bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated external defibrillator delivery by a drone in a mountainous region to treat sudden cardiac arrest
Authors: Fischer P , Rohrer U , Nuernberger P , Manninger M , Scherr D , Von Lewinski D , Zirlik A , Wankmueller C , Kolesnik E
Published: May 2023

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): ZOLL

Introduction

Out-of-hospital cardiac arrest (OHCA) poses a tough medical challenge with poor survival rates. Factors that may enable survival include resuscitation measures initiated by a bystander, early use of an automated external defibrillator (AED), and further performance of advanced life support. The latter will arrive on scene with an inevitable time-delay due to logistics challenges and potential AED unavailability, especially in rural areas. Here, drones might deliver an AED in order to increase the probability of survival.

Methods

Ten paramedics and nineteen medical laypersons were confronted with a person suffering from OHCA within a field test scenario in a mountainous region (Bodental, Carinthia, Austria) without detailed information. The scenario included a mock-call to the emergency response center responsible for the Austrian State Carinthia that dispatched a semi-autonomously flying drone towards the caller’s GPS coordinates. During the emergency call, participants should perform cardiopulmonary resuscitation (CPR) measures and were informed that a drone delivers a training-AED. Various timepoints (time to (tt) emergency call, tt start CPR, tt drone start, tt first shock, hands-off times) as well as CPR quality were subject of analysis.

Results

The paramedics realized the cardiac arrest after 21 ± 11 seconds, the emergency call was performed after 40 ±43 seconds, the drone started after 5:15 ± 2:11 minutes and dropped off the AED after 10:52 ± 2:06 minutes, and the first shock was delivered after 12:15 ± 2:03 minutes. 70 % performed adequate chest compressions and 50 % provided sufficient mouth-to-mouth ventilation. Hands-off times were 50 ± 22 seconds. Only 37 % of the medical laypersons reported to know the algorithms for basic life support while 32 % performed adequate chest compressions and 68 % performed adequate mouth-to-mouth ventilation. In this group, the cardiac arrest was realized after 51 ±40 seconds, the emergency call was performed after 53 ±43 seconds, the drone started after 6:15 ± 1:33 minutes and dropped off the AED after 10:54 ± 1:56 minutes, and the first shock was delivered after 14:04 ± 2:10 minutes. Hands-off times were 2:11 ± 0:39 minutes.

Conclusion

The delivery and usage of an AED via a semi-autonomously flying drone in a remote region is feasible and safe. The drone delivery of an AED in mountainous regions can lead to early application of shocks. CPR quality performed by medical laypersons is suboptimal and emphasises the need for regular trainings.
Zero and near zero fluoroscopy catheter ablation of premature ventricular contractions: a multicentre experience
Authors: Mugnai G , Velagic V , Malagu M , De Asmundis C , Tomasi L , Bolzan B , Chierchia G B , Ribichini F L , Stroker E , Bertini M
Published: May 2023

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation has become an established treatment option for premature ventricular complexes (PVCs). It is well known that the use of fluoroscopy exposes patients and medical staff to potentially harmful stochastic and deterministic effects of ionising radiations.

Purpose

We sought to analyse procedural outcomes in terms of safety and efficacy using a "zero" or "near zero" X rays approach for treatment of PVCs.

Methods

The present retrospective, multicentre, observational study included 131 patients having undergone catheter ablation of PVCs using zero or "near zero" (less than 2 minutes) fluoroscopy between 2016 and 2020. Baseline characteristics of the population, acute success and complications derived from the procedure were evaluated, as well as recurrence rate during follow-up.

Results

Median age was 51.0 years old [38-63], males were 77 (58.8%). Most often cause of ablation were palpitations (90.0%), followed by reduced left ventricular ejection fraction (4.6%) and pre-syncope (14.5%). Among the study population, 26 (19.8%) had a cardiopathy. The median PVC burden before ablation was 15.1% [6%-22.4%]. The most frequent PVC origin was right ventricular outflow tract (n=72; 55.0%) followed by the left ventricle (n=21; 16.0%), LVOT and cusps (n=18; 13.7%) ,aortomitral continuity (n=7; 5.3%).

A 3D electro-anatomical mapping system was used in all cases as well as a contact force catheter for mapping and ablation. The mean maximum radiofrequency power applied was 32.9 ± 4.1 W (370 s median time). Median number of applications was 4.5 and mean total procedural time was 117.3 ± 47.5 minutes. Median best prematurity was 31.5 ms. We used isoprenaline in order to induce PVCs in 42% of cases and suppression of PVC was achieved in 127 patients (96.9%). There was only 2 complication (femoral hematoma and arteriovenous fistula conservatively treated). At 12 months, a complete success was documented in 109 patients (83.2%), a reduction in PVC burden was achieved in other 18 patients (13.7%) and a failure was recorded in 4 patients (3.1%).

Conclusion

The PVC ablation with "zero" or "near-zero" fluoroscopy is a safe procedure with no major complications and good rates of success and recurrence in our multicentre experience.
Reproducible target transfer from electroanatomic mapping to radiotherapy planning systems for cardiac radioablation - cross-validation for the RAVENTA trial
Authors: Hohmann S , Xie J , Grehn M , Karfoul N , Mehrhof F , Merten R , Rudic B , Krug D , Lyan E , Duncker D , Dunst J , Tilz R , Schweikard A , Blanck O , Boda-Heggemann J
Published: May 2023

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): RAVENTA is part of the EU-Horizon-2020 STOPSTORM project.

Background

Ventricular arrhythmias are a leading cause of morbidity and mortality in patients with structural heart disease. Non-invasive stereotactic single-fraction arrhythmia radioablation (STAR) with 25 Gy has been proposed as a bail-out strategy in patients where catheter-based ablation is either not feasible or has previously failed to control the arrhythmia. Defining the exact radiotherapy target, however, presents unique challenges, and manual transfer of locations from the electroanatomic map (EAM) into the cardiac CT results in a high degree of uncertainty.

Different workflows have been developed to register EAM with the cardiac CT and allow for target definition in EAM space with semi-automated transfer of the target structure to CT coordinates. Validation of these approaches is presently lacking. Here we report the initial cross-validation results of two conceptually different software solutions for target transfer quality assurance in STAR.

Methods

Clinical case data of patients treated with STAR (EAM data, cardiac CT and screenshots of the map with marked target region) were collected retrospectively from centres participating in the RAdiosurgery for VENtricular TAchycardia (RAVENTA) trial. Two blinded investigators independently created a target volume in the cardiac CT based on the marked target region using either a 3D-3D registration approach (3D Slicer / EAMapReader) or a 2D-3D registration (CARDIO-RT), as described previously. The resulting target structures were analysed in a core lab for overlap and similarity by means of surface distance metrics and conformity.

Results

Three clinical data sets were analysed, one for each mapping system in widespread clinical use. Agreement between structures created with both approaches was good, with DICE coefficients of 0.88, 0.69 and 0.506 and median surface distances of 0 mm, 1.2 mm and 2.2 mm, respectively. The least agreement was seen in a case where no additional structures were mapped besides the LV, whereas additional anchor points such as the ascending aorta seem to reduce registration ambiguity.

Conclusion

Using two conceptually different approaches for the target transfer from EAM to cardiac CT we were able to show good agreement between both methods. Both techniques thus can be used for quality assurance and analysis in STAR. Further study in a larger sample of patient data sets is warranted to elucidate differences between transfer methods and predictors for improved registration.
Prognosis of patients undergoing catheter ablation of arrhythmic storm in patients with and without history of previous ICD interventions
Authors: Telesca A , Bencardino G , Scacciavillani R , Perna F , Narducci M L , Comerci G , Pinnacchio G , Spera F R , Gabrielli F A , Pelargonio G , Massetti M , Crea F
Published: May 2023

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation (CA) improves prognosis in patients with electrical storm (ES). However, its effectiveness and timing in patients with ventricular tachycardia and appropriate ICD therapies remain a matter of debate.

Purpose

Our aim was to investigate whether patients with history of discrete ventricular tachycardia episodes had different clinical features and outcome compared to patients with ES as first arrhythmic occurrence.

Methods

We enrolled 57 consecutive patients undergoing CA for ES and collected clinical, echocardiographic and electroanatomic mapping data. The primary end point was a composite of death from any cause and recurrences of sustained VT or ventricular fibrillation, appropriate ICD therapy, or ES.

Results

During a median follow up of 39 months, 28 patients (49%) met the primary end point of arrhythmic recurrence or death from any cause. There were no significant differences between clinical, electrocardiographic and echocardiographic parameters in the two groups.

Regarding ICD therapies, patients with who met the primary end point had a higher number of ATP/shock episodes preceding the ES event: 15 (52%) vs 25 (89%), p=0.002. At Cox regression analysis, NIDCM, previous ATP and/or shock and ≥3 ATP were associated with arrhythmic recurrences and/or death.

At multivariate analysis, ≥3 ATP was the only predictor that met statistical significance for the primary end point: HR was 30.41, CI 4.42 – 209.12, p=0.001.

When dividing our population in patients and without ventricular arrhythmias (VAs) with appropriate device intervention before ES, thoses with VAs arrhythmias before ES had a higher percentage of presence of late potentials (80% vs 55%, p=0.041) and a greater unipolar scar (59.2±41.6 vs 30.2±21.6, p=0.001). At univariate analysis the presence of late potentials was associated with ventricular arrhythmias before ES (OR 3.33, CI 1.03-10.84, p=0.045).

Conclusions

CA in patients with a long arrhythmia history, recurrent ICD therapies and presence of late potentials at electroanatomic mapping, may yield worse outcomes and therefore our results support an early referral for CA of VT to improve prognosis in these subjects.
Effect of ventricular tachycardia ablation on symptoms and health-related quality of life: data from a single-center registry
Authors: Charitakis E , Valera Soria C , Almroth H , Karlsson L , Guidi C , Sandgren E , Liuba I , Balata D , Hassel Jonsson A , Walfridsson H , Walfridsson U
Published: May 2023

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ALF grants (County Council of Östergotland).

Background

Ventricular tachycardia (VT) is a significant cause of morbidity and mortality (1). Implantable cardioverter-defibrillators can terminate the arrhythmia and reduce the risk of sudden cardiac death but do not lower the risk of recurrence (2). Thus, the use of VT ablation as a method of prevention of VT recurrence has increased (3). Most articles have focused on the procedure’s efficacy and complications as opposed to data concerning arrhythmia-related symptoms and health-related quality of life (HRQoL).

Purpose

We sought to examine the effect of VT ablation on patients’ symptoms and HRQoL during a one-year follow-up period.

Method

Patients referred for catheter ablation of VT to our university hospital between June 2012 and June 2020 were asked to fill in the validated ASTA (Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia) questionnaire for the assessment of symptoms and HRQoL before and one year after the index procedure.

Results

One hundred sixty-one patients filled out the ASTA questionnaire before the index procedure and 133 (83 %) at one-year follow-up. Four patients died during follow-up. Of the 133 patients eligible for analysis, 53 had ischemic VT, 45 had non-ischemic VT, and 35 had idiopathic VT. Sixty patients were also followed up in detail concerning arrhythmia recurrence by screening ICD interrogation reports, ECGs, and Holter registrations. Repeated measures analysis of variance showed a significant reduction of symptoms and improvement of HRQoL irrespective of patients’ background disease (ASTA-symptom score: whole population, as well as subpopulations p<0.001, figure 1, ASTA-HRQoL score: whole population as well as subpopulations p<0.001, figure 2) after 1.6 procedures, while 41 % of patients did not report any arrhythmia-related symptoms after one year. Sixty-eight percent of the patients did not suffer any recurrence during the first year after catheter ablation, and the major complication rate was 7%.

Conclusions

Catheter ablation of VT effectively reduces arrhythmia-related symptoms and improves HRQoL irrespective of patients' background disease during a follow-up period of one year.
Accuracy of a novel ECGi system in localising the critical isthmus exit site in scar-dependant re-entrant ventricular tachycardia
Authors: Al-Sheikhli J , Patchett I , Marshall L , Khan J , Dhanjal T
Published: May 2023

Funding Acknowledgements

Type of funding sources: None.

Introduction

Vision in ventricular onset (VIVO) is a novel, non-invasive, mapping system designed to locate the site of earliest activation in ventricular arrhythmia. VIVO utilises a mathematical algorithm, cross-sectional imaging data (CT or MRI), 3D images of the electrodes on the patient torso, and a 12-lead electrocardiogram (ECG) to identify the site of earliest ventricular activation.(1) The system has been shown to accurately predict earliest activation of focal premature ventricular contractions (PVCs), but its accuracy in scar dependant re-entrant ventricular tachycardia (VT) has not been investigated.(1-3)

Objective

To assess the accuracy of VIVO in localising the VT exit site for patients with ischaemic cardiomyopathy (ICM) and scar related re-entrant VT.

Methods

5 patients with ICM (age 56 ± 19 yrs, male n = 5) were investigated (table 1). All patients had an implantable cardioverter-defibrillator with standard indications for VT ablation. Invasive electro-anatomical mapping was performed with the Advisor HD Grid multipolar catheter and maps were generated using omnipolar electrograms (EGMs). The VT exit site was identified using activation ± pace-maps and the location defined by the primary operator using the American Heart Association (AHA) 17 segment model of the left ventricle.(4) Using the intra-procedural VT ECG recordings, VIVO maps were constructed post-procedure. The VIVO predicted VT exit site was identified using the AHA 17-segment model by a second operator, blinded to the results of the procedure. A "complete match" was defined as exact segment concordance between the two operators, "partial match" as adjacent segments, and "no match" if neither requirements satisfied.

Results

Mean left ventricular ejection fraction was 30.5 ± 9.0%. Mean procedure time was 233 ± 31 minutes, with a mean ablation time of 24 ± 18 minutes. A total of 11 re-entrant VTs were mapped. The VT exit site was identified in all cases (10 activation-map; 1 pace-map). A complete match was seen in 91% of VTs and partial match in 9% (table 2). None of the cases demonstrated a "no match" between the invasive and VIVO maps. There were no procedural complications.

Conclusion

The VIVO mapping system can accurately predict the VT exit site in scar dependant re-entrant VT. Further studies to assess the feasibility of VIVO-guided ablation in scar dependant VT are ongoing.
The importance of the right ventricular insertion area for the functional substrate of ventricular tachycardia after myocardial infarction
Authors: Takamiya T , Rademaker R , Riva Silva M , Kimura Y , Zeppenfeld K
Published: May 2023

Funding Acknowledgements

Type of funding sources: None.

Background

Conducting systematic annotation and ablation of evoked delayed potentials (EDP) in response to short coupled right ventricular extra-stimuli (RV-ES) has improved ablation outcome of post myocardial infarction (MI) ventricular tachycardia (VT). The reported short radiofrequency catheter ablation (RFCA) times suggests the presence of predilection areas for these functional substrates.

Purpose

To evaluate the electroanatomical characteristics and distribution of EDPs in post-MI patients referred for RFCA of VT.

Methods

Electroanatomical mapping (EAM) data of 48 post-MI patients (69 ± 9 years, 39 male, LV ejection fraction 36 ± 10%, anterior MI 20 [42%], inferior MI 28 [58%]), who underwent functional substrate mapping and ablation were analyzed. Pre-procedural cardiac CTs of 16 patients (8 anterior, 8 inferior MI) were integrated with EAM data. Infarct extension (defined as bipolar voltage [BV] <3.0mV, dense scar <0.5mV and scar borderzone [BZ] 0.5-3mV) and EDP location were determined based on the AHA 17-segment model of the left ventricle.

Results

RV-ES was performed during mapping at 2180 LV sites (median 46 per patient, range 8-81) and EDPs were observed at 631 (29%) sites. Patients had a median of 11 (range 1-37) EDP sites. Compared to no-EDP sites, EDP sites had lower BV (median 0.57 mV vs. 0.77 mV, P <0.001), longer duration (median 79 ms vs. 66 ms, P <0.001), and larger number of positive sharp deflections (median 6 vs. 5, P <0.001) during sinus rhythm. Of all EDP sites, 278 (44%), 286 (45%), 64 (10%), and 3 (1%) had BV of <0.5mV, ≥ 0.5mV and <1.5 mV, a BV of ≥1.5 mV and <3.0 mV, and a BV of >3.0 mV, respectively. In the 16 patients with CT image integration, a total of 124/272 segments showed EA scar with a median (IQR, range) of 8 (6-9, 4-12) segments per patient. Any EDP was identified in 71/124 (57%) of segments with EA scar. Of note, 73% of all EDPs in inferior MIs and 64% of all EDPs in anterior MI were located in 4 AHA segments, namely 3,4, 9,10 and 7,8,13,14, respectively, close to the inferior or anterior RV insertion. Such a cluster of EDP sites around the RV insertion was found in 6 (75%) patients with inferior MI and in 7 (88%) patients with anterior MI.

Conclusion

About 10% of EDPs are identified at sites with BV of ≥1.5mV and <3.0mV during sinus rhythm supporting the recently proposed BV threshold <3.0mV for post-MI scars. EDPs are frequently located near the RV insertion in both inferior MI and anterior MI suggesting a role of the RV insertion in the functional substrate of post-MI VT.
Evolution of deceleration zones during VT ablation and relation with cardiac magnetic resonance
Authors: Vazquez-Calvo S , Garre P , Ferro E , Falzone P , Uribe L , Guichard J B , Ortiz-Perez J T , Guasch E , Arbelo E , Tolosana J M , Mont L , Porta-Sanchez A , Brugada J , Roca-Luque I
Published: May 2023

Funding Acknowledgements

Type of funding sources: None.

Background

A new functional mapping strategy based on targeting deceleration zones (DZs) has become one of the most commonly used strategies within the armamentarium of substrate-based ablation methods for ventricular tachycardia (VT) in patients with structural heart disease. The classic conduction channels detected by voltage mapping can be accurately determined by cardiac magnetic resonance (CMR).

Objectives

To analyze the evolution of DZs during ablation and their correlation with CMR.

Methods

Forty-two consecutive patients with scar-related VT undergoing ablation after CMR (October 2018-December 2020) were included (medium age 65.3±11.8 years; 94.7% male; 73.7% ischemic heart disease). Baseline DZs and their evolution in isochronal late activation remaps were analyzed. A comparison between DZs and CMR conducting channels (CMR-CCs) was realized. Patients were prospectively followed for VT recurrence for one year.

Results

Overall, 95 DZs were analyzed, 93.68% of which were correlated with CMR-CCs: 44.8% located in the middle segment and 55.2% located in the entrance/exit of the channel. Remapping was performed in 91.7% of patients (1remap: 33.3%, 2remaps: 55.6% and 3remaps: 2.8%). Regarding the evolution of DZs, 72.2% disappeared after the first ablation set, with 14.13% not ablated at the end of the procedure. A total of 32.5% of DZs in remaps correlated with a CMR-CCs already detected, and 17.5% were associated with an unmasked CMR-CCs. One-year VT recurrence was 22.9%.

Conclusions

DZs are highly correlated with CMR-CCs. In addition, remapping can lead to the identification of hidden substrate initially not identified by electroanatomic mapping but detected by CMR.
Characteristics of recurrent ventricular tachycardias after stereotactic body radiotherapy
Authors: Peichl P , Wichterle D , Cvek J , Stojadinovic P , Cihak R , Kautzner J
Published: May 2023

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Grant project AZV NU20-02-00244 from the Ministry of Health of the Czech Republic and European Union's Horizon 2020 research and innovation program under grant agreement No 945119.

Introduction

Stereotactic body radiotherapy (SBRT) is a novel treatment for otherwise resistant ventricular tachycardias (VTs). Different mechanisms of SBRT for VT suppression were proposed that include radiation-induced fibrosis but also SBRT-triggered increase in myocardial conduction velocities without significant fibrotic changes.

Purpose

The study compared the morphologies and cycle lengths (CLs) of inducible VTs during re-do catheter ablation after SBRT with VTs before SBRT.

Methods

We investigated patients that underwent SBRT (a single session of 25 Gy) for refractory VT and subsequent electrophysiology study / reablation for recurrences of VTs. All inducible VTs were analysed concerning morphology and CL.

Results

A total of 9 patients (2 women, aged 60 ± 13 years) were included. Two patients had ischemic heart disease, six patients had nonischemic cardiomyopathy, and one had a cardiac fibroma. All patients were on chronic amiodarone treatment. The mean ejection fraction of the left ventricle was 35 ± 12%. The mean planning target volume for SBRT was 39 ± 21 ml. Electrophysiology study/reablation was performed at a mean interval of 8 months (interquartile range: 2-10months) after SBRT. A total of 23 and 27 distinct VT morphologies were inducible before and after SBRT, respectively. Twelve pairs of VTs (44%) were identified that had identical morphology before and after SBRT. The mean CL of these VT pairs decreased from 399 ± 98 ms to 472 ± 74 ms (P = 0.01) after SBRT. Overall, 15/27 of all VT morphologies induced after SBRT originated from the irradiated region.

Conclusions

Recurrent VTs after SBRT had commonly origin in the irradiated region. In pairwise comparison, the CL of VTs has prolonged after the SBRT. This suggests that SBRT results in radiation-induced fibrosis rather than an increase in conduction velocity.
Subcutaneous implantable cardioverter-defibrillator generator removal: a multicenter analysis
Authors: Luker J , Strik M , Andrade J G , Raymond Paquin A , Elrefai M H , Cano Perez O , Kron J , Schmitt J , Pott A , Veltmann C , Srinivasan N T , Van Stipdonk A , Fluschnik N , Haeberlin A , Steven D
Published: May 2023

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): University Hospital Cologne

Introduction

The subcutaneous implantable cardioverter-defibrillator (S-ICD) was a significant recent advance in sudden cardiac death prevention. Device-related complications, including infection or lead fracture, or changes in the medical status, such as necessity for cardiac pacing, may necessitate device removal. (1) Real-world multicenter data on S-ICD removal are sparse.

Purpose

This multicenter analysis sought to assess the incidence and indications for S-ICD generator removal.

Methods

Retrospective data and the most recent follow-up data on S-ICD devices implanted at 14 participating centers in Europe, the US and Canada, and information on subsequent device removal was submitted to an online database (2). Limited baseline patient information and the incidence of and reasons for S-ICD generator removal or failure were reported. Premature device removal was defined as device removal for any reason other than regular battery depletion (>5 years of longevity).

Results

Data from 1106 devices was analyzed. Devices were implanted between 15.10.2009 and 16.04.2021 at the participating centers. The first-generation model 1010 generator was implanted in 55 (5%), the newer models A209 or A219 were implanted in 457 (41.3%) and 594 (53.7%) respectively.

Patients were aged 46.7±16.1 years and the indication for ICD therapy was primary prevention in 616 (55.7%) and secondary prevention in 484 (43.8%). During the follow-up period, 37 (3%) patients deceased, and 96 patients were excluded from the analysis due to lack of follow-up (<4 weeks).

Premature device removal was performed in 103 (9.3%) during the follow-up period of 31.3±19.5 months. The most common reasons for removal were battery depletion (52%), of which premature, defined as <5 years longevity, depletion accounted for 57%, upgrade to transvenous ICD or CRT (17%) and infection (11%). Other indications for removal included heart transplantation (4%) or ventricular assist device implantation (1.5%), noise detection or inappropriate shocks (6.5%), and patient discomfort (0.7%). (see figure 1)

Regular battery depletion occurred in 34 devices after 69.2±5.3 months. There was no difference in device longevity between the different generator models (1010, A209, and A219).

There were no significant differences between the different generator models with respect to indications for explanation.

Conclusions

In this real-world retrospective multicenter analysis, premature S-ICD generator removal was necessary in 9.3% of patients. Premature battery depletion, infections, and the need for pacing were the most common indications for unplanned generator removal.
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

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<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<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<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

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 <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

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 > 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 > 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 (>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 > 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 <1%, 27% 1-5% and 41% > 5% (Figure). The median HV intervals in patients with VP burden <1%, 1-5% and >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 <1%, 29% of 1-5% and 35% of >5 %. In patients with an HV Interval ≥ 70ms, 25% demonstrated a VP burden <1%, 25% of 1-5% and 50% of >5 %, p=0.64 (Table).

Conclusion

VP burden can be significant in patients with LBBB after TAVR and an HV interval of > 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

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

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 (<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

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: <4.0V/1.0ms; LBBAP: <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<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

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 >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<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 >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.