Six months clinical outcome comparison between quadripolar and bipolar left ventricular leads in cardiac resynchronization therapy: A prospective,non-randomized,single-centre observational study

Background and objectivesQuadripolar left ventricular (LV) leads in cardiac resynchronization therapy (CRT) offer multi-vector pacing with different pacing configurations and hence enabling LV pacing at most suitable site with better lead stability. We aim to compare the outcomes between quadripolar and bipolar LV lead in patients receiving CRT.MethodsIn this prospective, non-randomized, single-center observational study, we enrolled 93 patients receiving CRT with bipolar (BiP) (n = 31) and quadripolar (Quad) (n = 62) LV lead between August 2016 to August 2019. Patients were followed for six months, and outcomes were compared with respect to CRT response (defined as ≥5% absolute increase in left ventricle ejection fraction), electrocardiographic, echocardiographic parameters, NYHA functional class improvement, and incidence of LV lead-related complication.ResultsAt the end of six months follow up, CRT with quadripolar lead was associated with better response rate as compared to bipolar pacing (85.48% vs 64.51%; p = 0.03), lesser heart failure (HF) hospitalization events (1.5 vs 2; p = 0.04) and better improvement in HF symptoms (patients with ≥1 NYHA improvement 87.09% vs 67.74%; p = 0.04). There were fewer deaths per 100 patient-year (6.45 vs 9.37; p = 0.04) and more narrowing of QRS duration (Δ12.56 ± 3.11 ms vs Δ7.29 ± 1.87 ms; p = 0.04) with quadripolar lead use. Lead related complications were significantly more with the use of bipolar lead (74.19% vs 41.94%; p = 0.02).ConclusionsOur prospective, non-randomized, single-center observational study reveals that patients receiving CRT with quadripolar leads have a better response to therapy, lesser heart failure hospitalizations, lower all-cause mortality, and fewer lead-related complications, proving its superiority over the bipolar lead.     

Anodal stimulation: an underrecognized cause of nonresponders to cardiac resynchronization therapy

Objective

The purpose of this study was to determine if anodal stimulation accounts for failure to benefit from cardiac resynchronization therapy (CRT) in some patients.

Background

Approximately 30-40% of patients with moderate to severe heart failure do not have symptomatic nor echocardiographic improvement in cardiac function following CRT. Modern CRT devices allow the option of programming left ventricular (LV) lead pacing as LV tip to right ventricular (RV) lead coil to potentially improve pacing thresholds. However, anodal stimulation can result in unintentional RV pacing (anode) instead of LV pacing (cathode).

Methods

Patients enrolled in our center''s CRT registry had an echocardiogram, 6-minute walk (6MW), and Minnesota Living with HF Questionnaire (MLHFQ) pre-implant and 6 months after CRT. Electrocardiograms (12 lead) during RV, LV, and biventricular (BiV) pacing were obtained at the end of the implant in 102 patients. Anodal stimulation was defined as LV pacing QRS morphology on EKG being identical to RV pacing or consistent with fusion with RV and LV electrode capture. LV end systolic volume (LVESV) was measured by echo biplane Simpson''s method and CRT responder was defined as 15% or greater reduction in LVESV.

Results

Of the 102 patients, 46 (45.1%) had the final LV lead pacing configuration programmed LV (tip or ring) to RV (coil or ring). 3 of the 46 subjects (6.5%) had EKG findings consistent with anodal stimulation, not corrected intraoperatively. All anodal stimulation patients were nonresponders to CRT by echo criteria (reduction in LVESV 13.3 ± 0.6%, increase in EF 5.0 ± 1.4%) compared to 46% responders for those without anodal stimulation, (change in LVESV 18.7 ± 25.6%, EF 7.6 ±10.9%). None of the anodal stimulation patients were responders for the 6 minute walk, compared to 32 of 66 (48%) of those without anodal stimulation.

Conclusion

Anodal stimulation is a potential underrecognized and ameliorable cause of poor response to CRT.     

短暂中断慢性心力衰竭患者心脏再同步化治疗后心脏运动同步性变化的临床研究

目的：观察短暂中断心脏再同步化治疗（CRT）后慢性心力衰竭患者（CHF）心脏运动同步性的变化,探讨CRT逆重构组与非逆重构组同步性的获益情况。方法：连续选择CRT术后6月以上的患者46例,根据左室收缩末容积减小≥15%分为逆重构组和非逆重构组。分别于起搏器关闭前及关闭后10分钟超声心动图检查房室间延迟（AVD）、心室间延迟（IVD）、2节段径向应变达峰时间标准差（PTrs-12SD）、12节段环向应变达峰时间标准差（PTcs-12SD）及16节段纵向应变达峰时间标准差（PTls-16SD）,比较起搏器关闭前后上述参数的变化。结果：两组患者中断CRT 10分钟后AVD均减小（非逆重构组P〈0.05,逆重构组P〈0.01）,逆重构组IVD减小（P〈0.01）,非逆重构组IVD于CRT关闭后变化无统计学意义（P〉0.05）;两组患者左室内同步化参数PTcs-12SD、PTrs-12SD、PTls-16SD在中断CRT 10分钟后的变化均无统计学意义（P〉0.05）。结论：中断CRT10分钟后,两组患者房室失同步均加重,仅逆重构组心室间失同步显著恶化。提示CRT期间,两组患者均可持续获得房室同步性益处,逆重构患者可获得心室间同步性益处;中断CRT10分钟后,两组左心室内同步性均未发生显著性改变,这种无差异的现象,需要进一步研究。     

慢性心力衰竭患者心脏再同步化治疗的疗效及其影响因素分析

目的:观察慢性心衰患者经心脏再同步化治疗(cardiac resynchronization therapy,CRT)的临床疗效,并分析CRT无应答的影响因素。方法:入选2010年1月至2015年7月上海长海医院心血管内科因心衰接受CRT的患者共47例,收集病史资料、手术资料、术后资料以及随访,比较CRT有无应答患者的临床特征,并通过多因素回归分析CRT无应答的危险因素。结果:纳入病例数共47例,其中CRT应答34例(72.3%),CRT无应答13例(27.7%)。CRT无应答组中心房颤动和冠脉问题发生率明显高于CRT应答组(P0.05);CRT应答组中左心房容积、右心房容积、左心室容积以及二尖瓣返流量均明显低于CRT无应答组(P0.05)。多因素回归分析显示患者合并心房颤动或冠脉问题是CRT无应答可以影响CRT的应答。结论:CRT对慢性心衰患者具有较好的疗效,而合并心房颤动或冠脉问题是预测慢性心衰患者CRT无应答的独立影响因素。     

The Benefit of Atrioventricular Junction Ablation for Permanent Atrial Fibrillation and Heart Failure Patients Receiving Cardiac Resynchronization Therapy: An Updated Systematic Review and Meta-analysis

BackgroundAtrial fibrillation (AF) is correlated with a poor biventricular pacing and inadequate response to cardiac resynchronization therapy (CRT). Biventricular pacing improvement can be achieved by conducting the atrioventricular junction ablation (AVJA). We aimed to investigate the benefit of AVJA for permanent AF and heart failure with reduced ejection fraction (HFrEF) patients receiving CRT.MethodsIn August 2020, a systematic review and meta-analysis study comparing CRT plus AVJA versus CRT for permanent AF and HFrEF patients was conducted. Relevant articles were identified through the electronic scientific database such as ClinicalTrials.gov, ProQuest, ScienceDirect, PubMed, and Cochrane. The pooled risk ratio (RR) and pooled mean difference (MD) were estimated.ResultsA total of 3199 patients from 14 cohort studies were involved in this study. Additional AVJA reduced cardiovascular mortality (RR = 0.75, 95% confidence interval [CI] = 0.61 to 0.93, P < 0.01) in permanent AF and HFrEF patients receiving CRT. Biventricular pacing rate was higher in CRT plus AVJA group (MD = 8.65%, 95% CI = 5.62 to 11.67, P < 0.01) than in CRT alone group. The reverse remodeling characterized by the reduction of left ventricular end-diastolic diameter (LVEDD) was greater in the CRT plus AVJA group (MD = ?2.11 mm, 95% CI = ?3.79 to ?0.42, P = 0.01).ConclusionIn permanent AF and HFrEF patients receiving CRT, AVJA effectively increased the biventricular pacing rate. Adequate biventricular pacing rate provided a better response to the CRT marked by the greater ventricular reverse remodeling and survival from cardiovascular mortality.     

New insights in LV torsion for the selection of cardiac resynchronisation therapy candidates

Recent literature indicates that torsion of the left ventricle (LV) is a promising predictor for response to cardiac resynchronisation therapy (CRT). Among patients with severe heart failure, 45 to 75% of patients show rigid body rotation, where the base and apex rotate in the same direction, instead of normal, opposite rotation. The occurrence of this phenomenon seems to be a good indicator for response to CRT. From this review, it can be concluded that LV torsion might be a welcome addition to current selection criteria.     

Chronic cardiac resynchronization therapy and reverse ventricular remodeling in a model of nonischemic cardiomyopathy

While cardiac resynchronization therapy (CRT) has been shown to reduce morbidity and mortality in heart failure (HF) patients, the fundamental mechanisms for the efficacy of CRT are poorly understood. The lack of understanding of these basic mechanisms represents a significant barrier to our understanding of the pathogenesis of HF and potential recovery mechanisms. Our purpose was to determine cellular mechanisms for the observed improvement in chronic HF after CRT. We used a canine model of chronic nonischemic cardiomyopathy. After 15 months, dogs were randomized to continued RV tachypacing (untreated HF) or CRT for an additional 9 months. Six minute walk tests, echocardiograms, and electrocardiograms were done to assess the functional response to therapy. Left ventricular (LV) midmyocardial myocytes were isolated to study electrophysiology and intracellular calcium regulation. Compared to untreated HF, CRT improved HF-induced increases in LV volumes, diameters and mass (p<0.05). CRT reversed HF-induced prolongations in LV myocyte repolarization (p<0.05) and normalized HF-induced depolarization (p<0.03) of the resting membrane potential. CRT improved HF-induced reductions in calcium (p<0.05). CRT did not attenuate the HF-induced increases in LV interstitial fibrosis. Using a translational approach in a chronic HF model, CRT significantly improved LV structure; this was accompanied by improved LV myocyte electrophysiology and calcium regulation. The beneficial effects of CRT may be attributable, in part, to improved LV myocyte function.     

Atrial electrogram quality in single-pass defibrillator leads with floating atrial bipole in patients with permanent atrial fibrillation and cardiac resynchronization therapy

Many patients receiving cardiac resynchronization therapy (CRT) suffer from permanent atrial fibrillation (AF). Knowledge of the atrial rhythm is important to direct pharmacological or interventional treatment as well as maintaining AV-synchronous biventricular pacing if sinus rhythm can be restored. A single pass single-coil defibrillator lead with a floating atrial bipole has been shown to obtain reliable information about the atrial rhythm but has never been employed in a CRT-system. The purpose of this study was to assess the feasibility of implanting a single coil right ventricular ICD lead with a floating atrial bipole and the signal quality of atrial electrograms (AEGM) in CRT-defibrillator recipients with permanent AF.

血清Cys-C、TBiL、MR-proADM、AGEs与老年慢性心力衰竭患者心功能和心脏再同步化治疗应答的关系研究

摘要 目的：探讨血清胱抑素C（Cys-C）、总胆红素（TBiL）、肾上腺髓质中段肽（MR-proADM）、晚期糖基化终末产物（AGEs）与老年慢性心力衰竭（CHF）患者心功能和心脏再同步化治疗（CRT）应答的关系。方法：选择2020年3月至2022年1月我院收治的151例接受CRT治疗的老年CHF患者为研究对象,随访6个月,统计治疗应答情况。CRT治疗前检测血清Cys-C、TBiL、MR-proADM、AGEs水平,超声心动图检测心功能,分析血清Cys-C、TBiL、MR-proADM、AGEs与心功能的相关性以及与老年CHF患者CRT治疗应答的关系。结果：151例患者失访1例,余150例患者中无应答48例（无应答组）,应答102例（应答组）。无应答组血清Cys-C、TBiL、MR-proADM、AGEs水平均高于应答组（P＜0.05）,且与左心室射血分数（LVEF）呈负相关（P＜0.05）,与左室舒张末期内径（LVEDD）和左室收缩末期内径（LVESD）呈正相关（P＜0.05）。多因素Logistic回归分析结果显示缺血性心肌病、血清Cys-C、TBiL、MR-proADM、AGEs是老年CHF患者CRT治疗无应答的危险因素（P＜0.05）,LVEF是保护因素（P＜0.05）。结论：CRT治疗无应答老年CHF患者血清Cys-C、TBiL、MR-proADM、AGEs水平升高,且与心功能下降有关。血清Cys-C、TBiL、MR-proADM、AGEs是CRT治疗无应答的危险因素,可为CRT治疗效果评估提供一定的参考。     

血清Apelin、CD40L、Gal-3与慢性心力衰竭患者心脏再同步化治疗后室性心律失常的关系及其预测价值研究

摘要 目的：探讨血清爱帕琳肽（Apelin）、分化簇40配体（CD40L）、半乳糖凝集素-3（Gal-3）与慢性心力衰竭（CHF）患者心脏再同步化治疗（CRT）后室性心律失常的关系及其预测价值。方法：选取2018年1月～2022年10月在山西医科大学附属太钢总医院、山西医科大学附属心血管病医院接受CRT的CHF患者共235例纳入CHF组,另选取同期上述两院共150名体检健康者作为对照组。检测并对比所有受试者的血清Apelin、CD40L、Gal-3水平。CHF患者CRT后随访1年,根据是否发生室性心律失常分为室性心律失常组（48例）和非室性心律失常组（187例）。多因素Logistic回归分析CHF患者CRT后室性心律失常发生的影响因素。受试者工作特征（ROC）曲线分析血清Apelin、CD40L、Gal-3预测CHF患者CRT后室性心律失常发生的价值。结果：与对照组比较,CHF组血清Apelin水平降低,CD40L、Gal-3水平升高（P＜0.05）。随访1年,235例CHF患者CRT后室性心律失常发生率为20.43%。Apelin升高为CHF患者CRT后室性心律失常发生的保护因素,纽约心脏病协会（NYHA）心功能分级Ⅳ级和CD40L、Gal-3升高为危险因素（P＜0.05）。联合血清Apelin、CD40L、Gal-3预测CHF患者CRT后室性心律失常发生的曲线下面积（AUC）为0.911,大于血清Apelin、CD40L、Gal-3单独预测的0.770、0.754、0.760。结论：CHF患者的血清Apelin水平降低、CD40L、Gal-3水平升高与CRT后室性心律失常的发生有关,血清Apelin、CD40L、Gal-3水平联合检测对CHF患者CRT后室性心律失常的发生具有较高的预测价值。     

Influence of intrinsic myocardial conduction on paced QRS morphology during cardiac resynchronization therapy follow up

We report two cases of patients of cardiac resynchronization therapy (CRT) whose ECGs, during follow up, showed different paced QRS morphology as compared to those of immediate post-device implantation. Parameters of leads, including sensitivity and capture thresholds, were unchanged. There was no lead dislodgement confirmed on fluoroscopy. The ECGs obtained in device off mode showed different intrinsic QRS morphology as compared to those of pre-implant morphology. These changes were attributable to electrolyte imbalance in one patient and progressive intraventricular conduction defect in the other. These cases demonstrate that intrinsic myocardial conduction pattern influences paced QRS morphology. Irreversible change in paced QRS morphology may indicate poor prognosis.     

Utility of the NavX® Electroanatomic Mapping System for Permanent Pacemaker Implantation in a Pregnant Patient with Chagas Disease

Chagas disease is a highly prevalent zoonosis in Mexico, Central, and South America. Early cardiac involvement is one of the most serious complications of this disease, and conduction disturbances may occur at an early age. We describe a young pregnant woman with Chagas disease and a high degree atrioventricular block, who required implantation of a permanent dual chamber pacemaker. Using an electroanatomic navigation EnSite NavX® system the pacemaker was successfully implanted with minimal fluoroscopic exposure. This case demonstrates the safety and feasibility of using an electroanatomic navigation system to guide permanent pacemaker implantation minimizing x-ray exposure in pregnant patients.     

Optimisation of cardiac resynchronization therapy in clinical practice during exercise

Aims

Although cardiac resynchronisation therapy (CRT) is an established treatment to improve cardiac function, a significant amount of patients do not experience noticeable improvement in their cardiac function. Optimal timing of the delay between atrial and ventricular pacing pulses (AV delay) is of major importance for effective CRT treatment and this optimum may differ between resting and exercise conditions. In this study the feasibility of haemodynamic measurements by the non-invasive finger plethysmographic method (Nexfin) was used to optimise the AV delay during exercise.

Methods and results

Thirty-one patients implanted with a CRT device in the last 4 years participated in the study. During rest and in exercise, stroke volume (SV) was measured using the Nexfin device for several AV delays. The optimal AV delay at rest and in exercise was determined using the least squares estimates (LSE) method. Optimisation created a clinically significant improvement in SV of 10 %. The relation between HR and the optimal AV delay was patient dependent.

Conclusion

A potential increase in SV of 10 % can be achieved using Nexfin for optimisation of AV delay during exercise. A considerable number of patients showed benefit with lengthening of the AV delay during exercise.     

Genetic Screening of the Canine Connexin 40 Gene in Dogs with Inherited Cardiac Conduction Defects

Connexin 40 (Cx40) is a gap-junction protein expressed in the heart where it mediates the coordinated electrical activation of the atria and ventricular conduction tissues, facilitates cell-to-cell adhesion, and provides pathways for direct intercellular communication. Recent studies have shown that Cx40 null mice have cardiac conduction abnormalities with a very high incidence of cardiac malformations in heterozygous (18%) and homozygous (33%) animals, indicating that Cx40 plays a vital role in cardiomorphogenesis. Since several inherited cardiac conduction defects have also been found in dogs, we hypothesized that the clinical findings are genetically linked to a tissue-specific mutation or mutations in the canine Cx40 gene. We therefore screened the Cx40 gene in dogs with inherited cardiac conduction defects for mutations. In this study, we have identified three heterozygous base changes (C384G, C402T, C837T) in the dogs screened and determined them to be synonymous mutations. These mutations, however, have recently been found in an unrelated group of normal dogs.     

先天性心脏病患儿介入封堵术治疗前后CRP、NT-proBNP、心率变异性的变化及与术后心功能的关系研究

摘要 目的：探讨先天性心脏病（CHD）患儿介入封堵术治疗前后C-反应蛋白（CRP）、N末端B型利钠肽原（NT-proBNP）、心率变异性（HRV）的变化及与术后心功能的关系。方法：选择2020年10月至2021年6月在本院行介入封堵术治疗的95例CHD患儿为研究对象,采用化学发光法检测血清CRP水平,采用电化学发光免疫技术检测血清NT-proBNP水平,采用24 h动态心电图及12导联同步心电图分析HRV指标,观察手术前后患儿的血清CRP、NT-proBNP水平及HRV指标变化,比较术后不同NYHA心功能分级患儿的血清CRP、NT-proBNP水平和HRV指标,分析患儿术前血清CRP水平、血清NT-proBNP水平、HRV指标与术后NYHA心功能分级的相关性。结果：介入封堵术后患儿血清CRP、NT-proBNP、LF/HF水平逐渐降低,术后3 d、术后1个月时均低于术前,术后1个月时均低于术后3 d时（P<0.025）;而TP、HF、LF、R-R、PNN50%、ASDNN、SDANN、SDNN、rMSSD水平逐渐升高,术后3 d、术后1个月时均高于术前,术后1个月时均高于术后3 d 时（P<0.025）。患儿术后3 d的血清CRP、NT-proBNP水平及LF/HF水平随着NYHA心功能分级的升高而升高,TP、HF、LF、R-R、PNN50%、ASDNN、SDANN、SDNN、rMSSD水平随着NYHA心功能分级的升高而降低（多有P＜0.05）。患儿术后3 d的NYHA心功能分级与治疗前血清CRP、NT-proBNP及LF/HF水平呈负相关,与TP、HF、LF、R-R、PNN50%、ASDNN、SDANN、SDNN、rMSSD水平呈正相关（P＜0.05）。结论：CHD患儿经介入封堵术治疗后,血清CRP、NT-proBNP及HRV指标变化明显,与术后NYHA心功能分级显著相关,血清CRP、NT-proBNP及HRV指标有望成为评估CHD患儿介入封堵术后预后的较敏感性指标。