bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reasons for replacement and extraction of the subcutaneous implantable cardioverter-defibrillator in a large cohort
Authors: Van Der Stuijt W , Pepplinkhuizen S , Smeding L , Olde Nordkamp LRA , Wilde AAM , Knops RE 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The subcutaneous implantable cardioverter-defibrillator (S-ICD) is proven to be a safe and effective alternative to the transvenous ICD. However, battery longevity is estimated to be shorter in the S-ICD, although newer generations S-ICD are thought to have an increased battery longevity compared to the first generation. In addition, the S-ICD lacks the option for pacing therapy and may therefore be extracted in patients who later develop an indication for bradycardia pacing, antitachycardia pacing or resynchronization therapy. In this analysis, we aim to evaluate occurrence and reasons for S-ICD replacement and extraction.

Methods
In this retrospective analysis, we collected data on S-ICD generator replacement and extraction from consecutive patients who were implanted with an S-ICD in our tertiary center between February 2009 and December 2021.

Results
A total of 408 patients received an S-ICD, with a median follow-up duration of 4.0 (IQR 1.5-6.8) years. Of the 168 implanted first generation S-ICDs, 123 (73.2%) were replaced after a mean of 5.9 ± 0.8 years, all due to battery depletion. A second generation S-ICD was replaced in 2/40 (5%) patients and a third generation S-ICD in 11/200 patients (5.5%), after a mean of 4.8 ± 0.12 and 3.6 ± 1.6 years, respectively. Two third generation S-ICDs were replaced due to device malfunction, all other replacements (134/136, 98.5%) were due to battery depletion. The S-ICD was extracted in 38/408 (9.3%) patients. The mean time from initial implantation to extraction was 3.7 ± 2.5 years. Reasons for extraction were a newly developed indication for pacing or resynchronization therapy (N = 14), an expired indication for ICD therapy (N = 8), heart transplantation or implantation of left ventricular assist device (N = 4), repeated inappropriate shocks (N = 4), pocket infection (N = 3), pocket erosion (N = 2), lead defect (N = 1), Twiddler syndrome (N = 1) and patient preference (N = 1). A new S-ICD could be re-implanted in 7 patients (18.4%), a cardiac resynchronization therapy defibrillator was implanted in 7 patients (18.4%) and there was a need for a transvenous ICD in 10 patients (26.3%). The remaining 14 patients (36.8%) were not re-implanted with any type of ICD. Reasons for end of S-ICD therapy are presented in the figure.

Conclusion
In this large cohort, a battery longevity of the first generation S-ICD of 5.9 years was reached. After a median follow-up duration of 4.0 years, 17/408 patients received a transvenous device, due to the need for bradycardia or antitachycardia pacing or resynchronization therapy. Importantly, 14/408 patients underwent an S-ICD extraction and were not re-implanted with any type of ICD. These patients may especially benefit from S-ICD therapy, as this device is less complicated to extract compared to a transvenous ICD.
Leadless left bundle branch pacing: feasibility in an animal model
Authors: Vergara P , Taloni ST , Shute AS , Lee ML 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): EBR Systems Inc.

Introduction
Epicardial cardiac resynchronization therapy (CRT) is an established treatment for heart failure; left bundle branch (LBB) pacing has been proposed to overcome epicardial CRT limitations. In this study, we report on the first implants of a leadless electrode for endocardial pacing of the LBB in a porcine model.

Methods
The implant of the leadless, left ventricular endocardial pacing system (WiSE-CRT System) was attempted by transeptal approach in two porcines. Fluoroscopic and transoesophageal echocardiographic guidance were used to navigate the Delivery Sheath to the LBB area; the targeted implant site was selected by analysis of the electrograms from the implanting Electrode. At the end of the procedure, the animals were sacrificed and the hearts were isolated and analysed.

Results
In both animals, the Delivery System was successfully navigated to the LV septum. The target sites showed LBB electrograms preceding the far field ventricular electrogram by 15ms. The Electrode was successfully implanted on both animals with pacing threshold &lt;2.0V @ 0.5ms. The implant of the pacing electrode was associated with minimal, multifocal haemorrhage; Purkinje fibers components of the LBB were observed in the on both sides of the site of implantation site. The lesion was 1.7 mm large and 2 mm deep.

Conclusions
This study supports the feasibility of leadless LBB pacing. Anatomical evaluation showed a close relationship between the Electrode and the LBB, with absence of significant damage to the conduction system from the implanted Electrode.
Real-time image-guided lead placement in cardiac resynchronisation therapy: feasibility and outcome in a multicentre setting
Authors: Wouters PC , Van Slochteren FJ , Tuinenburg AE , Doevendans PAFM , Cramer MJM , Delnoy PPHM , Van Dijk VF , Meine M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Image-guidance to assist left ventricular (LV) lead placement may improve outcome after cardiac resynchronisation therapy (CRT). Because previous approaches and results varied greatly, the optimal strategy remains unknown. To date, only a few studies investigated ‘real-time’ guidance, and feasibility in a multicentre setting is lacking altogether.

Methods
In 30 patients from three hospitals, cardiac magnetic resonance imaging (MRI) was performed to identify myocardial scar and late mechanical activation (LMA). LMA was determined using radial strain, plotted over time. Segments without scar but clear LMA were classified as optimal, according to an accurate 36-segment model. LV-lead deployment was guided, in real-time, using live image-overlay with fluoroscopy. After 6 months, volumetric response was defined as ≥15% reduction in LV end-systolic volume (∆LVESV). Reduction in log-transformed N-terminal pro-brain natriuretic peptide (NT-proBNP) was assessed at 2 months.

Results
Real-time image-guidance was successful performed in all CRT patients (age 66±10 years; 59% male, 72% non-ischemic cardiomyopathy; 69% left bundle branch block). LV-leads were deployed as follows: within (24%), adjacent (52%), or remote (24%) from the pre-defined target. According to the traditional 18-segment model, a remote position occurred only once. On average, 86% of patients demonstrated a volumetric response (mean ∆LVESV 36±29%). In addition, lead placement was association with reduction in log-transformed NT-proBNP (Figure 1).

Conclusion
Real-time image-guidance towards a pre-defined target for LV-lead placement was feasible in a multicentre setting, and has promising clinical results. Efficacy will be further investigated in the randomised controlled ‘Advanced Image Supported Lead Placement in Cardiac Resynchronization Therapy’ trial.
Anatomical variations in coronary venous drainage: challenges and solutions in delivering cardiac resynchronisation therapy
Authors: Akhtar Z , Sohal M , Kontogiannis C , Leung LWM , Harding I , Zuberi Z , Bajpai A , Norman M , Pearse S , Beeton I , Gallagher MM 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Cardiac resynchronisation therapy (CRT) is the cornerstone of heart failure management. Delivery of a left ventricular lead can occur in a small proportion of patients undermining the benefits of this treatment. Abnormal coronary venous anatomy is a contributing factor to this failure. Although epicardial lead placement is available, this patient cohort requiring CRT is subject to higher peri-operative morbidity and mortality than the general population; a transvenous approach is preferable.

Purpose
To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties.

Methods
From 4 implanting institutes, data of all CRT implants between October 2008-October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted ‘normal’ anatomy. Patient demographics, procedural detail and subsequent left ventricle (LV) lead pacing indices were collected.

Results
From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2±10.6 years in age with a LV ejection fraction of 34±10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), 5 of which had coronary sinus ostium atresia (CSOA) including 2 with an ‘unroofed’ coronary sinus (CS); 1 patient had a unique anomalous origin of the CS and 1 patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anaesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull-through, including 1 case of endocardial LV implant. Pacing follow-up over 37.64±37.6 months demonstrated LV lead threshold between 0.62-2.9 volts (pulsewidth 0.4-1.5 milliseconds) in all cases; 5 patients died within 2.92±1.6 years of successful implant.

Conclusion
CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required.
The acute haemodynamic response with endocardial biventricular pacing: comparing RV paced and LBBB patients
Authors: Cantor E , Butcher C , Chow JJ , Sohaib S M A , Valli H , Shun-Shin M , Shi R , Boyalla V , O’connor M , Chen Z , Haldar S , Mason M , Lane R , Francis D , Wong T 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Background
A third of patients that receive cardiac resynchronisation (CRT) are non-responders. Predictors of positive response include broader QRS duration, non-ischaemic aetiology and sinus rhythm, but it is still unclear whether lead placement site determines a positive responder.

Purpose
We assessed the acute haemodynamic response of endocardial biventricular pacing in patients with intrinsic left bundle brunch block (LBBB) versus LBBB due to pre-existing right ventricular pacing (RVP).

Methods
Patients who fulfilled standard criteria for CRT implantation but had failed conventional (coronary sinus) left ventricular (LV) lead placement (primary or revision) or were deemed clinical ‘non-responders after &gt; 6 months of conventional CRT were enrolled. The acute haemodynamic response during endocardial biventricular pacing was assessed with a roving LV lead at 9 different locations (basal and mid: septal, anterior, posterior and lateral walls and apex). Acute changes in beat-to-beat systolic blood pressure (SBP) in the left ventricle were recorded and analysed.

Results
We recruited 23 patients across 10 UK centres: 14 intrinsic LBBB and 9 dependent on RVP. Patient characteristics were comparable: age (mean 67 + 10.6 years vs. 62 + 15.4 years), ischaemic (63% vs 50%), QRS (160 + 18ms vs. 190 + 36ms, p =0.07). Of the RVP group 5/9 had septal RV leads (the remainder apically positioned).
There was no difference in the SBP improvement between the groups: change in SBP ranged from -5.25 – 19.91mmHg (median 3mmHg) in RVP patients vs -5.92 – 23.03mmHg (median 3mmHg) for intrinsic LBBB. However, the improvement in SBP was more consistent across the different segments in the patients with RVP (group A), as compared to intrinsic LBBB (group B), where the lateral wall and then non-septal walls provided the greatest haemodynamic improvement.
Figure 1: depicts SBP improvement (in mmHg) during endocardial biventricular pacing in different positions within the LV for patients with RVP (A) vs underlying intrinsic LBBB (B): 9 segment model of the LV: Ant (anterior wall), Lat (lateral wall), Post (posterior wall), Sept (septum). Outer ring represents the four basal LV locations, middle ring the mid LV locations and centre ring the apex. Scale depicts mmHg improvement in SBP.

Conclusion
When implanting an LV lead for patients who are RV pacing dependent any position within the LV provides an acute haemodynamic improvement, compared with those with intrinsic LBBB, where a targeted lateral wall approach is more important. This finding corroborates the key differences in LV activation patterns for induced versus intrinsic LBBB.
Novel multi-site, multi-point biventricular pacing configuration: acute haemodynamic benefit
Authors: Kautzner J , Kukla J , Necasova L , Kryze L , Wunschova H , Sramko M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Supported by the research grant of the AZV (Ministry of Health of the Czech Republic)

Background
Biventricular pacing (BVP) using multiple left ventricular (LV) sites may augment the hemodynamic effect of cardiac resynchronisation therapy (CRT) by engaging a greater mass of the myocardium.

Purpose
To evaluate the acute hemodynamic effect of a novel multi-site, multi-point BVP configuration.

Methods
The study investigated 18 patients with idiopathic dilated cardiomyopathy and left bundle-branch block during implantation of a BVP device (age: 59 ± 14 years, female gender: 7 [39%], LVEF: 27 ± 6%, native QRS: 171 ± 16 ms). Conventional leads were placed in the right atrium (RA) and ventricle (RV), one quadripolar LV lead (Quartet, Abbott, Abbott Park, IL, USA) was positioned in the posterolateral and another one in lateral or anterolateral coronary vein. Individual bipoles of all leads were connected through a splitter to separate external cardiac stimulators. Hemodynamics was evaluated using a micromanometer-tipped catheter (Micro-Cath, Millar, Tx, USA) located in the LV during RA pacing above sinus rate and five atrio-ventricular sequential pacing configurations at the same rate: 1.) RA+RV, 2.) RA + RV + distal bipole of the LV lead with greater dP/dT („conventional BVP"), 3.) RA + RV + distal and proximal bipoles of the LV lead with greater dP/dT („single-lead multi-point BVP"), 4.) RA + RV + distal bipoles of both LV leads („two-lead multi-site BVP"), and 5.) sequentional pacing RA + RV + all bipoles of both LV leads interconnected to a mesh („maximum BVP").

Results
Compared to RA pacing, LV dP/dT was significantly greater during all BVP pacing configurations (RA pacing: 1940 ± 507 mmHg/s vs. conventional BVP: 2431 ± 855 mmHg/s, single-lead multi-point BVP: 2539 ± 740 mmHg/s, two-lead multisite BVP: 2517 ± 836 mmHg/s, and "maximum BVP": 2685 ± 893 mmHg/s, all p&lt;0.001, Figure 1), but not during RA-RV pacing (2014 ± 721 mmHg/s, p=0.12). In addition, dP/dT was significantly greater during "maximum BVP" compared to conventional BVP (p=0.05).

Conclusion
Compared to RA pacing and conventional BVP, the greatest increase in LV contractility was achieved with a novel multi-site, multi-point "maximum BVP" configuration. These preliminary findings provide a rationale for designing new approaches to CRT.
CTR-D without the left lead vs single/dual chamber ICD implantation: a cost saving strategy to avoid future upgrading of the latter?
Authors: Franco Fernandez I , Aroca Peinado A , Merino Llorens JL , Al-Razzo O 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.
Introduction/Background: Implantation of cardioverter defibrillators (ICD) to prevent sudden death is common in patients with left ventricular dysfunction (LVD) (1).However, these devices are expensive and there is increasing controversy about their cost benefit ratio. More agreement is present about the benefits of cardiac resynchronization therapy (CRT) in patients with LVD and concurrent heart failure (HF) and left bundle branch block (LBB) (2). Nevertheless, LVD often presents without one these two conditions which may only develop at follow up. This makes unclear the benefits of CRT at the time of ICD implantation (CRT-D) in these patients. Some have advocated implanting a CRT-D without the left ventricle lead instead of a conventional single/dual chamber ICD which would give the possibility to add CRT pacing without replacing the device generator at follow-up. However, this practice has been never evaluated and it is unclear its potential impact on cost.

Methods
This study included all CRT devices implanted in our institution since 2005. Patients with LVD but just heart failure (HF) or left bundle branch block (LBB) were considered for CRT-D implantation without the left lead. The number of patients who needed implantation of a LV lead at follow-up was analyzed. Only patients who needed device replacement due to battery depletion were included in the final analysis

Results
A total of 913 CRT devices were implanted of which 115 (12.59%) were implanted without a left ventricular lead. The left ventricular lead was not implanted due to technical reasons in 46 cases (5%) and electively in the remaining. CRT device replacement (due to Elective Replacement Indicator (ERI) activation) was necessary in 38 patients of the latter and a LV lead had been never implanted in 32 (84.21%) of them during follow-up (7 +/- 2 years). In patients who needed a LV lead added, device replacement (because of battery depletion) was necessary during left ventricular lead implant procedure in 2 (6.25%). Using the average cost of these devices in our institution (22,000 euros), around 384,000 euros could have been saved if the CRT-D had not been implanted until left ventricular lead was.

Conclusions
Implantation of a CRT-D without the left ventricle lead instead of a conventional single/dual chamber ICD in patient with border line indication for CRT is not cost effective and does not result is significant savings in ICD generators.
Association between atrial fibrillation and cardiac implantable defibrillator detected heart failure status
Authors: Vitali F , Tavoletta V , Giano A , Calo L , Santini L , Savarese G , Dello Russo A , Santobuono VE , Mattera A , Lavalle C , Amellone C , Pecora D , Bertini M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
In heart failure (HF) patients, atrial fibrillation (AF) is a common comorbidity and is associated with a worse prognosis. Implantable defibrillator (ICD) diagnostics allow continuous monitoring of atrial high-rate events (AHRE), as a surrogate of AF, and are equipped with algorithms for HF monitoring. We evaluated the association between the values of the multisensor HF HeartLogic Index and the incidence of AF, and assessed the performance of the Index in detecting follow-up periods of significantly increased AF risk.

Methods
The HeartLogic feature was activated in 568 ICD patients. The median follow-up was 25 months [25th–75th percentile: 15-35]. The HeartLogic algorithm calculates a daily HF index and identifies periods IN the alert state on the basis of a configurable threshold. The endpoints were: daily AF burden of ≥5 minutes, ≥6 hours and ≥23 hours.

Results
The HeartLogic index crossed the threshold value 1200 times (0.71 alerts/patient-year). The time IN the alert state was 13% of the total observation period. During the observation period, an AF burden of ≥5 minutes/day was documented in 183 (32%) patients, ≥6 hours/day in 118 (21%) patients, and ≥23 hours/day in 89 (16%). On using a time-dependent Cox model, the weekly time IN the alert state was independently associated with an AF burden of ≥5 minutes/day (HR:1.95, 95%CI:1.22-3.13, p=0.005), ≥6 hours/day (HR:2.66, 95%CI:1.60-4.44, p&lt;0.001), and ≥23 hours/day (HR:3.32, 95%CI:1.83-6.02, p&lt;0.001), after correction for baseline confounders. Comparison of the episode rates in the IN-alert state with those in the OUT-of-alert state yielded HRs ranging from 1.57 to 3.11 for AF burden from ≥5 minutes to ≥23 hours.

Conclusions
The HeartLogic alert state was independently associated with AF occurrence. The intervals of time defined by the algorithm as periods of increased risk of HF allow risk stratification of AF according to various thresholds of daily burden.
External cardioversion of atrial fibrillation and flutter in patients with cardiac implantable electrical devices
Authors: Elgaard AF , Dinesen PT , Riahi S , Hansen J , Lundbye-Christensen S , Thoegersen AM , Larsen JM 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Atrial tachyarrhythmias are often treated with external cardioversion (ECV) with direct current shocks in patients with potentially electrically sensitive cardiovascular implantable electronic devices (CIED). Long-term follow-up data on contemporary pacemakers and implantable cardioverter defibrillators (ICD) undergoing ECV is sparsely described. This study investigated shock-related complications and impact on CIEDs.

Methods
All ECV procedures of atrial fibrillation and flutter from 2010 to 2020 in patients with CIED performed at a tertiary hospital (Denmark) were identified in the Danish National Patient Registry. Data on device interrogation before and after ECV and procedure-related complications were retrieved retrospectively by review of medical records.

Results
We analysed 664 ECV-events performed in 362 CIEDs, median implant time 1.5 year. Mean age of patients at first ECV-event were 69.4±9.7 years and 72.2% were men. We identified two cases of major programming changes and two cases of premature battery depletion (≤3 years after generator implant) following ECV. Minor shock-related device changes were found for impedances, atrial sensing values and pacing thresholds of right ventricle lead. In two cases increased pacing threshold of right ventricle leads following ECV triggered exit-blocks after few months. No patients died due to shock-related device dysfunctions.

Conclusion
Following external cardioversion with transthoracic direct current shocks, sporadic (&lt;1%) but potentially critical changes in device function were identified in patients with contemporary pacemakers and implantable cardioverter-defibrillators. The present study suggests that routine post-cardioversion device interrogation is imperative for patient safety.