Comparison of cardiac function between left bundle branch pacing and right ventricular outflow tract septal pacing in the short-term: A registered controlled clinical trial

Safety and efficacy of left bundle branch area pacing compared with right ventricular pacing in patients with bradyarrhythmia and conduction system disorders: Systematic review and meta-analysis

BACKGROUND

Right Ventricular Pacing (RVP) may have detrimental effects in ventricular function. Left Bundle Branch Area Pacing (LBBAP) is a new pacing strategy that appears to have better results. The aim of this systematic review and meta-analysis is to compare the safety and efficacy of LBBAP vs RVP in patients with bradyarrhythmia and conduction system disorders.

METHODS

MEDLINE, EMBASE and Pubmed databases were searched for studies comparing LBBAP with RVP. Outcomes were all-cause mortality, atrial fibrillation (AF) occurrence, heart failure hospitalizations (HFH) and complications. QRS duration, mechanical synchrony and LVEF changes were also assessed. Pairwise meta-analysis was conducted using random and fixed effects models.

RESULTS

Twenty-five trials with 4250 patients (2127 LBBAP) were included in the analysis. LBBAP was associated with lower risk for HFH (RR:0.33, CI 95%:0.21 to 0.50; p < 0.001), all-cause mortality (RR:0.52 CI 95%:0.34 to 0.80; p = 0.003), and AF occurrence (RR:0.43 CI 95%:0.27 to 0.68; p < 0.001) than RVP. Lead related complications were not different between the two groups (p = 0.780). QRSd was shorter in the LBBAP group at follow-up (WMD: -32.20 msec, CI 95%: -40.70 to -23.71; p < 0.001) and LBBAP achieved better intraventricular mechanical synchrony than RVP (SMD: -1.77, CI 95%: -2.45 to -1.09; p < 0.001). LBBAP had similar pacing thresholds (p = 0.860) and higher R wave amplitudes (p = 0.009) than RVP.

CONCLUSIONS

LBBAP has better clinical outcomes, preserves ventricular electrical and mechanical synchrony and has excellent pacing parameters, with no difference in complications compared to RVP.

Safety and efficacy of His-Purkinje system pacing in the treatment of patients with atrial fibrillation and heart failure: a systematic review and meta-analysis

Aim

To evaluate the safety and efficacy of the His-Purkinje system pacing (HPCSP) in the treatment of individuals with atrial fibrillation (AF) complicated by heart failure (HF).

Methods

The PubMed, Cochrane Library, Web of Science, and Embase databases were searched through September 1, 2022. The literature was initially screened based on the inclusion and exclusion criteria. The baseline characteristics of the subjects, implantation success rate, New York Heart Association (NYHA) classification, left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDd), QRS duration, pacing threshold, and impedance were extracted and summarized; statistical analysis was performed using RevMan 5.3 software.

Results

In all, 22 articles were included, involving 1,445 patients. Compared to biventricular pacing (BiVP), HPCSP resulted in improved cardiac function, including increased ejection fraction (MD = 5.69, 95% CI: 0.78-10.60, P = 0.02) and decreased LVEDd (MD = -3.50, 95% CI: -7.05-0.05, P = 0.05). It was also correlated with shorter QRS duration (MD = -38.30, 95% CI: -60.71--15.88, P < 0.01) and reduced all-cause mortality and rehospitalization events (RR = 0.72, 95% CI: 0.57-0.91, P < 0.01) in patients. Left bundle branch pacing (LBBP) lowered the pacing threshold (MD = 0.47; 95% CI: 0.25-0.69; P < 0.01), and there was no statistical difference in the rate of endpoint events when comparing these two physiologic pacing modalities (RR = 1.56, 95% CI: 0.87-2.80, P = 0.14).

Conclusion

The safety and efficacy of HPCSP in patients with AF and HF were verified in this meta-analysis. HPCSP can reverse cardiac remodeling and has great clinical application value. Relatively speaking, His-bundle pacing (HBP) can maintain better ventricular electro-mechanical synchronization, and the pacing parameters of LBBP are more stable.

Systematic Review Registration

PROSPERO (CRD42022336109).

Echocardiographic Evaluation of the Effect on Left Ventricular Function Between Left Bundle Branch Pacing and Right Ventricular Pacing

Purpose

The purpose of this study was to assess the left ventricular function effects of permanent left bundle branch pacing (LBBP) versus traditional right ventricular pacing (RVP).

Patients and Methods

Consecutive patients receiving pacemaker implantation were included and divided into left bundle branch block (LBBB) group and right ventricular pacing (RVP) group. Baseline characteristics were collected, and they received 1-year follow-up. Electrocardiogram (ECG) characteristics and pacing parameters were assessed before and after implantation. Cardiac function parameters such as left ventricular ejection fraction (LVEF) and tricuspid regurgitation (TR) were recorded and compared.

Results

Of 78 patients included, 45 patients received LBBP (mean age, 72.7 ± 12.2 years; male, 55.6%) and 33 patients underwent RVP (mean age 72.9 ± 11.8 years; male, 63.6%). The pacing parameters were satisfactory during the implantation and remained stable during mid-term follow-up. During the follow-up period, LBBP patients had a greater decrease in LVEDD and LVESD. The TR in the LBBP group was significantly improved as compared to the RVP group (P=0.016).

Conclusion

Permanent LBBP achieves favorable cardiac hemodynamic effects with good stability and safety. LBBP may reduce severe TR at 1-year follow-up, and LBBP may be an option for patients with severe TR.

Long-term follow-up results of patients with left bundle branch pacing and exploration for potential factors affecting cardiac function

Background: Left bundle branch pacing (LBBP) is an alternative strategy for His bundle pacing (HBP). This study aimed to analyze the long-term performance of LBBP and the potential factors affecting long-term cardiac function.

Methods: Patients with LBBP were continuously enrolled from January 2018 to August 2020. Pacing parameters, electrocardiogram (ECG), and echocardiography were collected. The anatomic position of LBBP leads was described by echocardiographic and fluoroscopic parameters.

Results: A total of 91 patients with a median follow-up of 18 months were enrolled. Most patients maintained stable pacing parameters during follow-up. The intra-septal position of the 3830 lead also remained stable as the distance from the lead tip to the left surface of the ventricular septum was 0.4 (0, 1.4) mm. The overall level of left ventricular ejection fraction (LVEF) slightly increased. 59 patients had improved LVEF (∆LVEF &gt; 0), while 28 patients had unchanged or reduced LVEF (∆LVEF ≤ 0). The declines of baseline LVEF, ∆ Paced QRSd, and corrected longitudinal distance (longit-dist) of lead-implanted site correlated with LVEF improvement, and these three factors had negative linear correlations with ∆LVEF. Patients with tricuspid valve regurgitation (TVR) deterioration had longer follow-up duration (20.5 vs. 15.0 months, p = 0.01) and shorter Lead-TVA-dist (18.6 vs. 21.6 mm, p = 0.04) than those without TVR deterioration.

Conclusion: Patients with LBBP generally remained stable in pacing performance, anatomic lead positions, and cardiac function in long-term follow-up. Baseline LVEF, ∆ Paced QRSd, and corrected longit-dist might be associated with potential LVEF decrease, which required further confirmation.

The effect of different preoperative left atrial appendage emptying speeds on left atrial function in patients with persistent atrial fibrillation after left atrial appendage closure combined with catheter ablation

Objective

The present study aimed to investigate whether different preoperative left atrial appendage emptying speeds (LAAEVs) have an effect on left atrial function in patients with sinus arrhythmia after left atrial appendage closure (LAAC) combined with catheter ablation (CA).

Methods

A total of 163 patients with persistent non-valvular atrial fibrillation who received combined LAAC+CA surgery were included in the present study. Regular follow-up was conducted for 12 months, and patients with complete data and successful sinus rhythm recovery were selected as the study subjects (n = 82). The patients were divided into two groups: the LAAEV < 25 cm/s group and the LAAEV ≥ 25 cm/s group (n = 41 each). The propensity score was used for matching according to gender, age, CHA₂DS₂-VASc score, and HAS-BLED score. The changes in the two groups in LA structure, storage function, conduit function, and pump function were compared.

Results

Before surgery, the maximum LA volume (LAV_max) and minimum LA volume (LAV_min) were greater in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. The LA storage function (eg. Ƹ and SRs), conduit function (eg. SRe), and pump function (eg. SRa) were all worse in the LAAEV < 25 cm/s group than in the LAAEV ≥ 25 cm/s group. After the combined LAAC+CA surgery, the LA storage, conduit, and pump functions improved in both groups. At 12 months after surgery, there were no statistically significant differences between the two groups.

Conclusion

Before combined LAAC+CA surgery, the LA structure and function of the LAAEV < 25 cm/s group were worse than those of the LAAEV ≥ 25 cm/s group. However, after LAAC+CA surgery, the LA structure and function of the patients were improved, and there were no significant differences between the two groups. Inferred improvement in LA structure and function in the LAAEV < 25 cm/s group was superior to that in the LAAEV ≥ 25 cm/s group.

New-onset atrial fibrillation following left bundle branch area pacing vs. right ventricular pacing: a two-centre prospective cohort study

AIMS

To investigate whether left bundle branch area pacing (LBBAP) can reduce the risk of new-onset atrial fibrillation (AF) compared with right ventricular pacing (RVP).

METHODS AND RESULTS

Patients with indications for dual-chamber pacemaker implant and no history of AF were prospectively enrolled if they underwent successful LBBAP or RVP. The primary endpoint was time to the first occurrence of AF detected by pacemaker programming or surface electrocardiogram. Follow-up at clinic visit was performed and multivariate Cox regression models were applied to evaluate the effect of LBBAP on new-onset AF. The final analysis included 527 patients (mean age 65.3 ± 12.6, male 47.3%), with 257 in the LBBAP and 270 in the RVP groups. During a mean follow-up of 11.1 months, LBBAP resulted in significantly lower incidence of new-onset AF (7.4 vs. 17.0%, P < 0.001) and AF burden (3.7 ± 1.9 vs. 9.3 ± 2.2%, P < 0.001) than RVP. After adjusting for confounding factors, LBBAP demonstrated a lower hazard ratio for new-onset AF compared with RVP {hazard ratio (HR) [95% confidence interval (CI)]: 0.278 (0.156, 0.496), P < 0.001}. A significant interaction existed between pacing modalities and the percentage of ventricular pacing (VP%) (P for interaction = 0.020). In patients with VP ≥ 20%, LBBAP was associated with decreased risk of new-onset AF compared with RVP [HR (95% CI): 0.199 (0.105, 0.378), P < 0.001]. The effect of pacing modalities was not pronounced in patients with VP < 20% [HR (95% CI): 0.751 (0.309, 1.823), P = 0.316].

CONCLUSION

Left bundle branch area pacing demonstrated a reduced risk of new-onset AF compared with RVP. Patients with a high ventricular pacing burden might benefit from LBBAP.

Left bundle branch pacing in a ventricular pacing dependent patient with heart failure: A case report

BACKGROUND

Left bundle branch pacing (LBBP) is a physiological pacing method that has emerged in recent years. It is an ideal choice for patients with complete left bundle branch block who are in need of cardiac resynchronization therapy (CRT). Moreover, LBBP is superior in maintaining physiological ventricular activation and can effectively improve heart function and quality of life in patients with pacemaker-induced cardiomyopathy. However, LBBP in pacing-dependent patients who already have cardiac dysfunction has not been well assessed.

CASE SUMMARY

A 69-year-old male patient presented with symptoms of chest tightness, palpitation and systolic heart failure with New York Heart Association class III for 1 mo. The 12-lead electrocardiogram showed atrial fibrillation with third-degree atrioventricular block and ventricular premature beat. Holter revealed a right bundle branch block, atrial fibrillation with third-degree atrioventricular block, frequent multifocal ventricular premature beats, Ron-T and ventricular tachycardia. The echocardiogram documented an enlarged left atrium and left ventricle and a low left ventricular ejection fraction. Coronary angiography indicated a stenosis of 30% in the middle left anterior descending artery. Apparently, a CRT-D pacemaker was the best choice for this patient according to previous findings. However, the patient was worried about the financial burden. A single-chamber pacemaker with LBBP was selected, with the plan to take amiodarone and upgrade with dual-chamber implantable cardioverter-defibrillator or CRT-D at an appropriate time. During the follow-up at 3 mo after LBBP, the patient showed an improvement in cardiac function with slight improvement in echocardiography parameters, and the New York Heart Association functional class was maintained at I. Moreover, the patient no longer suffered from chest tightness and palpitation. Holter showed decreased ventricular arrhythmia of less than 5%.

CONCLUSION

LBBP might be used in patients with heart failure and a high-degree atrioventricular block as an alternative to conventional CRT.

Effect of radiofrequency catheter ablation on left atrial structure and function in patients with different types of atrial fibrillation

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF), but its effect on left atrial (LA) remodeling in patients with AF is not completely clarified. Few studies have reported the changes in structure and function of the left atrium in patients with different types of AF after RFCA. To analyze the effect of RFCA on the LA structure and function in patients with nonvalvular paroxysmal AF, persistent AF and long-standing persistent AF (LSPAF). RFCA was performed in 180 patients with paroxysmal AF, persistent AF and LSPAF. The changes of LA structure and function in echocardiogram and speckle-tracking echocardiography findings were compared before the procedure, and at 1, 2, 3, 4 weeks, and 2, 3, 6, and 9–12 months after the procedure. There were 60 patients in the paroxysmal AF group, 60 in the persistent AF group and 60 patients in LSPAF group. The pre-procedure LA diameter and volume were smaller in the paroxysmal AF group than persistent AF and LSPAF group. There was no significant change of in the LA structure and function in the paroxysmal AF group within 1 year. In the persistent AF and LSPAF groups, LA structure (anteroposterior diameter, LA volume) significantly decreased, but remained larger than that in paroxysmal AF group. In persistent and LSPAF, function (LA ejection fraction, strain, strain rate) increased significantly within 1 week, then gradually increased. RFCA improved the LA structure and function and resulted in heart reverse remodeling, especially for persistent AF and LSPAF.

Physiology of Left Ventricular Septal Pacing and Left Bundle Branch Pacing

Following the recognition of the adverse effects of right ventricular pacing, alternative permanent pacing strategies aiming to maintain a synchronous ventricular contraction have been sought. The quest for the optimal pacing site has recently led to several promising and rapidly emerging new pacing strategies, such as left ventricular septal pacing and left bundle branch pacing. In both animal and human studies, these pacing strategies seem to maintain electrical and mechanical activation of the left ventricle to a (near)physiologic level. However, more studies on the long-term effects of both strategies are needed.

Molecular Mechanism of Induction of Bone Growth by the C-Type Natriuretic Peptide

The skeletal development process in the body occurs through sequential cellular and molecular processes called endochondral ossification. Endochondral ossification occurs in the growth plate where chondrocytes differentiate from resting, proliferative, hypertrophic to calcified zones. Natriuretic peptides (NPTs) are peptide hormones with multiple functions, including regulation of blood pressure, water-mineral balance, and many metabolic processes. NPTs secreted from the heart activate different tissues and organs, working in a paracrine or autocrine manner. One of the natriuretic peptides, C-type natriuretic peptide-, induces bone growth through several mechanisms. This review will summarize the knowledge, including the newest discoveries, of the mechanism of CNP activation in bone growth.

Impact of Left Atrial Appendage Closure Combined with Catheter Ablation on Endocrine and Mechanical Cardiac Function in Patients with Atrial Fibrillation

Background

The combined procedure of left atrial appendage closure (LAAC) and catheter ablation (CA) is a safe and feasible therapy to treat patients with atrial fibrillation (AF). However, the effect of the combined procedure on cardiac function remains unclear. This study aimed to investigate the changes in endocrine and mechanical function of the heart following the combined procedure.

Methods

This retrospective study included 62 consecutive patients who underwent the combined procedure of AF ablation and WATCHMAN LAAC and 62 sex and age-matched patients who only received AF ablation. During follow-up, patients were examined for brain natriuretic peptide (BNP) levels to represent endocrine cardiac function. Mechanical cardiac function was assessed during echocardiographic examination by means of the LA ejection fraction, LA strain (Ƹ), and LA strain rate (SR).

Results

(1) The BNP levels decreased acutely after the procedure, rose at day 3 postoperation, but trended downwards at 3 months postoperation in both groups. No significant difference was observed between the two groups. (2) LA ejection fraction, LA Ƹ, and SR exhibited a continuous upward trend over a 3-month follow-up in both groups. There was no significant difference in LA ejection fractions, SRe (the parameter of LA conduit function), and SRa (the parameter of LA booster pump function) between the two groups. However, the Ƹ and SRs (the parameters of LA reservoir function) improved in patients treated with CA alone.

Conclusions

The combined procedure of LAAC and CA significantly improved the endocrine and mechanical function of the heart. Compared to simple CA, based on CA with LAAC intervention, it does not significantly change LA endocrine function but may lead to a decline in the LA reservoir function.

Clinical impact of left bundle branch area pacing in heart failure with preserved ejection fraction and mid-range ejection fraction

BACKGROUND

Recently, conduction system pacing, including His bundle and left bundle branch area pacing (LBBAP), has emerged as an alternative pacing procedure for right ventricular (RV) pacing. The current study aimed to compare the clinical outcomes of LBBAP and conventional RV mid-septal pacing (RVMSP) in patients with heart failure (HF) with preserved ejection fraction (HFpEF) and HF with mid-range ejection (HFmrEF) requiring frequency RV pacing due to atrioventricular block (AVB).

METHODS

A total of 89 patients with HFpEF and HFmrEF requiring RV pacing due to symptomatic AVB were enrolled between September 2018 and April 2021, among whom 43 and 46 underwent LBBAP and RVMSP, respectively.

RESULTS

No significant differences in baseline characteristics were observed between the two groups. The LBBAP group had a significantly shorter paced-QRS duration and paced left ventricular activation time (LVAT) compared to the RVMSP group (123.4 ± 10.4 ms vs. 152.3 ± 12.3 ms, p < 0.001 and 68.3 ± 10.0 ms vs. 95.2 ± 12.3 ms, p < 0.001, respectively). The LBBAP group had significantly lower N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels at the 6-month follow-up compared to the RVMSP group [459.6 pg/mL (240.4-678.7) vs. 972.7 pg/mL (629.5-1315.9), p = 0.01]. More patients in the LBBAP group exhibited a significant improvement in NT-proBNP, defined as a >50% decreased from baseline levels.

CONCLUSION

LBBAP maintains physiological ventricular activation and contributes to greater improvement in NT-proBNP value 6 months after implantation in patients with HFpEF and HFmrEF compared to RVMSP. This article is protected by copyright. All rights reserved.

Medium- and Long-Term Lead Stability and Echocardiographic Outcomes of Left Bundle Branch Area Pacing Compared to Right Ventricular Pacing

The long-term lead stability and echocardiographic outcomes of left bundle branch area pacing (LBBAP) are not fully understood. This study aimed to observe the mid-long-term clinical impact of LBBAP compared to right ventricular pacing (RVP). Consecutive bradycardia patients undergoing LBBAP or RVP were enrolled. Pacing and electrophysiological characteristics, echocardiographic measurements, and procedural complications were prospectively recorded at baseline and follow-up. LBBAP was successful in 376 of 406 patients (92.6%), while 313 patients received RVP. During a mean follow-up of 13.6 ± 7.8 months, LBBAP presented with similar pacing parameters and complications to RVP, except a significantly narrower paced QRS duration (115.7 ± 12.3 ms vs. 148.0 ± 18.0 ms, p < 0.001). In 228 patients with ventricular pacing burden >40%, LBBAP at last follow-up resulted in decreased left atrial diameter (LAD) (40.1 ± 8.5 mm vs. 38.5 ± 8.0 mm, p < 0.001) while RVP produced decreased left ventricular ejection fraction (62.7 ± 4.8% vs. 60.5 ± 6.9%, p < 0.001) when compared to baseline. After adjusting for age, the presence of atrial fibrillation, and other clinical factors, LBBAP was still associated with a decrease in LAD (-1.601, 95% CI -3.094--0.109, p = 0.036). We conclude that LBBAP might result in more preserved echocardiographic outcomes than RVP.

Left bundle branch area pacing versus right ventricular pacing in patients with persistent atrial fibrillation requiring ventricular pacing

PURPOSE

This study aims to assess whether left bundle branch area pacing (LBBAP) can result in favorable clinical and echocardiographic outcomes among patients with persistent atrial fibrillation (PeAF).

METHODS

We prospectively enrolled consecutive patients with PeAF if they required ventricular pacing and had left ventricular ejection fraction (LVEF) > 35%. During the same period, two experienced operators performed LBBAP and right ventricular pacing (RVP). All-cause death and heart failure hospitalization (HFH) were routinely followed after procedure. The primary outcome was the composite endpoints of all-cause death or HFH.

RESULTS

LBBAP was successful in 49 of 52 patients (94.2%), whereas 44 patients received RVP. During a mean follow-up of 13.9 ± 7.0 months, LBBAP group presented with higher ventricular pacing percentage (80% vs. 50.9%, p = .04) and narrower paced QRS duration (117.2 ± 18.8 ms vs. 151.8 ± 13.7 ms, p < .001) than RVP group. The primary endpoint was slightly reduced in LBBAP group than RVP without reaching statistical significance (7.7% vs. 11.4%, p = .48). Compared with baseline, we observed significant changes in LVEF (+0.7% vs. -2.2%, p = .007) and left atrial diameter (-1.63 mm vs. +1.23 mm, p = .011) between LBBAP and RVP.

CONCLUSION

Our results indicate possible effect of LBBAP on reverse remodeling of left atrium and a trend towards favorable clinical outcomes in patients with PeAF requiring high burden of ventricular pacing when compared with RVP.

His-Purkinje conduction system pacing: A systematic review and network meta-analysis in bradycardia and conduction disorders

BACKGROUND

His-Purkinje conduction system pacing (HPCSP) has emerged as an effective alternative to overcome the limitations of right ventricular pacing (RVP) via physiological left ventricular activation, but there remains a paucity of comparative information for His bundle pacing (HBP) and left bundle branch pacing (LBBP).

METHODS

A Bayesian random-effects network analysis was conducted to compare the relative effects of HBP, LBBP, and RVP in patients with bradycardia and conduction disorders. PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from database inception until September 21, 2021.

RESULTS

Twenty-eight studies involving 4160 patients were included in this meta-analysis. LBBP significantly improved success rate, pacing threshold, pacing impedance, and R-wave amplitude compared with HBP. LBBP also demonstrated a nonsignificant trend towards superior outcomes of lead complications, heart failure hospitalization, atrial fibrillation, and all-cause death. However, HBP was associated with significantly shorter paced QRS duration relative to LBBP. Despite higher success rates, shorter procedure/fluoroscopy duration, and fewer lead complications, patients receiving RVP were more likely to experience reduced left ventricular ejection fraction, longer paced QRS duration, and higher rates of heart failure hospitalization than those receiving HPCSP. No statistical differences were observed in the remaining outcome measures.

CONCLUSIONS

This network meta-analysis demonstrates the efficacy and safety of HPCSP for the treatment of bradycardia and conduction disorders, with differences in pacing parameters, electrophysiology characteristics, and clinical outcomes between HBP and LBBP. Larger-scale, long-term comparative studies are warranted for further verification.

Safety and efficacy of left bundle branch pacing in comparison with conventional right ventricular pacing: A systematic review and meta-analysis

BACKGROUND

Right ventricular pacing (RVP) has been widely accepted as a traditional pacing strategy, but long-term RVP has detrimental impact on ventricular synchrony. However, left bundle branch pacing (LBBP) that evolved from His-bundle pacing could maintain ventricular synchrony and overcome its clinical deficiencies such as difficulty of lead implantation, His bundle damage, and high and unstable thresholds. This analysis aimed to appraise the clinical safety and efficacy of LBBP.

METHODS

The Medline, PubMed, Embase, and the Cochrane Library databases from inception to November 2020 were searched for studies comparing LBBP and RVP.

RESULTS

Seven trials with 451 patients (221 patients underwent LBBP and 230 patients underwent RVP) were included in the analysis. Pooled analyses verified that the paced QRS duration (QRSd) and left ventricular mechanical synchronization parameters of the LBBP capture were similar with the native-conduction mode (P > .7),but LBBP showed shorter QRS duration (weighted mean difference [WMD]: -33.32; 95% confidence interval [CI], -40.44 to -26.19, P < .001), better left ventricular mechanical synchrony (standard mean differences: -1.5; 95% CI: -1.85 to -1.14, P < .001) compared with RVP. No significant differences in Pacing threshold (WMD: 0.01; 95% CI: -0.08 to 0.09, P < .001), R wave amplitude (WMD: 0.04; 95% CI: -1.12 to 1.19, P = .95) were noted between LBBP and RVP. Ventricular impedance of LBBP was higher than that of RVP originally (WMD: 19.34; 95% CI: 3.13-35.56, P = .02), and there was no difference between the 2 groups after follow-up (WMD: 11.78; 95% CI: -24.48 to 48.04, P = .52). And follow-up pacing threshold of LBBP kept stability (WMD: 0.08; 95% CI: -0.09 to 0.25, P = .36). However, no statistical difference existed in ejection fraction between the 2 groups (WMD: 1.41; 95% CI: -1.72 to 4.54, P = .38).

CONCLUSIONS

The safety and efficacy of LBBP was firstly verified by meta-analysis to date. LBBP markedly preserve ventricular electrical and mechanical synchrony compared with RVP. Meanwhile, LBBP had stable and excellent pacing parameters. However, LBBP could not be significant difference in ejection fraction between RVP during short- term follow-up.

Effect of Left Atrial Appendage Closure in Combination With Catheter Ablation on Left Atrial Function for Persistent Atrial Fibrillation

Background: A single procedure combining left atrial appendage closure (LAAC) plus catheter ablation (CA) has been proven to be safe and feasible for treating atrial fibrillation (AF). However, the influence of treatment modality on left atrial (LA) function is not thoroughly explained.

Objective: We aimed to investigate the changes of LA function in persistent AF patients undergoing concomitant LAAC and CA.

Methods: The study population comprised 65 patients who underwent combined AF ablation and Watchman LAAC (combined therapy group) in our center, and 65 participants of the AF simple ablation group who were matched based on sex, age, CHA₂DS₂-VASc score and HAS-BLED score using propensity score matching. During the 1-year follow-up period, two-dimensional echocardiography and speckle tracking echocardiography were performed to assess LA reservoir, conduit, and contractile function.

Results: The combined therapy was associated with a significant improvement in the LA reservoir function with increased expansion index and strain indices, including strain and strain rate (SR) during ventricular systole. Conduit function with SR during early ventricular diastole was also improved, as was contractile function with active atrial emptying fraction and SR during atrial systole. Similarly, LA reservoir and contractile function indices all improved continuously during follow-up after catheter ablation alone. At 3 months follow-up LA reservoir and conduit function with strain indices had a tendency to improve only in the simple procedure group. At 1-year follow-up there was no significant difference in either LA volumes or strain indices between the two groups.

Conclusion: Both the combined therapy group and the simple ablation group demonstrated significant improvement in LA function. Based upon the fact that LA function was improved in both groups it might be concluded that most of the effects appeared to result from ablation, not LAAC; furthermore the additional LAAC procedure did not affect the improvement of LA function after CA.

Efficacy of upgrading to left bundle branch pacing in patients with heart failure after right ventricular pacing

BACKGROUND

Chronic right ventricular (RV) pacing is associated with an increased incidence of heart failure and mortality. Left bundle branch (LBB) pacing could produce near-physiological electrical activation and mechanical synchrony. We aimed to report the effects of upgrading to LBB pacing in heart failure patients after chronic RV pacing.

METHODS

The indications included pacing-induced cardiomyopathy (PICM) in Group 1 and heart failure after RV pacing with left ventricular ejection fraction (LVEF) ≥ 50% in Group 2. LBB pacing was achieved by penetrating the pacing lead to the subendocardium of left-sided interventricular septum through the venous access. Left ventricular activation time (LVAT) was measured from the pacing stimulus to the ascending peak of lead V5 or V6. All patients underwent clinical and echocardiographic evaluations before and after upgrading.

RESULTS

Totally 27 patients (13 in Group 1 and 14 in Group 2) were consecutively enrolled. The mean follow-up time after upgrade was 10.4 ± 6.1 months. Paced QRS duration was significantly shortened from 174.1 ± 15.8 milliseconds to 116.6 ± 11.7 milliseconds (p < .0001). The mean LVAT was 83.2 ± 11.7 milliseconds. LVEF increased from 40.3 ± 5.2% before upgrading to 48.1 ± 9.5% at follow-up in patients with PICM. Serum N-terminal probrain natriuretic peptide levels decreased and New York Heart Association classification improved in both groups. No upgrade-related complications were observed.

CONCLUSIONS

Upgrading to LBB pacing was feasible and effective with improved cardiac function in heart failure patients with both reduced and preserved LVEF after RV pacing.