Research Progress in the Effect of His-Purkinje Conduction System Pacing on Cardiac Function / 中山大学学报(医学科学版)

Cardiac pacing is an effective treatment for cardiac pacing and conduction dysfunction and severe heart failure. However， the conventional right ventricular pacing may increase the incidences of heart failure and atrial fibrillation， and biventricular pacing has a relatively high non-response rate. As a new technique of physiological pacing， a number of studies in recent years have been conducted to show the stability of pacing parameters and good cardiac synchronization of his-purkinje system pacing. This article reviews the current status of research and progress in the effects of his-purkinje conduction system pacing on cardiac function， so as to provide a theoretical basis for promoting the development of this technology.

Mejoría clínica, hemodinámica y de marcadores bioquímicos tras estimulación ventricular desde el área de la rama izquierda / Clinical, hemodynamic and biochemical improvement related to left bundle branch area pacing

Resumen Introducción: La estimulación ventricular derecha puede provocar insuficiencia cardiaca y disfunción ventricular. La estimulación en el área de la rama izquierda (ERI) permite capturar el sistema His-Purkinje. La ERI se ha estudiado en la estimulación ventricular y en la terapia de resincronización cardiaca. La evolución de los péptidos natriuréticos (NT-proBNP) asociada a la ERI no ha sido estudiada hasta el momento. Métodos: Se incluyeron pacientes consecutivos remitidos para implante de marcapasos o terapia de resincronización cardiaca. El implante del electrodo de ERI se realizó siguiendo la técnica descrita por Huang et al. Los pacientes eran sometidos a ecocardiograma y determinación de NT-proBNP antes y cuatro semanas después del procedimiento. Resultados: Se analizaron 50 pacientes con implante exitoso y seguimiento completo. No hubo diferencias significativas entre los umbrales medidos durante el procedimiento y los obtenidos al cabo de 12 semanas. La ERI logró una reducción significativa de la anchura del complejo QRS (148 ± 21 vs. 107 ± 11 ms; p = 0.029). La ERI logró una reducción significativa de la clasificación funcional en el conjunto de la muestra y una reducción significativa de NT-proBNP (2,888.2 ± 510 vs. 1,181 ± 130 pg/ml; p = 0.04). En pacientes con fracción de eyección del ventrículo izquierdo (FEVI) < 50% y asincronía se logró un incremento significativo de la FEVI con la ERI (40.2 ± 7 vs. 55.2 ± 7%; p < 0.001). Conclusiones: La ERI es factible en la mayoría de pacientes y se asocia con una reducción de la duración del complejo QRS. La ERI no condiciona un efecto deletéreo sobre la FEVI a corto-medio plazo; además, en aquellos pacientes con FEVI deprimida y asincronía ventricular permite incrementar la FEVI.

Abstract Background: Right ventricular pacing is associated with risk of heart failure and left ventricular dysfunction. Left bundle branch area pacing (LBBP) has emerged as an alternative method for delivering physiological pacing. The effect of LBBP on N-terminal pro-brain natriuretic peptide (NT-proBNP) has not been investigated. Method: Finally, 50 patients referred for pacemaker implantation were included. LBBP was performed as described previously by Huang et al. Transthoracic echocardiogram and NT-proBNP were performed before and four weeks after the procedure. Results: 50 patients were analyzed. There were not differences between ventricular thresholds during the procedure and 3 months later, LBBP significantly reduced QRS complex duration (148 ± 21 vs. 107 ± 11 ms; p = 0.029). LBBP significantly improved NYHA functional class and reduced NT-proBNP concentration (2888.2 ± 510 vs. 1181 ± 130 pg/ml; p = 0.04). In patients showing left ventricular ejection fraction (LVEF) < 50% and ventricular desynchrony LBBP showed a significant LVEF increase (40.2 ± 7 vs. 55.2 ± 7%; p < 0.001). Conclusions: LBBP was feasible and safe in most of patients. LBBP was associated with reduction in QRS width and with increase in LVEF in patients with ventricular desynchrony, while in patients with normal LVEF it remained unchanged during follow-up.

Application of the LBBP in patients with bradyarrhythmia:Meta-analysis / 中国医学装备

Objective:To compare the effects of left bundle branch pacing(LBBP)and right ventricular pacing(RVP)on pacing threshold value,pacing perception,pacing impedance,QRS wave complex duration,interventricular mechanical delay(IVMD)time,left ventricular end diastolic diameter(LVEDD)and left ventricular ejection fraction(LVEF).Methods:The Chinese databases included China Biology Medicine Disc(CBMdisc),China National Knowledge Infrastructure(CNKI),Wanfang Database,China Science and Technology Journal Database,and foreign databases included PubMed,Cochrane library and Embase were adopted to retrieve research literatures about LBBP.The retrieval duration was from January 2018 to November 2021.The literatures were screened according to the inclusion and exclusion criteria of literatures,and the qualities of the literatures that met the inclusion criteria were respectively evaluated.The extracted relevant data of LBBP and RVP,which included pacing threshold value,pacing perception,pacing impedance,QRS wave complex duration,IVMD time,LVEDD and LVEF,were adopted to conduct Meta-analysis by using Revman5.4.Results:A total of 14 relevant literatures were included according to the inclusion and exclusion criteria of research literatures,which included 9 Chinese literatures and 5 English literatures.The duration of publication times of these literature was from 2018 to 2021.In these literatures,640 patients involved to LBBP and 551 patients involved to RVP.There were no significant differences between LBBP and RVP in the effects on pacing threshold value,pacing perception and pacing impedance[95%CI(-0.05-0.02),(-0.28-0.42),(-22.34-16.19),P>0.05],respectively.There were significant differences between LBBP and RVP in the effects on QRS wave complex duration,IVMD and LVEF[95%CI(-45.92--42.09),(-16.49--10.86),(3.01-5.13),P<0.05],respectively.There were two different results in the effects of LBBP and RVP on LVEDD.The five literatures among of them conducted effect size merging for the extracted LVEDD values.There was significant difference between two kinds of pacing methods in the effect on LVEDD[95%CI(-2.21--0.54),P<0.05].There was significant difference between two kinds of pacing methods in the effect on LVEDD after the literature(ShigengZhang2020)was excluded.Conclusion:The Meta-analysis about the application of LBBP in patients with bradyarrhythmia has demonstrated the effectiveness of LBBP.Compared with RVP,LBBP is more close to physiological pacing,and LBBP pacing parameters(threshold value,perception and impedance)are stable.

Pressure-strain loops technique detects the effects of different pacing modes of left bundle branch on left ventricular myocardial work / 中华超声影像学杂志

Objective:To evaluate the effects of different pacing modes (unipolar/bipolar) under left bundle branch pacing(LBBP) on ventricular mechanical synchrony and myocardial work using the pressure-strain loop technique.Methods:Twenty-nine patients with LBBP due to symptomatic bradycardia were collected as LBBP group in Sun Yat-sen Memorial Hospital of Sun Yat-sen University from December 2018 to July 2020. Another 29 matched patients with right ventricular pacing (RVP) during the same period were also included as a RVP group. Each LBBP patient was programmed to different pacing modes (uni-/bio-polar) within 1 week after the operation.Under each pacing mode, the inter- and intra-ventricular mechanical synchronization were evaluated. Meanwhile, the global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were obtained by the left ventricular pressure-strain loops technique.Results:Compared with the RVP group, the mechanical synchrony in the LBBP group was significantly improved (all P<0.05). GWI, GCW, and GWE increased, while GWW decreased, and the differences were statistically significant (all P<0.05), there were no significant differences in ventricular mechanical synchronization, GWI, GCW, GWE, and GWW between unipolar and bipolar pacing in the LBBP group (all P>0.05), there were no significant differences in these parameters when increasing output voltage (all P>0.05). Conclusions:LBBP induces better mechanical synchronization and higher myocardial work efficiency than RVP. Different LBBP pacing modes do not affect ventricular mechanical synchronization and myocardial work efficiency.

Left ventricular systolic function between left bundle branch pacing and right ventricular septum pacing in patients with pacemaker dependence by three-dimensional speckle tracking imaging / 中南大学学报(医学版)

OBJECTIVES@#To compare the left ventricular systolic function between the 1eft bundle branch pacing (LBBP) and right ventricular septum pacing (RVSP) in patients with pacemaker dependence by three-dimensional speckle tracking imaging (3D-STI).@*METHODS@#A total of 65 patients with atrioventricular block (AVB) (Mobitz type II second-degree AVB, high-degree AVB, or third-degree AVB), who underwent permanent cardiac pacing implantation including 32 patients receiving LBBP (LBBP group) and 33 patients receiving RVSP (RVSP group) from June 2018 to June 2019,were enrolled in this study. These patients met the following inclusion criterion: pre-operative left ventricular ejection fraction (LVEF)>50% and ventricular pacing rate>40% at 6-month programming follow-up; and the patients underwent echocardiography at pre-operation and 6 months after operation. The 3D-STI was used to obtain global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and global area strain (GAS).@*RESULTS@#All the patients in the LBBP group and the RVSP group had normal LVEF, there was no significant difference between the 2 group (@*CONCLUSIONS@#For patients with pacemaker dependence and normal LVEF at pre-operation, the cardiac function in the LBBP group is not significantly better than that in the RVSP group in short term follow-up. But in terms of physiologic pacing and long-term cardiac function protection, the 1eft bundle branch pacing is an optimal pacing mode.