Efficacy of Closed Loop Stimulation in Left Bundle Branch Area Pacing

Efficacy of Closed Loop Stimulation in Left Bundle Branch Area Pacing | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Efficacy of Closed Loop Stimulation in Left Bundle Branch Area Pacing Hirad Yarmohammadi, Bobak Salehi, Margaret Shea, Camden Harrell, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8897052/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Closed-Loop Stimulation (CLS) adjusts pacing rate based on beat-to-beat impedance changes reflecting myocardial contractility and autonomic tone. While early studies focused on right ventricular apical leads, conduction system pacing, particularly left bundle branch area pacing (LBBAP) offers a more physiologic approach. The effect of septal lead position on CLS performance remains unclear. Objective: To investigate the impact of LBBAP versus alternative right ventricular lead positions on CLS performance. Methods: We conducted a retrospective cohort study using the CERTITUDE registry, which includes longitudinal remote monitoring data from over 55,000 U.S. patients with Biotronik devices. Patients with dual-chamber pacemakers implanted after January 1, 2021, with ≥6 months of follow-up were included, excluding those with ≥20% atrial fibrillation burden or <50% transmission rate. Pacing characteristics were compared across DDD and DDD-CLS modes and between LBBAP and non-LBBAP lead locations . Results: A total of 5,395 patients were included. Baseline mean thoracic impedance was higher in non-LBBAP groups (P<0.001), though changes over time were not significant (P=0.336). Mean ventricular rate increased in the non-LBBAP DDD-CLS group but decreased in the DDD group (P<0.001). Atrial arrhythmia burden was similar across pacing modes and lead locations, except for a higher burden in the non-LBBAP DDD-CLS group compared with non-LBBAP DDD. Conclusions: In this large real-world cohort, CLS maintained stable physiological rate adaptation across pacing modes and lead locations. Minor differences in ventricular rate and thoracic impedance were observed, but overall CLS performance was consistent between LBBAP and non-LBBAP configurations, supporting its use in conduction system pacing. Closed loop stimulation left bundle branch area pacing rate-adaptation pacemaker Introduction Closed Loop Stimulation (CLS) algorithm is designed to regulate paced rate-adaptation based on beat-to-beat impedance measurements that reflect myocardial contractility and consequently, variations in the patient’s adrenergic tone 1 . Initial studies on CLS efficacy were conducted using conventionally placed right ventricular (RV) apical leads. During CLS, impedance curves are generated from measurements obtained at RV endocardium during systolic phase of the cardiac cycle 2 . Conduction system pacing (CSP), particularly left bundle branch area pacing (LBBAP), has emerged as an increasingly favored pacing approach to achieve a more physiologic pacing response 3 . To date, most investigations have focused on lead hardware and optimal septal pacing implantation sites, while software-based approaches to improve physiological pacing response have received limited attention. CLS in combination with CSP can provide greater physiological improvement. However, the performance of CLS and the accuracy of RV unipolar impedance measurement from deep septal locations remain insufficiently characterized. With the growing adoption of LBBAP, this study aimed to evaluate how lead location within the septum influences the CLS algorithm’s ability to provide appropriate physiological rate adaptation in a large patient cohort. Methodology We conducted a retrospective cohort study using the CERTITUDE registry, a de-identified database containing longitudinal remote monitoring data from over 55,000 U.S. patients with Biotronik pacemakers, implantable cardioverter-defibrillators, cardiac resynchronization therapy devices, and implantable loop recorders active on Home Monitoring (Biotronik SE & Co. KG, Berlin, Germany) 4 . These patients have provided authorization for the use of their data for research purposes. For this project, patients implanted with a dual chamber pacemaker implanted after January 1, 2021, and with at least 6 months of follow-up data were included. Patients with moderate AF (defined as mean AF burden ≥ 20%) and those with low remote transmission index (defined as transmission rate of < 50%) were excluded. LBBAP implantation was documented in the device implant log at the time of the procedure and was used to identify all LBBAP cases. This retrospective analysis was performed using real- world evidence IRB-approved methodologies under a waiver of informed consent and a full waiver of Health Insurance Portability and Accountability Act authorization owing to the minimal risk and observational nature of the analysis. Our objective was to compare the pacing characteristics of DDD-CLS with DDD mode, and to evaluate whether LBBAP versus other right ventricular lead locations (non-LBBAP) influence the performance of the CLS algorithm. The underlying assumption is that the DDD cohort represent distinct pacing characteristics: patients in the DDD cohort are likely less dependent on device-driven rate adaptation and may have relatively preserved sinus node function, whereas those in the DDD- CLS cohort require rate-adaptive pacing. Continuous variables were reported using mean ± SD or median (interquartile range [IQR]), while categorical variables were reported using frequency and percentage. Relevant measures were calculated over three separate 30-day periods: the first 30-day post implant (baseline), the last 30 days of a six-month period post implant, and the last 30 days of a one-year period post implant. Differences between values in the one year and six-month periods were also calculated. These difference values were compared between placement-mode groups for age at implant, mean thoracic impedance, mean ventricular HR, and atrial burden values using Kruskal-Wallis tests. When results from Kruskal-Wallis were significant, pairwise comparisons between each combination of two placement-mode groups were conducted using Mann-Whitney U Tests. Gender between groups was compared with a Fisher’s Exact test. Statistical analysis was performed using SAS 9.4 (SAS Institute, Cary, NC), with a p value < 0.05 considered statistically significant. Results A total of 5,395 patients with dual-chamber pacemakers programmed to either DDD or DDD-CLS were identified from the CERTITUDE database and included in the analysis (Table 1 ). In LBBAP, 267 patients were programmed to DDD-CLS. An additional 148 patients were programmed to DDD. All 415 patients with LBBAP had a Solia S RV lead implanted. Table 1 Patients and device characteristics Baseline Characteristics Group A LBBAP Group B non-LBBAP P-Value DDD-CLS (N = 267) DDD (N = 148) DDD-CLS (N = 3513) DDD (N = 1467) Demographics Age at implant (years) 75.9 ± 9.34 74.4 ± 10.87 75.7 ± 10.05 76.4 ± 9.94 0.143 Male gender 157 (61.3%) 87 (60.8%) 1933 (57.5%) 790 (55.9%) < 0.001 Mean Thoracic Impedance (Ohms) 30 days 55.5 ± 7.19 55.8 ± 7.81 65.6 ± 9.20 64.8 ± 9.10 < 0.001 6 months 69.3 ± 9.08 70.5 ± 9.74 78.9 ± 11.34 78.2 ± 10.90 < 0.001 1 year 70.9 ± 9.67 72.2 ± 9.60 81.0 ± 12.11 80.1 ± 11.66 < 0.001 Difference (6m – 30d) 13.8 ± 5.67 14.5 ± 6.02 13.3 ± 6.51 13.3 ± 6.08 0.031 Difference (1 year – 6m) 1.6 ± 4.34 1.7 ± 3.63 2.1 ± 4.68 1.9 ± 4.48 0.336 Mean ventricular Heart Rate (BPM) 30 days 72.9 ± 5.71 73.8 ± 8.37 72.8 ± 6.04 73.2 ± 7.90 0.675 6 months 72.8 ± 4.93 72.8 ± 7.57 72.9 ± 5.85 72.2 ± 7.58 0.002 1 year 72.9 ± 5.03 72.2 ± 7.40 73.0 ± 5.98 71.7 ± 7.50 < 0.001 Difference (6m – 30d) -0.1 ± 3.51 -1.0 ± 5.50 0.1 ± 3.85 -1.0 ± 4.71 < 0.001 Difference (1 year – 6m) 0.1 ± 2.65 -0.6 ± 3.51 0.1 ± 3.27 -0.5 ± 3.75 < 0.001 Mean atrial arrhythmia burden (% of day) 30 days 0.2 ± 1.34 0.2 ± 0.82 0.2 ± 1.52 0.2 ± 1.48 0.247 6 months 1.5 ± 10.84 1.7 ± 10.64 1.5 ± 10.27 0.9 ± 7.60 0.001 1 year 4.3 ± 19.04 2.4 ± 14.27 2.9 ± 15.19 1.6 ± 10.97 0.019 Difference (6m – 30d) 1.3 ± 10.87 1.6 ± 10.57 1.3 ± 10.12 0.7 ± 7.42 0.050 Difference (1 year – 6m) 2.8 ± 17.94 0.7 ± 10.38 1. 3 ± 13.32 0.7 ± 9.01 0.513 Mean RA Pacing (%) 30 days 69.4 ± 23.93 22.8 ± 25.54 68.5 ± 22.96 22.1 ± 26.08 < 0.001 6 months 71.7 ± 23.24 24.7 ± 26.06 70.5 ± 23.01 24.7 ± 27.21 < 0.001 1 year 68.9 ± 26.46 26.7 ± 26.72 70.0 ± 24.38 26.2 ± 28.29 < 0.001 Difference (6m – 30d) 2.3 ± 15.66 1.9 ± 17.64 2.1 ± 14.79 2.6 ± 14.64 0.439 Difference (1y – 6m) -2.8 ± 17.18 2.0 ± 11.05 -0.5 ± 14.42 1.5 ± 12.13 0.001 Mean RV Pacing (%) 30 days 37.2 ± 43.17 66.4 ± 41.42 24.2 ± 36.86 49.0 ± 45.04 < 0.001 6 months 38.1 ± 43.91 62.5 ± 43.85 25.0 ± 37.70 48.3 ± 45.65 < 0.001 1 year 40.8 ± 44.85 64.4 ± 43.65 26.8 ± 38.67 49.2 ± 45.86 < 0.001 Difference (6m – 30d) 0.9 ± 16.39 -3.9 ± 22.63 0.8 ± 15.97 -0.7 ± 20.26 0.007 Difference (1y – 6m) 2.6 ± 14.52 1.9 ± 11.48 1.8 ± 14.38 1.0 ± 16.42 0.011 Values are mean ± SD or n (%). Bolded cells indicate p < 0.05. Abbreviations: LBBAP, Left Bundle Branch Area Pacing; DDD, Dual-Chamber pacing mode; CLS, Closed-Loop Stimulation; RA, right atrial; RV, right ventricular. For comparison, in the non-LBBAP, 3513 patients were programmed to DDD-CLS, 1467 to DDD. RV lead location was not specified for all patients in this cohort but represents a mixture of apical, septal, and other conventional RV lead implant sites. The mean age of patients across all groups ranged from 74.4 to 76.4 years. There was no significant difference in implant age between the groups. However, compared to other groups, patients with LBBAP and DDD-CLS had a significantly higher proportion of males (P < 0.001). Mean thoracic impedance values were consistently higher in the non-LBBAP groups compared with the LBBAP groups at all time points. In addition, all groups demonstrated a consistent increase in mean thoracic impedance, most notably between 30 days and 6 months after implantation, with a significantly greater increase observed in patients with LBBAP (P = 0.031). However, the change in mean thoracic impedance from 6 months to 1 year did not differ significantly among groups (P = 0.336). Mean ventricular rate increased slightly in the Non-LBBAP, DDD-CLS group between six months (72.9 ± 5.85 bpm) and one year (73.0 ± 5.98 bpm), whereas it decreased in the Non-LBBAP, DDD group (72.2 ± 7.58 bpm to 71.7 ± 7.5 bpm; Table 1 ). This difference in rate change between groups was statistically significant (P < 0.001). However, the mean ventricular heart rate differences between 6 months and 1 year post implant were not different in DDD-CLS patients with LBBAP vs. Non-LAABP pacing position (P = 0.646) (Table 2 ). Table 2 Pairwise Comparisons of Pacing Characteristics Across Pacing Modes and Lead Locations Pairwise Contrast LBBAP, DDD-CLS vs LBBAP, DDD LBBAP, DDD-CLS vs Non-LBBAP, DDD-CLS LBBAP, DDD-CLS vs Non-LBBAP, DDD LBBAP, DDD vs Non-LBBAP, DDD-CLS LBBAP, DDD vs Non-LBBAP, DDD Non-LBBAP, DDD-CLS vs Non-LBBAP, DDD Thoracic Impedance 30d 0.848 < 0.001 < 0.001 < 0.001 < 0.001 0.017 6m 0.483 < 0.001 < 0.001 < 0.001 < 0.001 0.143 1y 0.306 < 0.001 < 0.001 < 0.001 < 0.001 0.074 Difference (6m – 30d) 0.262 0.096 0.185 0.011 0.020 0.585 Ventricular HR 6m 0.741 0.560 0.057 0.674 0.356 < 0.001 1y 0.216 0.568 0.002 0.177 0.437 < 0.001 Difference (6m-30d) 0.217 0.946 < 0.001 0.090 0.361 < 0.001 (1y-6m) 0.061 0.646 0.006 0.053 0.942 < 0.001 Atrial Burden 6m 0.487 0.350 0.285 0.917 0.078 < 0.001 1y 0.601 0.925 0.105 0.566 0.560 0.002 Difference (6m-30d) 0.705 0.591 0.410 0.406 0.894 0.006 RA Pacing 30d < 0.001 0.326 < 0.001 < 0.001 0.958 < 0.001 6m < 0.001 0.336 < 0.001 < 0.001 0.983 < 0.001 1y < 0.001 0.855 < 0.001 < 0.001 0.618 < 0.001 Difference (1y-6m) 0.011 0.057 0.002 0.095 0.533 0.004 RV Pacing 30d < 0.001 0.001 0.002 < 0.001 0.001 < 0.001 6m < 0.001 0.001 0.018 < 0.001 0.004 < 0.001 1y < 0.001 0.001 0.096 < 0.001 0.002 < 0.001 Difference (6m-30d) 0.115 0.844 0.290 0.031 0.269 0.004 Difference (1y-6m) 0.561 0.716 0.068 0.647 0.533 0.001 P-values from Mann-Whitney U test and unadjusted for multiplicity. Bolded cells indicate p < 0.05. Abbreviations: LBBAP, Left Bundle Branch Area Pacing; DDD, Dual-Chamber pacing mode; CLS, Closed-Loop Stimulation; HR, heart rate; RA, right atrial; RV, right ventricular. Among patients with non-LBBAP, atrial arrhythmia burden was significantly higher in those programmed to DDD-CLS compared with DDD at both 6 months and 1-year post-implant. This difference was not observed in patients with LBBAP. However, the change in atrial arrhythmia burden from 6 months to 1 year did not differ significantly across pacing modes or lead locations. As expected, right atrial pacing percentage was higher in patients programmed to CLS mode, regardless of lead location. However, atrial pacing burden decreased over time in both CLS groups. There was no significant difference in atrial pacing burden between the LBBAP DDD-CLS group and the non-LBBAP DDD-CLS group at any evaluated time point (Table 2 ). In contrast, right ventricular pacing burden was significantly higher in patients programmed to DDD mode compared with those programmed to DDD-CLS at 30 days, 6 months, and 1 year (P < 0.001). When comparing patients with LBBAP DDD-CLS to those with non-LBBAP DDD-CLS, the burden of ventricular pacing was significantly higher in the LBBAP group at all points (30 days, 6 months, and 1 year; P < 0.001). However, there were no significant changes in ventricular pacing burden over time, either between 30 days and 6 months (P = 0.844) or between 6 months and 1 year (P = 0.716) Discussion Better implantation tools have facilitated broader adoption of LBBAP, not just in patients with pacemakers but also for patients with ICD or CRT indication. While hardware considerations in restoring physiological conduction remain at the forefront, the benefits of physiological rate adaptation should also be recognized, as they contribute to the overarching goal of physiological pacing. To that end, physiological rate adaption algorithms such as CLS should be evaluated further to better define therapeutic benefits for patients, regardless of device type, lead locations or device/lead configuration. As lead placement options and implantation techniques have evolved, several studies have reported no measurable impact on the efficacy of CLS, with a change in lead location. Publications on lead placement in RV apex 5 , RV septum 6 , right ventricular outflow tract 6 , His bundle 7 , and even epicardial coronary venous lead placements, 8 have consistently demonstrated preserved CLS performance independent of lead tip location. In our study, the stability of heart rate behavior, thoracic impedance, and atrial arrhythmia burden between LBBAP and non-LBBAP groups supports the notion that CLS functionality remains intact and effective when combined with conduction system pacing. The lack of difference in ventricular rate response and impedance change over time suggests that the CLS algorithm adapts appropriately to physiological demands irrespective of lead position or pacing site. Atrial arrhythmia burden was comparable across pacing modes and lead locations, except for a higher burden in the non-LBBAP DDD-CLS group compared with the non-LBBAP DDD group. CLS pacing itself has not been shown to increase atrial arrhythmia burden 9 ; however, in patients with high atrial pacing percentages—particularly in the setting of non-physiologic ventricular pacing—an increased atrial arrhythmias may be observed . In addition, our findings are consistent with those of Dell’Era et al. 10 , who observed that LBBAP lead position does not adversely affect the rate-responsive performance of CLS. Together, these data reinforce that CLS remains compatible with conduction system pacing and may serve as a valuable adjunct in achieving a more complete physiologic pacing strategy. Future prospective studies with longer follow-up and clinical outcome assessment will be essential to further characterize the synergy between LBBAP and CLS, particularly regarding exercise tolerance, heart failure progression, and arrhythmia risk. Limitations This study has several limitations. First, it was a retrospective analysis of the CERTITUDE registry, which, although large and comprehensive, is an observational database and therefore subject to inherent confounding and selection bias. Second, RV lead position was not specifically annotated, limiting direct comparison between LBBAP and conventional RV pacing sites. Third, follow-up was limited to one year, and the study did not evaluate detailed clinical outcomes such as exercise capacity, heart failure hospitalization, or mortality. These factors should be considered when interpreting the observed differences in pacing characteristics and rate response. Conclusion In this retrospective real-world analysis of 5683 patients with dual-chamber pacemakers, implanting the lead in the LBBA results in similar pacing metrics for the DDD-CLS groups as observed in the DDD group. CLS efficacy does not appear to be negatively impacted in any way when positioned in the LBBA. Abbreviations CLS= closed loop stimulation CSP= conduction system pacing LBBA= left bundle branch area LBBAP= left bundle branch area pacing RA= right atrial RV= right ventricular Declarations Sources of Funding CERTITUDE program activities are supported financially by BIOTRONIK, Inc. Conflicts of Interest: BS, MS, CH, CM, and DH are salaried employees of BIOTRONIK, Inc. Disclosures: Non to disclose Competing Interests First author has no competing financial interest. However, all other co-authors are employed by Biotronik. We used data registry of Biotronik company for this study. Author Contribution H.Y. wrote the main manuscript text and B.S, M.S, C.H, C.M prepared tables, run statistics and provide data analysis. D. H edit and revised the manuscript. All authors reviewed the manuscript." References Pieragnoli P, Colella A, Michelucci A, et al. A new algorithm for closed-loop stimulation: a feasibility study. Pacing Clin Electrophysiol . 2003;26(1P2):229-232. doi:10.1046/j.1460-9592.2003.00022.x Tomaino M, Russo V, Giacopelli D, Gargaro A, Brignole M. Cardiac Pacing in Cardioinhibitory Reflex Syncope: Clinical Use of Closed-loop Stimulation. Arrhythm Electrophysiol Rev . 2021;10(4):244-249. doi:10.15420/aer.2021.45 Burri H, Jastrzebski M, Cano Ó, et al. EHRA clinical consensus statement on conduction system pacing implantation: endorsed by the Asia Pacific Heart Rhythm Society (APHRS), Canadian Heart Rhythm Society (CHRS), and Latin American Heart Rhythm Society (LAHRS). Europace . 2023;25(4):1208-1236. doi:10.1093/europace/euad043 Deshmukh AJ, Harrell C, Hicks J, et al. Physical Activity in Cardiac Implantable Electronic Device Recipients During the COVID-19 Pandemic. Mayo Clin Proc . 2022;97(8):1493-1500. doi:10.1016/j.mayocp.2022.01.025 Drago F, Silvetti MS, De Santis A, et al. Closed loop stimulation improves ejection fraction in pediatric patients with pacemaker and ventricular dysfunction. Pacing Clin Electrophysiol . 2007;30(1):33-37. doi:10.1111/j.1540-8159.2007.00576.x Lindovská M, Kameník L, Pollock B, et al. Clinical observations with Closed Loop Stimulation pacemakers in a large patient cohort: the CYLOS routine documentation registry (RECORD). Europace . 2012;14(11):1587-1595. doi:10.1093/europace/eus062 Marinaccio L, Giacopelli D, Ginocchio G, Vetta F, Marchese D. Closed loop stimulation with His bundle lead placement. J Cardiol Cases . 2022;26(2):126-129. doi:10.1016/j.jccase.2022.03.015 Ikeya Y, Nakai T, Murata N, et al. Effective Pacing Intervention by Closed-loop Stimulation Using a Coronary Vein Lead in a Post-tricuspid Valve Replacement Patient. Intern Med . 2020;59(7):963-966. doi:10.2169/internal medicine.4018-19 Ikeda S, Nogami A, Inoue K, et al. Closed-loop stimulation as a physiological rate-modulated pacing approach based on intracardiac impedance to lower the atrial tachyarrhythmia burden in patients with sinus node dysfunction and atrial fibrillation. J Cardiovasc Electrophysiol . 2020;31(5):1187-1194. doi:10.1111/jce.14430 Dell’Era G, Ghiglieno C, De Vecchi F, et al. Closed loop stimulation in left bundle branch area pacing. Pacing Clin Electrophysiol . 2024;47(9):1276-1279. doi:10.1111/pace.15022 Additional Declarations Competing interest reported. First author has no competing financial interest. However, all other co-authors are employed by Biotronik. We used data registry of Biotronik company for this study. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8897052","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":594093483,"identity":"4626779e-5051-43ab-9384-0b0e8ad4995f","order_by":0,"name":"Hirad Yarmohammadi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYBACAwbm4x8+/rOB8S0YGCQYG4AMZjxa2NIYZ7ClwfgSxGjhMWPmYDuMrAXMwK3FXCLB7DEDz3l5g2uHHzD8qJBIXDu7ufEDQ4V1YgMOLZYzEtKNCyRuG264nWbA2HNGInHbnYPNEgxn0nFqMbiRcEB6hsHtBIPbOQzMjG1ALTcSGyQY2w7j0ZLYIM2TcA5FS/MPxn/4tCSzSfMcOICipQ0YaHi0nHnGbDizIdlwJtAvB4F+MQb6pc0i4Vi6MU4tx/M/PvjYYCfPdzv54YMfFTay2263P77xocZaFpcWBoEEBPsAnJWArgwZ8B/AJzsKRsEoGAWjAAgA4chjPjtmtwUAAAAASUVORK5CYII=","orcid":"","institution":"Columbia University Irving Medical Center","correspondingAuthor":true,"prefix":"","firstName":"Hirad","middleName":"","lastName":"Yarmohammadi","suffix":""},{"id":594093486,"identity":"7d65d441-7523-4572-97ae-e6ff0818622a","order_by":1,"name":"Bobak Salehi","email":"","orcid":"","institution":"Biotronik Inc","correspondingAuthor":false,"prefix":"","firstName":"Bobak","middleName":"","lastName":"Salehi","suffix":""},{"id":594093487,"identity":"3bf00d24-9f03-4916-b7f9-6205bd2c73c1","order_by":2,"name":"Margaret Shea","email":"","orcid":"","institution":"Biotronik Inc","correspondingAuthor":false,"prefix":"","firstName":"Margaret","middleName":"","lastName":"Shea","suffix":""},{"id":594093489,"identity":"2021d8cd-a96b-4c66-aa37-f5e6960414b3","order_by":3,"name":"Camden Harrell","email":"","orcid":"","institution":"Biotronik Inc","correspondingAuthor":false,"prefix":"","firstName":"Camden","middleName":"","lastName":"Harrell","suffix":""},{"id":594093491,"identity":"f8920c31-f3bd-412e-8a43-2a7f24b5969f","order_by":4,"name":"Crystal Miller","email":"","orcid":"","institution":"Biotronik Inc","correspondingAuthor":false,"prefix":"","firstName":"Crystal","middleName":"","lastName":"Miller","suffix":""},{"id":594093492,"identity":"dabdd57d-dd6a-4669-bdee-c98a06c425de","order_by":5,"name":"David Hayes","email":"","orcid":"","institution":"Biotronik Inc","correspondingAuthor":false,"prefix":"","firstName":"David","middleName":"","lastName":"Hayes","suffix":""}],"badges":[],"createdAt":"2026-02-17 02:38:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8897052/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8897052/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103504536,"identity":"c37d2d71-c41e-4466-bfb4-85e93069df8e","added_by":"auto","created_at":"2026-02-26 13:20:27","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1018366,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8897052/v1/f94a7803-3ab9-4c28-b831-b0e34ebaebe9.pdf"}],"financialInterests":"Competing interest reported. First author has no competing financial interest. However, all other co-authors are employed by Biotronik. We used data registry of Biotronik company for this study.","formattedTitle":"Efficacy of Closed Loop Stimulation in Left Bundle Branch Area Pacing","fulltext":[{"header":"Introduction","content":"\u003cp\u003eClosed Loop Stimulation (CLS) algorithm is designed to regulate paced rate-adaptation based on beat-to-beat impedance measurements that reflect myocardial contractility and consequently, variations in the patient\u0026rsquo;s adrenergic tone \u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Initial studies on CLS efficacy were conducted using conventionally placed right ventricular (RV) apical leads. During CLS, impedance curves are generated from measurements obtained at RV endocardium during systolic phase of the cardiac cycle \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eConduction system pacing (CSP), particularly left bundle branch area pacing (LBBAP), has emerged as an increasingly favored pacing approach to achieve a more physiologic pacing response \u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. To date, most investigations have focused on lead hardware and optimal septal pacing implantation sites, while software-based approaches to improve physiological pacing response have received limited attention.\u003c/p\u003e \u003cp\u003eCLS in combination with CSP can provide greater physiological improvement. However, the performance of CLS and the accuracy of RV unipolar impedance measurement from deep septal locations remain insufficiently characterized. With the growing adoption of LBBAP, this study aimed to evaluate how lead location within the septum influences the CLS algorithm\u0026rsquo;s ability to provide appropriate physiological rate adaptation in a large patient cohort.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003eWe conducted a retrospective cohort study using the CERTITUDE registry, a de-identified database containing longitudinal remote monitoring data from over 55,000 U.S. patients with Biotronik pacemakers, implantable cardioverter-defibrillators, cardiac resynchronization therapy devices, and implantable loop recorders active on Home Monitoring (Biotronik SE \u0026amp; Co. KG, Berlin, Germany) \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. These patients have provided authorization for the use of their data for research purposes. For this project, patients implanted with a dual chamber pacemaker implanted after January 1, 2021, and with at least 6 months of follow-up data were included. Patients with moderate AF (defined as mean AF burden\u0026thinsp;\u0026ge;\u0026thinsp;20%) and those with low remote transmission index (defined as transmission rate of \u0026lt;\u0026thinsp;50%) were excluded. LBBAP implantation was documented in the device implant log at the time of the procedure and was used to identify all LBBAP cases.\u003c/p\u003e \u003cp\u003eThis retrospective analysis was performed using real- world evidence IRB-approved methodologies under a waiver of informed consent and a full waiver of Health Insurance Portability and Accountability Act authorization owing to the minimal risk and observational nature of the analysis.\u003c/p\u003e \u003cp\u003eOur objective was to compare the pacing characteristics of DDD-CLS with DDD mode, and to evaluate whether LBBAP versus other right ventricular lead locations (non-LBBAP) influence the performance of the CLS algorithm. The underlying assumption is that the DDD cohort represent distinct pacing characteristics: patients in the DDD cohort are likely less dependent on device-driven rate adaptation and may have relatively preserved sinus node function, whereas those in the DDD- CLS cohort require rate-adaptive pacing.\u003c/p\u003e \u003cp\u003eContinuous variables were reported using mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD or median (interquartile range [IQR]), while categorical variables were reported using frequency and percentage. Relevant measures were calculated over three separate 30-day periods: the first 30-day post implant (baseline), the last 30 days of a six-month period post implant, and the last 30 days of a one-year period post implant. Differences between values in the one year and six-month periods were also calculated. These difference values were compared between placement-mode groups for age at implant, mean thoracic impedance, mean ventricular HR, and atrial burden values using Kruskal-Wallis tests. When results from Kruskal-Wallis were significant, pairwise comparisons between each combination of two placement-mode groups were conducted using Mann-Whitney U Tests. Gender between groups was compared with a Fisher\u0026rsquo;s Exact test. Statistical analysis was performed using SAS 9.4 (SAS Institute, Cary, NC), with a p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 5,395 patients with dual-chamber pacemakers programmed to either DDD or DDD-CLS were identified from the CERTITUDE database and included in the analysis (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In LBBAP, 267 patients were programmed to DDD-CLS. An additional 148 patients were programmed to DDD. All 415 patients with LBBAP had a Solia S RV lead implanted.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePatients and device characteristics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eBaseline Characteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eGroup A\u003c/p\u003e \u003cp\u003eLBBAP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eGroup B\u003c/p\u003e \u003cp\u003enon-LBBAP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eP-Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDDD-CLS\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;267)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDDD\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;148)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDDD-CLS\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;3513)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eDDD\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;1467)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eDemographics\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge at implant (years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e75.9\u0026thinsp;\u0026plusmn;\u0026thinsp;9.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e74.4\u0026thinsp;\u0026plusmn;\u0026thinsp;10.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e75.7\u0026thinsp;\u0026plusmn;\u0026thinsp;10.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e76.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.143\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale gender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e157 (61.3%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e87 (60.8%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1933 (57.5%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e790 (55.9%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMean Thoracic Impedance (Ohms)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e55.5\u0026thinsp;\u0026plusmn;\u0026thinsp;7.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e55.8\u0026thinsp;\u0026plusmn;\u0026thinsp;7.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e65.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e64.8\u0026thinsp;\u0026plusmn;\u0026thinsp;9.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e69.3\u0026thinsp;\u0026plusmn;\u0026thinsp;9.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e70.5\u0026thinsp;\u0026plusmn;\u0026thinsp;9.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e78.9\u0026thinsp;\u0026plusmn;\u0026thinsp;11.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e78.2\u0026thinsp;\u0026plusmn;\u0026thinsp;10.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70.9\u0026thinsp;\u0026plusmn;\u0026thinsp;9.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72.2\u0026thinsp;\u0026plusmn;\u0026thinsp;9.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.0\u0026thinsp;\u0026plusmn;\u0026thinsp;12.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80.1\u0026thinsp;\u0026plusmn;\u0026thinsp;11.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.8\u0026thinsp;\u0026plusmn;\u0026thinsp;5.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e14.5\u0026thinsp;\u0026plusmn;\u0026thinsp;6.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.3\u0026thinsp;\u0026plusmn;\u0026thinsp;6.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.3\u0026thinsp;\u0026plusmn;\u0026thinsp;6.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.031\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1\u0026nbsp;year \u0026ndash; 6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.6\u0026thinsp;\u0026plusmn;\u0026thinsp;4.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;3.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.336\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMean ventricular Heart Rate (BPM)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e73.8\u0026thinsp;\u0026plusmn;\u0026thinsp;8.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.8\u0026thinsp;\u0026plusmn;\u0026thinsp;6.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e73.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.675\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72.8\u0026thinsp;\u0026plusmn;\u0026thinsp;4.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72.8\u0026thinsp;\u0026plusmn;\u0026thinsp;7.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e72.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e72.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e72.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e73.0\u0026thinsp;\u0026plusmn;\u0026thinsp;5.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e71.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-0.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-1.0\u0026thinsp;\u0026plusmn;\u0026thinsp;5.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-1.0\u0026thinsp;\u0026plusmn;\u0026thinsp;4.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1\u0026nbsp;year \u0026ndash; 6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-0.6\u0026thinsp;\u0026plusmn;\u0026thinsp;3.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.1\u0026thinsp;\u0026plusmn;\u0026thinsp;3.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-0.5\u0026thinsp;\u0026plusmn;\u0026thinsp;3.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMean atrial arrhythmia burden (% of day)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;0.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.2\u0026thinsp;\u0026plusmn;\u0026thinsp;1.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.247\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.5\u0026thinsp;\u0026plusmn;\u0026thinsp;10.84\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.7\u0026thinsp;\u0026plusmn;\u0026thinsp;10.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.5\u0026thinsp;\u0026plusmn;\u0026thinsp;10.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.9\u0026thinsp;\u0026plusmn;\u0026thinsp;7.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.3\u0026thinsp;\u0026plusmn;\u0026thinsp;19.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.4\u0026thinsp;\u0026plusmn;\u0026thinsp;14.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.9\u0026thinsp;\u0026plusmn;\u0026thinsp;15.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.6\u0026thinsp;\u0026plusmn;\u0026thinsp;10.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.019\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.3\u0026thinsp;\u0026plusmn;\u0026thinsp;10.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.6\u0026thinsp;\u0026plusmn;\u0026thinsp;10.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.3\u0026thinsp;\u0026plusmn;\u0026thinsp;10.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.050\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1\u0026nbsp;year \u0026ndash; 6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;17.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;10.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1. 3\u0026thinsp;\u0026plusmn;\u0026thinsp;13.32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;9.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.513\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMean RA Pacing (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e69.4\u0026thinsp;\u0026plusmn;\u0026thinsp;23.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.8\u0026thinsp;\u0026plusmn;\u0026thinsp;25.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e68.5\u0026thinsp;\u0026plusmn;\u0026thinsp;22.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e22.1\u0026thinsp;\u0026plusmn;\u0026thinsp;26.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e71.7\u0026thinsp;\u0026plusmn;\u0026thinsp;23.24\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24.7\u0026thinsp;\u0026plusmn;\u0026thinsp;26.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.5\u0026thinsp;\u0026plusmn;\u0026thinsp;23.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e24.7\u0026thinsp;\u0026plusmn;\u0026thinsp;27.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e68.9\u0026thinsp;\u0026plusmn;\u0026thinsp;26.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26.7\u0026thinsp;\u0026plusmn;\u0026thinsp;26.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e70.0\u0026thinsp;\u0026plusmn;\u0026thinsp;24.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.2\u0026thinsp;\u0026plusmn;\u0026thinsp;28.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.3\u0026thinsp;\u0026plusmn;\u0026thinsp;15.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;17.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.1\u0026thinsp;\u0026plusmn;\u0026thinsp;14.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.6\u0026thinsp;\u0026plusmn;\u0026thinsp;14.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.439\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1y \u0026ndash; 6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-2.8\u0026thinsp;\u0026plusmn;\u0026thinsp;17.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.0\u0026thinsp;\u0026plusmn;\u0026thinsp;11.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-0.5\u0026thinsp;\u0026plusmn;\u0026thinsp;14.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.5\u0026thinsp;\u0026plusmn;\u0026thinsp;12.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eMean RV Pacing (%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e37.2\u0026thinsp;\u0026plusmn;\u0026thinsp;43.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e66.4\u0026thinsp;\u0026plusmn;\u0026thinsp;41.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e24.2\u0026thinsp;\u0026plusmn;\u0026thinsp;36.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e49.0\u0026thinsp;\u0026plusmn;\u0026thinsp;45.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6 months\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e38.1\u0026thinsp;\u0026plusmn;\u0026thinsp;43.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e62.5\u0026thinsp;\u0026plusmn;\u0026thinsp;43.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.0\u0026thinsp;\u0026plusmn;\u0026thinsp;37.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e48.3\u0026thinsp;\u0026plusmn;\u0026thinsp;45.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1 year\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40.8\u0026thinsp;\u0026plusmn;\u0026thinsp;44.85\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e64.4\u0026thinsp;\u0026plusmn;\u0026thinsp;43.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e26.8\u0026thinsp;\u0026plusmn;\u0026thinsp;38.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e49.2\u0026thinsp;\u0026plusmn;\u0026thinsp;45.86\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.9\u0026thinsp;\u0026plusmn;\u0026thinsp;16.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-3.9\u0026thinsp;\u0026plusmn;\u0026thinsp;22.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.8\u0026thinsp;\u0026plusmn;\u0026thinsp;15.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-0.7\u0026thinsp;\u0026plusmn;\u0026thinsp;20.26\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.007\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1y \u0026ndash; 6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.6\u0026thinsp;\u0026plusmn;\u0026thinsp;14.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.9\u0026thinsp;\u0026plusmn;\u0026thinsp;11.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.8\u0026thinsp;\u0026plusmn;\u0026thinsp;14.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.0\u0026thinsp;\u0026plusmn;\u0026thinsp;16.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003eValues are mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD or n (%). Bolded cells indicate p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Abbreviations: LBBAP, Left Bundle Branch Area Pacing; DDD, Dual-Chamber pacing mode; CLS, Closed-Loop Stimulation; RA, right atrial; RV, right ventricular.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eFor comparison, in the non-LBBAP, 3513 patients were programmed to DDD-CLS, 1467 to DDD. RV lead location was not specified for all patients in this cohort but represents a mixture of apical, septal, and other conventional RV lead implant sites.\u003c/p\u003e \u003cp\u003eThe mean age of patients across all groups ranged from 74.4 to 76.4 years. There was no significant difference in implant age between the groups. However, compared to other groups, patients with LBBAP and DDD-CLS had a significantly higher proportion of males (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e \u003cp\u003eMean thoracic impedance values were consistently higher in the non-LBBAP groups compared with the LBBAP groups at all time points. In addition, all groups demonstrated a consistent increase in mean thoracic impedance, most notably between 30 days and 6 months after implantation, with a significantly greater increase observed in patients with LBBAP (P\u0026thinsp;=\u0026thinsp;0.031). However, the change in mean thoracic impedance from 6 months to 1 year did not differ significantly among groups (P\u0026thinsp;=\u0026thinsp;0.336).\u003c/p\u003e \u003cp\u003eMean ventricular rate increased slightly in the Non-LBBAP, DDD-CLS group between six months (72.9\u0026thinsp;\u0026plusmn;\u0026thinsp;5.85 bpm) and one year (73.0\u0026thinsp;\u0026plusmn;\u0026thinsp;5.98 bpm), whereas it decreased in the Non-LBBAP, DDD group (72.2\u0026thinsp;\u0026plusmn;\u0026thinsp;7.58 bpm to 71.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.5 bpm; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). This difference in rate change between groups was statistically significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, the mean ventricular heart rate differences between 6 months and 1 year post implant were not different in DDD-CLS patients with LBBAP vs. Non-LAABP pacing position (P\u0026thinsp;=\u0026thinsp;0.646) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePairwise Comparisons of Pacing Characteristics Across Pacing Modes and Lead Locations\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePairwise Contrast\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLBBAP, DDD-CLS vs LBBAP, DDD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLBBAP, DDD-CLS vs Non-LBBAP, DDD-CLS\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLBBAP, DDD-CLS vs Non-LBBAP, DDD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLBBAP, DDD vs Non-LBBAP, DDD-CLS\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eLBBAP, DDD vs Non-LBBAP, DDD\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eNon-LBBAP, DDD-CLS vs Non-LBBAP, DDD\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eThoracic Impedance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.848\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.017\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6m\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.483\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.143\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.306\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.074\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m \u0026ndash; 30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.262\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.096\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.185\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.020\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e0.585\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVentricular HR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6m\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.741\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.560\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.057\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.674\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.356\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.216\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.568\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.177\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.437\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m-30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.217\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.946\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.090\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.361\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e(1y-6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.061\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.646\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.053\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.942\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAtrial Burden\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6m\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.487\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.350\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.285\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.917\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.601\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.925\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.105\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.566\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.560\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m-30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.705\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.591\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.410\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.406\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.894\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRA Pacing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.326\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.958\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6m\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.336\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.983\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.855\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.618\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1y-6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.057\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.095\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.533\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRV Pacing\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e30d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6m\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.018\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.096\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (6m-30d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.115\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.844\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.290\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.031\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.269\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDifference (1y-6m)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.561\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.716\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.068\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.647\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.533\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eP-values from Mann-Whitney U test and unadjusted for multiplicity. Bolded cells indicate p\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Abbreviations: LBBAP, Left Bundle Branch Area Pacing; DDD, Dual-Chamber pacing mode; CLS, Closed-Loop Stimulation; HR, heart rate; RA, right atrial; RV, right ventricular.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAmong patients with non-LBBAP, atrial arrhythmia burden was significantly higher in those programmed to DDD-CLS compared with DDD at both 6 months and 1-year post-implant. This difference was not observed in patients with LBBAP. However, the change in atrial arrhythmia burden from 6 months to 1 year did not differ significantly across pacing modes or lead locations.\u003c/p\u003e \u003cp\u003eAs expected, right atrial pacing percentage was higher in patients programmed to CLS mode, regardless of lead location. However, atrial pacing burden decreased over time in both CLS groups. There was no significant difference in atrial pacing burden between the LBBAP DDD-CLS group and the non-LBBAP DDD-CLS group at any evaluated time point (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn contrast, right ventricular pacing burden was significantly higher in patients programmed to DDD mode compared with those programmed to DDD-CLS at 30 days, 6 months, and 1 year (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). When comparing patients with LBBAP DDD-CLS to those with non-LBBAP DDD-CLS, the burden of ventricular pacing was significantly higher in the LBBAP group at all points (30 days, 6 months, and 1 year; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). However, there were no significant changes in ventricular pacing burden over time, either between 30 days and 6 months (P\u0026thinsp;=\u0026thinsp;0.844) or between 6 months and 1 year (P\u0026thinsp;=\u0026thinsp;0.716)\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eBetter implantation tools have facilitated broader adoption of LBBAP, not just in patients with pacemakers but also for patients with ICD or CRT indication. While hardware considerations in restoring physiological conduction remain at the forefront, the benefits of physiological rate adaptation should also be recognized, as they contribute to the overarching goal of physiological pacing. To that end, physiological rate adaption algorithms such as CLS should be evaluated further to better define therapeutic benefits for patients, regardless of device type, lead locations or device/lead configuration.\u003c/p\u003e \u003cp\u003eAs lead placement options and implantation techniques have evolved, several studies have reported no measurable impact on the efficacy of CLS, with a change in lead location. Publications on lead placement in RV apex \u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e, RV septum \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e, right ventricular outflow tract \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e, His bundle \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e, and even epicardial coronary venous lead placements, \u003csup\u003e8\u003c/sup\u003e have consistently demonstrated preserved CLS performance independent of lead tip location.\u003c/p\u003e \u003cp\u003eIn our study, the stability of heart rate behavior, thoracic impedance, and atrial arrhythmia burden between LBBAP and non-LBBAP groups supports the notion that CLS functionality remains intact and effective when combined with conduction system pacing. The lack of difference in ventricular rate response and impedance change over time suggests that the CLS algorithm adapts appropriately to physiological demands irrespective of lead position or pacing site.\u003c/p\u003e \u003cp\u003eAtrial arrhythmia burden was comparable across pacing modes and lead locations, except for a higher burden in the non-LBBAP DDD-CLS group compared with the non-LBBAP DDD group. CLS pacing itself has not been shown to increase atrial arrhythmia burden \u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e; however, in patients with high atrial pacing percentages\u0026mdash;particularly in the setting of non-physiologic ventricular pacing\u0026mdash;an increased atrial arrhythmias may be observed .\u003c/p\u003e \u003cp\u003eIn addition, our findings are consistent with those of Dell\u0026rsquo;Era et al.\u003csup\u003e10\u003c/sup\u003e, who observed that LBBAP lead position does not adversely affect the rate-responsive performance of CLS. Together, these data reinforce that CLS remains compatible with conduction system pacing and may serve as a valuable adjunct in achieving a more complete physiologic pacing strategy. Future prospective studies with longer follow-up and clinical outcome assessment will be essential to further characterize the synergy between LBBAP and CLS, particularly regarding exercise tolerance, heart failure progression, and arrhythmia risk.\u003c/p\u003e\n\u003ch3\u003eLimitations\u003c/h3\u003e\n\u003cp\u003eThis study has several limitations. First, it was a retrospective analysis of the CERTITUDE registry, which, although large and comprehensive, is an observational database and therefore subject to inherent confounding and selection bias. Second, RV lead position was not specifically annotated, limiting direct comparison between LBBAP and conventional RV pacing sites. Third, follow-up was limited to one year, and the study did not evaluate detailed clinical outcomes such as exercise capacity, heart failure hospitalization, or mortality. These factors should be considered when interpreting the observed differences in pacing characteristics and rate response.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn this retrospective real-world analysis of 5683 patients with dual-chamber pacemakers, implanting the lead in the LBBA results in similar pacing metrics for the DDD-CLS groups as observed in the DDD group. CLS efficacy does not appear to be negatively impacted in any way when positioned in the LBBA.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCLS= closed loop stimulation\u003c/p\u003e\n\u003cp\u003eCSP= conduction system pacing\u003c/p\u003e\n\u003cp\u003eLBBA= left bundle branch area\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLBBAP= left bundle branch area pacing\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRA= right atrial\u003c/p\u003e\n\u003cp\u003eRV= right ventricular\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eSources of Funding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCERTITUDE program activities are supported financially by BIOTRONIK, Inc.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBS, MS, CH, CM, and DH are salaried employees of BIOTRONIK, Inc.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclosures:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNon to disclose\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFirst author has no competing financial interest. However, all other co-authors are employed by Biotronik. We used data registry of Biotronik company for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eH.Y. wrote the main manuscript text and B.S, M.S, C.H, C.M prepared tables, run statistics and provide data analysis. D. H edit and revised the manuscript. All authors reviewed the manuscript.\u0026quot;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003ePieragnoli P, Colella A, Michelucci A, et al. A new algorithm for closed-loop stimulation: a feasibility study. \u003cem\u003ePacing Clin Electrophysiol\u003c/em\u003e. 2003;26(1P2):229-232. doi:10.1046/j.1460-9592.2003.00022.x\u003c/li\u003e\n\u003cli\u003eTomaino M, Russo V, Giacopelli D, Gargaro A, Brignole M. Cardiac Pacing in Cardioinhibitory Reflex Syncope: Clinical Use of Closed-loop Stimulation. \u003cem\u003eArrhythm Electrophysiol Rev\u003c/em\u003e. 2021;10(4):244-249. doi:10.15420/aer.2021.45\u003c/li\u003e\n\u003cli\u003eBurri H, Jastrzebski M, Cano \u0026Oacute;, et al. EHRA clinical consensus statement on conduction system pacing implantation: endorsed by the Asia Pacific Heart Rhythm Society (APHRS), Canadian Heart Rhythm Society (CHRS), and Latin American Heart Rhythm Society (LAHRS). \u003cem\u003eEuropace\u003c/em\u003e. 2023;25(4):1208-1236. doi:10.1093/europace/euad043\u003c/li\u003e\n\u003cli\u003eDeshmukh AJ, Harrell C, Hicks J, et al. Physical Activity in Cardiac Implantable Electronic Device Recipients During the COVID-19 Pandemic. \u003cem\u003eMayo Clin Proc\u003c/em\u003e. 2022;97(8):1493-1500. doi:10.1016/j.mayocp.2022.01.025\u003c/li\u003e\n\u003cli\u003eDrago F, Silvetti MS, De Santis A, et al. Closed loop stimulation improves ejection fraction in pediatric patients with pacemaker and ventricular dysfunction. \u003cem\u003ePacing Clin Electrophysiol\u003c/em\u003e. 2007;30(1):33-37. doi:10.1111/j.1540-8159.2007.00576.x\u003c/li\u003e\n\u003cli\u003eLindovsk\u0026aacute; M, Kamen\u0026iacute;k L, Pollock B, et al. Clinical observations with Closed Loop Stimulation pacemakers in a large patient cohort: the CYLOS routine documentation registry (RECORD). \u003cem\u003eEuropace\u003c/em\u003e. 2012;14(11):1587-1595. doi:10.1093/europace/eus062\u003c/li\u003e\n\u003cli\u003eMarinaccio L, Giacopelli D, Ginocchio G, Vetta F, Marchese D. Closed loop stimulation with His bundle lead placement. \u003cem\u003eJ Cardiol Cases\u003c/em\u003e. 2022;26(2):126-129. doi:10.1016/j.jccase.2022.03.015\u003c/li\u003e\n\u003cli\u003eIkeya Y, Nakai T, Murata N, et al. Effective Pacing Intervention by Closed-loop Stimulation Using a Coronary Vein Lead in a Post-tricuspid Valve Replacement Patient. \u003cem\u003eIntern Med\u003c/em\u003e. 2020;59(7):963-966. doi:10.2169/internal medicine.4018-19\u003c/li\u003e\n\u003cli\u003eIkeda S, Nogami A, Inoue K, et al. Closed-loop stimulation as a physiological rate-modulated pacing approach based on intracardiac impedance to lower the atrial tachyarrhythmia burden in patients with sinus node dysfunction and atrial fibrillation. \u003cem\u003eJ Cardiovasc Electrophysiol\u003c/em\u003e. 2020;31(5):1187-1194. doi:10.1111/jce.14430\u003c/li\u003e\n\u003cli\u003eDell\u0026rsquo;Era G, Ghiglieno C, De Vecchi F, et al. Closed loop stimulation in left bundle branch area pacing. \u003cem\u003ePacing Clin Electrophysiol\u003c/em\u003e. 2024;47(9):1276-1279. doi:10.1111/pace.15022\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Closed loop stimulation, left bundle branch area pacing, rate-adaptation, pacemaker","lastPublishedDoi":"10.21203/rs.3.rs-8897052/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8897052/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eClosed-Loop Stimulation (CLS) adjusts pacing rate based on beat-to-beat impedance changes reflecting myocardial contractility and autonomic tone. While early studies focused on right ventricular apical leads, conduction system pacing, particularly left bundle branch area pacing (LBBAP) offers a more physiologic approach. The effect of septal lead position on CLS performance remains unclear.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eTo investigate the impact of LBBAP versus alternative right ventricular lead positions on CLS performance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eWe conducted a retrospective cohort study using the CERTITUDE registry, which includes longitudinal remote monitoring data from over 55,000 U.S. patients with Biotronik devices. Patients with dual-chamber pacemakers implanted after January 1, 2021, with ≥6 months of follow-up were included, excluding those with ≥20% atrial fibrillation burden or \u0026lt;50% transmission rate. Pacing characteristics were compared across DDD and DDD-CLS modes and between LBBAP and non-LBBAP lead locations\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eA total of 5,395 patients were included. Baseline mean thoracic impedance was higher in non-LBBAP groups (P\u0026lt;0.001), though changes over time were not significant (P=0.336). Mean ventricular rate increased in the non-LBBAP DDD-CLS group but decreased in the DDD group (P\u0026lt;0.001). Atrial arrhythmia burden was similar across pacing modes and lead locations, except for a higher burden in the non-LBBAP DDD-CLS group compared with non-LBBAP DDD.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eIn this large real-world cohort, CLS maintained stable physiological rate adaptation across pacing modes and lead locations. Minor differences in ventricular rate and thoracic impedance were observed, but overall CLS performance was consistent between LBBAP and non-LBBAP configurations, supporting its use in conduction system pacing.\u003c/p\u003e","manuscriptTitle":"Efficacy of Closed Loop Stimulation in Left Bundle Branch Area Pacing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-20 16:48:33","doi":"10.21203/rs.3.rs-8897052/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"1a9f539d-b155-4091-be49-611e529f8325","owner":[],"postedDate":"February 20th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-13T00:23:59+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-20 16:48:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8897052","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8897052","identity":"rs-8897052","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}