心脏再同步治疗中膈神经刺激的单中心回顾分析

Objective To analyze the phrenic nerve stimulation and the appropriate treatment during and after CRT/CRT-D implantation. Methods Seventy-nine patients (45 men and 34 women, aged 35 ～ 86 years) received CRT/CRT-D implantation. The patients were followed up for average 24 months. The phrenic nerve stimulations was analyzed and the corresponding treatments were taken. Results Seventy-eight patients received successful implantation(98. 7% ). The incidence rates of the phrenic nerve stimulation is 12. 8% during and after the implantation. Posterior veins and posterior lateral veins are predilection sites. The risk increased in the patients with short stature and enlarged heart. Phrenic nerve stumilation can be eliminated by adjusting the electrode position, output voltage pulse, width and changing the polarity. Nobody needs another operation because of the phrenic nerve stimulation. Conclusions Phrenic nerve stimulation is a common complication of CRT/CRT-D implantation operation. Doctors should take great attention to prevent this complication during the implanting procedure and follow-up.     

心脏再同步治疗中膈神经刺激的单中心回顾分析

目的 探讨心脏再同步治疗(CRT)植入术中、术后膈神经刺激发生情况及处理方法.方法 心力衰竭患者79例,其中男性45例,女性34例,年龄35～86岁,接受CRT/CRT-D植入术.术后平均随访24个月,观察膈神经刺激发生情况,同时给予相应的处理措施.结果 78例患者成功植入,成功率为98.7%.植入术中、术后膈神经刺激发生率为12.8%.后静脉、侧后静脉是其好发部位,身材偏矮小及心脏增大的患者CRT植入中出现膈神经刺激危险性增高.调整电极导线位置、输出电压和脉宽以及改变极性等方法,可以有效消除膈神经刺激.结论 膈神经刺激是CRT/CRT-D植入术中、术后的常见并发症;严格做好术中预防、术后随访,及时采取有效的干预手段,以减少或避免膈神经刺激的发生.     

心脏再同步治疗中膈神经刺激的单中心回顾分析

Objective To analyze the phrenic nerve stimulation and the appropriate treatment during and after CRT/CRT-D implantation. Methods Seventy-nine patients (45 men and 34 women, aged 35 ～ 86 years) received CRT/CRT-D implantation. The patients were followed up for average 24 months. The phrenic nerve stimulations was analyzed and the corresponding treatments were taken. Results Seventy-eight patients received successful implantation(98. 7% ). The incidence rates of the phrenic nerve stimulation is 12. 8% during and after the implantation. Posterior veins and posterior lateral veins are predilection sites. The risk increased in the patients with short stature and enlarged heart. Phrenic nerve stumilation can be eliminated by adjusting the electrode position, output voltage pulse, width and changing the polarity. Nobody needs another operation because of the phrenic nerve stimulation. Conclusions Phrenic nerve stimulation is a common complication of CRT/CRT-D implantation operation. Doctors should take great attention to prevent this complication during the implanting procedure and follow-up.     

行心脏再同步化治疗的患者发生膈神经刺激的预测因素

目的探讨心脏再同步治疗(CRT)植入术后膈神经刺激的发生情况及其预测因素。方法入选接受CRT植入术者,术后随访观察膈神经刺激发生情况,根据有无膈肌症状分为有症状组和无症状组。有症状组给予相应的处理措施。分析膈神经刺激的预测因素。结果共入选31例,其中10例(32%)术后发生了膈神经刺激,8例通过程控可缓解症状。左室电极植入在后侧静脉发生膈神经刺激的风险高(P=0.047)。单极与双极电极膈神经刺激的发生无差异(P=0.677)。多因素分析显示左室电极植入在后侧静脉(P=0.047)、膈神经刺激试验阳性(P=0.003)、术前QRS波时限较窄(P=0.003)和6个月后左室起搏阈值升高(P=0.031)可预测术后是否发生膈神经刺激症状。结论左室电极植入在后侧静脉、膈神经刺激试验阳性、术前QRS波时限较窄和6个月后左室起搏阈值升高是CRT患者术后发生膈神经刺激的预测因素。     

Phrenic nerve stimulation in cardiac resynchronization therapy

In cardiac resynchronization therapy (CRT), the electrical impulse delivered by the left ventricular (LV) lead may incidentally cause phrenic nerve stimulation (PNS). The purpose of this state-of-the-art review is to describe the frequency, risk factors, and clinical consequences of PNS and to present the most recent options to successfully manage PNS. PNS occurs in 2 to 37 % of implanted patients and is not always detected in the supine position during implantation. Lateral and posterior veins are at higher risk of PNS than anterior veins, and apical positions are at higher risk of PNS than basal positions. The management of PNS discovered during implantation may include mapping the course of the target vein in order to find a PNS-free site, targeting another vein if available, and pacing with alternative configurations before changing the lead location. Non-invasive options for management of post-operative PNS depend on the difference between PNS and LV stimulation thresholds and include reducing the LV pacing output, automatic determination of LV stimulation threshold and minimal output delivery by the device, increasing the pulse duration, and electronic repositioning. New quadripolar leads allow to pace from different cathodes, and the multiple pacing configurations available have proved superior to bipolar leads in mitigating PNS. This electronic repositioning addresses almost all of the clinically relevant PNS and should markedly reduce the need for invasive lead repositioning or CRT abandon, which is actually the last option for 2 % of patients.     

Isolation of the phrenic nerve to suppress diaphragmatic contraction induced by cardiac resynchronization

Left phrenic nerve stimulation is a well-known complication of cardiac resynchronization therapy (CRT). We report a case where electronic or anatomical repositioning of the left ventricular (LV) electrode (within the coronary sinus tributaries) was not feasible/effective. Surgical graft interpositioning was performed to successfully isolate the phrenic nerve from the previously implanted coronary sinus epicardial LV lead.     

Optimizing cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) improves clinical outcome and survival in advanced heart failure. However, some patients do not respond clinically or show improvement in left ventricular function. Our focus has turned to why such “nonresponders” exist. Follow-up of CRT has led to several explanations, varying by individual patient, and has shown the importance of device programming in CRT in heart failure. The failing heart displays delayed contraction in the ventricle, also referred to as mechanical dyssynchrony. Simply pacing both ventricles simultaneously might not be adequate to optimize systolic function. Individually tailoring the atrioventricular (AV) timing can improve left ventricular filling and cardiac output, and adjusting the interventricular (VV) pacing delay has also been shown to improve hemodynamics. Increasing evidence regarding AV and VV optimization is emerging. This article reviews the current data on optimization, including the physiology, numerous approaches, and current issues.     

心脏再同步治疗超反应的预测因素研究

目的 寻找心脏再同步治疗（CRT）超反应可能的预测因素.方法 将66例植入CRT的患者分为超反应组和非超反应组,通过组间比较、Logistic回归分析以及绘制受试者工作（ROC）曲线等方法寻找CRT超反应的独立预测因子,并评价其预测价值.结果 超反应患者中男性、右束支阻滞少,左束支阻滞多,植入术前左心室舒张末内径（LVEDD）小,术后QRS时限短,但只有术前LVEDD是CRT超反应的独立预测因子,术前LVEDD≤68.5 mm预测CRT超反应的敏感性为84.6%,特异性为76.9%.结论 植入术前左心室较小的CRT治疗患者更容易从这一器械治疗中获益.     

心脏再同步治疗超反应的预测因子分析

目的 心脏再同步治疗（CRT）能明显改善患者临床症状,逆转心肌重构,称之为CRT超反应.本文主要分析CRT术后,患者超反应的预测因子.方法 采用回顾性研究,2005年1月至2010年6月共有124例随访资料完整的CRT或心脏再同步治疗除颤器（CRT-D）纳入分析,分为超反应组及其他反应组.并在CRT术后第6个月随访时,进行临床评估及超声心动图评价.心功能（NYHA分级）提高≥1级,左心室射血分数（LVEF） ≥0.45或增加2倍以上称为超反应.结果 两组患者在基线状态除QRS时限[（160.2±36.1）ms对（139.6±32.5）ms,P=0.01],完全左束支阻滞比例（95％对82％,P=0.02）、心力衰竭症状出现时间[（21.0±14.6）个月对（36.0±25.3）个月,P=0.02]差异有统计学意义外,其余参数在基线状态差异无统计学意义;有17％的患者出现超反应.6个月随访时超反应组与其他反应组在心功能分级、脑钠肽（BNP）、QRS时限、LVEF及因心力衰竭住院率方面有明显改善.结论 完全左柬支阻滞及心力衰竭症状出现较短的患者CRT反应较好.     

冠状动脉介入治疗联合心脏再同步化治疗缺血性心肌病顽固性心力衰竭

目的　观察经皮冠状动脉介入治疗 (PCI)联合心脏再同步化治疗 (CRT)缺血性心肌病顽固性心力衰竭的疗效和安全性。方法　 7例均经冠状动脉造影证实为缺血性心肌病 ,NYHA分级Ⅳ级 ;其中 6例伴有心室内传导阻滞且QRS时限≥ 130ms,1例三度房室传导阻滞 ,1例持续性快速心房颤动 ,2例曾发作心室颤动 ,左室舒张末期内径≥ 5 5mm ,左室射血分数≤ 0 4 0。 5例PCI术后 6个月复查冠状动脉造影均无再狭窄 ,其后行CRT ;2例先行CRT 2周后行PCI。结果　PCI和CRT手术均成功 ,5例为右房加双室三腔起搏 ,1例快速心房颤动者行CRT同时行房室结射频消融术 ,1例行心脏三腔起搏除颤器置入术。 1例术后 4个月死于再次急性心肌梗死 ,其余 6例存活者随访 5～4 1(2 3 2± 13 8)个月 ,5例先行PCI及 2例先行CRT者联合介入治疗后心功能进一步明显改善 ,NYHA提高 2级 ,6min步行距离明显增加 ,超声二尖瓣反流和心电图QRS时限明显减少。 2例无室壁瘤者左室舒张末期内径及左室射血分数明显改善 ,5例轻度改善或无明显变化。结论　PCI及CRT联合治疗缺血性心肌病顽固性心力衰竭可改善心功能 ,提高生活质量并改善其预后 ,并具有较高的安全性。     

The problem of non-response to cardiac resynchronization therapy

PURPOSE OF REVIEW: Cardiac resynchronization therapy improves quality of life, exercise performance, left ventricular ejection fraction, and reduces heart failure hospitalizations and mortality in patients with New York Heart Association class III or IV congestive heart failure and intraventricular conduction delay. A number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to cardiac resynchronization therapy. These issues are also relevant to patients who do respond to cardiac resynchronization therapy as potentially their response might be further increased. This article will review the data regarding the frequency of the problem of non-response to cardiac resynchronization therapy and then discuss the postulated reasons and potential solutions. RECENT FINDINGS: Rates of non-response to cardiac resynchronization therapy are often quoted as 20-30%, but a critical analysis of the data would suggest the true non-responder rate can be estimated as perhaps 40-50%. The data indicate that on a population basis non-response is multi-factorial and the extent of mechanical dyssynchrony, left ventricular pacing site and cause of congestive heart failure are likely to be important. Ongoing research is exploring the utility of various techniques for quantifying mechanical dyssynchrony and the potential benefits of targeted left ventricular lead placement and post-implant optimization. SUMMARY: Cardiac resynchronization therapy is a major breakthrough in treatment for advanced congestive heart failure patients. There is substantial rate of non-response to this therapy, however, and research is exploring various ways to increase the response to the technique.     

Optimization of cardiac resynchronization therapy

Cardiac resynchronization is now an accepted and widespread therapy for patients with left ventricular (LV) systolic dysfunction. However, there are still a significant number of patients that do not appear to gain benefit, and this is currently the focus of a great deal of research. Contemporary resynchronization devices allow manipulation of both atrioventricular (AV) and ventricular-to-ventricular (VV) delays and there is evidence that optimization of these delays has a positive effect on hemodynamics. However, there are many ways that optimization can be performed and there is little consensus on how, if at all, it should be incorporated into clinical practice.     

How to predict response to cardiac resynchronization therapy?

Cardiac resynchronization therapy (CRT) is considered a majorbreakthrough in the treatment of patients with end-stage heartfailure.¹ Initial studies demonstrated an acute improvementin haemodynamics immediately after CRT, whereas a large numberof studies with mid-term follow-up (6 months to 1 year) demonstratedan improvement in heart failure symptoms, quality-of-life score,exercise capacity, and left ventricular (LV) systolic performance.¹In addition, Bradley et al.² demonstrated in a meta-analysis,a reduced risk for heart failure death at mid-term (6 months)follow-up in patients undergoing CRT when compared with optimizedmedical therapy. Moreover, studies with long-term follow-upnow demonstrate sustained improvement over     

慢性心力衰竭心脏再同步治疗超级反应患者的临床特征

目的接受心脏再同步治疗（CRT）的慢性心力衰竭患者中,部分患者心脏结构和功能显著改善,甚至可以恢复至接近正常,即所谓的超级反应患者（super－responders,SR）,本文回顾分析这些超级反应患者的临床特征,寻找有价值的CRT超级反应患者的预测指标。方法2005年6月至2010年1月在本中心因慢性心力衰竭植入CRT·P／CRT—D的患者共69例,其中有较完整随访资料的50例纳入本研究。CRT超级反应患者判断标准为左心室射血分数（LVEF）绝对值增加≥0．20。回顾性分析50例患者中超级反应患者和非超级反应患者的临床特征,比较两组患者之间的差异。结果平均随访时间（13．9±11．5）个月,达到超级反应标准患者11例（22％）,与术前相比LVEF显著升高（0．58±0．05对0．33±0．05,P〈0．001）。超级反应组和非超级反应组术前资料除性别（女性比例：8／11对11／39,P=0．013）、QRS时限[（163．2±19．3）ms对（140．2±29．1）ms,P=0．018]、左束支阻滞的比例（10／11对20／39,P＝0．04）外差异无统计学意义。多元logistic回归分析显示女性合并完全性左束支阻滞是CRT超级反应的惟一独立预测因子。结论CRT中超级反应患者以女性、QRS时限增宽以及合并左束支阻滞患者多见。女性合并左束支阻滞是CRT超级反应的独立预测因子。     

心脏再同步治疗无反应患者的术前预测因素

新世纪以来,一系列大型临床研究证实了心脏再同步治疗（CRT）不但能改善心力衰竭患者的心功能,提高其生活质量,还能降低其死亡率[1]。CRT已成为心力衰竭治疗的有效手段。在目前国内外的指南中,CRT治疗IA类适应证为：左心室射血分数（LVEF）≤0．35、心功能Ⅲ～Ⅳ级（NYHA分级）、QRS时限≥120111S、窦性心律、充分的药物治疗无效的心力衰竭患者？然而,即使按指南的建议选择病人仍有约30％患者对CRT治疗尤反应。由于CRT治疗费用昂贵,     

Sympathetic nerve activity after thoracoscopic cardiac resynchronization therapy in congestive heart failure

BACKGROUND: Sympathetic benefits of thoracoscopic cardiac resynchronization therapy (TCRT) in congestive heart failure (CHF) are unknown. We determined cardiac hemodynamics, functional status, and muscle sympathetic nerve activity (MSNA) in a group of TCRT patients. We aimed to compare these patients with CHF patients with cardiac asynchrony (ASY) to substantiate the beneficial effects of TCRT. METHODS AND RESULTS: Eleven patients resynchronized by TCRT 6 +/- 1 months before study inclusion (SYN) and 10 matched ASY patients underwent blood pressure, heart rate, and MSNA recordings. All underwent functional status, cardiac index, and left ventricular ejection fraction (LVEF) assessments. SYN patients had shorter QRS duration and interventricular mechanical delays, longer 6 minute walking distance and lower New York Heart Association class (all P < .05) than ASY patients. MSNA of 56 +/- 2 bursts/min in ASY patients was higher than in SYN patients (48 +/- 3 bursts/min, P < .05). Cardiac index was higher in SYN patients than in ASY patients (2.8 +/- 0.2 versus 1.9 +/- 0.2 L.min.m2, P < .05, respectively). MSNA was highest in the patients with the lowest LVEF (r = -0.49, P < .05), cardiac index (r = -0.48, P < .05) and 6-minute walking distance (r = -0.50, P < .05). CONCLUSION: Lower sympathetic nerve activities in TCRT patients are related to more favorable cardiac indexes and six minute walking distances suggesting a sympathetic, hemodynamic, and functional improvement by TCRT.