Search

The use of CRT‐D devices with left ventricular (LV) sensing has created controversy about programming various parameters especially the left ventricular T wave protection (LVTP) designed to prevent the delivery of a pacing stimulus into the LV vulnerable period. Such devices are available from two manufacturers. This review focuses only on those provided by Biotronik. As the LVTP controls LV sensing, some investigators have advocated turning off the LVTP to prevent episodic desynchronization known a CRT pacing interrupt. However, LVTP off reduces but does not eliminate this type of desynchronization if triggering of an LV stimulus upon right ventricular sensing (RVs) is programmed on. Deactivation of the LVTP incurs loss of diagnostic data provided by CRT pacing interrupt itself. By choice, the occurrence of CRT pacing interrupt can be totally eliminated by appropriate programming of the LV upper rate interval, LVTP and triggering of an LV pacing event upon RVs. Various programmability options are available according to clinical circumstances. As a rule, clinical judgement must weigh the potential diagnostic benefit of preserving the LVTP capable of recording of episodic CRT pacing interrupt against the loss of diagnostic benefit when LVTP is programmed off (with or without triggering of an LV stimulus upon RVs). [ABSTRACT FROM AUTHOR]

Background: Cardiac resynchronization therapy-defibrillators (CRT-D) are devices established as treatment for symptomatic heart failure patients at risk of sudden cardiac death. Battery depletion poses a significant clinical and economic burden; extended service life may reduce costs because of generator changes and associated complications. Objective: This study estimated cost-savings associated with extended battery longevity in Medicare patients receiving CRT-D implantation. Methods: A decision tree was used to explore 3 battery capacities: 1.0 ampere-hours (Ah), 1.6Ah, and 2.1Ah. Yearly risk of all-cause mortality, device-related complications, and end of battery life were estimated. Over 6 years, estimated costs included device implantation, replacement, follow-up appointments, and complications. Results: The average total costs to Medicare over 6 years were $41,527, $48,515, and $56,647 per person (USD 2023) for the 2.1 Ah, 1.6 Ah, and 1.0 Ah, respectively. The total per-person replacement cost for the 1.0-Ah devices was more than 4 times that of the 2.1-Ah devices ($20,126 vs $5,006). When extrapolated to the total number of CRT-D implants over a 6-year period, the difference in costs between 2.1-Ah and 1.0-Ah battery capacity exceeded $500 million. Conclusion: Extended longevity CRT-D batteries demonstrate significant cost savings to Medicare over 6 years. These data indicate long-term economic considerations should be included in device selection.

Introduction: While supported by robust evidence and decades of clinical experience, right ventricular apical pacing for bradycardia is associated with a risk of progressive left ventricular dysfunction. Cardiac resynchronization therapy for heart failure with reduced ejection fraction can result in limited electrical resynchronization due to anatomical constraints and epicardial stimulation. In both settings, directly stimulating the conduction system below the atrio-ventricular node (either the bundle of His or the left bundle branch area) has potential to overcome these limitations. Conduction system pacing has met with considerable enthusiasm in view of the more physiological electrical conduction pattern, is rapidly becoming the preferred option of pacing for bradycardia, and is gaining momentum as an alternative to conventional biventricular pacing. Areas covered: This article provides a review of the current efficacy and safety data for both people requiring treatment for bradycardia and the management of heart failure with conduction delay and discusses the possible future roles for conduction system pacing in routine clinical practice. Expert opinion: Conduction system pacing might be the holy grail of pacemaker therapy without the disadvantages of current approaches. However, hypothesis and enthusiasm are no match for robust data, demonstrating at least equivalent efficacy and safety to standard approaches. [ABSTRACT FROM AUTHOR]

Heart failure (HF) is a complex medical condition characterized by both electrical and mechanical dyssynchrony. Both dyssynchrony mechanisms are intricately linked together, but the current guidelines for cardiac resynchronization therapy (CRT) rely only on the electrical dyssynchrony criteria, such as the QRS complex duration. This possible inconsistency may result in undertreating eligible individuals who could benefit from CRT due to their mechanical dyssynchrony, even if they fail to fulfill the electrical criteria. The main objective of this literature review is to provide a comprehensive analysis of the practical value of echocardiography for the assessment of left ventricular (LV) dyssynchrony using parameters such as septal flash and apical rocking, which have proven their relevance in patient selection for CRT. The secondary objectives aim to offer an overview of the relationship between septal flash and apical rocking, to emphasize the primary drawbacks and benefits of using echocardiography for evaluation of septal flash and apical rocking, and to offer insights into potential clinical applications and future research directions in this area. Conclusion: there is an opportunity to render resynchronization therapy more effective for every individual; septal flash and apical rocking could be a very useful and straightforward echocardiography resource. [ABSTRACT FROM AUTHOR]

Conduction system pacing (CSP) has emerged as a promising alternative to biventricular pacing (BVP) in patients with heart failure with reduced ejection fraction (HFrEF) and ventricular dyssynchrony, but its benefits are uncertain. In this study, we aimed to evaluate clinical outcomes of CSP vs BVP for cardiac resynchronization in patients with HFrEF. PubMed, Scopus, and Cochrane databases were searched for randomized controlled trials comparing CSP to BVP for resynchronization therapy in patients with HFrEF. Heterogeneity was examined with I2 statistics. A random-effects model was used for all outcomes. We included 7 randomized controlled trials with 408 patients, of whom 200 (49%) underwent CSP. Compared to BVP, CSP resulted in a significantly greater reduction in QRS duration (MD –13.34 ms; 95% confidence interval [CI] –24.32 to –2.36, P =.02; I2 = 91%) and New York Heart Association functional class (standardized mean difference [SMD] –0.37; 95% CI –0.69 to –0.05; P =.02; I2 = 41%), and a significant increase in left ventricular ejection fraction (mean difference [MD] 2.06%; 95% CI 0.16 to 3.97; P =.03; I2 = 0%). No statistical difference was noted for left ventricular end-systolic volume (SMD –0.51 mL; 95% CI –1.26 to 0.24; P =.18; I2 = 83%), lead capture threshold (MD –0.08 V; 95% CI –0.42 to 0.27; P =.66; I2 = 66%), and procedure time (MD 5.99 minutes; 95% CI –15.91 to 27.89; P =.59; I2 = 79%). These findings suggest that CSP may have electrocardiographic, echocardiographic, and symptomatic benefits over BVP for patients with HFrEF requiring cardiac resynchronization. [Display omitted] [ABSTRACT FROM AUTHOR]

Even with significant advancements in the treatment modalities for patients with heart failure (HF), the rates of morbidity and mortality associated with HF are still high. Various therapeutic interventions, including cardiac resynchronization therapy, Implantable Cardiovascular-Defibrillators, and left ventricular assist devices, are used for HF management. Currently, more research and developments are required to identify different treatment modalities to reduce hospitalization rates and improve the quality of life of patients with HF. In relation to this, various non-valvular catheter-based therapies have been recently developed for managing chronic HF. These devices target the pathophysiological processes involved in HF development including neurohumoral activation, congestion, and left ventricular remodeling. The present review article aimed to discuss the major transcatheter devices used in managing chronic HF. The rationale and current clinical developmental stages of these interventions will also be addressed in this review.

Conduction system pacing may revolutionize conventional pacemaker therapy. Both His- and left bundle branch area pacing (LBBAP) can prevent right ventricular pacing induced cardiomyopathy in bradycardia pacemaker indications, furtheron they might improve effectivity of cardiac resynchronization in heart failure patients with intraventricular conduction delay. Authors would like to present the potential benefits of LBBAP pacing in two patient-cases from the daily clinical scenario.

Copyright of Revista Española de Cardiología (18855857) is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: In patients with symptomatic Heart Failure (HF) and wide QRS duration, cardiac resynchronization therapy (CRT) causes reduction of morbidity and mortality. However, it's unclear which patient features predict short-term response to this device therapy. The research aimed to study which cases characteristics could expect short-term clinical and echocardiographic response to CRT. Methods: This prospective cohort study involved 40 patients indicated for CRT device. The study was conducted in the cardiology departments, faculty of medicine, Zagazig University, and Police hospital at the period from October 2018 to October 2020. Clinical, laboratory, electrocardiographic, and echocardiographic assessments were performed pre and six months after implantation. Results: Forty patients undergoing CRT implantation were included among which, 30 (75%) patients were considered responders after six months. From the present study, the responders to CRT were more frequently to be females with younger age than non -responders. Nonischemic HF, left bundle branch block (LBBB) morphology and New York Heart Association (NYHA) functional class III were significantly more frequent in responders. Furthermore, responders had significantly wider baseline QRS duration, smaller baseline LV diastolic and systolic dimension and volumes, greater ejection fraction, lower levels of brain natriuretic peptide (BNP), and more baseline intra-ventricular dyssynchrony. Conclusions: We concluded that pre-implantation independent Predictors of good CRT response are LBBB morphology, septal to posterior wall mechanical delay, wide QRS duration, interventricular mechanical delay, NYHA functional class III, and lower levels of BNP. Large scale study is recommended for further verification of study results. [ABSTRACT FROM AUTHOR]

Heart failure in patients with congenital heart disease (CHD) stems from unique causes compared with the elderly. Patients with CHD face structural abnormalities and malformations present from birth, leading to altered cardiac function and potential complications. In contrast, elderly individuals primarily experience heart failure due to age-related changes and underlying cardiovascular conditions. Cardiac resynchronization therapy (CRT) can benefit patients with CHD, although it presents numerous challenges. The complexities of CHD anatomy and limited access to appropriate venous sites for lead placement make CRT implantation demanding. [ABSTRACT FROM AUTHOR]

Cardiac resynchronization therapy is an essential tool for treating patients with heart failure in different types of dilatative cardiomyopathy with bundle branch block. This technique is wildly used with significant benefits in terms of quality of life and effort tolerability along with optimized medical therapy. In spite of its benefits, several factors may influence its efficacy such as etiology, lead position, or device settings. In some cases, the anatomical variance of the coronary sinus could create technical difficulties for advancing the left ventricular lead. This case report describes a female patient presenting with decompensated heart failure, known with complicated sclerosis multiplex and a fibrous tissue in the coronary sinus, which created a critical obstruction leading to impossibility to advance the left ventricular lead. This case underlines the importance of appropriate imaging investigation for optimal interventional approach in these difficult cases.

Background: Physiologic pacing through left bundle branch area pacing (LBBAP) has recently been shown to be a very promising alternative for cardiac resynchronization therapy (CRT) and to avoid pacing induced cardiomyopathy. However, it is not clear whether the position of LABBP lead may affect the clinical outcomes. Case Report: We here report a case of likely LBBAP induced worsening heart failure and cardiomyopathy reversed by re‐positioning of the pacing lead towards a more annular position. A 70‐year‐old male with a previous history of non‐ischemic dilated cardiomyopathy (ejection fraction 40%) who developed intermittent complete heart block and required permanent ventricular pacing. LBBAP was performed with the lead positioned to a position relatively far away from the tricuspid annulus (3.7 cm), due to difficulty in fixating the lead deep into the septum at a more annular position. One month post procedure, the patient's heart failure symptoms worsened, and his EF decreased to 31% despite good heart failure management. He underwent CRT upgrade with successful revision of the originally implanted LBBAP lead to a more annular position, using a deflectable delivery sheath. This resulted in further narrowing of the paced QRS duration from 135 to 106 ms. Two months post procedure, his heart failure symptoms improved by one functional class, and EF improved to 41% by echocardiogram. Conclusions: LBBAP may be harmful when the lead is placed too far away from the annulus and may cause paced induced cardiomyopathy. [ABSTRACT FROM AUTHOR]

Aims Left bundle branch area pacing (LBBAP) is a novel approach for cardiac resynchronization therapy (CRT), but the impact of myocardial substrate on its effect is poorly understood. This study aims to assess the association of cardiac magnetic resonance (CMR)–derived scar burden and the response of CRT via LBBAP. Methods and results Consecutive patients with CRT indications who underwent CMR examination and successful LBBAP-CRT were retrospectively analysed. Cardiac magnetic resonance late gadolinium enhancement was used for scar assessment. Echocardiographic reverse remodelling and composite outcomes (defined as all-cause death or heart failure hospitalization) were evaluated. The echocardiographic response was defined as a ≥15% reduction of left ventricular end-systolic volume. Among the 54 patients included, LBBAP-CRT resulted in a 74.1% response rate. The non-responders had higher global, septal, and lateral scar burden (all P < 0.001). Global, septal, and lateral scar percentage all predicted echocardiographic response [area under the curve (AUC): 0.857, 0.864, and 0.822; positive likelihood ratio (+LR): 9.859, 5.594, and 3.059; and negative likelihood ratio (−LR): 0.323, 0.233, and 0.175 respectively], which was superior to QRS morphology criteria (Strauss left bundle branch abnormality: AUC: 0.696, +LR 2.101, and −LR 0.389). After a median follow-up time of 20.3 (11.5–38.7) months, higher global, lateral and septal scar burdens were all predictive of the composite outcome (hazard ratios: 4.996, 7.019, and 4.741, respectively; P 's < 0.05). Conclusion Lower scar burden was associated with higher response rate of LBBAP-CRT. The pre-procedure CMR scar evaluation provides further useful information to identify potential responders and clinical outcomes. [ABSTRACT FROM AUTHOR]

Aims To assess the impact of MultiPoint™ Pacing (MPP) in cardiac resynchronization therapy (CRT) non-responders after 6 months of standard biventricular pacing (BiVP). Methods and results The trial enrolled 5850 patients who planned to receive a CRT device. The echocardiography core laboratory assessed CRT response before implant and after 6 months of BiVP; non-response to BiVP was defined as <15% relative reduction in left ventricular end-systolic volume (LVESV). Echocardiographic non-responders were randomized in a 1:1 ratio to receive MPP (541 patients) or continued BiVP (570 patients) for an additional 6 months and evaluated the conversion rate to the echocardiographic response. The characteristics of both groups at randomization were comparable. The percentage of non-responder patients who became responders to CRT therapy was 29.4% in the MPP arm and 30.4% in the BIVP arm (P = 0.743). In patients with ≥30 mm spacing between the two left ventricular pacing sites (MPP-AS), identified during the first phase as a potential beneficial subgroup, no significant difference in the conversion rate was observed. Conclusion Our trial shows that ∼30% of patients, who do not respond to CRT in the first 6 months, experience significant reverse remodelling in the following 6 months. This finding suggests that CRT benefit may be delayed or slowly incremental in a relevant proportion of patients and that the percentage of CRT responders may be higher than what has been described in short-/middle-term studies. MultiPoint™ Pacing does not improve CRT response in non-responders to BiVP, even with MPP-AS. [ABSTRACT FROM AUTHOR]

Background Cardiac resynchronization therapy (CRT) has been shown to benefit patients with heart failure and left bundle branch block (LBBB). However, CRT implantation is challenging when the superior venous access is not feasible. Case summary A 50-year-old man with a history of dilated cardiomyopathy and complete LBBB was referred to our hospital for CRT management. Angiography showed that the left and right brachiocephalic veins were occluded. Cardiac resynchronization therapy was finally implanted via the iliac vein. Follow-up echocardiography showed improved cardiac function, and the pacing system was functioning properly. Discussion The iliac vein access is feasible for CRT implantation with good stability, which can be a viable alternative to avoid unnecessary risk associated with thoracotomy and epicardial lead placement. [ABSTRACT FROM AUTHOR]

Copyright of Herzschrittmachertherapie und Elektrophysiologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background Patients with congenitally corrected transposition of the great arteries (ccTGA) are at risk of developing conduction disease and complete atrio-ventricular block and this risk increases after corrective cardiac surgery. However, the optimum pacing modality remains controversial. Case summary Twelve years after a double-switch surgery with ventricular septal defect correction, a 16-year-old ccTGA female was referred with an indication for cardiac resynchronization therapy. In the absence of coronary sinus (CS) or direct access to the conduction system, several therapeutic options were considered. Finally, using a three-dimensional navigation system and customized sheaths, a left bundle branch area pacing (LBBAP) lead was successfully implanted. The implantation resulted in stable pacing parameters and positive haemodynamic changes. At 9-month follow-up, pacing parameters were stable and the patient reported a significant improvement in quality of life. Discussion Cardiac resynchronization therapy in adults with repaired congenital heart disease remains challenging, especially in the absence of CS or direct access to the conduction system. In such a situation, LBBAP appears as an attractive alternative pacing modality. However, pre-operative management is critical to the success of the implantation. [ABSTRACT FROM AUTHOR]

Background: Conventional cardiac resynchronization therapy (CRT) involves implantation of a coronary sinus pacing lead through a delivery sheath, which typically requires a large venous access through a safe sheath of 9 French or greater in size. In patients who have very limited access due to scar tissue from previous implants or critical venous stenosis/closure, such large caliber access may not be available. Methods and Results: We report a case of CRT procedure in an 84‐year‐old male with a previous history of ischemic dilated cardiomyopathy (ejection fraction 40%) who was dependent on right ventricular pacing with worsening heart failure symptoms. The patient was incidentally discovered to have chronic total closure (CTO) of the left subclavian vein during the procedure. Although the CTO was crossed by a wire and dilated, the venous access was limited to a 7 French sheath which rendered conventional CRT through coronary sinus lead implant impossible. However, using the left bundle branch area pacing (LBBAP) technique which requires a smaller venous access, we were able to successfully achieve CRT. Postprocedure, the patient's paced QRS duration narrowed from 198 to 130 ms. His heart failure symptoms improved, and ejection fraction increased to 45% one‐month after the procedure. Conclusions: In patients with vascular access limited to a small caliber sheath not suitable for conventional CRT, LBBAP may help achieve procedural success and improve clinical outcome. [ABSTRACT FROM AUTHOR]

Aims To define a stepwise application of left bundle branch pacing (LBBP) criteria that will simplify implantation and guarantee electrical resynchronization. Left bundle branch pacing has emerged as an alternative to biventricular pacing. However, a systematic stepwise criterion to ensure electrical resynchronization is lacking. Methods and results A cohort of 24 patients from the LEVEL-AT trial (NCT04054895) who received LBBP and had electrocardiographic imaging (ECGI) at 45 days post-implant were included. The usefulness of ECG- and electrogram-based criteria to predict accurate electrical resynchronization with LBBP were analyzed. A two-step approach was developed. The gold standard used to confirm resynchronization was the change in ventricular activation pattern and shortening in left ventricular activation time, assessed by ECGI. Twenty-two (91.6%) patients showed electrical resynchronization on ECGI. All patients fulfilled pre-screwing requisites: lead in septal position in left-oblique projection and W paced morphology in V1. In the first step, presence of either right bundle branch conduction delay pattern (qR or rSR in V1) or left bundle branch capture Plus (QRS ≤120 ms) resulted in 95% sensitivity and 100% specificity to predict LBBP resynchronization, with an accuracy of 95.8%. In the second step, the presence of selective capture (100% specificity, only 41% sensitivity) or a spike-R <80 ms in non-selective capture (100% specificity, sensitivity 46%) ensured 100% accuracy to predict resynchronization with LBBP. Conclusion Stepwise application of ECG and electrogram criteria may provide an accurate assessment of electrical resynchronization with LBBP (Graphical abstract). [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Cardiac conduction system pacing provides physiological ventricular activation by directly stimulating the conduction system. This review describes the two types of conduction system pacing: His bundle pacing (HBP) and left bundle area pacing (LBAP). The most significant advantage of HB pacing is that it can provide a regular, narrow QRS; however, the disadvantages are challenging implantation and a high risk of re-intervention due to lead dislodgement and the development of high pacing threshold. LBAP provides optimum physiological activation of the left ventricle by engaging the left bundle/fascicular fibers. LBAP is more physiological than traditional RV apical pacing and could be an attractive alternative to conventional cardiac resynchronization therapy (CRT). The advantages of LBAP are a relatively more straightforward implantation technique than HBP, better lead stability and pacing thresholds. HBP and LBAP are more physiological than right ventricular pacing and may be used instead of conventional pacemakers. Both HBP and LBBP are being investigated as alternatives to conventional CRT. [ABSTRACT FROM AUTHOR]

Background: A better selection of patients with left bundle branch block (LBBB) might increase the response to cardiac resynchronization therapy (CRT). The aim of the study was to investigate the association between the Strauss criteria, absence of S wave in V5-V6, the Selvester score and response to CRT.Methods and Results: The retrospective analysis included all consecutive patients having undergone implantation of biventricular defibrillators in primary prevention between 2018 and 2020. The final analysis included 236 patients (mean age 69.7 ± 9.9; 77.5% of males). The Strauss criteria were significantly associated with CRT response (p < 0.01) with a sensitivity of 71.3% and specificity of 64.1%. The Strauss criteria along with the absence of S wave in V5 and V6 showed a sensitivity of 56.7%, a specificity of 82.6% and a positive predictive value of 90.5%. The Selvester score was significantly and inversely associated with CRT response (OR 0.818, 95% CI 0.75-0.89; p < 0.001). The multivariable model showed that left ventricular ejection fraction (LVEF) and QRS duration (≥140 ms in males and ≥ 130 ms in females) were independently associated with CRT response (respectively OR 0.92, CI 95% 0.86-0.98, p = 0.01 and OR 3.70, CI 95% 1.12-12.21, p = 0.03).Conclusions: Strauss criteria, especially in association with absence of S wave in V5 and V6, were able to increase specificity and positive predictive value for predicting CRT response. The Selvester score was inversely associated with CRT response. Finally, LVEF and QRS duration were independently associated with echocardiographic response to CRT. [ABSTRACT FROM AUTHOR]

Background: In this study, we sought to evaluate whether concomitant AV node ablation through the same venous access can be safely performed during cardiac resynchronization therapy (CRT) device implant using the left bundle branch area (LBBA) pacing technique and compared the acute procedural outcomes to those using the conventional approach. Methods: Ten consecutive patients with systolic heart failure and atrial fibrillation (AF) with uncontrolled ventricular rates underwent CRT through LBBA pacing. AV node ablation was performed through the left axillary vein after implantation of the RV lead, before LBBA pacing lead implant. The LBBA pacing lead was subsequently implanted and connected to the new CRT device. The acute outcomes were compared to the last 10 conventional CRT procedures followed by AV node ablation through the femoral vein. Results: LBBA pacing and AV node ablation through the left axillary vein was successful in all patients. The total procedure time was 124+/-17min in the conventional group and 81+/-24 min in the study group (p<0.01). The QRS duration was shorter (114+/-10ms vs 134+/- 12ms, p<0.01) and the left ventricular pacing threshold was lower in the LBBA pacing group (0.64±0.26 vs 1.9±1.3 v, p=0.02). No major complications were noticed in either group. Conclusion: Concomitant AV node ablation through the left axillary approach during CRT implantation using LBBA pacing is safe, feasible and resulted in a shorter QRS duration, reduced LV pacing threshold and marked reduction in the total procedure time compared to the conventional approach of CS pacing with AV node ablation through the femoral vein. [ABSTRACT FROM AUTHOR]

Background: Optimal management of checkpoint inhibitor-induced complete heart block is unknown. Previous reports showed relatively high incidence of pacing failure due to the co-existing myocarditis., Case Summary: A 71-year-old male with a prior history of stage IV metastatic squamous cell lung cancer presents was admitted for dyspnoea and hypotension 10 days after checkpoint inhibitor treatment using pembrolizumab. He was found to have myocarditis, third-degree AV block, severe left ventricular systolic dysfunction with EF 35%, and required pressure support. A dual chamber pacemaker using left bundle branch area pacing (LBBAP) was urgently placed that immediately improved his haemodynamics. Both the cathode and anode were able to capture the ventricle at different pacing outputs. The patient was taken off all intravenous pressors and successfully transferred to a larger centre for further management of the myocarditis with no further arrhythmia or hypotension., Discussion: In conclusion, because of the unique ability to capture a large amount of myocardium from both the tip and ring electrodes as well as the ability to deliver cardiac resynchronization therapy, LBBAP may be the preferred pacing strategy in patients who develop complete heart block due to checkpoint inhibitor-induced myocarditis., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Aims: Cardiac resynchronization therapy (CRT) via biventricular (BIV) pacing is indicated in patients with heart failure (HF), reduced ejection fraction, and prolonged QRS duration. Quadripolar leads and multipoint pacing (MPP) allow multiple left ventricle (LV) sites pacing. We aimed to assess the clinical benefit of MPP in patients who do not respond to standard BIV pacing., Methods and Results: Overall, 3724 patients were treated with standard BIV pacing. After 6 months, 1639 patients were considered as CRT non-responders (echo-measured relative reduction in LV end-systolic volume (LVESV) < 15%) and randomized to MPP or BIV. We analysed 593 randomized patients (291 MPP, 302 BIV), who had BIV pacing >97% of the time before randomization and complete 12 months of clinical and echocardiographic data. The endpoint composed of freedom from cardiac death and HF hospitalizations and by LVESV relative reduction ≥15% between randomization and 12 months occurred more frequently in MPP [96/291 (33.0%)] vs. BIV [71/302 (23.5%), P = 0.0103], which was also confirmed at multivariate analysis (hazard ratio = 1.55, 95% confidence interval = 1.02-2.34, P = 0.0402 vs. BIV). HF hospitalizations occurred less frequently in MPP [14/291 (4.81%)] vs. BIV [29/302 (9.60%), incidence rate ratio = 50%, P = 0.0245]. Selecting patients with a large (>30 ms) dispersion of interventricular electrical delay among the four LV lead dipoles, reverse remodelling was more frequent in MPP [18/51 (35.3%)] vs. BIV [11/62 (17.7%), P = 0.0335]., Conclusion: In patients who do not respond to standard CRT despite the high BIV pacing percentage, MPP is associated with lower occurrence of HF hospitalizations and higher probability of reverse LV remodelling compared with BIV pacing., Competing Interests: Conflict of interest: Dr Rinaldi has received research funding and/or consultation fees from Abbott, Medtronic, Boston Scientific, Spectranetics, EBR Systems, and MicroPort outside of the submitted work. Dr Leclercq has received honoraria from Abbott, Medtronic, Boston Scientific, Biotronik, and Livanova. Dr Burri has received institutional fellowship support and research grants from Abbott. Dr Sperzel serves as a consultant to Abbott, in addition to receiving honoraria and currently conducting research sponsored by Abbott. Dr Thibault has received research support and honoraria from Abbott and Medtronic. Dr Lee, Ms Lin. and Mr Grammatico are employees of Abbott. All remaining authors have declared no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Background: It is unknown whether cardiac resynchronization therapy (CRT) would improve or halt the progression of heart failure (HF) in patients with mild to moderately reduced ejection fraction (HFmmrEF) and left bundle branch block (LBBB)., Objective: This study aimed to investigate the outcomes of CRT in patients with HFmmrEF and left ventricular conduction delay., Methods: A prospective, randomized clinical trial sponsored by the National Heart, Lung, and Blood Institute included 76 patients who met the study inclusion criteria (left ventricular ejection fraction [LVEF] of 36%-50% and LBBB). Patients received CRT-pacemaker and were randomized to CRT-OFF (right ventricular pacing 40 beats/min) or CRT-ON (biventricular pacing 60-150 beats/min). At a 6-month follow-up, pacing programming was changed to the opposite settings. New York Heart Association class, N-terminal pro-brain natriuretic peptide levels, and echocardiographic variables were collected at baseline, 6 months, and 12 months. The primary study end point was the left ventricular end-systolic volume (LVESV) change from baseline, and the primary randomized comparison was the comparison of 6-month to 12-month changes between randomized groups., Results: The mean age of the patients was 68.4 ± 9.8 years (male, 71%). Baseline characteristics were similar between the 2 randomized groups (all P > .05). In patients randomized to CRT-OFF first, then CRT-ON, LVESV was reduced from baseline only after CRT-ON (baseline, 116.1 ± 36.5 mL; CRT-ON, 87.6 ± 26.0 mL; P < .0001). The randomized analysis of LVEF showed a significantly better change from 6 to 12 months in the OFF-ON group (P = .003). LVEF was improved by CRT (baseline, 41.3% ±.7%; CRT-ON, 46.0% ± 8.0%; P = .002). In patients randomized to CRT-ON first, then CRT-OFF, LVESV was reduced after both CRT-ON and CRT-OFF (baseline, 109.8 ± 23.5 mL; CRT-ON, 91.7 ± 30.5 mL [P < .0001]; CRT-OFF, 99.3 ± 28.9 mL [P = .012]). However, the LVESV reduction effect became smaller between CRT-ON and CRT-OFF (P = .027). LVEF improved after both CRT-ON and CRT-OFF (baseline, 42.7% ± 4.3%; CRT-ON, 48.5% ± 8.6% [P < .001]; CRT-OFF, 45.9% ± 7.7% [P = .025])., Conclusion: CRT for patients with HFmmrEF significantly improves LVEF and ventricular remodeling after 6 months of CRT. The study provides novel evidence that early CRT benefits patients with HFmmrEF with LBBB., Competing Interests: Disclosures The authors have no conflicts of interest to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Even with significant advancements in the treatment modalities for patients with heart failure (HF), the rates of morbidity and mortality associated with HF are still high. Various therapeutic interventions, including cardiac resynchronization therapy, Implantable Cardiovascular-Defibrillators, and left ventricular assist devices, are used for HF management. Currently, more research and developments are required to identify different treatment modalities to reduce hospitalization rates and improve the quality of life of patients with HF. In relation to this, various non-valvular catheter-based therapies have been recently developed for managing chronic HF. These devices target the pathophysiological processes involved in HF development including neurohumoral activation, congestion, and left ventricular remodeling. The present review article aimed to discuss the major transcatheter devices used in managing chronic HF. The rationale and current clinical developmental stages of these interventions will also be addressed in this review., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Mody, Nee Sheth, Dash, Mody, Agrawal, Monga, Rastogi and Munjal.)

Thanks to technological advancements, the improvement in the quality of life, and a decline in birth rates, the average age of the world’s population is increasing from decade to decade. It is estimated that by the year 2030, the percentage of people aged 65 and older will rise from 6.9% to 12.0%, and particularly in developing countries1 . Pacemakers are electrical generators designed to mimic a customized pulse in terms of rate (frequency) and output power. While the pulse delivery can be temporary or permanent, the device’s function is assessed and adjusted through interrogation, which includes the stimulation rate, pulse width, and voltage. These devices are typically categorized as external and internal. External pacemakers are commonly used as a temporary measure for cardiac stimulation when a temporary cause of conduction disturbances is suspected (e.g., hyperkalemia), while internal pacemakers are implanted and represent a permanent solution. The primary indications for permanent electrical stimulation are sinus node disease (I), atrioventricular conduction disorders (I), and recurrent syncope (IIa/C)2. The Implantable Cardioverter Defibrillator (ICD) is a device that, in addition to its pacing function, also has the capability for intracardiac defibrillation. Since its inception in the 1950s, distinguishing ICDs from ‘pure’ pacemakers has become more challenging because every ICD includes a pacing function. Devices for cardiac resynchronization therapy, or biventricular pacing (CRT-P), and those with an integrated defibrillation lead (CRT-D), are used in the treatment of heart failure in a specific patient population where improvement in cardiac function and quality of life is expected through biventricular electrical stimulation2. In the last two decades (Figures 1-3), approximately 1300 pacemakers (120-140 per year) have been implanted at General Hospital “Dr. Josip Benčević”, Slavonski Brod, with 58% being single-chamber stimulation devices (VVI), 154 ICD devices, 45 CRT (P and D) devices, and a dozen loop recorders. Observing new scientific advancements and their application in everyday clinical practice is of paramount importance for the proper patient care. In line with this, at our institution, starting in the fall of 2023, 5 devices with conduction system stimulation have been implanted. [ABSTRACT FROM AUTHOR]

Background: Chronic heart failure (CHF) is a complex syndrome characterized by an abnormal neurohormonal activation, including arginine vasopressin (AVP). Copeptin is an indicator of AVP activation, which levels are elevated in CHF and have prognostic importance. Cardiac resynchronization therapy (CRT) is an important device therapy for patients with advanced CHF, left ventricular (LV) systolic dysfunction and evidence of electromechanical dyssynchrony. The aim of the present study was to determine the possible relationship between CRT and serum copeptin levels. Methods: We included CRT patients with ischemic as well as nonischemic etiology of CHF. The levels of copeptin were measured at baseline and 12 months respectively after CRT implantation. Echocardiography was also performed pre and 12 months post CRT implantation. A CRT response was defined as a = 15% reduction in LV end-systolic volume (LVESV). Results: The study population consisted of 41 patients. The mean copeptin level was 20.50 ± 15.77 pmol/l. Copeptin levels positively correlated with New York Heart Association class, left atrial diameter, creatinine levels and NT-proBNP levels. CRT responders have significant reduction in copeptin levels from baseline to 12 months (from 16.96 ± 12.80 pmol/l to 6.20 ± 6.44 pmol/l, p < 0.001). No significant changes in copeptin levels were observed in CRT nonresponders. Reduction > 45% in copeptin levels was significantly associated with CRT-response (OR 6.72, 95% CI 1.01 - 18.11, p = 0.045). Fig. 1, Tab. 2, Ref. 23, on-line full text (Free, PDF) www.cardiologyletters.sk Conclusion: The copeptin serum levels can be a useful biomarker in the evaluation of the CRT response. [ABSTRACT FROM AUTHOR]

Background: The results of previous studies evaluating the effects of cardiac resynchronization therapy (CRT) on myocardial blood flow (MBF) and their relation with the response to CRT are conflicting. Materials and Methods: Sixty-one patients diagnosed with idiopathic dilated cardiomyopathy (IDC), a functional capacity (New York Heart Association [NYHA]) Class II or III, and left bundle branch block (LBBB) (QRS width >150 ms) were enrolled in the study. We aimed to evaluate the effects of CRT on MBF in patients with IDC and LBBB by coronary flow reserve (CFR) measurements and thereby tried to predict the responders. Results: Sixty-one patients with IDC were enrolled. CFR and hyperemic fractional flow reserve (FFR) increased after CRT. The only parameter affecting the increase in CFR was the change in FFR after CRT. Then, 44 patients who responded to the CRT treatment at 6 months were compared with 17 patients who did not. Left ventricle outflow tract time-velocity integral (LVOT-TVI), stroke volume (SV) and cardiac output index (COi) was detected significantly higher also left ventricular end-diastolic pressure (LVEDP) was lower in the CRT responders. However, there were no significant differences in coronary flow velocity measurements between the two groups. Moreover the regression analysis revealed that the baseline NYHA class, LVOT TVI, SV, COi, and LVEDP, which were changed due to increased blood flow after CRT implantation, is not associated with response to CRT. Conclusions: Our results suggest that MBF increased after CRT in patients with IDC probably by improving microvascular functions. However, the response to CRT treatment is not related to the changes in the coronary blood flow velocities after CRT.

His bundle pacing is increasingly used to avoid chronic right ventricular pacing, and electrically resynchronize ventricular activation by narrowing or normalizing the QRS interval in left and right bundle branch block. The mechanisms by which this occurs remain poorly understood. In this review, the proposed mechanisms and evidence supporting them are discussed. Also discussed are aspects of mechanisms that are not completely supported by the evidence. We also review the differences and physiological bases for direct vs. indirect His bundle capture, and the physiological mechanisms for QRS narrowing vs. normalization following His bundle pacing.

Aims: To determine if remotely monitored physiological data from cardiac implantable electronic devices (CIEDs) can be used to identify patients at high risk of mortality.Methods and Results: This study evaluated whether a risk score based on CIED physiological data (Triage-Heart Failure Risk Status, 'Triage-HFRS', previously validated to predict heart failure (HF) events) can identify patients at high risk of death. Four hundred and thirty-nine adults with CIEDs were prospectively enrolled. Primary observed outcome was all-cause mortality (median follow-up: 702 days). Several physiological parameters [including heart rate profile, atrial fibrillation/tachycardia (AF/AT) burden, ventricular rate during AT/AF, physical activity, thoracic impedance, therapies for ventricular tachycardia/fibrillation] were continuously monitored by CIEDs and dynamically combined to produce a Triage-HFRS every 24 h. According to transmissions patients were categorized into 'high-risk' or 'never high-risk' groups. During follow-up, 285 patients (65%) had a high-risk episode and 60 patients (14%) died (50 in high-risk group; 10 in never high-risk group). Significantly more cardiovascular deaths were observed in the high-risk group, with mortality rates across groups of high vs. never-high 10.3% vs. <4.0%; P = 0.03. Experiencing any high-risk episode was associated with a substantially increased risk of death [odds ratio (OR): 3.07, 95% confidence interval (CI): 1.57-6.58, P = 0.002]. Furthermore, each high-risk episode ≥14 consecutive days was associated with increased odds of death (OR: 1.26, 95% CI: 1.06-1.48; P = 0.006).Conclusion: Remote monitoring data from CIEDs can be used to identify patients at higher risk of all-cause mortality as well as HF events. Distinct from other prognostic scores, this approach is automated and continuously updated. [ABSTRACT FROM AUTHOR]

QT interval prolongation is a known risk factor for development of malignant ventricular arrhythmias. Measurement of the QT interval is difficult in the setting of ventricular pacing (VP), which can prolong depolarization and increase the QT interval, overestimating repolarization time. VP and cardiac resynchronization therapies have become commonplace in modern cardiac care and may contribute to repolarization heterogeneity and subsequent increased risk for ventricular arrhythmias including Torsades de Pointes. It is imperative for the clinician caring for acutely ill cardiac patients to understand the relationship between QT interval prolongation, both drug-induced and pacing-induced, and repolarization changes with subsequent ventricular arrhythmia risk. In this review, we discuss the components of QT interval assessment for arrhythmogenic risk including arrhythmogenic QT prolongation, methods for adjusting the QT interval to identify repolarization changes, methods to adjust for heart rate, and propose a framework for medication management to assess for drug-induced long QT syndrome in patients with VP. [ABSTRACT FROM AUTHOR]

Background: Cardiac resynchronization therapy is known to promote symptom improvement, increased survival, and decreased hospitalizations for heart failure. However, one third of patients on cardiac resynchronization therapy may not achieve any clinical improvement. One of the factors for the lack of improvement is an inadequate adjustment of the cardiac device programming, because such adjustments are commonly made at rest. Cardiac resynchronization therapy optimization can be done by adjusting the cardiac resynchronizer during cardiopulmonary exercise testing, this allow the program to align with the functional class of the patient, thus maintaining atrioventricular synchronism and biventricular pacing according to the chronotropic response to effort. However, there is a lack of protocols that propose device adjustment through cardiopulmonary exercise testing and that evaluate the response to its readjustment. Objective: To develop a cardiac resynchronizer readjustment protocol using cardiopulmonary exercise testing. Methods: This was a randomized controlled clinical trial to evaluate the effectiveness of device readjustment during maximal exercise. The variables used to measure the degree of response to readjustment will be: Functional capacity by the six-minute walk test, life quality by means of the Minessota questionnaire and sleep quality by means of the pittsburg. Participants will be divided into two groups (control and intervention group), then, the six-minute walktest will be applied, followed by life quality and sleep evaluation. The cardiopulmonary test will be the last proposed activity and will not be performed on the same day as the other evaluations. After three months, they will be submitted again to the same testes mentioned previously. During the initial evaluation by cardiopulmonary testing, the components of the intervention group will undergo cardiac resynchronization readjustment by means of a protocol. Results: We hope that the intervention designed by the protocol can contribute to the improvement of functional capacity, quality of life and sleep. [ABSTRACT FROM AUTHOR]

Right ventricular (RV) resynchronization therapy (CRT) with stimulation electrode implantation in the latest activation area guided by a high‐density electroanatomic activation map was successfully performed in a patient with repaired tetralogy of Fallot (rToF), severe pulmonary regurgitation (PR), and severe dysfunction and dilatation of the right ventricle. An improvement in his clinical condition and intraventricular synchrony was achieved. There is a mechanical‐electrical interaction in the right ventricle of patients with rToF; therefore, RV CRT in selected cases may be beneficial. Electroanatomic activation mapping can help achieve maximum clinical benefit by identifying the optimal stimulation site. [ABSTRACT FROM AUTHOR]

Background: No real-world large database associates lower rate limit (LRL) programming and survival of subjects with cardiac resynchronization therapy-defibrillators (CRT-Ds).Objective: The purpose of this study was to test the hypothesis that lower LRL programming is independently associated with survival, and that LRL and heart rate score (HrSc) are associated.Methods: All dual-chamber CRT-D devices in the Remote Patient Monitoring (RPM) ALTITUDE database (2006-2011) were queried. Baseline HrSc was defined as the percentage of all atrial sensed and paced beats in the tallest 10-beat histogram bin postimplant. LRL was assessed during repeated RPM uploads. Using a Cox model multivariable analysis, relationships between LRL, survival, HrSc, and other variables were evaluated. Survival was determined by query of death indices.Results: Data analyzed included 61,881 subjects (mean follow-up 2.9 years). LRL ranged from 40 to 85 bpm. Baseline lower LRL was associated with younger age, less atrial fibrillation, female sex, and lower HrSc (P <.001 for all covariates). Lower LRL was associated with improved survival, with LRL 40 associated with the largest survival benefit. This was significant for all 3 HrSc subgroups (P <.001). An interaction between HrSc and LRL was observed, with the largest survival difference between HrSc groups observed at LRL-40 (P <.001).Conclusion: LRL programming and HrSc were associated, and lower values of both were associated with improved survival in a large database of CRT-D subjects. Relationships between survival, LRL programming, and HrSc merit further study. [ABSTRACT FROM AUTHOR]

Purpose: We hypothesized that data in manufacturers' product performance reports (PPRs) can provide clinically valuable ICD and cardiac resynchronization defibrillator (CRT-D) reliability and longevity information.Methods: Data were obtained from 2019 PPRs. Kaplan-Meier (K-M) probabilities of freedom from malfunction, normal battery depletion (NBD), and NBD + malfunction were calculated for ICD and CRT-D pulse generators (PGs) with LiMnO2 or LiSVO/CFx batteries marketed in the USA from 2010 to 2019 and compared using the log-rank test. Malfunctions (MAL) included PGs that were found outside specifications.Results: Study population included 1,149,803 ICD and CRT-D PGs: Abbott (ABT; 35.1%), Biotronik (BIO; 4.6%), Boston Scientific (BSC; 23.5%), and Medtronic (MDT; 36.9%). Significant differences in reliability (p < 0.001), defined by freedom from MAL, were found between manufacturers; the majority of 6808 MAL occurred in ABT devices (n = 4045; 59.4%), followed by BSC (n = 2384; 35.0%), MDT (n = 338;5.0%), and BIO (n = 41; 0.6%). Battery failure (n = 890; 57.9%) was the most common cause of MAL compromising therapy; analysis of unique ABT battery MAL-indicated problem appeared a year prior to advisory. Significant differences (p < 0.001) in battery longevity, as defined by freedom from NBD, were found between manufacturers. Overall performance (freedom from NBD + MAL) favored BSC for CRT-D PGs and MDT and BIO for ICDs. BSC subcutaneous ICD reliability was inferior to its transvenous ICD (p < 0.001).Conclusion: PPRs contain valuable data that can be aggregated and analyzed to inform physicians. Differences in product reliability exist between manufacturers. Battery longevity has improved, but MAL have significantly impacted performance. PPR data may be useful for assessing product problems and new technology. [ABSTRACT FROM AUTHOR]

Copyright of Herz is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: In patients with uncontrolled atrial fibrillation, atrioventricular (AV) node ablation after permanent His bundle pacing (p‐HBP) could be a therapeutic option for heart rate (HR) control. We aimed to demonstrate the advantages of AV node ablation with p‐HBP, and to describe its effectiveness and safety. Methods: This descriptive observational study included patients with uncontrolled permanent atrial arrhythmias who were candidates for HR control (January 2019 to July 2020) and underwent p‐HBP and AV node ablation. Results: A total of 39 patients were included. The median left ventricular ejection fraction (LVEF) was 55% (45–60); 46.1% in NYHA class II and 43.6% in NYHA class III. p‐HBP was achieved in 92.3% (n = 36), and AV node ablation was successfully performed in all patients. The LVEF improved in patients with reduced LVEF (baseline, 35% [23.8–45.3%]; follow‐up, 40% [35–56.5%], p < 0.05); the NYHA class also showed improvement (baseline, 71.4% patients in class III and 7.1% in class II, and at follow‐up, 78.6% patients in class II and 14.3% in class I). In patients with previously normal LVEF, LVEF remained stable; nevertheless, a significant NYHA class improvement was observed (baseline, 63.6% class II and 31.8% class III patients; follow‐up, 54.5% class I and 45.5% class II patients). The His thresholds and lead parameter values did not significantly change during the follow‐up and remained stable. Conclusions: In patients with uncontrolled atrial arrhythmias who underwent AV node ablation after p‐HBP, the NYHA class improved and the LVEF increased in those with reduced baseline LVEF. The values of pacing parameters were acceptable and remained stable during the follow‐up. [ABSTRACT FROM AUTHOR]

Cardiovascular implantable electronic devices (CIED) are effective and important components of modern cardiovascular care. Despite the dramatic improvements in the functionality and reliability of these devices, over time patients are at risk for developing several morbidities, the most feared of which are local and systemic infections. Despite significant financial investment and aggressive therapy with hospitalization, intravenous antibiotics, and transvenous lead extraction, the outcomes include a 1-year mortality rate as high as 25%. This risk of infection has increased over time, likely due to the increased complexity of the surgical interventions required to insert and replace these devices. The only way to reduce this morbidity and mortality is to prevent these infections, and other than preoperative antibiotics, there were little data supporting effective therapy until the WRAP-IT trial provided randomized data showing that pocket infections can be reduced by 60% at 12 months and major CIED infections reduced by 40% at 1 year with the use of the absorbable antibiotic eluting envelope in patient CIED procedures at high risk of infection. Not all CIED procedures are at high risk of infection and justify the use of the envelope, but cost-effectiveness data support the use of the antibiotic envelope particularly in patients with defibrillator replacements, revisions, and upgrades, such as to a resynchronization device and in patients with prior CIED infection, history of immunocompromise, two or more prior procedures, or a history of renal dysfunction. [ABSTRACT FROM AUTHOR]

Background: The implantation rates of cardiac implantable electronic devices have steadily increased, accompanied by a steeper rise of device related infections (DRI). Hypothesis: The prevalence of DRI for cardiac resynchronization therapy (CRT) is higher in clinical practice than reported previously, even at a university hospital, and likely higher than reported to the national device registry. Methods: Electronic medical records of consecutive patients undergoing a CRT procedure between January 2016 and December 2017 were analyzed. Clinical history, procedure related variables and complications were reviewed by specialists in cardiology and infectious diseases. Results: A total of 171 patients, mean aged 74 years, 138 males (80.7%) were included. Twelve DRI occurred in 10 patients during mean 2.5 years follow‐up, giving a prevalence of 7% (incidence of 29/1000 person‐years). Reoperation, pocket haematoma, ≥3 procedures, previous device infection and indwelling central venous line were the strongest predictive factors according to univariate analysis. Out of 63/171 (36.8%) major complications, 31(49.2%) were lead‐related. There were 49/171 (28.7%) reoperations and 15/171 (8.8%) minor complications. The number major complications and DRI reported to the national device registry were 7/171 (4.1%) and 2/171 (0.6%), respectively, reflecting a 5‐fold underreporting. Conclusions: The high rate of CRT device infections is in sharp contrast to those reported by others and to the national device registry. Although a center specific explanation cannot be excluded, the high rates highlight a major issue with registries, reinforcing the need for better surveillance and automatic reporting of device related complications. [ABSTRACT FROM AUTHOR]