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BACKGROUND In patients with or without left bundle branch block, left bundle branch pacing (LBBP) can produce near normalization of QRS duration (QRSd). This has recently emerged as an alternative technique to His bundle pacing.OBJECTIVES The purpose of this study was to characterize a novel approach for LBBP in patients with bradycardia indications for pacing and to assess implant success rate and midterm safety.METHODS Patients with bradycardia indications for pacing underwent LBBP by a trans-ventricular-septal method in the basal ventricular septum. Procedural success, pacing parameters, and complications were assessed at implantation and at 3 months follow-up.RESULTS This prospective study evaluated 87 patients (sinus node dysfunction 67.8%; atrioventricular conduction disease 32.2%) undergoing pacemaker implantation. LBBP implantation succeeded in 80.5% (70/87) of patients and the remaining 17 patients received right ventricular septal pacing. The procedure time of LBBP implantation was 18.0 6 8.8 minutes with a fluoroscopic exposure time of 3.9 6 2.7 minutes. LBBP produced narrower electrocardiographic QRSd than did right ventricular septal pacing (113.2 6 9.9 ms vs 144.4 6 12.8 ms; P , .001). There were no major implantationrelated complications. The pacing threshold was low (0.76 6 0.22 V at implantation and 0.71 6 0.23 V at 3 months), with no loss of capture or lead dislodgment observed.CONCLUSION This study demonstrates that in patients with standard bradycardia pacing indications, LBBP results in QRSd , 120 ms in most patients and can be performed successfully and safely in the majority of patients.

There is limited information about the structural property changes of soybean protein during fermentation. In this study, physicochemical analysis of soybean meal protein showed evidence that the increase in in vitro digestibility and absorbability of fermented soybean meal reflected the decrease in β-conformation and destruction of original structure in soybean meal protein. The results directly gained the understanding of nutritional quality improvement of soybean meal by Bacillus fermentation, and supply the potential use of Bacillus siamensis for fermented soybean meal production.

Introduction Left bundle branch pacing (LBBP) is characterized with a low and stable pacing capture threshold, relatively narrow QRS duration due to fast left ventricular activation, and direct excitation of the diseased left bundle branch. This report aims to describe the methods, procedural skills, and clinical implications of performing LBBP implantation. Methods and Results LBBP is achieved by transventricular‐septal approach. There are two methods to identify the location for LBBP lead placement: the single‐lead method and the dual‐lead method. During implantation, the unique transition of the paced QRS morphology and pacing parameter changes are important for guiding the lead ‐ advancement to the left side of the interventricular septum. In our experience, LBBP can be safely performed in most patients requiring pacemaker therapy. Conclusion Clinical development of LBBP is at an early but encouraging phase with increasing clinical use, and a standardized procedure with improved delivery tools and pacing leads is needed, as well as long‐term efficacy and safety.

Aims The present study was to evaluate the feasibility and clinical outcomes of left bundle branch area pacing (LBBAP) in cardiac resynchronization therapy (CRT)-indicated patients. Methods and results LBBAP was performed via transventricular septal approach in 25 patients as a rescue strategy in 5 patients with failed left ventricular (LV) lead placement and as a primary strategy in the remaining 20 patients. Pacing parameters, procedural characteristics, electrocardiographic, and echocardiographic data were assessed at implantation and follow-up. Of 25 enrolled CRT-indicated patients, 14 had left bundle branch block (LBBB, 56.0%), 3 right bundle branch block (RBBB, 12.0%), 4 intraventricular conduction delay (IVCD, 16.0%), and 4 ventricular pacing dependence (16.0%). The QRS duration (QRSd) was significantly shortened by LBBAP (intrinsic 163.6 ± 29.4 ms vs. LBBAP 123.0 ± 10.8 ms, P < 0.001). During the mean follow-up of 9.1 months, New York Heart Association functional class was improved to 1.4 ± 0.6 from baseline 2.6 ± 0.6 (P < 0.001), left ventricular ejection fraction (LVEF) increased to 46.9 ± 10.2% from baseline 35.2 ± 7.0% (P < 0.001), and LV end-diastolic dimensions (LVEDD) decreased to 56.8 ± 9.7 mm from baseline 64.1 ± 9.9 mm (P < 0.001). There was a significant improvement (34.1 ± 7.4% vs. 50.0 ± 12.2%, P < 0.001) in LVEF in patients with LBBB. Conclusion The present study demonstrates the clinical feasibility of LBBAP in CRT-indicated patients. Left bundle branch area pacing generated narrow QRSd and led to reversal remodelling of LV with improvement in cardiac function. LBBAP may be an alternative to CRT in patients with failure of LV lead placement and a first-line option in selected patients such as those with LBBB and heart failure.

Background - Left bundle branch pacing (LBBP) is a technique for conduction system pacing, but it often results in right bundle branch block (RBBB) morphology on the electrocardiogram. This study was designed to assess simultaneous pacing of the left and right bundle branch areas to achieve more synchronous ventricular activation. Methods - In symptomatic bradycardia patients, the distal electrode of a bipolar pacing lead was placed at the left bundle branch area via a trans-ventricular septal approach. This was used to pace the left bundle branch area, while the ring electrode was used to pace the right bundle branch area. Bilateral bundle branch area pacing (BBBP) was achieved by stimulating the cathode and anode in various pacing configurations. QRS duration, delayed right ventricular activation time (dRVAT), left ventricular activation time (LVAT) and inter-ventricular conduction delay were measured. Pacing stability and short-term safety were assessed at three-month follow-up. Results - BBBP was successfully performed in 22 of 36 patients. Compared with LBBP, BBBP resulted in greater shortening of QRS duration (109.3±7.1 ms vs. 118.4±5.7 ms, P<0.001). LBBP resulted in a paced RBBB configuration, with a dRVAT of 115.0±7.5 ms and inter-ventricular conduction delay of 34.0±8.8 ms. BBBP fully resolved the RBBB morphology in 18 patients. In the remaining 4 patients, BBBP partially corrected the RBBB with dRVAT decreasing from 120.5±4.7 ms during LBBP to 106.1±4.2 ms during BBBP (P=0.005). Conclusions - LBBP results in a relatively narrow QRS complex, but with an inter-ventricular activation delay. BBBP can diminish the delayed right ventricular activation, producing more physiological ventricular activation.

Flowering time and maturity are important agronomic traits for soybean cultivars to adapt to different latitudes and achieve maximal yield. Genetic studies on genes and quantitative trait loci (QTL) that control flowering time and maturity are extensive. In particular, the molecular bases of E1-E4, E6, E9, E10, and J have been deciphered. For a better understanding of regulation of flowering time gene networks, we need to understand if more molecular factors carrying different biological functions are also involved in the regulation of flowering time in soybeans. We developed a population derived from a cross between a landrace Jilincailihua (male) and a Chinese cultivar Chongnong16 (female). Both parents carry the same genotypes of E1e2E3HaE4 at E1, E2, E3, and E4 loci. Nighty-six individuals of the F2 population were genotyped with Illumina SoySNP8k iSelect BeadChip. A total of 2,407 polymorphic single nucleotide polymorphism (SNP) markers were used to construct a genetic linkage map. One major QTL, qFT12-1, was mapped to an approximately 567-kB region on chromosome 12. Genotyping and phenotyping of recombinant plant whose recombination events were occurring within the QTL region allowed us to narrow down the QTL region to 56.4 kB, in which four genes were annotated. Allelism and association analysis indicated Glyma.12G073900, a PRR7 homolog, is the strongest candidate gene for qFT12-1. The findings of this study disclosed the possible involvement of circadian clock gene in flowering time regulation of soybeans.

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