Network meta-analysis of His bundle, biventricular, or right ventricular pacing as a primary strategy for advanced atrioventricular conduction disease with normal or mildly reduced ejection fraction

His Bundle Pacing and Left Bundle Branch Pacing in Patients with Heart Failure

BACKGROUND

His bundle pacing (HBP) and left bundle branch pacing (LBBP) are emerging therapies for patients with heart failure and conduction disorders, offering potential advantages over traditional pacing methods. These approaches aim to restore physiological conduction and improve cardiac function more effectively.

OBJECTIVE

This study aims to evaluate the efficacy and safety of HBP and LBBP in patients with heart failure and conduction disturbances, comparing these techniques to conventional pacing.

METHODS

A comprehensive review of recent studies and clinical trials was conducted, focusing on the performance of HBP and LBBP in improving cardiac function, reducing QRS duration, and enhancing overall patient outcomes. The analysis includes data on clinical efficacy, procedural safety, and long-term benefits associated with these pacing modalities.

RESULTS

Both HBP and LBBP have demonstrated significant improvements in cardiac function and clinical outcomes compared to conventional pacing. HBP effectively restores physiological conduction with improved synchronization and a reduction in QRS duration. LBBP has shown enhanced left ventricular activation, leading to better overall cardiac performance. Both techniques have been associated with a lower incidence of complications and a higher success rate in achieving optimal pacing thresholds.

CONCLUSIONS

HBP and LBBP offer promising alternatives to traditional pacing for patients with heart failure and conduction disorders. These advanced pacing strategies provide superior clinical outcomes and improved cardiac function with reduced risk of complications. Further research and clinical trials are needed to fully establish the long-term benefits and safety profiles of these techniques in diverse patient populations.

2024 HRS expert consensus statement on arrhythmias in the athlete: Evaluation, treatment, and return to play

Youth and adult participation in sports continues to increase, and athletes may be diagnosed with potentially arrhythmogenic cardiac conditions. This international multidisciplinary document is intended to guide electrophysiologists, sports cardiologists, and associated health care team members in the diagnosis, treatment, and management of arrhythmic conditions in the athlete with the goal of facilitating return to sport and avoiding the harm caused by restriction. Expert, disease-specific risk assessment in the context of athlete symptoms and diagnoses is emphasized throughout the document. After appropriate risk assessment, management of arrhythmias geared toward return to play when possible is addressed. Other topics include shared decision-making and emergency action planning. The goal of this document is to provide evidence-based recommendations impacting all areas in the care of athletes with arrhythmic conditions. Areas in need of further study are also discussed.

Clinical effectiveness of pharmacological interventions for managing chronic migraine in adults: a systematic review and network meta-analysis

BACKGROUND

Chronic migraine can be a profoundly disabling disorder that may be treated with preventive medications. However, uncertainty remains as to which preventive medication is the most effective. We present a network meta-analysis to determine the effectiveness and rank of preventive drugs for chronic migraine in adults.

METHODS

We identified, reviewed, and extracted data from randomised controlled trials (RCTs) of preventive drugs for chronic migraine with at least 200 participants. Data were analysed using network meta-analysis.

FINDINGS

We included 12 RCTs of six medications (Eptinezumab, Erenumab, Fremanezumab, Galcanezumab, Onabotulinumtoxin A, and Topiramate) compared to placebo or each other. All drugs effectively reduced monthly headache and migraine days compared with placebo. The most effective drug for monthly headache days was Eptinezumab 300mg, with a mean difference of -2.46 days, 95% Credible Interval (CrI): -3.23 to -1.69. On the Surface Under the Cumulative Ranking Area (SUCRA) analysis, the probability that Eptinezumab 300mg was ranked highest was 0.82. For monthly migraine days, the most effective medication was Fremanezumab-monthly, with a mean difference: -2.77 days, 95% CrI: -3.36 to -2.17, and 0.98 probability of being ranked the highest. All included drugs, except Topiramate, improved headache-related quality of life. No eligible studies were identified for the other common preventive oral medications such as Amitriptyline, Candesartan, and Propranolol. The main reasons were that the studies did not define chronic migraine, were undertaken before the definition of chronic migraine, or were too small.

INTERPRETATION

All six medications were more effective than the placebo on monthly headache and migraine days. The absolute differences in the number of headache/migraine days are, at best, modest. No evidence was found to determine the relative effectiveness of the six included drugs with other oral preventive medications.

REGISTRATION

PROSPERO (number CRD42021265990).

Outcomes of left bundle branch area pacing compared to His bundle pacing as a primary pacing strategy: Systematic review and meta-analysis

BACKGROUND

Novel pacing technologies, such as His bundle pacing (HBP) and left bundle branch area pacing (LBBaP), have emerged to maintain physiological ventricular activation. We investigated the outcomes of LBBP with HBP for patients requiring a de novo permanent pacing.

METHODS AND RESULTS

Systematic review of randomized clinical trials and observational studies comparing LBBaP with HBP until March 01, 2023 was performed. Random and fixed effects meta-analyses of the effect of pacing technology on outcomes were performed. Study outcomes included pacing metrics, QRS duration, lead revision, procedure parameters, all-cause mortality and heart failure hospitalization (HFH). Overall, 10 studies with 1596 patients were included. Implant success rate was higher in LBBaP compared with HBP (RR 1.24, 95% CI: 1.08 to 1.42, p = .002). LBBaP was associated with lower capture threshold at implantation (mean difference (MD) -0.62 V, 95% CI: -0.74 to -0.51 V, p < .0001) and at follow-up (MD -0.74 V, 95% CI: -0.96 to -0.53, p < .0001), shorter procedure duration (MD -14.66 min, 95% CI: -23.54 to -5.78, p = .001) and shorter fluoroscopy time (MD -4.2 min, 95% CI: -8.4 to -0.0, p = .05). Compared with HBP, LBBaP was associated with a decreased risk of all-cause mortality (RR: 0.50, 95% CI: 0.33 to 0.77, p = .002) and HFH (RR: 0.57, 95% CI: 0.33 to 1.00, p = .05). No statistical differences were found in lead revisions and QRS duration before and after pacing.

CONCLUSION

This meta-analysis found that LBBaP was superior to HBP regarding pacing metrics and implant success rate as an initial pacing strategy, although absence of head-to-head randomized comparison warrants caution in interpretation of the results.

2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

2023 HRS/APHRS/LAHRS guideline on cardiac physiologic pacing for the avoidance and mitigation of heart failure

Cardiac physiologic pacing (CPP), encompassing cardiac resynchronization therapy (CRT) and conduction system pacing (CSP), has emerged as a pacing therapy strategy that may mitigate or prevent the development of heart failure (HF) in patients with ventricular dyssynchrony or pacing-induced cardiomyopathy. This clinical practice guideline is intended to provide guidance on indications for CRT for HF therapy and CPP in patients with pacemaker indications or HF, patient selection, pre-procedure evaluation and preparation, implant procedure management, follow-up evaluation and optimization of CPP response, and use in pediatric populations. Gaps in knowledge, pointing to new directions for future research, are also identified.

Clinical, procedural and lead outcomes associated with different pacing techniques: a network meta-analysis

BACKGROUND

His- Purkinje system pacing (HPSP) techniques have been proposed as alternative to biventricular pacing (BVP) and right ventricular pacing (RVP).

OBJECTIVE

To compare data regarding clinical, procedural and lead outcomes associated with different pacing techniques.

METHODS

An accurate search of online scientific libraries (from inception to May, 12,022) was performed. Thirty-three studies were included in the meta-analysis involving 4386 patients, of whom 1324 receiving RVP, 1032 patients receiving BVP, 1069 patients receiving his-bundle pacing (HBP) and 968 patients receiving left bundle branch pacing (LBBP).

RESULTS

LBBP provided a statistically significant increase in LVEF relative to HBP (0.4473 [0.0584; 0.8361] p = 0.0242) and BVP (0.6733 [0.4734; 0.8732] p < 0.0001) in patients with cardiac resynchronization therapy indication. LBBP and HBP significantly decreased QRS duration as compared to BVP, with largest QRS narrowing obtained by LBBP (-0.4951 [-0.9077; -0.0824] p = 0.0187). As compared to LBBP, HBP was associated with a significant increase of pacing threshold (p = 0.0369) and significant reduction of R-wave amplitude over time (p = 0.027). LBBP was associated with significant reduction in RR of hospitalization for HF (HFH) as compared to both BVP (p = 0.0343) and HBP (p = 0.0476), whereas, as compared to RVP, the risk of lead issues was significantly higher with BVP (p = 0.0424) and HBP (p = 0.0298), but not for LBBP (p = 0.425).

CONCLUSIONS

As compared to other pacing techniques, LBBP significantly improved LVEF, narrowed QRS duration and reduced HFHs, with steadily lower capture thresholds and higher R-wave amplitude, and without increasing lead issues.

Meta-analysis of clinical outcomes in cardiac resynchronisation therapy: His Bundle Pacing vs biventricular pacing

INTRODUCTION AND OBJECTIVE

Cardiac resynchronization may treat severe heart failure (HF) with pharmacological optimization, left branch block, and an ejection fraction < 35%. However, 30-40% of patients fail therapy. HBP could replace biventricular pacing (BiV). We compared the effectiveness of HBP versus BiV in HF patients.

METHODS

We searched PubMed, Embase, and Cochrane for studies on QRS, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) functional class, left ventricular end-systolic volume (LVESV), and 6-minute walk test.

RESULTS

Six publications included 774 patients (mean [± standard deviation] age: 66.9 [14.0] years; 484 (62.5%) were males; 408 [52.71%] underwent HBP; the mean follow-up was 6-12 months. The HBP group had a higher QRS reduction in the meta-analysis (median: -17.54 [-20.46, -14.62]; I² = 89%). LVEF showed a median of 8.48 (7.55, 9.41) and I² of 98%, with a higher mean in HBP. The LVESV median was -18.89 (-30.03, -7.75) and I² was 0%, and the HBP group had a lower mean. HBP had a lower NYHA functional class (median= -0.20 [-0.28, -0.12]).

CONCLUSION

After implantation, HBP demonstrated bigger QRS shortening, increased LVEF, lower LVES volume, and lower NYHA class than BiV pacing.

Outcomes of conduction system pacing compared to right ventricular pacing as a primary strategy for treating bradyarrhythmia: systematic review and meta-analysis

BACKGROUND

Right ventricular pacing (RVP) may cause electrical and mechanical desynchrony leading to impaired left ventricular ejection fraction (LVEF). We investigated the outcomes of RVP with His bundle pacing (HBP) and left bundle branch pacing (LBBP) for patients requiring a de novo permanent pacemaker (PPM) for bradyarrhythmia.

METHODS AND RESULTS

Systematic review of randomized clinical trials and observational studies comparing HBP or LBP with RVP for de novo PPM implantation between 01 January 2013 and 17 November 2020 was performed. Random and fixed effects meta-analyses of the effect of pacing technology on outcomes were performed. Study outcomes included all-cause mortality, heart failure hospitalization (HFH), LVEF, QRS duration, lead revision, atrial fibrillation, procedure parameters, and pacing metrics. Overall, 9 studies were included (6 observational, 3 randomised). HBP compared with RVP was associated with decreased HFH (risk ratio [RR] 0.68, 95% confidence interval [CI] 0.49-0.94), preservation of LVEF (mean difference [MD] 0.81, 95% CI - 1.23 to 2.85 vs. - 5.72, 95% CI - 7.64 to -3.79), increased procedure duration (MD 15.17 min, 95% CI 11.30-19.04), and increased lead revisions (RR 5.83, 95% CI 2.17-15.70, p = 0.0005). LBBP compared with RVP was associated with shorter paced QRS durations (MD 5.6 ms, 95% CI - 6.4 to 17.6) vs. (51.0 ms, 95% CI 39.2-62.9) and increased procedure duration (MD 37.78 min, 95% CI 20.04-55.51).

CONCLUSION

Of the limited studies published, this meta-analysis found that HBP and LBBP were superior to RVP in maintaining physiological ventricular activation as an initial pacing strategy.

Generating Evidence to Support the Physiologic Promise of Conduction System Pacing: Status and Update on Conduction System Pacing Trials

Conduction system pacing avoids the potential deleterious effects of right ventricular pacing in patients with bradycardia and provides an alternative approach to cardiac resynchronization therapy. We focus on the available observational and randomized evidence and review studies supporting the safety, feasibility, and physiologic promise of conduction system approaches. We evaluate the randomized data generated from the available clinical trials of conduction system pacing, which have led to the recent inclusion of CSP in international guidelines. The scope for future randomized trials will building on the physiologic promise of conduction system approaches and offering information on clinical end points is explored.

Incidence and predictors of pacemaker-induced cardiomyopathy with right ventricular pacing: a systematic review

INTRODUCTION

This systematic review aims to evaluate the incidence and predictors of PICM in patients undergoing right ventricular pacing.

AREAS COVERED

A literature review was conducted using Mesh terms (Right ventricular pacing, Pacemaker-related cardiomyopathy, Pacemaker-induced cardiomyopathy) in PubMed, EMBASE, Web of science CINAHL, and the Cochrane Library until October 2021. All data reporting the incidence of PICM after implantation of right-sided pacemakers or implantable cardioverter-defibrillator (ICD) were retrieved from the eligible studies.

EXPERT OPINION

Out of 3,625 articles, 20 studies met the inclusion criteria that included 5,381 patients with PICM. The mean age of the patients ranged between 55.8 ± 13.5 and 77.4 ± 10.8 years. The mean incidence of PICM was 25.7%. Mean EF at baseline ranged from 48 ± 1% and 62.1 ± 11.2%, while mean EF at follow up ranged between 33.7± 7.4% and 53.2 ± 8.2%. Three studies reported a decline of >20% EF at follow-up. RV pacing was associated with a considerable risk of PICM, with biological factors such as male gender, old age, increased QRS duration, and chronic RV pacing burden playing an important role in the development of disease.

His Bundle Pacing – Stand-alone or adjunctive physiological pacing: a systematic review

His-bundle pacing (HBP) appears to be a viable stand-alone or adjunctive physiological pacing therapy in pacemaker dependent patients. It could also serve as an effective adjunct or alternative pacing therapy for heart failure patients who require cardiac resynchronization therapy or pacemaker upgrade. His-bundle pacing has demonstrated improvement of His-Purkinje conduction, left ventricular electrical / mechanical synchronization, and left ventricular ejection fraction (LVEF) compared with right ventricle pacing. Patients who have high pacing dependence and/or LVEF impairment would benefit most from HBP in terms of heart failure hospitalization and LVEF improvement. Mortality benefit has not been consistently demonstrated in latest meta-analysis. The long-term clinical benefit and safety profile of HBP remains to be explored in future studies.  Key words: His bundle pacing, physiologic pacing, upgrade pacing