bluuebunny/crossref_metadata_2025_split huggingface dataset:
Barriers against left bundle branch area pacing, myocardial or electrical disease: what is the matter?
Authors: Briongos Figuero S , Estevez Paniagua A , Sanchez Hernandez A , Munoz-Aguilera RT 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Conduction system pacing via left bundle branch area pacing (LBBAP) can provide physiologic pacing by capturing the LBB (LBBP) or the deep left ventricular septal (LVS) myocardium. Several criteria can distinguish between both types of LBBAP.

Methods
Prospective study of consecutive patients who received LBBAP device for bradycardia or heart failure indications (bailed-out strategy).
LBBP was defined if monopolar paced QRS had a right bundle branch conduction delay pattern, at least one of the following criteria:
(a) Demonstration of LB potential with LB-local ventricular electrogram interval of 20–35 ms.
(b) Demonstration of transition in QRS morphology from NSLBBP to SLBB P capture or NSLBBP to LVS capture (sudden decrease in LVAT of 10 ms) with decrementing output.
(c) Peak LV activation time as measured in leads V5–V6 &lt;80 ms.
We tried to determine the influence that QRS width and LVEF have on the final paced morphology (LBBP or LVS) achieved, during LBBAP.

Results
A total of 149 patients (77 males) were included at our institution. LBBAP was achieved in 145 patients (97.3%). Mean age was 79.2±9.2 years, QRS width was 119.3±19.5 ms, a narrow (&lt; 120 ms) QRS complex was present in 77 patients (51,7%) and LVEF ≤ 40% in 16 (10,7%). Indications for pacing were complete AV block (n=30), degree AV block (n=25), slow AF (n=21), bifascicular or trifascicular block (n=11), sinus node disease or bradi-tachy syndrome (n=55) and need for resynchronization therapy (n=6). A Medtronic 3830-69 lead was implanted using a C-315-His sheath in all procedures. His mapping was not perfomed to select the target delivery zone.
Overall, paced QRS duration after LBBAP was 115.6±14.8 ms. LBBP was achieved in 112 patients (NSLBBP in 63 and SLBBP in 49) while LVS was achieved in the remaining 30 patients. Left bundle potential was seen in 62 patients (41.6%) and mean LVAT (measured at V5/V6) was 80.1±11.3 ms.
As seen in table 1, LBBP was less often achieved among wide QRS patients compared to narrow QRS patients. Moreover, left bundle potential appeared less frequently and, paced QRS duration and LVAT were more prolonged, despite the significant reduction in QRS duration observed among wide QRS complex patients.
Paced QRS duration after LBBAP was longer among patients with LVEF≤40% compared to patients with LVEF&gt;40%, and LBBP was also more difficult to achieve (table 2).
We specifically analyzed the subgroup of patients with wide QRS complex (n=72). LBBP among those with LVEF≤40% (n=12) was only achieved in 54.5% compared to patients with LVEF&gt;40% (71.4%). Paced QRS duration (130.9±13.6 vs 119±15.1; p=0.002) and LVAT were also longer (92.3± 8.7 ± 81.3±11.1; p=0.020).

Conclusions
Electrical delay and myocardial disease represent two barriers to achieve LBBP. The combination of both conditions might select a subgroup of patients in which LBBAP supposes a challenge.
Short term outcomes of distal (ventricular) His bundle pacing: A single centre retrospective study
Authors: Vali Z , Ebeid A , Man S , Abuelmagd K , Dhutia H , Somani R , Ng GA , Ibrahim M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Chronic right ventricular apical pacing can lead to pacing induced cardiomyopathy in a significant proportion of patients. Conduction system pacing may restore more physiological activation of the heart, and has recently been shown to have favourable outcomes in clinical trials. However there remains concern regarding the long-term outcomes due to lead displacement and high pacing thresholds. The most widely used technique in current practice is to pace the His bundle proximal to the tricuspid valve. Distal His bundle pacing has a number of advantages over proximal His pacing, including, lower capture thresholds, a more stable lead position, less far field atrial sensing and better spacing from the AV node in case ablation of this is required for AF rate control. Despite these, outcomes of distal His bundle pacing from the ventricular aspect are less well defined.

Methods
We performed a retrospective review of patients who underwent conduction system pacing between January 2020 and October 2021 at our centre. During this period all procedures were performed employing a distal His bundle pacing approach with the lead placed on the ventricular aspect of the tricuspid annulus. Data was collected at implant, follow-up at 1 month and then every 6 months.

Results
Out of 35 patients, 33 underwent successful His bundle pacing (acute success rate of 94%), 1 patient had left bundle branch pacing and another patient had an unsuccessful procedure. Mean age was 74 years, median LVEF 45% and median pre-implant QRS was 108ms. 80% of the cohort had a history of AF. The indications for pacing were as follows: AF - for pace & ablate (60%); high grade AV block with narrow QRS and mild LVSD (17%); failed LV lead (14%); and other 9%. Mean procedure duration and fluoroscopy time were 78 minutes and 12.05 minutes, respectively. Median threshold at implant was 1.00V (IQR 0.719V). Selective His bundle pacing was achieved in 60% and non-selective in 34%. Mean follow-up duration was 150 days with median threshold at last f/up of 0.75V (IQR 0.750V). There were no acute procedural complications. 1 patient had a significant rise in threshold at follow-up and therefore required upgrade to CRT-P.

Discussion
Our data shows that distal His bundle pacing is a safe and effective technique for conduction system pacing. Thresholds appear stable at follow-up and failure rate was found to be comparable to biventricular pacing. We noted an initial learning curve for both implanter and physiologists with relatively poorer outcomes for the earlier cases. Longer term follow-up is ongoing, including functional assessment and follow-up to assess for remodelling with echocardiography. Prospective randomised trials are needed to compare conduction system pacing vs RV pacing in AF patients with HFpEF or mild LVSD undergoing AVN ablation, and vs biventricular pacing in the severe LVSD population.
Changes in the implantation procedures of pacemakers during the COVID-19 pandemic in Germany
Authors: Schwab JO , Wiese J , Hauser T 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): BIOTRONIC

Background
During the beginning of the first pandemic wave beginning in spring 2020 a lot of elective EP procedures were set on hold. After a few months, the hospitals were allowed to proceed with their planned operations. The current investigation analyzed the changes in the number of cardiac pacemakers (PM) implantations in whole Germany.

Methods
We performed a data retrieval of the number of monthly first-time pacemaker implantations, i.e. single-, dual-chamber, or CRT-P, for the 2019 pre- and 2020 pandemic from the "Institut für das Entgeltsystem im Krankenhaus" (InEK) using OPS codes. This database provides data of all in-hospital procedures in Germany.

Results
The course of the implantation rates (January to September) is highlighted in the two figures, where figure 1 demonstrates the single- and dual-chamber PM, and figure 2 the CRT-P implantations in 2019 (blue line) compared to 2020 (red line). It can be clearly seen, that for the single- and dual-chamber PM, a gap occurs between March and Mai in 2020. On the contrary, for the sicker patients, who are in the need for CRT-P, the lines do no cross, significantly. Moreover, the number of CRT-P first-time implantations increased during May to September 2020.

Discussion
The present study highlights the course of first-time pacemaker implantations throughout the beginning of the COVID-19 pandemic in whole Germany. In contrast to single- and dual-chamber PM implantation rates, the number of CRT-P implantations remained stable during the first three months of the pandemic and then exceeded the rates from 2019. The progressive nature of heart failure resulting in the need for CRT may be one reason for not postponing the first-time implantation in the months March to May 2020.
Left Bundle Branch Pacing: procedural outcomes using different sheaths
Authors: Marcantoni L , Centioni M , Pastore G , Manzato E , Fornasaro M , Cappato E , Pigaiani C , Marsiglia S , Baracca E , Zanon F 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left Bundle Branch Pacing (LBBP) ensures physiologic ventricular activation. Growing experiences are rising on its applicability . Different tools available allow successful implant in different cardiac anatomies.

Objective
To analyse implant success rate and acute electrical parameters in LBBP guided by C315 fixed curve sheath or Selectra3D sheath.

Methods
151 patients (mean age 79.8±8.3 years; 51% males) received LBBP. Pacing indication: AV block 50%, SND 12%, slow AF12%, ablate&pace 9%; HF 14%, revision of previous lead 1%. Coronary disease was present in 31%; hypertension in 93%, diabetes in 30%, severe valvular disease in 5%, persistent AF in 31% pts. Average QRS duration was 136±34 ms. Basal mean EF 52±12%. Different criteria for successful LBBP were analyzed (table 1).

Results
The lead was successfully implanted in the left bundle in 97.3% pts. In 60.5% pts guided by the C315 Medtronic fixed curve sheath while in 39.5% pts by the Selectra3D (40-S, 55-M, 65-L) Biotronik sheaths. 93 (63%) pts received 3830 fixed screw lead, 51 (35%) pts received Solia S 60 stylet-driven lead and 3 (2%) patients received Tendril 58 cm stylet-driven lead. All different criteria analysed to define successful LBBP were comparable in the C315 and Selectra 3D group (table 1). In 61% pts LBBP was the first choice, in 39% LBBP was aimed after unsatisfactory HBP (His threshold&gt;2V or paced QRS&gt;140 ms). The LBBP lead was connected to the RV port in 67% DR and 18% SR PMs; to the LV port in the 22 CRT devices. Mean fluoroscopy time was 10±6 min including implant of all leads, without differences between implants. Electrical parameters were highly favourable in all patients (mean threshold 0.73±0.27V and mean sensing 11±5.8 mV) without differences between the 2 sheaths. Pacing impedance was significantly lower in the Selectra 3D group. Paced QRS duration was 114±15 ms (112±14 vs 116±16 ms; P 0.180). Implant failure were 4 (2 due to severe tricuspid regurgitation and 2 to severe dilated atria).

Conclusion
LBBP is highly reliable in clinical practice. The different sheath available lead to successfully perform the implant in different cardiac anatomies. In our experience there was no differences in technical acute outcome between implant guided by C315 Medtronic sheath and Selectra3D Biotronik sheath.
Conduction system pacing with Selectra 3D Sheath: Technical Results
Authors: Marcantoni L , Centioni M , Pastore G , Baracca E , Marsiglia S , Fornasaro M , Pigaiani C , Cappato E , Manzato E , Zanon F 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Conduction system pacing (CSP) allows physiological electrical activation. The Selectra3D sheath is a new tool able to guide the lead implantation on the His Bundle (HBP) or on the left bundle branch (LBBP). It does exist in 3 different shapes (40-S, 55-M, 65-L).

Objective
To evaluate the effectiveness of different Selectra3D introducers for CSP, considering the procedural success, stability of electrical parameters or need for implant revision at medium-term follow-up.

Methods and results
Selectra3D was used in 113 CSP procedures between Nov 2019 and Nov 2021. Mean patients age was 80±6 years, 54% males. Pacing indications were: AV block 52.2%, slow AF 12.4%; SND 12.4%, ablate&pace 5.3%, implant revision 0.9%, cardiomyopathy 16.8%. Mean EF was 40±15%. Single chamber PM was implanted in 4.8% pts, dual chamber PM in 57.1% pts while 26.2% and 11.9% pts received CRT-P and CRT-D devices respectively. Stylet-driven lead was used in 75 pts, fixed screw lead in 38 pts. HBP was obtained in 34% pts, LBBP in 55% pts, HBP+LBBP in 3% pts, while 8% cases were CSP implant failure (7 lead implanted in the septum; 2 in the coronary sinus). Selectra3D was the first delivery used during the procedure in 88% of cases (55-M in 76%; 40-S in 9%; 65-L in 3%), while was the second tool (after failure of the first delivery utilised) in the other pts. The first Selectra3D utilized during each implant was able to complete the procedure in 64% of cases, while in the other pts a second different tool was required to complete the implant. The Selectra3D 55-M was the mostly used and was able to reach the final position in most cases. In dilated atria the 65-L curve was preferred, while when the target point was more proximal the 45-S curve was the best choice. The baseline QRS duration was 135 ± 34 ms and the paced QRS duration was 113 ± 18 ms (P 0.003). The electrical parameters were optimal with sensing 8.7 ± 8 mV; impedance 562 ± 133 ohm; threshold 0.97 ± 0.47 V. During a median follow-up of 178 [34-402] days, 7 lead dislodgement (3 HBP and 4 LBBP) were recorded. All the others showed stability of the electrical parameters.

Conclusion
The Selectra3D introducers effectively supports CSP ensuring procedural success rate&gt;90%. The 55-M curve fits for most of the anatomies, the 45-S curve allows to reach more proximal target, the 65-L curve more distal target in dilated atria. The electrical parameters were optimal at implant and remained stable during follow-up. 6% lead dislodgement were recorded.
The use of artificial intelligence and deep learning methods in subcutaneous implantable cardioverter defibrillator screening to optimise selection in special patient populations
Authors: Elrefai M , Abouelasaad M , Conibear I , Wiles B , Dunn A , Coniglio S , Zemkoho A , Roberts P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Dr.Mohamed ElRefai is receiving an unrestricted grant from Boston Scientific.

Introduction
Adult congenital heart disease (ACHD) and hypertrophic cardiomyopathy (HCM) patients who require defibrillator therapy are often relatively young and may require several generator replacements in their lifetime. The increased risk of complications associated with transvenous ICDs make the subcutaneous (S-ICD) a valuable alternative. However, higher S-ICD ineligibility rates (20-40% in ACHD and 7-38% in HCM) and higher inappropriate shock rates (10.5% in ACHD and 12.5% in HCM) are observed in these populations. Unfavourable T:R ratios and dynamic changes in the R and T wave amplitudes are the primarily factors behind ineligibility and inappropriate shocks, which are most commonly caused by T wave over-sensing.

Purpose
We report a novel application of deep learning methods used to autonomously screen patients for S-ICD eligibility over a longer period than conventional screening. We hypothesise that this screening approach might achieve better patient selection and optimise S-ICD vector selection in challenging patient cohorts.

Methods
Adult patients with ACHD or HCM and a control group of normal subjects were fitted with a 24-hour ambulatory ECG with the leads placed to record their S-ICD vectors. T: R ratio throughout the recordings was analysed utilising phase space reconstruction matrices to convert the ECG signal into compressed pixel images. Whilst a convolutional neural network model was trained to provide an in-depth description of the T: R variation plot for each vector T: R variation was compared statistically using a one-way ANOVA test.

Results
20 patients (age 44.1 ±11.68, 60% male, 7 HCM, 6 ACHD and 7 control subjects) were enrolled. A significant difference was observed in the mean and median T: R values between the three groups (p&lt;0.001). There was no difference observed in the standard deviation of T: R between the control subjects and HCM group. However, there was a statistically significant difference in the standard deviation of T: R between the control subjects and the ACHD group (p= 0.01). [see Figure].

Conclusions
T:R ratio, a main determinant for S-ICD eligibility, is significantly higher in ACHD and HCM when compared to normal hearts and it also has more tendency to fluctuate in ACHD patients when compared to HCM and normal hearts populations. We hypothesise that our novel model could be used to select S-ICD eligible patients by better characterisation of T:R ratio reducing the risk of T wave oversensing and inappropriate shocks particularly in the ACHD patients’ cohort.
Impact of coronary anatomy and residual syntax score on arrhythmic events in patients with ischemic cardiomyopathy
Authors: Meynet I , Quadri G , Tricomi L , Tomassini F , Rolfo C , Franze’ A , Zanda G , Piedimonte G , Minniti D , Varbella F 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
ICD implantation is a cornerstone for primary prevention in patients with ischemic cardiomyopathy and impaired left ventricular function; reduced ejection fraction alone, however, doesn’t seem enough to discriminate which patients will really experience arrhythmic events in the follow up.

Purpose
We hypothesized that coronary anatomy and the extent of residual coronary lesions, measured with syntax score, could be a better predictor of the outcome in this setting.

Materials and method
Data of all patients implanted with single or dual chamber ICD in primary prevention for ischemic cardiomyopathy from 2011 to 2020 were retrospectively collected, together with follow up data obtained from clinical visits and ICD remote monitoring. Residual syntax score (RSS) was calculated for each patient, taking into consideration the last coronary angiography performed before ICD implantation.

Results
110 patients were included in our registry. 90.1% were male, mean age was 66±7 years. 23.6% ICD were dual chamber devices. 96 (87.2%), 8 (7.3%) and 6 (5.5%) patients presented respectively with low (0-22), intermediate (23-32) or high (≥33) RSS. After a mean follow up of 4.4±2.9 years, 31 patients (28.2%) died; 20 patients (18.2%) and 27 patients (24.5%) received any appropriate ICD therapy, either shock or ATP. 12 patients (10.9%) experienced inappropriate shock. The composite outcome of death or any appropriate therapy (MACE) was observed in 47 patients (42.7%); left main or left descending artery stenosis were predictors of MACE (p = 0.026 and p = 0.040, respectively). Intermediate or high RSS was the only predictor of appropriate shock (p = 0.046).

Conclusions
Coronary anatomy and residual coronary stenosis quantified with syntax score are promising predictors of arrhytmic events during the follow up in patients with ischaemic cardiomyopathy and ICD implanted in primary prevention.
Intraoperative defibrillation testing during replacements of implantable cardioverter-defibrillators: The Simpler trial
Authors: Milman A , Nof E , Beinart R , Regev E , Rav Acha M , Kutyifa V , Merkely B , Biffi M , Cha YM , Ovdat T , Klempfner R , Glikson M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Maurice Kahn Foundation via the Mayo- Sheba Collaboration Fund.

Background
The need for intraoperative defibrillation testing (DFT) during implant and/or replacement of implantable cardioverter-defibrillators (ICDs) has been a matter of debate for many years. This debate was put to rest by the Simple and the Nordic ICD trials, and the practice of testing during new implantations has practically been nearly abandoned.
Nevertheless, induction of VF for testing purposes (VFT) may still have an important role in selective populations at risk for defibrillation failure, who were not included in the SIMPLE and Nordic trials. One such population includes those who undergo device replacements. Old registries demonstrated an increased incidence of significant findings in VFT during replacements. In the present study, we sought to test this observation.

Objectives
Evaluate frequency of significant findings and the safety of VFT in subjects undergoing device replacement.

Methods
A prospective observational multi-center study of VFT included consecutive patients undergoing ICD generator replacement in 5 centers in Israel, Europe, and the US. All centers followed the same VFT protocol. The primary outcome was defined as failure to terminate induced VF with a single shock at 10 Joules below the maximal capacity of the device. Secondary outcomes included complications of VFT. Patients were followed-up at 1 month and 6 months post-procedure. Data collection included documentation of any peri-operative complications and clinical endpoints (occurrence of appropriate shock, inappropriate shocks, lead failure, need for re-intervention, and infection).

Results
A total of 92 patients were eligible, and consented for the study, of which 84 underwent DFT during battery replacement. The median age was 68 years and 79.8% were male subjects. Induction of VF was successful in all 84 patients as well as VFT with a successful conversion on first attempt. During follow up one patient had two appropriate ICD shock events. In four patients, the ICD programming was changed. None suffered an inappropriate shock. There was no evidence of lead malfunction. A total of two deaths occurred, none of which were related to the device.

Conclusion
The present study found VFT was not associated with complications in patients undergoing ICD/CRTD generator replacement but produced no clinically important information.