QRS波时限、左心室电极起搏部位、二尖瓣反流量、房颤均是LBBB伴心力衰竭患者CRT治疗无应答的独立危险因素,术前优化患者选择,术中优化左室起搏部位,并结合术后起搏参数的优化控制,能够提高患者CRT治疗应答率,降低费效比。     

左室起搏电极部位对心脏再同步化治疗疗效的影响

目的探讨左室起搏电极部位对心脏再同步化治疗(CRT)效果的影响。方法 121例慢性心功能不全患者接受CRT,其中93例将左室电极植入侧后静脉、侧静脉或后静脉(A组),另16例植入心中静脉(B组)、12例植入心大静脉(C组);所有患者术前及术后6个月行纽约心功能(NYHA)分级,常规心电图及超声心动图检查。结果 A组患者术后NYHA分级得到显著改善,QRS波时限变窄,左室射血分数显著提高,左室舒张末内径、左室收缩末内径显著缩小(P<0.01);B组患者超声心动图部分指标及QRS波时限显著改善,但其NYHA分级无显著改变;而C组患者术后各项指标均无显著改善(P>0.05)。结论 CRT时应尽可能将左室电极置于左室侧壁或侧后壁。     

初期开展心脏再同步化治疗慢性心力衰竭的效果及技术难点

目的总结分析初期开展心脏再同步化治疗(CRT)慢性心力衰竭(简称心衰)的效果及技术问题。方法对20例植入CRT/CRTD的患者观察术前、术后6个月的心功能指标,描述左室电极的植入过程,随访患者预后。结果术后6个月有关心功能指标均明显改善(P均<0.01),随访32.9±21.9个月,死亡4例,其中1例猝死,3例非心脏原因死亡。左室导线进入冠状窦失败改为右室双位点起搏2例(2/20,10%),左室导线难以固定于靶静脉改为经心中静脉与靶静脉吻合支1例(1/20,5%),冠状静脉阶段性狭窄1例(1/20,5%),术后导线脱位3例(3/20,15%)均成功复位。术前冠状动脉造影/冠状静脉显影9例(9/20,45%),术中测试左室电极刺激膈肌跳动经调整电极位置均可避免。结论 CRT治疗心衰有效;术前冠状动脉/冠状静脉造影对指导和易化左室导线植入有益。右室双位点起搏改善心衰不明显,适当调整电极可避免膈肌刺激。     

双心室再同步治疗后无应答发生率及原因分析

目的 观察本中心双心室再同步治疗(CRT)术后无应答的发生率,并分析可能导致无应答的原因.方法 2001年3月至2009年5月119例患者行CRT治疗(男96例,年龄34～82岁),NYHA心功能Ⅲ～Ⅳ级,左心室射血分数≤35%,随访6个月以上.结果 119例患者中,7例在CRT置人后6个月内因不同原因死亡,112例完成6个月以上的随访,无应答发生率为28.57%.多因素logistic回归分析提示心力衰竭病程、肺动脉高压、血清肌酐值增高、完全性右束支传导阻滞及心室电极导线置人位置均是CRT无应答的独立危险因素.在CRT术后6个月时,CRT应答组心力衰竭的常规治疗药物明显减少,主要是洋地黄和利尿剂与无应答组比较差异有统计学意义(P＜0.01＝.结论 CRT术后无应答的发生率为28.57%.完全性右束支传导阻滞虽然也有QRS时限明显增宽,但CRT术后无应答的发生率明显增高.左心室电极导线的位置是决定CRT术后无应答发生的重要环节,心大静脉不宜做左心室电极导线置入的部位.     

心电图对心脏再同步化治疗是否应答的预测价值

目的探讨心电图在心脏再同步化治疗(CRT)应答中的预测价值。方法选取接受CRT(D)的患者作为研究对象,术后随访至少6个月,根据临床效果分为应答组与无应答组。分析术前术后患者QRS波时限,术前ST段下移值、QTc间期、有无病理性Q波及QRS波切迹对CRT应答是否有预测价值。结果共入选51例患者,6例失访,剩余45例纳入研究,24例CRT有应答,比例为53.3%,死亡8例。应答组术前心电图存在QRS波切迹明显低于无应答组(5/24 vs 16/21例,P=0.03);应答组术后心电图QRS波时限显著短于无应答组[(137.1±27.9)ms vs(166.3±28.5)ms,P0.05],且对CRT预后有预测价值(OR=0.964,95%CI 0.942~0.998,P=0.004),分界值为125 ms。结论心电图对CRT的应答有一定的预测作用。     

Mechanical Effects on Right Ventricular Function From Left Bundle Branch Block and Cardiac Resynchronization Therapy

ObjectivesThe purpose of this study was to investigate how LBBB and CRT modify RV free wall function by direct ventricular interaction.BackgroundRight ventricular (RV) function influences prognosis in patients with left bundle branch block (LBBB) and cardiac resynchronization therapy (CRT). There is, however, limited insight into how LBBB and CRT affect RV function.MethodsIn 24 patients with LBBB with nonischemic cardiomyopathy, RV and left ventricular (LV) strain by speckle-tracking echocardiography was measured before and after CRT. Underlying mechanisms were studied in 16 anesthetized dogs with ultrasonic dimension crystals and micromanometers.ResultsPatients with LBBB demonstrated distinct early systolic shortening in the RV free wall, which coincided with the typical abnormal early systolic septal shortening. In animals, this RV free wall contraction pattern resulted in reduced myocardial work as a large portion of the shortening occurred against low pressure during early systole, coinciding with abnormal leftward septal motion. RV systolic function was maintained by vigorous contraction in the late-activated LV lateral wall, which pushed the septum toward the RV. CRT reduced abnormal septal motion and increased RV free wall work because there was less inefficient shortening against low pressure.ConclusionsLBBB reduces workload on the RV free wall because of abnormal septal motion and delayed activation of the LV lateral wall. Restoring septal and LV function by CRT increases workload in RV free wall and may explain why patients with RV failure respond poorly to CRT. (Contractile Reserve in Dyssynchrony: A Novel Principle to Identify Candidates for Cardiac Resynchronization Therapy [CRID-CRT]; NCT02525185)     

Effect of cardiac surgery on ventricular septal motion: Assessment by intraoperative echocardiography and cross-sectional two-dimensional echocardiography

Echocardiographic evidence of paradoxical septal motion frequently occurs after cardiac surgery. To assess possible etiologic factors 17 patients were studied preoperatively, intraoperatively, and 7 days after surgery. Preoperative septal motion was normal in 14 and paradoxical in three (two with previous cardiac surgery, one with atrial septal defect [ASD]). Intraoperative septal motion prior to surgical procedure was normal in 16 and paradoxical in one (ASD). Septal motion (excursion and thickening fraction) was normal in all patients prior to chest closure. Echocardiograms of adequate quality were obtained at 7 days post surgery in 15 patients; septal motion was paradoxical in nine (group A) and normal in six (group B). No significant differences were seen between the two groups in ischemic time or in the preoperative to postoperative change in left ventricular (LV) and right ventricular diastolic dimension, shortening fraction, or septal and posterior wall thickening fraction. A significant postoperative decrease in septal excursion was seen in group A but not in group B; significant postoperative increases in posterior wall excursion were seen in both groups. Cross-sectional two-dimensional echocardiograms performed in 20 patients (8 normal, 12 postoperative paradoxical septal motion) were analyzed. In normal controls no significant change was detected in the LV centroid position during systole. In contrast, the 12 postoperative patients showed significant anterior displacement of the LV centroid and right septum during systole. Thus, paradoxical septal motion after cardiac surgery appears to relate to excessive anterior cardiac mobility due to pericardiotomy rather than to myocardial ischemia resulting from cardiopulmonary bypass.     

Regional patterns of dyssynchrony: lateral wall delay is desirable but not essential for left ventricular remodeling in biventricular pacing

Background: Tissue synchronization imaging (TSI), a parametric imaging technique based on tissue velocity imaging, often demonstrates patterns other than lateral delay in patients evaluated for cardiac resynchronization therapy (CRT). The prevalence of these patterns and their response to CRT has not been well described. We hypothesized that regional patterns of dyssynchrony might correlate with the extent of reverse remodeling. Methods: A consecutive series of 32 patients underwent echocardiographic study prior to CRT implant and 3 months postimplant. TSI was used to color‐code the time‐to‐peak positive systolic velocity at six basal and six mid‐LV segments. Each patient was assigned to one of four groups based on the predominant location of greatest delay (≥2 segments): (1) posterolateral delay, (2) septal delay, (3) no dyssynchrony, or (4) other. Results: Patients were classified as follows: posterolateral delay in 44% of patients (n = 14), septal delay in 28% (n = 9), no dyssynchrony in 16% (n = 5), and other pattern in 13% (n = 4). At 3‐month follow‐up, the group with the lateral delay pattern was associated with the greatest decrease in left ventricular end‐systolic volume (LVESV) and the largest improvement in left ventricular ejection fraction (LVEF) (?45 mL and +9.3%, respectively, P < 0.05). The LVESV in the other three groups changed as follows: ?24 mL (septal), ?28 mL (no dyssynchrony), and ?15 mL (other). Similar trends were observed for LVEF and left ventricular end‐diastolic volume. Conclusions: Despite the presence of wide QRS and a left bundle branch block, the most delayed segment is not always the posterolateral wall. Posterolateral delay is associated with the best response to CRT, while other patterns respond at a lower magnitude. (Echocardiography 2012;29:554‐559)     

Tissue Doppler derived mechanical dyssynchrony does not change after cardiac resynchronization therapy

Background: Mechanical left ventricular (LV) dyssynchrony, as determined by tissue Doppler imaging (TDI), predicts response to cardiac resynchronization therapy (CRT). However, changes in TDI mechanical dyssynchrony after CRT implantation have only limited investigation. Our objective was to detect changes in the extent and location of TDI mechanical dyssynchrony pre‐ and post‐CRT, and to explore their relationship in response to CRT. Methods: Thirty‐nine consecutive patients undergoing CRT implantation for chronic heart failure underwent TDI analysis pre‐CRT and up to 12 months post‐CRT. Regional dyssynchrony was determined by the time to systolic peak velocity of opposing LV walls. Dyssynchrony was defined as a difference in time to peak contraction of >105 msec. Two patients were excluded, as suitable coronary venous access was not available. Results: Of the 37 patients, 28 (76%) had significant mechanical dyssynchrony pre‐CRT. Of those with dyssynchrony, 18 (64%) had septal delay and 10 (36%) had LV free wall delay. Post‐CRT, 29 (78%) patients had significant mechanical dyssynchrony, 17 (59%) with septal delay, and 12 (41%) with LV free wall delay. There was no difference in both the amount of dyssynchrony (P = 0.8) or the location of the dyssynchrony (P = 0.5), before and after CRT, even though 28 (76%) were considered responders based on symptomatic and echocardiographic parameters. Conclusion: The TDI‐derived dyssynchrony does not change with CRT despite significant symptomatic and echocardiographic improvement in cardiac function. The TDI is of limited utility for monitoring response to CRT. (Echocardiography 2011;28:961‐967)     

慢性心力衰竭患者CRT治疗前后心功能与超敏C反应蛋白变化

目的观察慢性心力衰竭（CHF）患者行心脏再同步化治疗（CRT）前后心功能、超敏C反应蛋白（hs-CRP）变化及相互关系。方法对本院20例符合CRT置入指征的CHF患者行CRT,并于术后1个月、3个月、6个月行AV/VV优化,分别在术前、术后1个月、3个月、6个月采用胶乳凝集反应法测定hs-CRP水平,心脏彩超测定左室射血分数（LVEF）、左心室舒张末期内径（LVDd）、磁共振血管造影（MRA）、心脏超声测定室间隔及左室后壁收缩达峰时间延迟（SPWMD）等指标。结果 CRT治疗后患者的心脏功能明显好转,术后1个月、6个月心功能NYHA分级平均降低I级;LVEF、LVDd、MRA、SPWMD均逐渐好转（P〈0.05）,术后hs-CRP指标逐渐下降（P〈0.05）;NYHA分级与hs-CRP水平的下降具有相关性（r=0.78,P〈0.05）。结论 CHF患者行CRT治疗后,心功能可明显改善,hs-CRP与心功能存在负相关性。     

Serial echocardiographic profiles in infants and children with goarctation of the aorta

Eighty-three serial M mode echocardiograms were obtained from 13 medically managed infants and children aged 1 day to 3 1/2 years with coarctation documented at cardiac catheterization. Associated lesions included ventricular septal defect (two patients), atrial septal defect (two patients) and mild aortic stenosis (six patients). The echocardiograms were separated into four groups according to the patient's age: Group A, nine infants aged 1 day to 6 weeks; group B, nine infants aged 6 weeks to 4 months; group C, seven infants aged 4 months to 1 year; and group D, four children aged 1 to 3 1/2 years. Left ventricular diastolic dimension was significantly decreased in group A but gradually increased to normal with age. Right ventricular cavity dimension was significantly greater than normal in groups A and B and decreased toward normal with age. Right ventricular wall thickness was significantly increased initially and remained so. Septal and left ventricular posterior wall thickness measurements were not significantly different from normal in group A but increased progressively with age. Mean velocity of circumferential fiber shortening, corrected for heart rate, was significantly depressed in the youngest infants, despite digoxin therapy, but was normal thereafter. This study documents slight regression of right ventricular enlargement, left ventricular growth and hypertrophy and improvement in left ventricular function in growing infants and children with coarctation of the aorta. Echocardiography is useful in assessment of ventricular development in neonates with coarctation and in serial follow-up studies of cardiac adaptation to this lesion.     

Impact of left ventricular lead position in cardiac resynchronization therapy on left ventricular remodelling. A circumferential strain analysis based on 2D echocardiography.

Aims: To assess if myocardial deformation imaging allows definition of an optimal left ventricular (LV) lead position with improved effectiveness of cardiac resynchronization therapy (CRT) on LV reverse remodelling. METHODS: Circumferential strain imaging based on tracking of acoustic markers within 2D echo images (GE Ultrasound) was performed in 47 heart failure patients (59 +/- 9 years, 28 men) at baseline, one day postoperatively, 3 and 10 months after initiation of CRT. Myocardial deformation imaging was used to determine(1) the segment with latest peak negative systolic circumferential strain prior to CRT, and(2) the segment with maximal temporal difference of peak strain before-to-on CRT as the segment with greatest benefit of CRT and assumed LV lead position. Anatomic LV lead position was determined by fluoroscopy. Optimal LV lead position was defined as concordance or immediate neighbouring of the segment with latest systolic strain prior to CRT and segment with assumed LV lead position. RESULTS: Agreement of assumed LV lead position based on strain analysis and LV lead position defined by fluoroscopy were high (kappa = 0.847). At 10 month follow-up, there was greater increase of EF (12 +/- 3 vs. 7 +/- 4%, P < 0.001), greater decrease of left ventricular end-diastolic volume (LVEDV) (23 +/- 8 vs. 13 +/- 7 mL, P < 0.001) and left ventricular end-systolic volume (LVESV) (42 +/- 10 vs. 27 +/- 8 mL, P < 0.001), and greater increase of VO(2)max (2.8 +/- 0.8 vs. 1.9 +/- 1.0 mL/kg/min, P = 0.035) in the optimal (n = 28 patients) compared to the non-optimal LV lead position group (n = 19 patients). The distance between segment with latest systolic strain prior to CRT and segment with assumed LV lead position was the only independent predictor of DeltaLVEDV and DeltaLVESV at 10 month follow-up (R(2) = 0.2175, P = 0.0197) and (R(2) = 0.3774, P = 0.0054), respectively. CONCLUSION: Detailed analysis of the myocardial contraction sequence using circumferential strain imaging allows determination of the LV lead position in CRT. Optimal LV lead position in CRT defined by circumferential strain analysis results in greater improvement in LV function and more LV reverse remodelling than non-optimal LV lead position.     

Right bundle branch block and impaired left ventricular function as evidence of a left ventricular conduction delay.

BACKGROUND: The indications and efficacy of cardiac resynchronization therapy (CRT) have not been sufficiently clarified in patients with right bundle branch block (RBBB). METHODS AND RESULTS: This study included 55 patients with normal QRS morphology and duration (Control-Gr) and 49 patients with complete RBBB (CRBBB-Gr). Using tissue Doppler imaging, the time difference (TD) between the electromechanical delay of the septal wall, left ventricular (LV) lateral wall, and right ventricular free wall were measured. Using tissue tracking imaging, the coefficient of the time variation from the beginning of the QRS to the peak displacement time of 6 regions of the LV (CV-PMDLV) was calculated. The TD between the septal wall and that of the LV lateral wall (TDSEPT-LAT) did not differ between the Control-Gr and RBBB-Gr. However, a significant difference was found in the TDSEPT-LAT between the CRBBB patients with LV systolic dysfunction (ejection fraction (EF) < or =50%) and those with normal LV function (EF >50%; p<0.001). The CV-PMDLV was greater in the CRBBB patients with LV systolic dysfunction than in those with a normal LV function (p<0.05). The RBBB-Gr patients with LV dysfunction and a great TDSEPT-LAT, improved clinically after the CRT. CONCLUSIONS: The presence of RBBB and LV dysfunction may indicate LV dyssynchrony and a heterogeneous mechanical dysfunction.     

Effect of cardiac resynchronization therapy in isolated ventricular noncompaction in adults: follow-up of four cases

Background: An isolated ventricular noncompaction (IVNC) is an unclassified cardiomyopathy and, despite the increasing awareness of and interest in this disorder, the role of cardiac resynchronization therapy (CRT) remains obscure. Objective: The purpose of this study was to clarify the long‐term effect of CRT on IVNC in adult patients. Methods: Four cases of IVNC were included in this study. Before the CRT device was implanted, all four patients (54 ± 16‐year‐old, 4 males) presented with symptomatic congestive heart failure. Echocardiography revealed their systolic dysfunction and their left ventricular ejection fraction (LVEF) was 21 ± 8%. There was also mechanical dyssynchrony observed between the LV septum and free wall area. The QRS duration was “narrow” (112 and 120 ms) in two patients. One patient had been resuscitated from ventricular fibrillation (VF) and two had nonsustained ventricular tachycardia (VT). A CRT defibrillator (CRT‐D) was implanted in three patients with VT/VF and a CRT pacemaker (CRT‐P) in a patient without VT/VF. The LV lead was positioned in a lateral branch of the coronary sinus where a thickened noncompacted wall existed. Results: During the follow‐up period (28 ± 23 months), their congestive heart failure had improved in terms of the cardiothoracic ratio on the chest X‐ray, B‐type natriuretic peptide level, LV systolic dimension, and LVEF. No episodes of defibrillation shocks were observed. Conclusion: CRT may improve the prognosis and quality‐of‐life in patients with an IVNC with mechanical dyssynchrony.