bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiac defibrillator implantation in patients with syncope and inducible ventricular arrhythmia: insights from the German DEVICE registry
Authors: Kahle A K , Senges J , Hochadel M , Brachmann J , Thomas D , Straube F , Bonaventura K , Vom Dahl J , Werner N , Butter C , Scherschel K , Meyer C 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Programmed ventricular stimulation may be considered for risk stratification of sudden cardiac death. The history of syncope is an independent predictor for appropriate device discharge and sudden cardiac death, but data remain sparse among different populations.

Purpose
The aim of this study was to assess the prognostic value of previous syncope and inducible ventricular arrhythmia (VA) during programmed stimulation in patients undergoing defibrillator implantation.

Methods
Among 4,196 patients enrolled in the prospective, multi-centre German DEVICE Registry undergoing defibrillator implantation, patients with syncope and inducible VA (n=285, 6.8%) vs. those with a secondary preventive indication (n=1,885, 45.2%) serving as a control group were studied. In an additional analysis of patients with inducible VA, those with vs. without (n=86, 2.1%) previous syncope were compared.

Results
Patients with syncope and inducible VA (64.9±14.4 years, 81.1% male) presented less often with congestive heart failure (15.1% vs. 29.1%; P&lt;0.001) and any underlying structural heart disease (84.9% vs. 89.3%; P=0.030) with a higher left ventricular ejection fraction (43.7±14.2% vs. 38.1±14.2%; P&lt;0.001) than patients with a secondary preventive indication (65.0±13.8 years, 81.0% male). Whereas dilated cardiomyopathy (16.8% vs. 23.8%; P=0.009) was less common in patients with syncope and inducible VA, hypertrophic cardiomyopathy (5.6% vs. 2.8%; P=0.010) and Brugada syndrome (2.1% vs. 0.3%; P&lt;0.001) were found more frequently. Device implantation was performed more often urgently in patients with syncope and inducible VA (46.4% vs. 22.5%; P=0.005). During 1 year of follow-up, mortality (5.1% vs. 8.9%; P=0.036) and the rate of major adverse cardiac or cerebrovascular events (5.8% vs. 10.0%; P=0.027) were lower in patients with previous syncope and inducible VA compared to patients with a secondary preventive indication. Among patients with inducible VA, post-procedural adverse events including rehospitalization (27.6% vs. 21.7%; P=0.37), defibrillator shocks (16.0% vs. 15.0%; P=0.85) and recurrent syncope (3.0% vs. 0%; P=0.32) did not differ between those with vs. without syncope.

Conclusions
Patients with a history of syncope and inducible VA present less frequently with most cardiac comorbidities resulting in better outcomes following defibrillator implantation than patients with a secondary preventive indication. Nevertheless, patients with inducible VA experience a relevant number of post-procedural adverse events not differing between those with vs. without syncope, which underlines the importance of VA inducibility, potentially irrespective of the history of syncope.
Repolarization changes following conduction system pacing evaluated by ultra-high-frequency electrocardiography
Authors: Nguyen U , Curila K , Halamek J , Vernooy K , Palacios S , Vesela J , Prinzen F W , Jurak P 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public hospital(s). Main funding source(s): This work was supported by the National Institute for Research of Metabolic and Cardiovascular Diseases project (Programme EXCELES, ID Project No. LX22NPO5104) — Funded by the European Union — Next Generation EU and a personal grant from the Dutch Heart Foundation (2021T016).

Background
On the surface electrogram (ECG) of a normal heart, the polarity of the T-wave is concordant with the QRS complex. This phenomenon could be explained by the presumption that regions that depolarize first repolarize last. Acute changes in ventricular activation can lead to abnormal T-waves. Conduction system pacing (CSP) leads to a more physiological ventricular activation compared to conventional right ventricular pacing (RVP), but little is known about repolarization changes following CSP.

Purpose
To compare repolarization changes following CSP with those during RVP and normal intrinsic activation in patients requiring bradycardia treatment.

Methods
Ultra-high-frequency electrocardiographic (UHF-ECG) measurements were acquired at time of implantation during normal intrinsic rhythm (narrow QRS [nQRS], n=199), selective His bundle pacing (sHBP, n=50), left ventricular septal pacing (LVsp, n=87), non-selective left bundle branch pacing (nsLBBP, n=47), and RVP (n=102). Activation and repolarization times were calculated for leads V1 and V6 from the time position of the QRS negative and from the T-wave positive derivative maxima respectively. Dyssynchrony (e-DYS) was defined as the time difference between leads V6 and V1. Differences between e-DYS depolarization (e-DYS-dpt) and repolarization (e-DYS-rpt) was evaluated by Kruskal Wallis tests.

Results
The left panel of Figure 1 demonstrates that during both nQRS and sHBP, e-DYS-dpt is small and slightly positive, while e-DYS-rpt is negative. RVP leads to a positive and increased e-DYS-dpt and e-DYS-rpt. LVsp and nsLBBP create negative e-DYS-dpt and e-DYS-rpt values. e-DYS-dpt and e-DYS-rpt was significant different between the groups (p-values &lt;0.001). The middle and right panel of Figure 1 shows that during nQRS and sHBP, the activation-repolarization relationship is negative (~ first depolarized regions repolarize last). RVP, LVsp, and nsLBBP leads to a positive activation-repolarization relationship (~ first depolarized regions repolarize first).

Conclusion
sHBP preserves the physiological negative activation-repolarization relationship. RVP, LVsp, and nsLBBP reverses the activation-repolarization relationship, though smallest changes are present during LVsp. LVsp (after nQRS and sHBP) leads to the most synchronous activation and repolarization of the three.
Ventricular pacing burden in patients with left bundle branch block after transcatheter aortic valve replacement therapy
Authors: Serban T , Knecht S , Du Fay De Lavallaz J , Nestelberger T , Kaiser C , Leibundgut G , Schaer B , Krisai P , Osswald S , Sticherling C , Kuehne M , Badertscher P 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Electrophysiological (EP) testing has been proposed in the latest ESC guidelines for cardiac pacing to identify LBBB patients with infrahisian conduction delay (IHCD) after transcatheter aortic valve replacement (TAVR). While in general IHCD is defined by a His-ventricular (HV) interval of &gt; 55ms, a cut-off of ≥ 70ms to trigger pacemaker (PM) implantation has been proposed in the latest ESC guidelines. The ventricular pacing (VP) burden during follow-up in such patients is largely unknown.

Purpose
To assess the VP burden during follow-up of patients receiving PM therapy for LBBB after TAVR based on an HV interval &gt; 55 ms and ≥ 70ms.

Methods
All patients with new-onset or pre-existing LBBB after undergoing TAVR at a tertiary referral center underwent EP testing the day after TAVR. In patients with a prolonged HV interval (&gt;55 ms), PM implantation was performed by a trained electrophysiologist in a standardized fashion. All devices were programmed to avoid unnecessary VP by specific algorithms (e.g., AAI-DDD).

Results
701 patients underwent TAVR at our university hospital between October 2014 and November 2021. 177 patients presented with new-onset or pre-existing LBBB the day following TAVR and underwent EP testing. An HV interval &gt; 55 ms was found in 58 patients (33%) and an HV interval ≥ 70 ms in 21 patients (12%).
51 patients (mean age 84 ± 6.2 years, 45% women) agreed to receive a PM, out of which 20 (39%) patients had an HV Interval over 70 ms. Atrial fibrillation was present in 53% of the patients. A dual chamber PM was implanted in 39 (77%), and a single chamber pacemaker in 12 (23%) patients, respectively. Median FU was 21 months (IQR 11-41).
The median VP burden overall was 3%. The median VP burden was numerically higher in patients with an HV ≥70 ms (6.5% [0.8 - 52]) than in those with an HV between 55 and 69 ms (2% [0 – 17], p = 0.23). 31% of patients had a VP burden &lt;1%, 27% 1-5% and 41% &gt; 5% (Figure). The median HV intervals in patients with VP burden &lt;1%, 1-5% and &gt;5% were 66 (IQR 62 -70) ms, 66 (IQR 63 – 74) ms and 68 (IQR 60 – 72) ms respectively, p= 0.52. When only assessing patients with an HV interval 55-69 ms, 36% demonstrated a VP burden of &lt;1%, 29% of 1-5% and 35% of &gt;5 %. In patients with an HV Interval ≥ 70ms, 25% demonstrated a VP burden &lt;1%, 25% of 1-5% and 50% of &gt;5 %, p=0.64 (Table).

Conclusion
VP burden can be significant in patients with LBBB after TAVR and an HV interval of &gt; 55 ms. Further studies are warranted to define the optimal cut-off to trigger PM implantation in patients with LBBB after TAVR.
His bundle pacing: 10-years follow-up
Authors: Marcantoni L , Deluca F , Pastore G , Baracca E , Marsiglia S , Fornasaro M , Cappato E , Pigaiani C , Manzato E , Tiribello A , Raffagnato P , Zanon F 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
His bundle pacing (HBP) ensures a physiologic ventricular activation and can prevent pacing-induced cardiomyopathy. Published experiences confirm good clinical results on short-term follow-up. Data on long-term follow-up are still lacking

Objective
analyze clinical and technical results of HBP in an unselected population during a very long-term follow-up.

Methods
We retrospectively analyzed 370 patients (mean age 75±8 years; 221 males) with standard indication for pacing implanted with HBP from 2003 to 2012. In all cases the HBP implant was performed by lumenless fixed screw 3830 Medtronic and deflectable sheath C304. In 52% cases selective-HBP was obtained while 48% was non selective-HBP. The indications for pacing were AV block in 51%, sinus node disease in 22%, atrial fibrillation with slow ventricular rate in 25%, heart failure in 2%. Ischemic cardiopathy was found in 84 patients (29%); hypertension in 317 patients (86%) and diabetes in 108 patients (29%). Pre-implant QRS duration was 119±30 ms and basal mean EF 57±11%. The Hisian lead was inserted in ventricular port of a CRT-P device in 162 (44%) patients, in the atrial port of a DR device in 183 (49%) patients, and in the only channel of a SR device in 25 (7%) patients. A back-up standard lead was implanted in right ventricular apex or septum in 203 (55%) patients.

Results
All patients were followed by ambulatory check once a year. 124 (34%) patients reached 10 years follow-up (mean 12.3 ±1.8 years). At the end of follow-up, the mean EF was 61±8% (P=NS) and the mean paced QRS duration 123 ± 27 (P=NS). 10 (8%) patients had heart failure hospitalizations. 26 (21%) died after a mean of 12.1 ±1.7 years. From a technical point of view, 99 (80%) patients showed a good performance of the HBP lead at the last follow-up while 25 (20%) patients experienced lead-related problems: 20 (16%) had issues related to HBP lead (2 cases of severe HBP malfunction required hospitalization due to syncope) and 5 (4%) had malfunction of the back-up lead. The mean longevity of the devices was 6.6 ±2.6 years and each patient had 1.5 ±0.8 replacements. It was required to add a back up catheter in 3.6% of patients. The remaining 205 patients completed a mean follow-up of 6.3±2.7 years while 41(11%) patients were lost at follow-up (died within the first month post-implant or checked in other centres).

Conclusion
HBP is safe and feasible in the clinical practice. The system maintains a good performance during a long-term follow-up and ensures a physiologic ventricular contraction thus allowing good clinical outcome. The EF and QRS duration remain in normal values.
Stylet-driven vs. non-stylet-driven lead implantation for left bundle branch area pacing
Authors: Haeberlin A , Seiler J , Kozhuharov N , Baldinger S H , Servatius H , Madaffari A , Thalmann G , Kueffer T , Muehl A , Tanner H , Roten L , Reichlin T , Noti F 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left bundle branch area pacing (LBBAP) is a novel pacing strategy, which overcomes limitations of right ventricular pacing. Conventional stylet-driven and non-stylet-driven leads have been used as a conduction system pacing lead. Procedural outcome data comparing both lead types are, however, scarce.

Purpose
To compare procedural outcomes during CSP device implantation with respect to the use of stylet-driven vs. non-stylet-driven leads.

Methods
We prospectively assessed 170 consecutive LBBAP lead implantation attempts at our center from 09/2021 to 11/2022. All implanters had previous experience with His-bundle pacing lead implantation using the non-stylet-driven lead and 91% of all systems were implanted by two high-volume device implanters. Successful conduction system pacing was established according to standard criteria (LBBAP: R-wave peak time in V6, V1-V6-interpeak interval, programmed stimulation or visibility of a left bundle potential) and pacing thresholds (&lt;2V/0.5ms). The used leads in this analysis were the non-stylet-driven 3830 SelectSure lead (Medtronic, US) and the stylet-driven Solia (Biotronik, Germany), Ingevity+ (Boston Scientific, US) and Tendril STS (Abbott, US) lead. Patient selection and implantation strategy was at the operator’s discretion.

Results
Clinical baseline characteristics, echocardiography/ECG data and indications did not differ between patients, who received a stylet-driven or non-stylet-driven lead (table showing percentages and median values/interquartile ranges). Patients underwent implantation of a non-stylet driven 3830 SelectSure lead in 20% of cases and a stylet-driven lead in 80% of cases (Solia 76%, Ingevity+ 3%, Tendril STS 1%). Electrical outcome data did not differ between lead types. However, procedural success rate was significantly higher using stylet-driven leads (p=0.025) and a trend towards shorter overall intervention duration was observed as well (p=0.1).

Conclusion
Stylet-driven leads offer higher LBBAP lead implantation success rates while shortening implant duration.
Acute procedural outcomes of left bundle branch area pacing compared to His-bundle pacing
Authors: Haeberlin A , Seiler J , Kozhuharov N , Baldinger S H , Servatius H , Madaffari A , Thalmann G , Kueffer T , Muehl A , Tanner H , Roten L , Reichlin T , Noti F 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Conduction system pacing (CSP), encompassing left bundle branch area pacing (LBBAP) and His-bundle pacing (HBP), is a novel pacing strategy, which overcomes limitations of conventional right ventricular pacing. Feasibility and early safety of both strategies have been established previously. While HBP is mentioned as an alternative pacing strategy in the latest European and American pacing guidelines, implantation recommendations regarding LBBAP are scarce. Notably, HBP was described to be associated with a significantly higher procedural failure rate compared to LBBAP, making it potentially more contestable.

Purpose
To compare procedural outcomes after HBP and LBBAP lead implantation.

Methods
We prospectively assessed 303 consecutive CSP lead implantation attempts at our center from 08/2018 to 11/2022. 81% of all implantations were performed by two high-volume device implanters. Successful conduction system pacing was established according to standard criteria (HBP: QRS morphology, R-wave peak time in V6, programmed stimulation, visibility of a His potential; LBBAP: R-wave peak time in V6, V1-V6-interpeak interval, programmed stimulation or visibility of a left bundle potential) and pacing thresholds (HBP: &lt;4.0V/1.0ms; LBBAP: &lt;2V/0.5ms). Patient selection and the implantation strategy used was at the operator’s discretion.

Results
Patients with a HBP attempt were younger and had a narrower QRS complex but did not differ with respect to left or right ventricular function and dimension (table showing percentages and median values/interquartile ranges). LBBAP systems were more often implanted in lieu of CRT, whereas HBP systems were more commonly used in case of AV block without heart failure (table). Acute procedural success rate, overall procedure duration and fluoroscopy time were significantly better during LBBAP implantations (all p&lt;0.001). Success rates, sensing values and capture thresholds (@1ms for HBP and @0.5ms for LBBAP) were superior in LBBAP systems, while achieved paced QRS duration was slightly shorter in HBP systems (table, figure 1).

Conclusion
Success rates and acute procedural outcomes favor implantation of LBBAP compared to HBP systems.
Left bundle branch area pacing guided by electroanatomical mapping in patients with structural heart disease and advanced conduction abnormalities
Authors: Richter S , Ebert M , Gebauer R , Lucas J , Moscoso-Luduena C , Paetsch I , Hindricks G , Doering M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left bundle branch area pacing (LBBAP) can be technically challenging and fluoroscopy-intense, particularly in patients with structural heart disease (SHD) and advanced conduction abnormalities. Three-dimensional electroanatomical mapping (EAM) facilitates high-resolution, real-time, and non-fluoroscopic lead navigation, electrogram and pace mapping.

Purpose
The purpose of the study was to prospectively evaluate the feasibility, safety, and outcomes of routine EAM-guided LBBAP in patients with SHD and advanced conduction abnormalities.

Methods
Consecutive patients with SHD and advanced conduction abnormalities (defined as second or third-degree atrioventricular (AV) block and/or complete bundle branch block) who underwent an attempt at EAM-guided LBBAP were included. EAM-guided lead implantation was performed in all patients following a standardized protocol irrespective of the pacing indication and type of conduction disturbance. The feasibility, safety, procedural and mid-term outcomes were evaluated. Electrical, echocardiographic, and clinical parameters were assessed at implantation and last follow-up.

Results
Thirty-two patients (68±18 years; 19% female) were included. The indication for pacing was cardiac resynchronization therapy in 50%, AV block in 44%, and pace-and-ablate in 6% of patients; 24 patients (75%) had an intrinsic QRS &gt;150 ms, 17 (53%) had LBBB. Primary EAM-guided LBBAP was successful in 29 patients (91%). Procedural duration was 95 (70-110) min, total fluoroscopy time 0.93 (0.40-1.73) min, and total fluoroscopy dose 35.4 (20.5-77.2) cGycm2 (Figure 1A). The paced QRS duration during LBBAP was significantly shorter than the baseline intrinsic QRS duration (121.9±10.7 vs. 159.2±34.4 ms; p&lt;0.001) (Figure 1B) and remained stable (120.3±11.1 ms; p=0.370) during a mean follow-up of 7.0±5.9 (median 5.4 [IQR 2.1-12.6]) months. LBBAP capture threshold was 0.57±0.23V/0.4ms at implantation and remained low during follow-up (0.58±0.18V/0.5±0.2ms; p=0.877). There was no increase in LBBAP capture threshold &gt;1.0V/0.4 ms during follow-up. Overall LVEF improved significantly from 44.2±14.3% at baseline to 49.4±13.1% at last follow-up (p=0.009), NYHA functional class from 2.4±0.6 to 1.8±0.6 (p=0.002), respectively (Figure 1C+D). No complications occurred that required intervention.

Conclusion
Routine near-zero fluoroscopy EAM-guided LBBAP can safely be performed in patients with SHD and advanced conduction abnormalities with high success rates and favourable mid-term outcomes. Further studies are needed to investigate whether the use of EAM improves overall outcome of conduction system pacing, and to identify specific patient populations who benefit the most from EAM-guided lead implantation.
A leadless ventricular pacemaker providing atrioventricular synchronous pacing in the real-world setting: acute results from the Micra AV post-approval registry
Authors: Clementy N , Chinitz J , Marijon E , Haeberlin A , Winter S , Iacopino S , Curnis A , Breitenstein A , Hussin A , Mela T , El-Chami M , Roberts P R , Piccini J P , Stromberg K , Garweg C 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Medtronic, inc.

Introduction
Advances in leadless pacemaker technology have enabled accelerometer based atrioventricular synchronous (AVS) pacing by sensing atrial mechanical contraction. However, acute safety performance of these devices in real-world clinical practice has not been assessed.

Objectives
To report the acute performance of the Micra AV transcatheter pacemaker from the worldwide Micra AV post-approval registry (PAR).

Methods
The Micra AV PAR is an ongoing prospective single-arm observational study designed to assess the safety and effectiveness of the Micra AV system in the real-world setting. Patients enrolled in the Micra AV PAR will be followed for 3 years. For the present interim analysis, baseline characteristics, total AV synchrony index (sum of %AM-VP, %AM-VS, and AV conduction mode switch percentage), and major complications occurring within 30-days of implant were summarized and compared to a historical cohort of 2,667 transvenous dual chamber (TV-DC) pacing patients.

Results
The device was successfully implanted in 797 of 802 patients (99.4%) at 99 centers. Mean age was 74.1±15.1 years and 42.3% were female. The most common pacing indication was AV block (55.7%). Comorbidities included diabetes (29.7%), CAD (22.8%), and heart failure (12.1%), with 31.3% precluded from transvenous device therapy. Micra AV patients were on average older (74.1 vs. 71.1 yrs, P&lt;0.0001) and had a significantly higher incidence of renal disease (22.3% vs. 9.8%, P&lt;0.0001). Major complications occurred in 2.6% of Micra AV patients and in 7.1% TV-DC patients (P&lt;0.001, Figure). The reduction in major complications was largely driven by the absence of pneumothoraces and lead dislodgements among Micra AV patients. Of the 309 patients programmed to VDD mode with at least 30 days of device follow-up, the median AV synchrony index was 86.0% (IQR: 69.2% - 97.2%). Mean A4 amplitude was 2.1±1.6 m/s2 post-implant and 2.2±1.7 m/s2 at follow-up (P=0.57) in 308 patients with paired assessments.

Conclusions
The Micra AV leadless pacemaker was implanted with a high rate of success in patients with a high co-morbidity burden, with a significantly lower rate of acute complications relative to dual-chamber transvenous pacemakers despite patients being older and having a higher incidence of renal disease. Longer-term performance will continue to be assessed in this ongoing trial.