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Aim: To evaluate whether left bundle branch block with residual conduction (rLBBB) is associated with worse outcomes after cardiac resynchronisation therapy (CRT). Methods: All consecutive CRT implants at our institution between 2006 and 2013 were identified from our local device registry. Pre- and post-implant patient specific data were extracted from clinical records. Results: A total of 690 CRT implants were identified during the study period. Prior to CRT, 52.2% of patients had true left bundle branch block (LBBB), 19.1% a pacing-induced LBBB (pLBBB), 11.2% a rLBBB, 0.8% a right bundle branch block (RBBB), and 16.5% had a nonspecific intraventricular conduction delay (IVCD) electrocardiogram pattern. Mean age at implant was 67.5 years (standard deviation [SD] = 10.6), mean left ventricular ejection fraction (LV EF) was 25.7% (SD = 7.9%), and mean QRS duration was 158.4 ms (SD = 32 ms). After CRT, QRS duration was significantly reduced in the LBBB (p

Abstract Background The inSighT study was designed to determine the prevalence of ischemic changes as recorded by implantable cardioverter–defibrillator (ICD) ST deviations in intracardiac electrocardiograms (EGM) over the 24 h preceding malignant ventricular arrhythmias (VT/VF). Methods The study enrolled patients with known coronary artery disease (CAD) or high risk of future development of CAD implanted with an ICD equipped with an ST monitoring feature (Ellipse™/Fortify Assura™, St. Jude Medical). Device session records were collected at each in‐clinic follow‐up. EGM ST levels of the beats over the 15 minutes prior to VT/VF events were compared using a t test with those from a baseline period of 23–24 h prior to the VT/VF event. All events with p

Summary: Background: Cardiac autonomic dysfunction after myocardial infarction identifies patients at high risk despite only moderately reduced left ventricular ejection fraction. We aimed to show that telemedical monitoring with implantable cardiac monitors in these patients can improve early detection of subclinical but prognostically relevant arrhythmic events. Methods: We did a prospective investigator-initiated, randomised, multicentre, open-label, diagnostic trial at 33 centres in Germany and Austria. Survivors of acute myocardial infarction with left ventricular ejection fraction of 36–50% had biosignal analysis for assessment of cardiac autonomic function. Patients with abnormal periodic repolarisation dynamics (≥5·75 deg2) or abnormal deceleration capacity (≤2·5 ms) were randomly assigned (1:1) to telemedical monitoring with implantable cardiac monitors or conventional follow-up. Primary endpoint was time to detection of serious arrhythmic events defined by atrial fibrillation 6 min or longer, atrioventricular block class IIb or higher and fast non-sustained (>187 beats per min; ≥40 beats) or sustained ventricular tachycardia or fibrillation. This study is registered with ClinicalTrials.gov, NCT02594488. Findings: Between May 12, 2016, and July 20, 2020, 1305 individuals were screened and 400 patients at high risk were randomly assigned (median age 64 years [IQR 57–73]); left ventricular ejection fraction 45% [40–48]) to telemedical monitoring with implantable cardiac monitors (implantable cardiac monitor group; n=201) or conventional follow-up (control group; n=199). During median follow-up of 21 months, serious arrhythmic events were detected in 60 (30%) patients of the implantable cardiac monitor group and 12 (6%) patients of the control group (hazard ratio 6·33 [IQR 3·40–11·78]; p

BackgroundThe REACT DX registry evaluates standard therapies to episodes of long-lasting atrial tachyarrhythmias and assesses the quality of sensing and stability of the lead and the implantable cardioverter-defibrillator (ICD) (BIOTRONIK Lumax VR-T DX and successors) over at least a 1-year follow-up period.ObjectiveTo study the association between the risk of de novo device-detected atrial fibrillation (AF), the autonomic perturbations before the onset of paroxysmal AF and a 7-days heart rate variability (7dHRV) 1 month after ICD implantation.MethodsThe registry consists of 234 patients implanted with an ICD, including 10 with de novo long-lasting atrial tachyarrhythmias with no prior history of AF. The patients were matched via the propensity-score methodology as well as for properties directly influencing the ECGs recorded using GE CardioMem CM 3000. Heart rate variability (HRV) analysis was performed using standard parameters from time- and frequency-domains, and from non-linear dynamics.ResultsNo linear HRV was associated with an increased risk of AF (p = n.s.). The only significant approach was derived from symbolic dynamics with the parameter “forbidden words” which distinguished both groups on all 7 days of measurements (p < 0.05), thereby quantifying the heart rate complexity (HRC) as drastically lower in the de novo AF group.ConclusionCardiac autonomic dysfunction denoted by low HRC may be associated with higher AF incidence. For patients with mild to moderate heart failure, standard HRV parameters are not appropriate to quantify cardiac autonomic perturbations before the onset of AF. Further studies are needed to determine the individual risk for AF that would enable interventions to restore autonomic balance in the general population.

Many patients receiving cardiac resynchronization therapy (CRT) suffer from permanent atrial fibrillation (AF). Knowledge of the atrial rhythm is important to direct pharmacological or interventional treatment as well as maintaining AV-synchronous biventricular pacing if sinus rhythm can be restored. A single pass single-coil defibrillator lead with a floating atrial bipole has been shown to obtain reliable information about the atrial rhythm but has never been employed in a CRT-system. The purpose of this study was to assess the feasibility of implanting a single coil right ventricular ICD lead with a floating atrial bipole and the signal quality of atrial electrograms (AEGM) in CRT-defibrillator recipients with permanent AF. Methods and results: Seventeen patients (16 males, mean age 73 ± 6 years, mean EF 25 ± 5%) with permanent AF and an indication for CRT-defibrillator placement were implanted with a designated CRT-D system comprising a single pass defibrillator lead with a atrial floating bipole. They were followed-up for 103 ± 22 days using remote monitoring for AEGM transmission. All patients had at last one AEGM suitable for atrial rhythm diagnosis and of 100 AEGM 99% were suitable for visual atrial rhythm assessment. Four patients were discharged in sinus rhythm and one reverted to AF during follow-up. Conclusion: Atrial electrograms retrieved from a single-pass defibrillator lead with a floating atrial bipole can be reliably used for atrial rhythm diagnosis in CRT recipients with permanent AF. Hence, a single pass ventricular defibrillator lead with a floating bipole can be considered in this population. Keywords: Cardiac resynchronization therapy, Heart failure, Atrial fibrillation, Remote monitoring, Atrial sensing, Defibrillator

The use of cardiac implantable electronic devices (CIED) has risen steadily, yet the rate of cardiac device infections (CDI) has disproportionately increased. Amongst all cardiac device infections, the pocket infection is the most challenging diagnosis. Therefore, we aimed to improve diagnosis of such pocket infection by identifying relevant biomarkers.We enrolled 25 consecutive patients with invasively and microbiologically confirmed pocket infection. None of the patients had any confounding conditions. Pre-operative levels of 14 biomarkers were compared in infected and control (n = 50) patients. Our selected biomarkers included white blood cell count (WBC), C-reactive protein (CRP), procalcitonin (PCT), lipopolysaccharide binding protein, high-sensitivity C-reactive protein (HS-CRP), polymorphonuclear-elastase, presepsin, various interleukins, tumor necrosis factor α (TNF-α), and granulocyte macrophage colony-stimulating factor (GM-CSF).Of the 25 patients with isolated pocket infection (70±13years, 76% male, 40% ICDs), none presented with leukocytosis. In contrast, they had higher serum levels of HS-CRP (p = 0.019) and PCT (p = 0.010) than control patients. Median PCT-level was 0.06 ng/mL (IQR 0.03-0.07 ng/mL) in the study group versus 0.03 ng/mL (IQR 0.02-0.04 ng/mL) in controls. An optimized PCT cut-off value of 0.05 ng/mL suggests pocket infection with a sensitivity of 60% and specificity of 82%. In addition TNF-α- and GM-CSF-levels were lower in the study group. Other biomarkers did not differ between groups.Diagnosis of isolated pocket infections requires clinical awareness, physical examination, evaluation of blood cultures and echocardiography assessment. Nevertheless, measurement of PCT- and HS-CRP-levels can aid diagnosis. However, no conclusion can be drawn from normal WBC-values.clinicaltrials.gov identifier: NCT01619267.

The placement of an implantable cardioverter defibrillator (ICD) has become routine practice to protect high risk patients from sudden cardiac death. However, implantation-related myocardial micro-damage and its relation to different implantation strategies are poorly characterized.A total of 194 ICD recipients (64±12 years, 83% male, 95% primary prevention of sudden cardiac death, 35% cardiac resynchronization therapy) were randomly assigned to one of three implantation strategies: (1) ICD implantation without any defibrillation threshold (DFT) testing, (2) estimation of the DFT without arrhythmia induction (modified "upper limit of vulnerability (ULV) testing") or (3) traditional safety margin testing including ventricular arrhythmia induction. High-sensitive Troponin T (hsTnT) levels were determined prior to the implantation and 6 hours after.All three groups showed a postoperative increase of hsTnT. The mean delta was 0.031±0.032 ng/ml for patients without DFT testing, 0.080±0.067 ng/ml for the modified ULV-testing and 0.064±0.056 ng/ml for patients with traditional safety margin testing. Delta hsTnT was significantly larger in both of the groups with intraoperative ICD testing compared to the non-testing strategy (p≤0.001 each). There was no statistical difference in delta hsTnT between the two groups with intraoperative ICD testing (p = 0.179).High-sensitive Troponin T release during ICD implantation is significantly higher in patients with intraoperative ICD testing using shock applications compared to those without testing. Shock applications, with or without arrhythmia induction, did not result in a significantly different delta hsTnT. Hence, the ICD shock itself and not ventricular fibrillation seems to cause myocardial micro-damage.ClinicalTrials.gov NCT01230086.

BACKGROUND: Post-implantation therapies to optimize cardiac resynchronization therapy (CRT) focus on adjustments of the atrio-ventricular (AV) delay and ventricular-to-ventricular (VV) interval. However, there is little consensus on how to achieve best resynchronization with these parameters. The aim of this study was to examine a novel combination of doppler echocardiography (DE) and three-dimensional echocardiography (3DE) for individualized optimization of device based AV delays and VV intervals compared to empiric programming. METHODS: 25 recipients of CRT (male: 56%, mean age: 67 years) were included in this study. Ejection fraction (EF), the primary outcome parameter, and left ventricular (LV) dimensions were evaluated by 3DE before CRT (baseline), after AV delay optimization while pacing the ventricles simultaneously (empiric VV interval programming) and after individualized VV interval optimization. For AV delay optimization aortic velocity time integral (AoVTI) was examined in eight different AV delays, and the AV delay with the highest AoVTI was programmed. For individualized VV interval optimization 3DE full-volume datasets of the left ventricle were obtained and analyzed to derive a systolic dyssynchrony index (SDI), calculated from the dispersion of time to minimal regional volume for all 16 LV segments. Consecutively, SDI was evaluated in six different VV intervals (including LV or right ventricular preactivation), and the VV interval with the lowest SDI was programmed (individualized optimization). RESULTS: EF increased from baseline 23±7% to 30±8 (p

The AVOID-FFS (Avoidance of Far-Field R-wave Sensing) study aimed to investigate whether an atrial lead with a very short tip-to-ring spacing without optimization of pacemaker settings shows equally low incidence of far-field R-wave sensing (FFS) when compared to a conventional atrial lead in combination with optimization of the programming.Patients receiving a dual chamber pacemaker were randomly assigned to receive an atrial lead with a tip-to-ring spacing of 1.1 mm or a lead with a conventional tip-to-ring spacing of 10 mm. Postventricular atrial blanking (PVAB) was programmed to the shortest possible value of 60 ms in the study group, and to an individually determined optimized value in the control group. Atrial sensing threshold was programmed to 0.3 mV in both groups. False positive mode switch caused by FFS was evaluated at one and three months post implantation.A total of 204 patients (121 male; age 73±10 years) were included in the study. False positive mode switch caused by FFS was detected in one (1%) patient of the study group and two (2%) patients of the control group (p = 0.62).The use of an atrial electrode with a very short tip-to-ring spacing avoids inappropriate mode switch caused by FFS without the need for individual PVAB optimization.ClinicalTrials.gov NCT00512915.

Aims Cardiac resynchronization therapy (CRT) via biventricular (BIV) pacing is indicated in patients with heart failure (HF), reduced ejection fraction, and prolonged QRS duration. Quadripolar leads and multipoint pacing (MPP) allow multiple left ventricle (LV) sites pacing. We aimed to assess the clinical benefit of MPP in patients who do not respond to standard BIV pacing. Methods and results Overall, 3724 patients were treated with standard BIV pacing. After 6 months, 1639 patients were considered as CRT non-responders (echo-measured relative reduction in LV end-systolic volume (LVESV) < 15%) and randomized to MPP or BIV. We analysed 593 randomized patients (291 MPP, 302 BIV), who had BIV pacing >97% of the time before randomization and complete 12 months of clinical and echocardiographic data. The endpoint composed of freedom from cardiac death and HF hospitalizations and by LVESV relative reduction ≥15% between randomization and 12 months occurred more frequently in MPP [96/291 (33.0%)] vs. BIV [71/302 (23.5%), P = 0.0103], which was also confirmed at multivariate analysis (hazard ratio = 1.55, 95% confidence interval = 1.02–2.34, P = 0.0402 vs. BIV). HF hospitalizations occurred less frequently in MPP [14/291 (4.81%)] vs. BIV [29/302 (9.60%), incidence rate ratio = 50%, P = 0.0245]. Selecting patients with a large (>30 ms) dispersion of interventricular electrical delay among the four LV lead dipoles, reverse remodelling was more frequent in MPP [18/51 (35.3%)] vs. BIV [11/62 (17.7%), P = 0.0335]. Conclusion In patients who do not respond to standard CRT despite the high BIV pacing percentage, MPP is associated with lower occurrence of HF hospitalizations and higher probability of reverse LV remodelling compared with BIV pacing. [ABSTRACT FROM AUTHOR]

Abstract   The implantation of a pacemaker is the therapy of choice for symptomatic bradyarrhythmias. The perioperative complication rate is low. This article gives an overview on possible complications, their avoidance and treatment. [ABSTRACT FROM AUTHOR]

Introduction and aims of the study: Atrial oversensing may trigger false positive mode switch to an asynchronous mode in dual chamber pacemakers. While myopotential oversensing and far-field R wave sensing within the postventricular atrial refractory period are well characterized, data about oversensing (near-field P wave or far-field R wave) within the atrioventricular delay is limited. Aim of the study was to determine the incidence of preventricular oversensing in the atrial channel of current dual chamber pacemakers.Methods: Consecutive patients with dual chamber pacemakers who were in sinus rhythm and who showed no myopotential oversensing were included in the study. Atrial sensitivity was programmed to the maximal available value and atrioventricular delay was prolonged when necessary for intrinsic atrioventricular conduction.Results: Ten out of 100 (10%) patients showed oversensing within the atrioventricular delay at highest levels of atrial sensitivity, median sensing threshold for the signals was 0.35 mV, and the median coupling interval between preventricular atrial oversensing and the ventricular sensed event was 20 ms.Conclusion: The incidence of inappropriate mode switch caused by atrial preventricular oversensing related to near-field P wave or far-field R wave oversensing in dual chamber pacemakers is up to 10%. Interpretation of pacemaker Holters should consider oversensing within the atrioventricular delay as a differential diagnosis to true episodes of atrial tachyarrhythmias. [ABSTRACT FROM AUTHOR]

Aims: Cardiac resynchronization therapy (CRT) via biventricular (BIV) pacing is indicated in patients with heart failure (HF), reduced ejection fraction, and prolonged QRS duration. Quadripolar leads and multipoint pacing (MPP) allow multiple left ventricle (LV) sites pacing. We aimed to assess the clinical benefit of MPP in patients who do not respond to standard BIV pacing., Methods and Results: Overall, 3724 patients were treated with standard BIV pacing. After 6 months, 1639 patients were considered as CRT non-responders (echo-measured relative reduction in LV end-systolic volume (LVESV) < 15%) and randomized to MPP or BIV. We analysed 593 randomized patients (291 MPP, 302 BIV), who had BIV pacing >97% of the time before randomization and complete 12 months of clinical and echocardiographic data. The endpoint composed of freedom from cardiac death and HF hospitalizations and by LVESV relative reduction ≥15% between randomization and 12 months occurred more frequently in MPP [96/291 (33.0%)] vs. BIV [71/302 (23.5%), P = 0.0103], which was also confirmed at multivariate analysis (hazard ratio = 1.55, 95% confidence interval = 1.02-2.34, P = 0.0402 vs. BIV). HF hospitalizations occurred less frequently in MPP [14/291 (4.81%)] vs. BIV [29/302 (9.60%), incidence rate ratio = 50%, P = 0.0245]. Selecting patients with a large (>30 ms) dispersion of interventricular electrical delay among the four LV lead dipoles, reverse remodelling was more frequent in MPP [18/51 (35.3%)] vs. BIV [11/62 (17.7%), P = 0.0335]., Conclusion: In patients who do not respond to standard CRT despite the high BIV pacing percentage, MPP is associated with lower occurrence of HF hospitalizations and higher probability of reverse LV remodelling compared with BIV pacing., Competing Interests: Conflict of interest: Dr Rinaldi has received research funding and/or consultation fees from Abbott, Medtronic, Boston Scientific, Spectranetics, EBR Systems, and MicroPort outside of the submitted work. Dr Leclercq has received honoraria from Abbott, Medtronic, Boston Scientific, Biotronik, and Livanova. Dr Burri has received institutional fellowship support and research grants from Abbott. Dr Sperzel serves as a consultant to Abbott, in addition to receiving honoraria and currently conducting research sponsored by Abbott. Dr Thibault has received research support and honoraria from Abbott and Medtronic. Dr Lee, Ms Lin. and Mr Grammatico are employees of Abbott. All remaining authors have declared no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)