bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic voltage mapping of the ventricular tachycardia substrate
Authors: Mills M , Grade Santos J , Khanra D , Calvert P , Worthington N , Phenton C , Ashrafi R , Modi S , Todd D , Mahida S , Waktare J , Gupta D , Luther V
Published: May 2024

Background

Substrate mapping techniques that predict ventricular tachycardia (VT) isthmus components in sinus or paced rhythm are necessary as mapping during VT is often not possible. Voltage maps lack accuracy in differentiating scar, traditionally displayed as tissue <0.50mV, from bordering arrhythmogenic substrate. We developed a practical technique aiming to improve the utility of a voltage map during VT ablation, termed ‘Dynamic Voltage Mapping’ (DVM).

Methods

Consecutive patients with post-infarct VT at our centre underwent left ventricle (LV) voltage mapping (mean 4762 points) with Carto3 v.7® and a PentaRay®, or Ensite X® and a HD Grid mapping catheter. Both mapping systems offer algorithms that allow substrate activation maps to be superimposed and analysed on the surface of a voltage display (i.e. Carto Ripple Maps, or Ensite X activation vectors). DVM is a process that sequentially adjusts the voltage display to highlight scar tissue in areas devoid of Ripple bars, or in areas where activation vectors point in multiple unfathomable directions (‘vector disarray’). This approach is summarised in Figures 1 & 2 and was retrospectively performed in all cases. This alternative scar voltage limit was termed the ‘DVM scar threshold’ (mV). Tissue below this threshold was termed ‘DVM-scar’, and tissue immediately surrounding (up to 0.5mV) was termed "DVM-Borderzone (BZ)".

Results

Twenty-five patients (mean age 64.4±11.0 years, 88% male, LV ejection fraction 31.8±6.9%, 16.4±8.5 years since infarct) were studied (n=15 Carto; n=10 EnSite). Across all cases, the mean shell area with voltage <0.50 mV was 36.8±20.3 cm2. The mean DVM scar threshold was 0.24±0.07 mV (Carto: 0.22±0.07 mV [range 0.12–0.35 mV]; EnSite: 0.26±0.08 [range 0.18–0.50 mV]). The mean DVM-scar area was 18.4±14.3 cm2, significantly smaller than the traditional 0.50mV value (p=0.0002). In the 8 patients where stable VT was mapped, the VT isthmus sites co-located within the DVM-BZ in all cases, exemplified in the figures. Pace-mapping at the DVM-BZ matched the remaining unmappable VT morphologies. Ablation lesions were retrospectively superimposed onto the DVM map and generally co-located within the DVM-BZ. No ablation was delivered in tissues >0.5mV. At median follow-up of 8.8 months, VT burden significantly reduced (median 3 episodes in 3-months pre vs. 0 post; p<0.001), with 76% of patients VT-free.

Conclusion

DVM appears to improve the delineation of the post-infarct VT substrate, and is feasible using two commercially-available mapping systems. The mean voltage threshold that differentiated DVM-Scar from BZ tissue was significantly lower than the traditional 0.50 mV scar definition, at 0.24mV, though ranged widely, suggesting that scar thresholds require individualised substrate definition. Targeted ablation of DVM-BZ may be effective at reducing future VT, though requires prospective validation.Figure 1Figure 2
Long-term outcomes of ventricular tachycardia ablation in patients with ischemic and non-ischemic cardiomyopathy: a propensity-score matched analysis
Authors: Gomes D , Sousa Paiva M , Matos D , Rodrigues G , Carmo J , Moscoso Costa F , Galvao Santos P , Carmo P , Bello Morgado F , Cavaco D , Adragao P
Published: May 2024

Background

Catheter ablation (CA) has been shown to be effective in the treatment of ventricular tachycardia (VT). Although some observational data suggest that patients with non-ischemic cardiomyopathy (NCIM) have less favorable clinical outcomes when compared to those with an ischemic etiology (ICM), direct comparisons are scarcely reported. We aimed to compare the outcomes of VT ablation in a propensity score-matched population of ICM or NICM patients.

Methods

Single-center observational registry including 246 consecutive patients with ischemic (ICM, N=166) and non-ischemic cardiomyopathy (NICM, N=80) who underwent drug-resistant VT ablation from 2012 to 2023. A propensity score (PS) was used to match patients in a 1:1 fashion according to the following variables: age, sex, left ventricular ejection fraction (LVEF), NYHA class, electrical storm (ES) at presentation, and previous endocardial VT ablation. The outcomes of interest were VT-free survival and all-cause mortality.

Results

The PS yielded two groups of 71 patients each (mean age 63±10 years, 92.3% male, mean LVEF 35±10%, 35.9% with ES at presentation, and 23.2% with previous ablation), well matched for baseline characteristics. Those with NICM were more likely to undergo epicardial or combined VT ablation (43.7% vs. 9.9%, P<0.001). The procedural complication rate was low (4.9%, N=7) and similar between groups (P>0.05). During a median follow-up of 27 (IQR 15–45) months, patients with NICM had a significantly lower VT-free survival (53.5% vs. 69.0%, log-rank P=0.037), although there were no differences regarding all-cause mortality (22.5% vs. 16.9%, log-rank P=0.245) – Figure. Multivariate analysis identified NICM (HR 2.34 [95% CI 1.32–4.14], P=0.004), NYHA class III/ IV (HR 2.11 [95% CI 1.11–4.04], P=0.024), and chronic kidney disease (HR 2.23 [95% CI 1.25–3.96], P=0.006), as independent predictors of VT recurrence. Non-inducibility of any VT immediately after ablation was associated with significantly lower rates of VT recurrence (22.8%/ year vs. 42.4%/ year, log-rank P=0.03).

Conclusion

NCIM patients are at increased risk of VT recurrence after ablation, although long-term mortality was similar to ICM in a propensity-matched cohort. Non-inducibility of any VT after CA is associated with better outcomes.Figure
Cardiac magnetic resonance - aided ventricular tachycardia substrate ablation
Authors: Letsas K , Saplaouras A , Mililis P , Kariki O , Dragasis S , Patsiotis I , Efremidis M , Nyktari E
Published: May 2024

Objectives

To assess feasibility and reliability of Cardiac magnetic resonance (CMR)-derived pixel signal intensity (PSI) maps obtained by Three Dimensional (3D)- Late Gadolinium Enhancement (LGE) images for detecting potential targets for VT substrate ablation procedures.

Background

Parametric imaging with color-coded PSI maps obtained from pre-ablation 3D LGE -CMR imaging can be used for identification and characterization of arrhythmic abnormal substrate. Recent publications have shown that PSI maps permit visualization of border zone areas inside the scar. Specifically, corridors of viable tissue within the scar connecting healthy myocardium define VT corridors that may be the electrical equivalent of the abnormal conducting channels on the electroanatomical mapping (EAM).

Methods

8 patients with scar-dependent monomorphic VTs who underwent 3D-LGE CMR imaging prior to substrate ablation were included in the study. The studies were performed at 1.5T scanner. We obtained two data sets of 3D whole heart LGE imaging with high resolution. Patients underwent two acquisitions: the conventional respiratory navigated, electrocardiographically-gated 3D fast gradient echo (1.3slice thickness, 256x256 matrix acquisition) and the image-navigated isotropic high resolution 3D GE with Dixon water-fat separation.

3D LGE-CMR images were processed with ADAS-VT software to produce a 3-dimensional model of the heart with 10 layers from the endocardium to epicardium and PSI maps color-coded from the LGE data projected to each of the shells (Figure 1). In the LGE-CMR PSI maps, VT corridors were obtained automatically by the ADAS VT software. Subsequently, data were given to the electrophysiologists and merged with the CARTO3 system EAM data obtained for the ablation (Figure2). CMR information was used to facilitate the identification of target ablation sites in the areas identified by CMR as abnormal substrate and radiofrequency was applied in the presence of both a pathological electrogram (EGM) and a VT corridor as identified by CMR.

Results

There was a 95% agreement between the abnormal conducting channels as detected by abnormal electrograms in the EAM and the VT corridors identified by 3D LGE CMR imaging. In two occasions, there was one VT corridor that did not correlate with abnormal electrograms and was not ablated. The two 3D LGE sequences used for ADAS-VT corridors analysis showed complete agreement in the number and location of VT corridors. Mean acquisition time for 3D LGE imaging was 11±4minutes for the conventional fast gradient echo sequence, and 5±2minutes for the novel 3D self-image navigated LGE sequence. The image quality of 3D LGE was superior with the Dixon fat-water separation. Overall CMR-aided VT ablation reduced the procedural and fluoroscopy time by 40%.

Conclusions

CMR-aided VT ablation is feasible, reliable and significantly reduces the procedural time.
Correlation between ventricular local impedance and tissue composition by MRI in chronic infarction
Authors: Aranyo Llach JÚL IA , Martinez-Falguera D , Teis A , Fadeuilhe E , Rodriguez-Leor O , Bazan V , Sarrias A , Villuendas R , Curiel C , Bayes-Genis A , Galvez-Monton C , Bisbal F
Published: May 2024

Background

Local impedance (LI) mapping is feasible and provides additional tissue characterization of the ventricular tachycardia substrate. Data on tissue composition underlying different LI values are lacking.

Purpose

To correlate LI with tissue composition evaluated by magnetic resonance imaging (MRI) in a chronic myocardial infarction (MI) swine model.

Methods

One-month after a non-reperfused anterior MI, eighteen Landrace X Large White pigs underwent delayed-enhancement MRI (deMRI) and endocardial LI mapping. deMRI images were post-processed off-line with commercially available dedicated software; scar subtypes (with thresholds set at 40-60% of maximal pixel signal intensity [PSI]), border-zone corridors and left ventricular wall thickness were measured. LI thresholds were set using the blood-pool LI value to define low, intermediate, and high tissue resistance subtypes. LI maps were co-registered with deMRI for analyses.

Results

Low LI zones correlated with deMRI dense and transmural scar (exhibiting endo and epicardial PSI >60% in 91% and 80% of the cases, respectively). Intermediate LI tissue exhibited predominantly subendocardial scar with more heterogeneous composition (8%, 47% and 45% of the points had <40%, 40-60% and >60% endocardial PSI, respectively), and with less epicardial involvement (50% of points had epicardial PSI <40%). Border-zone corridors co-localized with intermediate LI tissue in most of the cases (77%). Low LI zones exhibited more pronounced wall thinning compared to intermediate LI tissue (p<0.001) (Figure 1).

Conclusions

LI correlated with scar density and transmurality on deMRI. Areas of low LI had higher proportion of dense, transmural scar and wall thinning compared to intermediate LI areas. MRI-detected border-zone corridors colocalized with intermediate LI in most cases.LI and deMRI data (endo and epi scar)LI and deMRI data (tissue thickness)
Predictors of improvement in LV ejection fraction post PVC ablation
Authors: Nather A , Begley D , Martin C A , Fynn S P , Heck P M , Zachariah D , Virdee M S , Mellor G , Gajendragadkar P , Agarwal S
Published: May 2024

Introduction

Premature ventricular contraction (PVC) is a frequently encountered finding in routine ECGs, that in certain individuals may be followed by reduction in ejection fraction (EF). This may be improved or even reversed with a medical or interventional reduction of ectopic burden.

Objective

The primary objective of this study is to assess the potential effectiveness of cardiac ablation in suppressing PVC and subsequently enhancing the EF. Further we aim to establish predictive factors of the success of the intervention.

Methods

In a retrospective data analysis at a single medical centre, we examined records of 116 patients who underwent ectopic ablation, with 10 patients having more than 1 ablation. Demographic information, heart-related conditions along with the presence of a scar on MRI, was collected. The study also recorded pre- and post-procedure PVC burden and EF measurements.

Results

Demographics and procedural details are in table 1. It was found that patients participating in this study were predominantly male (66.4%), on average 60.1 (± 13.6) years old, overweight (BMI 29.8 ± 5.4) with no additional heart disease (56%) and no scarring on MRI (55%).The PVC burden before ablation (27.9 ± 12.7) significantly reduced to 8.0 ± 11.2 post-ablation (p < 0.005), marking an average relative reduction of 68.1% (± 44.1%). Successful interventions, defined by a reduction exceeding 50%, were observed in 79% of patients. The EF increased from 39.6 ± 8.9 to 47.5 ± 10.7 post-ablation (p < 0.005), corresponding to an average increase by 8.4 ± 8.5. Notably amongst the patients who had a successful ablation, 36% of patients achieved normalized EF (>55%) and 42% showed an improvement of at least 5%. A strong correlation emerged between the relative change in PVC and the ejection fraction measured after ablation, with an increase by 0.10 for every percent reduction (p < 0.00). The relative increase in the EF% was significantly higher in patients where the PVC burden was reduced by at least 50% (figure 1).

Linear fixed effect modelling explored the influence of patient characteristics on the model. Patients with higher BMI had a lower EF after ablation with same relative reduction in PVC (p < 0.03). Similarly, a scar on MRI and associated heart condition was associated with reduced improvement in ejection fraction (p < 0.02). Also, for every increase in age patients had a reduction of 0.2 EF after ablation (p < 0.01). Right heart PVC’s were ablated more successfully, and had higher EF post ablation (p < 0.01).

Conclusion

In conclusion, reduction in PVC burden increases the EF after treatment. Increasing BMI, age and presence of associated heart disease can negatively impacted LVEF post ablation. Further research could improve the model that predicts improvement in LV function post successful PVC ablation.Figure 1Table 1
Tissue composition underlying local impedance in chronic infarction: an histological study
Authors: Aranyo J , Martinez-Falguera D , Teis A , Fadeuilhe E , Rodriguez-Leor O , Bazan V , Sarrias A , Villuendas R , Bayes-Genis A , Galvez-Monton C , Bisbal F
Published: May 2024

Background

Local impedance (LI) mapping is feasible and provides additional tissue characterization of the ventricular tachycardia (VT) substrate. VT isthmuses are usually located in areas of intermediate LI while low LI regions did not actively participate in the VT circuit. Histological studies evaluating the tissue composition underlying different LI values are lacking.

Purpose

To describe the tissue composition underling different LI subtypes in a chronic myocardial infarction (MI) swine model.

Methods

One-month after a non-reperfused anterior MI, five Landrace X Large White pigs underwent endocardial LI mapping (figure 1). LI thresholds were set using the blood-pool LI value to define low, intermediate, and high tissue resistance subtypes. A navigated needle-catheter was used to inject methylene-blue at sites with intermediate and low LI to guide the ex vivo tissue localization. Tissue was obtained for further histological analysis. Low and intermediate LI zones were analysed.

Results

A total of six and eight samples were analysed for low and intermediate LI, respectively. Compared to low LI zones, intermediate LI tissue displayed less Collagen I (1.03±0.26 vs. 0.34±0.35%, p=0.0082), Collagen III (9.92±2.98 vs. 6.47±1.80%, p=0.0380) and Collagen Volume Fraction (10.92±2.77 vs. 6.81±1.92, p=0.0163), without differences in the overall fibrotic and adipocytic deposition (figure 2). No significant differences in the Cx43, CTnI and SERCA2 expression were observed.

Conclusion

LI subtypes showed distinctive histological composition. Intermediate LI sites displayed less collagen content (I, III and collagen volume fraction) compared to those with low LI.Endocardial LI mappingHystological analysis: Collagen Content
Substrate characterization and outcomes of ventricular tachycardia ablation in amyloid cardiomyopathy: a worldwide study
Authors: Compagnucci P , Dello Russo A , Gasperetti A , Schiavone M , Sehrawat O , Hasegawa K , Mohanty S , Liang J , Stevenson W , Tondo C , Siontis K , Tandri H , Santangeli P , Natale A , Casella M
Published: May 2024

Background

the electrophysiological substrate underpinning ventricular tachycardia (VT) in cardiac amyloidosis (CA) remains elusive, and outcomes of catheter ablation in this peculiar population are currently unknown.

Purpose

we sought to describe the electrophysiological substrate and clinical outcomes of VT ablation in a cohort of patients with CA.

Methods

we included 19 consecutive patients (mean age, 69±10 years; male sex, 89%) with CA (ATTR, n=13; AL, n=6) undergoing catheter ablation for VT/ventricular fibrillation (VF) between 2013 and 2023 in a retrospective, observational, international study, involving 7 referral European and North American electrophysiology units. The primary efficacy outcome was recurrent VT/VF during follow-up, while the primary safety outcome included major procedure-related adverse events.

Results

the indication for ablation was drug-refractory VT in 16 patients (84%), and PVC-initiated polymorphic VT/VF in 3 (16%). Catheter ablation was performed using endocardial (n=14, 74%) or endo-epicardial approaches (n=5, 26%). Complete endocardial electroanatomical voltage maps of the left and right ventricles were obtained in 14 (74%) and 6 (32%) patients, respectively. Each patient had evidence of low-voltage areas, most commonly involving the interventricular septum (n=12); late potentials were recorded in 13 patients (68%). A median of 1 (1-2) VTs were inducible per patient; in 10 subjects (43% of mappable VTs), activation mapping was consistent with septal VT origin. Complete procedural success was obtained in 13 patients (68%), at the expense of 4 (21%) major procedure-related adverse events. After a median follow-up of 36 (18-54) months, sustained VT/VF recurrence was observed in 9 patients (47%); survival free from VT/VF recurrence was 74% (95%CI, 56-96%) at 12 months, and 53% (95%CI, 34-94%) at 36-month follow-up; the majority of patients remained on antiarrhythmic drugs (Figure). Low-voltage QRS (HR,21.96; p=0.022) and complete procedural success (HR,0.08; p=0.029) were associated with recurrent VT/VF at multivariable analysis (Figure).

Conclusions

catheter ablation of VT/VF is associated with favorable acute and mid-term arrhythmia control, yet with substantial risk of procedure-related complications and long-term recurrences. Septal substrate and frailty challenge successful management of patients with CA and VT/VF.Multimodality evaluation of LV substrateMain Study Outcomes
Clinical accuracy of a 3-dimensional multielectrode non-invasive ECG mapping vest in premature ventricular contraction ablation procedures
Authors: Besiroglu F , Pluta S , Lenarczyk R , Hunuk B , Sokal A , Kowalski O , Kalarus Z
Published: May 2024

Background

Invasive 3D mapping is the current gold standard in determining premature ventricular contraction (PVC) localization. However, given its invasive nature, unawareness of PVC origin beforehand may lead to prolonged procedure times and increased complications risk.

Purpose

In this study, we compared the diagnostic accuracy of a non-invasive 3-dimensional mapping ECG vest (MECGV) with invasive 3D mapping and ablation successful points as a reference. We also evaluated 12-lead ECG based pre-procedural PVC localization accuracy of 2 expert operators blinded to clinical findings.

Methods

In 15 consecutive adult patients between the ages of 35 to 69 (male n: 9, median age: 48), MECGV and subsequently a 3D mapping with uneventful successful PVC RF catheter ablation were performed and included in the study. PVC localization estimations of MECGV method and the EP experts' locatization predictions were compared separately with invasive 3D ablation results using the Cohen's kappa method and with the help of a 16-segmentation model we created for the ease of the analyses .

Results

Results were presented on Table-1. MECGV was found to be highly compatible (Cohen's kappa 0.968, p<0.001) with the RF ablation results. However operators assessments were found to be less coherent with invasive 3D mapping (Operator 1 Cohen's kappa 0.571, p 0.033, Operator 2 Cohen's kappa 0.618, p: 0.019, respectively). MECGV accuracy was %87 in pinpointing the PVC focus. The only 2 localizations that MECGV failed were on the septal aspects of the heart (Picture-2 Failure of defining the focus on LVOT septal instead of RVOT septal)

Conclusion

MECGV method seems to be highly compatible with invasive 3D mapping techniques in detection of PVC localization and bests EP expert estimates in this regard. However, it also seem to have some pitfalls especially on septal aspects of the heart.Table-1 and segmentation schemePicture-1
Ventricular tachycardia initiation patterns on electrograms of implantable defibrillator devices
Authors: Ganeswaran T , Monkhouse C , Orini M , Walker A , Srithar K
Published: May 2024

Introduction

Sudden cardiac death is an unexpected death from a cardiac origin attributed by arrhythmias such as ventricular fibrillation (VF) and ventricular tachycardia (VT). The predominant treatment to terminate VT and VF is the implantation of an implantable cardioverter defibrillator (ICD). Currently, VT initiation in specific and small cohorts such as structural heart disease and reduced left ventricular ejection fraction patients have been explored. However, there is limited literature comparing the association between VT initiation patterns and defibrillators therapy outcome. This study aimed to investigate the most prevalent type of VT initiation from stored electrograms on ICDs and to explore the association between VT initiation pattern and therapy outcome (i.e., the ability to terminate VT).

Method

344 stored electrograms amongst 65 patients from an existing database were visually inspected to classify VT initiation pattern as sudden onset (not preceded by premature ventricular complexes), non-sudden onset (preceded by premature ventricular complexes) and pacing-induced (device induced). Wilcoxon rank sum and Fisher’s Exact tests were used to assess differences between these groups. Mixed-effect logistic regression models accounting for multiple events occurring in individual patients were used to investigate association between the VT initiation pattern and therapy outcome.

Results

The mean age for the study group was 53±20 years and 54 (83%) subjects were males. Aetiology includes: 29 ischemic heart disease (45%), 10 hypertrophic cardiomyopathy (15%), 8 dilated cardiomyopathy (12%) and 18 other conditions (28%). Non-sudden onset VT (51%) was the most prevalent type of VT initiation pattern on defibrillators followed by sudden onset (44%) and pacing induced (5%). Non-sudden onset was 3 times more likely than the other 2 groups combined to be associated with unsuccessful therapies with an OR: 3.05 (95% confidence interval: 1.14, 8.15); p =0.03. There was no association between pacing-induced onset and unsuccessful therapies with an OR: 0.33 (95% confidence interval: 0.03, 3.33); p = 0.35. No association was identified for any of the three initiation patterns versus the other two combined and unsuccessful therapies when mixed-effect models were constructed.

Discussion/ Conclusion: This study is consistent with other findings showing that non-sudden onset (51%) is the most prevalent VT onset. Pacing-induced VT accounted for 5% of VT with the predominant reason for initiation being undersensing of R-waves leading to pacing on the T-wave. This study reiterates the importance of programming strategies to prevent pacing induced VT. No associations were found with VT initiation and therapy outcome with mixed-effect models, possibly due to pseudo-replication being a limitation of this study. Prospective studies should be carried out in future to attempt to maximise success rate and establish the most effective treatment in ICDs.
Short- and long-term patient-reported outcomes of subcutaneous implantable cardioverter-defibrillator therapy
Authors: Bisignani A , Bisignani G , Palmisano P , Bianchi V , La Greca C , Tola G , Nigro G , Caravati F , Mascia G , Rordorf R , Notarstefano P , Valsecchi S , Lovecchio M , Bianchi S
Published: May 2024

Background

The safety and efficacy of subcutaneous implantable cardioverter-defibrillator (S-ICD) therapy are well-established. However, there is a paucity of patient-reported outcome data, despite the increasing emphasis on incorporating patients' perspectives into quality care assessments. Current guidelines also recommend evaluating psychological status and addressing distress in defibrillator patients.

Purpose

This study aims to assess perioperative and postoperative pain during S-ICD implantation, along with patient acceptance during follow-up. We also explore associations between these outcomes, clinical characteristics, and implantation variables.

Methods

A total of 149 consecutive patients (87% male, mean age 53±13 years, body mass index 27±4 Kg/m², ejection fraction 39±14%) who underwent S-ICD implantation across 11 centers were analyzed. Short-term endpoints included pain during and 6 hours after the procedure. Pain intensity was rated on a 10-point visual analogue scale. Long-term endpoint was S-ICD patient acceptance measured (on a 0-to-100 point scale) by the Florida Patients Acceptance Survey (FPAS) score and its components: Return to Function (RTF), Device-Related Distress (DRD), Positive Appraisal (PA), and Body Image Concerns (BIC). The survey was administered 12 months post-implantation.

Results

The S-ICD generator was positioned in an intermuscular pocket in 140 (94%) patients. Serratus anterior plane block (SAPB) was performed in 103 (69%) patients. 72 (48%) patients underwent the defibrillation testing. Implantation success was reported in all patients without operative complications. Overall, pain intensity during implantation was 2 [25th-75th percentile: 1-4], and 1 [1-2] for static pain and 2 [1-3] for dynamic pain, 6 hours post-procedure. SAPB was associated with significantly lower pain intensity during implantation (2 [1-3] vs. 4 [2-5], p<0.001) and non-significantly lower values of dynamic pain intensity 6 hours post-procedure (1 [1-2] versus 2 [1-3], p=0.076). The other tested variables, i.e. age, sex, body habitus, ejection fraction, omission of defibrillation testing, were not associated with different pain levels. S-ICD acceptance scores were favorable overall (total FPAS 77 [63-87], RTF 69 [56-88], DRD 25 [10-45], PA 88 [75-100], BIC 13 [0-38]). Patients who underwent SAPB exhibited better RTF (75 [56-88] versus 63 [50-69], p=0.002) and PA (88 [75-100] versus 75 [69-94], p=0.004).

Conclusions

S-ICD implantation resulted in minimal discomfort, especially with novel anesthetic techniques. Overall, patients reported good acceptance of the S-ICD. Improved acceptance was observed in patients who underwent SAPB, highlighting the significance of enhanced patient implantation experience for long-term outcomes.
When to implant an ICD in patients with heart failure and reduced ejection fraction? Insights from the HF-OPT trial
Authors: Veltmann C , Duncker D , Doering M , Gummadi S , Robertson M , Wittlinger T , Colley B J , Perings C , Jonsson O , Bauersachs J , Sanchez R , Maier L
Published: May 2024

Background

In patients with de novo heart failure with reduced ejection fraction (HFrEF) improvement of left ventricular ejection fraction (LVEF) is expected to occur when started on guideline-recommended medical therapy (GRMT). However, the period of time, when LVEF improvement is completed, is unknown.

Purpose

Evaluation of improvement of LVEF >35% within the first year after de novo diagnosis of HFrEF with severely reduced LVEF <35%.

Methods

In the prospective HF-OPT-trial, patients with de novo HFrEF and LVEF ≤35% prescribed the wearable cardioverter defibrillator (WCD) were enrolled and followed up to one year. GRMT was initiated and uptitrated according current guidelines. LVEF improvement >35% under GRMT was echocardiographically assessed at day 0, day 90, day 180 and day 360.

Results

A total of 487 patients (59 years (IQR: 51-68), 27% women) were followed until day 180. Out of 487 patients 392 patients were followed additionally to day 360. Dosages of GRMT were significantly increased during follow-up (p<0.001) At 90 days, 46% (CI: 41%-50%) of the patients had LVEF improvement >35%. About half of those with persistently LVEF<35% at day 90 (46%, CI: 40%-52%) had LVEF improvement >35% by day 180, increasing the total rate of improvement >35% to 68% (CI: 63% - 72%). Until day 360 the rate of LVEF improvement >35% increased to 78%.

Conclusions

78% of patients with de novo HFrEF showed improvement in LVEF >35% during the first year after diagnosis following GRMT. This finding impacts decision making for primary preventive ICD implantation.Development of LVEF.
Outcomes of leadless pacemaker in chronic kidney disease patients: real-world data from the i-LEAPER registry
Authors: Mitacchione G , Schiavone M , Arabia G , Gasperetti A , Palmisano P , Mazzone P , Rovaris G , Dello Russo A , Biffi M , Di Biase L , Chierchia G B , Della Bella P , Tondo C , Curnis A , Forleo G B
Published: May 2024

Background

Chronic kidney disease (CKD) represents a major risk factor for patients requiring transvenous pacemaker (TV-PM), resulting in a high rate of operative complications and PM-related infection rate (21.9% and 12.5%, respectively), with both complications parallels to severity of CKD. Moreover, TV leads represent an important concern for end-stage CKD patients, often needing vascular access patency for renal replacement therapy. In this setting leadless pacemakers (LPMs) represent an attractive alternative to TV-PM for their lower device-related infection rate and the absence of TV leads. To date, limited data on LPM safety and efficacy profile in CKD patients are available.

Purpose

to assess operative and long-term safety and efficacy of LPMs implantation in patients with different stages of CKD in the real-world setting.

Methods

Consecutive patients who underwent LPM implantation in 12 European centers joining the i-LEAPER registry were retrospectively enrolled. CKD stage was assessed according to CKD-EPI equation for eGFR. Patients with CKD stage G3a/b (N=245) and stage G4/G5 (N=67) were compared with patients with normal kidney function (NKF) (N=867). Primary safety endpoint was LPM-related major complications rate at implant and during follow-up (FU). Additionally, the rate of patients showing sub-optimal electrical performance (pacing threshold [PT] >1V@0.24ms) was compared between groups.

Results

1179 patients were enrolled and followed for a median of 33 [IQR 24-47] months. When compared with the NKF group, patients with CKD stage G3a/b and stage G4/G5 showed a higher burden of cardiovascular comorbidities (Table 1). The choice of a LPM was mainly due to vascular concern in the CKD stage G4/G5 group, while a perceived highest infective risk was reported in CKD stage G3a/b group (Table 1). Major complication rate at implant and during FU did not differ between groups, regardless of renal impairment stage (Table 2). All-cause mortality incidence resulted higher in CKD stage G4/G5 group when compared with NKF group (17.9% vs 6.8%; HR 4.24; 95%CI 4.25-7.94, p<0.001) (Figure A). The rate of patients with PT>V1@0.24ms during FU did not differ between groups, not exceeding 13.8%, and therefore remaining consistent with historical data for LPM (Figure B).

Conclusion

In the real-world setting, LPM showed a remarkable safety and efficacy profile in CKD patients regardless of renal impairment stage that was comparable to NKF population. LPM should be considered as first choice in CKD patients requiring a PM.
Serial GLS assessments over time in patients with preserved ejection fraction undergoing permanent cardiac pacemaker placement
Authors: Sung Soo K I M , Hyung Ki J , Hyun Kuk K I M , In Young C H O I , Young Jae K I , Dong Hyun C H O I , Keun Ho P A R K
Published: May 2024

Background

Chronic right-ventricular (RV) pacing can exacerbate heart failure in patients with a low ejection fraction (EF), but little is known about pacing-induced cardiomyopathy (PICM) in patients with preserved EF. We aimed to investigate risk factors of PICM in these patients during long-term follow-up.

Methods

The prospective registry at our University Hospital, South Korea, included de novo patients with preserved EF undergoing transvenous permanent pacemaker (PPM) implantation for atrioventricular blockage from 2018 to 2022. Patients with EF > 50% and expected ventricular pacing > 40% were included. All patients were followed with serial echocardiography (preimplant, post implant, 12 months). All patients enrolled in this study were seen as outpatients every 3–6 months. Composite outcomes were cardiac death (pump failure), hospitalization because of heart failure, PICM, and biventricular pacing (BVP) upgrade.

Results

71 patients (28 men, 73.1 ± 9.5 years) were included. After PPM implantation, EF and GLS were significantly decreased. During three years of follow-up, 2 patient died, 6 were hospitalized, 7 suffered PICM, and 3 underwent BVP upgrade. Cox regression analysis identified reduced post-implant global longitudinal strain (GLS) (HR, 1.524; 95% CI, 1.149–2.021; P = 0.003) as independent predictors of PICM. Post-implant GLS showed high predictive accuracy for PICM, with an area under the curve of 0.92 (95% CI 0.829–0.971; P < 0.001)

Conclusion Post-implant GLS, rather than pre-implant GLS could help identify individuals at high risk of PICM. After PPM implantation, it is important to measure GLS, and patients with reduced GLS should be monitored more frequently and echocardiographic surveillance, with a view to an upgrade to BVP.Serial EF and GLS assessmentGLS ROC curve
Reduction in pacemaker rates post-heart transplantation with use of organ preservation systems
Authors: Cherrett C , Adonopulos A , Phan J , Lee W , Walker B , Jansz P , Subbiah R , Macdonald P
Published: May 2024

Background

Approximately 10% of heart transplant recipients require permanent pacemaker (PPM) implantation. (1) Prolonged graft ischaemic time may contribute to conduction system injury and PPM requirement. (2) Ex-vivo preservation of heart allografts at the time of organ retrieval, using either normothermic or hypothermic organ preservation systems (OPS), allows for the reduction of graft ischaemic time which can facilitate long-distance procurements and use of marginal donors including donation after circulatory death (DCD) donors. (3)

Purpose

We sought to determine if the use of organ preservation systems reduced PPM implantation in heart transplant recipients.

Methods

This was a single-centre retrospective study of 405 consecutive heart transplant recipients between July 2014 and March 2023. Baseline demographics, utilisation of organ preservation systems, donor ischaemic times, history of graft dysfunction, rejection and chronic allograft vasculopathy were obtained from the medical records. The primary outcome was PPM implantation.

Results

Of 405 heart transplants performed, an organ preservation system (OPS) was utilised in 118 (29.1%) patients. Normothermic OPS was used in 93/405 (23%) transplants, 90 of which were DCD transplants. Twenty-five of 405 (6.2%) transplants were performed using a hypothermic OPS to facilitate donation after brain death (DBD). The remaining 287 (70.9%) organs underwent cold ischaemic storage (CIS) from retrieval until transplant. Apart from male sex (81% in OPS group versus 69% in the CIS group), there were no significant differences in baseline demographics between the two groups (table 1).

Two of 118 (1.7%) patients in the OPS group required PPM implantation, compared to 27/287 (9.4%) in the cold ischaemic storage group (Chi-Square 7.5, p = 0.006). Kaplan-Meier analysis (figure 1) demonstrates a significantly lower rate of PPM implantation in the OPS arm (Log Rank 6.975, p = 0.008). Of the 29 patients who required pacing, 12/29 (41.4%) had AV block and 17/29 (58.6%) had sinus node dysfunction. Thirteen of 29 patients (44.8%) required PPM implantation within 30 days of transplant. Six of 29 patients (20.7%) were pacing dependent at last follow up.

Conclusion

Heart transplants performed utilising an organ preservation system were associated with lower PPM rates.Table 1.Figure 1.
Electrocardiogram predictors of leadless pacemaker implantation in the right ventricular free wall
Authors: Goto K , Miyazaki S , Negishi M , Ikenouchi T , Yamamoto T , Kawamura I , Nishimura T , Takamiya T , Tao S , Takigawa M , Sasano T
Published: May 2024

Background

Leadless pacemakers (LLP) carry the potential risk of cardiac injury, especially when implanted in the free wall of the right ventricle.

Purpose

To investigate the ECG criteria for distinguishing free wall implantation of LLP, further clarification is needed.

Methods

We conducted a retrospective study involving 17 patients who underwent LLP implantation, followed by chest computed tomography to confirm the implantation site. Patients were categorized into three groups based on the location of implantation (septum [Sep], apex [Apex], and free wall [FW]), and we compared the morphology of the 12-lead ECG during LLP pacing.

Results

Among the implantation sites, nine were in the Sep (52.9%), five in the Apex (29.4%), and three in the FW (15.8%). In terms of pacing QRS morphology, the FW group exhibited significantly longer QRS duration (Sep: 145.6±15.2 vs. Apex: 161.6±3.6 vs. FW: 175.3±16.6, P<0.01), a notched QRS complex in lead III (Sep: 0.0% vs. Apex: 0.0% vs. FW: 100.0%, P<0.01), and a shorter peak deflection index (PDI) in lead V1 (Sep: 0.59±0.07 vs. Apex: 0.55±0.06 vs. FW: 0.40±0.02, P<0.01) than the other two groups. Receiver operating curve analysis to predict FW implantation revealed that a PDI of 0.42 in lead V1 (Area under the curve [AUC]=1.00, specificity=100.0%, sensitivity=100.0%, P<0.01) and a QRS duration of 173 msec (AUC=0.89, specificity=100%, sensitivity=66.7%, P<0.01) were the optimal cutoff values.

Conclusion

The LLP FW implantation group had a longer QRS duration, a notched QRS complex in lead III, and a shorter PDI in lead V1 compared to the other pacing sites.
Feasibility and safety of permanent left bundle branch area pacing in pediatric patients
Authors: Bakytzhanuly A , Turubayev E , Bagibayev S , Esilbayev Z H , Talgatova S , Yuldashev S , Nuralinov O
Published: May 2024

Introduction

Left bundle branch area pacing (LBBAP) is a promising pacing strategy with a low and stable pacing threshold. It maintains electrical and mechanical synchronization of the ventricles. Conduction system pacing (CSP) has evolved rapidly to become the pacing method of choice for many adult and pediatric patients. Recent studies have begun to demonstrate the feasibility and efficacy of CSP in pediatric patients. Nowadays, research articles about LBBAP in children are comparatively rare, therefore, research in this area is preferred. Limited data on LBBAP in pediatric patients (≤ 18 years old) are available.

Purpose

This study aims to describe the feasibility and safety of LBBAP in pediatric patients.

Methods

This study includes 4 patients: 1 male, and 3 females, respectively. The average age of the patients was 15.5±1.9 years and the weight was 51,5±17,6 kg. All patients were diagnosed with 3rd-degree atrioventricular (AV) block, in one case the total AV block occurred after previous radiofrequency ablation of the parahisian and right lateral accessory pathway. One patient had previously been implanted with an epicardial pacemaker and presented to our clinic with ventricular lead dysfunction. Pacing parameters were assessed during implantation, the next day after the procedure, and 1, 3 months follow-up. Echocardiography was performed to evaluate LV function and assess the approximate lead location and impact on tricuspid valve function.

Results

LBBAP was successfully achieved in all patients resulting in narrow QRS complexes (102±12.7ms) and right bundle branch block QRS morphology. To confirm left bundle branch area capture, peak left ventricular activation time (pLVAT) (84.5±4.1ms), V6-V1 (43.5±2.5ms) inter-peak interval, presence of left bundle potential, transition from non-selective to selective capture were recorded at during the implantation. The mean paced QRS duration was (108±13 ms). Pacing threshold and impedance remain stable (0.75±0.25V, and 615±50 Ohm, respectively). There was no major complication during the implanting process and follow-up.

Conclusions

LBBAP can be performed safely in children with narrow QRS complexes and can achieve stable pacing parameters.
Leadless pacemaker implantation following tricuspid interventions: multicenter collaboration of feasibility and safety
Authors: Gul E , Waldmann V W , Baudinaud P B , Sabbag A S , Jubeh Y J , Clementy N C , Bisson A B , Ollitraut P O , Conti S C , Carabelli A C
Published: May 2024

Background

Permanent pacing is often required following valve intervention (either surgical or percutaneous), however tricuspid interventions pose specific challenges to conventional pacing.

Therefore, leadless pacemaker (LP) implantation may be the preferred strategy when permanent pacing is required after tricuspid valve intervention.

Objective

To report periprocedural outcomes and follow-up of patients undergoing implantation of a LP system following tricuspid valve interventions.

Methods

Consecutive patients with previous tricuspid valve intervention at the time of attempted implantation of a LP were included.

Results

Between 2019 and 2022, 40 patients underwent LP implantations following tricuspid interventions in 5 large tertiary centers. The mean age was 68.9 ± 13.7 years, and 48 % patients were male. The indication for pacing was as following: AVB in 27 (68%) patients, AF with slow ventricular response in 10 (25%) patients, and refractory rapid atrial fibrillation (AF) referred to AV junction ablation in 3 (7%) patients. Most of the patients received Micra VR (78 %). Procedure was successful in all patients. Mean procedural time of 58 ± 32 min and median fluoroscopy time of 7.5 min. Electrical parameters were within normal range (threshold: 1.35 ± 1.2 V@0.24 ms, impedance: 772 ± 245 Ohm, R-wave: 6.9 ± 5.4 mV). No acute complications were observed. During a mean follow-up of 10 months, electrical parameters remained stable, and 4 deaths were occurred (not related to the procedure).

Conclusion

A LP is safe and efficient option following tricuspid valve interventions.Micra LP in a patient with bioprostheticMicra LP in a patient with tricuspid rin
Effect of implantable cardioverter defibrillator intracardiac electrogram morphology changes on hospitalization and life quality
Authors: Ozkahya M , Yilancioglu R Y , Turan O E , Ozcan E E
Published: May 2024

Background

Implantable Cardioverter Defibrillators (ICD) are standard therapy for patients at risk of life-threatening ventricular tachyarrhythmias. ICDs use morphology discrimination to compare ventricular electrogram during tachycardia with reference template during baseline rhythm. Baseline morphology match score (MMS) changes may predict arrhythmic events, but usefulness as a parameter for heart failure (HF) is still unknown.

Methods

The prospective single-center study included consecutive 88 patients undergoing device control at cardiology department from July 2022 to May 2023. Inclusion criteria were patients implanted with ICD or CRT for at least 3 months; the exclusion criteria were defined as communication barriers (n=1), depleted device battery during checks (n=1), total AV block (n=3), and auto-template activation (n=4). The data were analysed for changes in the baseline (MMS) relationship with demographic, clinical characteristics, quality of life (QOL), and hospitalisation with HF.

Results

We analyzed 79 patients with a mean age 64,9 13,6 and an average MMS of 98 1,8 morphology. During follow-up there were 12 (15%) patients hospitalized due to HF. ROC curve analysis showed that a MMS ≤ 97% had 73% sensitivity and 59% specificity for hospitalization (p: 0,033 Area 0.695). No significant differences were observed in demographics between the two groups. Although there was no significant difference in EF and BNP levels, patients with MMS <97% had lower QOL scores and more hospitalizations for heart failure (HF).

Conclusion

EGM baseline MMS changes in ICD were associated with hospitalization for HF and QOL, apart from arrhythmia detection indications. It may be a follow-up parameter for HF, in addition to the current device algorithms.Graphical AbstractTable 1
Substernal lead removal: experience from the EV ICD pivotal study
Authors: Amin A , Crozier I , Murgatroyd F , Boersma L V A , Manlucu J , Knight B P , Leclercq C , Birgersdotter-Green U M , Chan J Y S , Roukoz H , Biffi M , Sagi V , Wiggenhorn C , Friedman P
Published: May 2024

Background

The extravascular implantable cardioverter defibrillator (EV ICD) has recently emerged as a new option for guideline indicated ICD patients. Previous study results from the EV ICD Pilot and Pivotal studies have demonstrated that the device can provide safe and effective therapy through chronic follow up. However, less has been reported regarding EV ICD lead removal.

Purpose

To report on the experience of lead removal in the EV ICD Pivotal Study.

Methods

The EV ICD Pivotal study was an international, prospective, single-arm, premarket clinical study. Patients with a class I or IIa indication for a single-chamber ICD per ESC or ACC/AHA/HRS guidelines were enrolled. Lead removal summary data was reported.

Results

Of 316 patients with an implant attempt, (74.7% male, age 53.8±13.1 years, 82% primary prevention, LVEF of 38.9%±15.4%, and NYHA Class I [23.7%] or II/III [65.5%]) 299 were fully implanted; 17 (5.7%) of which had a lead removal procedure (14–752 days post-implant, at 13 sites) with 3 of them having been implanted for more than 1 year. Reasons for lead removal were lead dislodgement (n=7), infection (n=5), high impedance alert due to lead fracture (n=2), pacing indication (n=1), cardiac transplant (n=1), or scheduled sternotomy (n=1). New EV ICD leads were placed in 7/17 (41.2%) patients. No serious adverse events were adjudicated as related to the explant procedures. There was a single observation of incision site haemorrhage, that was resolved with wound care. Additional details on lead removal will be included at the time of presentation.

Conclusions

The EV ICD lead was successfully removed 14-752 days post implant. Nine patients were re-implanted with either extravascular or transvenous systems. Longer term extraction data collection is ongoing through the EV ICD Pivotal study and through the EV ICD post-approval study and will continue to provide additional insights.Lead removed 24 months post-implant.