bluuebunny/crossref_metadata_2025_split huggingface dataset:
Causes and characteristics of sudden cardiac death in octogenarians/nonagenarians
Authors: Perkiomaki J , Puolitaival E , Vahatalo J , Holmstrom L , Haukilahti M A E , Pakanen L , Ukkola O H , Junttila M J , Huikuri H V 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): the Finnish Foundation for Cardiovascular Research
the Sigrid Jusélius Foundation

Introduction
The risk for sudden cardiac death (SCD) increases with ageing.

Methods
We evaluated causes and characteristics of unexpected SCD in SCD victims aged ≥ 80 years in a consecutive series of 5,869 SCD victims who underwent medico-legal autopsy.

Results
Among SCD victims ≥ 80 years, 91.0% of SCDs were due to ischemic heart disease (IHD) determined in autopsy and 9.0% due to non-ischemic heart disease (NIHD), whereas among those &lt; 80 years, only 72.6% of SCDs were due to IHD and 27.4% due to NIHD (P&lt;.001). Severe fibrosis in myocardium was more common whereas heart weight and liver weight, body mass index and abdominal fat thickness, were lower among SCD victims aged ≥ 80 years than among victims aged &lt; 80 years. In those with IHD as etiology of SCD, at least 75% stenosis in one or more major coronary vessels was more common in SCD victims aged ≥ 80 years than among victims aged &lt; 80 years (P=.001). Dying in sauna was more common among those ≥ 80 years than among those &lt; 80 years (5.5% vs. 2.6%, P&lt;.001).

Conclusion
In victims of unexpected SCD aged ≥ 80 years, the autopsy-based etiology of SCD was more commonly IHD than in those aged &lt; 80 years. In SCD victims aged ≥ 80 years, severe fibrosis in myocardium, representing arrhythmic substrate, was more common than in the younger ones.
Effect of infarct size on the risk of ventricular arrhythmias in patients with chronic total coronary occlusion
Authors: Hindi-Assaf A , Van Der Graaf M , Van Boven N , Van Ettinger M J B , Hoogendijk M , Diletti R , Szili-Torok T , Theuns D A M J , Yap S C 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The presence of an untreated chronic total coronary occlusion (CTO) is associated with a higher risk of ventricular arrhythmias (VAs). This increased risk may be modulated by the presence of existing scar. We hypothesize that a larger scar size is associated with a higher risk of VA.

Objectives
To evaluate whether infarct size is associated with VA in patients with an implantable cardioverter-defibrillator (ICD) and an untreated CTO.

Methods
In this retrospective study we included patients with an untreated CTO that received an ICD between 2005 and 2014. Infarct size was estimated using the Selvester QRS score on a baseline 12-lead ECG. The primary endpoint was any appropriate ICD therapy.

Results
Our study population comprised 148 patients (mean age at implantation 64 ± 10 years, 87% men) with an ICD and an untreated CTO. The median infarct size at baseline was 18% (IQR, 9-27%). Patients with a larger scar size (≥18%) more often had a CTO location in the LAD, higher proportion of LVEF &lt;35%, and less hypertension and hypercholesterolemia compared to patients with a smaller infarct size (&lt;18%). During a median follow-up of 35 months (interquartile range [IQR], 8-60 months), 42 patients (28%) received appropriate ICD therapy. The cumulative 5-year event rate was higher in the patients with a large infarct size (≥18%) in comparison to those with a smaller infarct size (&lt;18%) (36% versus 19%, logrank P = 0.038, Figure). Multivariable Cox regression analysis demonstrated that a larger infarct size (≥18%) and a secondary prevention indication were independent factors associated with appropriate ICD therapy. The adjusted hazard ratio of large infarct size (≥18%) for appropriate ICD therapy was 2.34 (95% CI 1.20-4.58, p=0.01).

Conclusion
In ICD recipients with an untreated CTO, a larger scar size is an independent factor associated with an increased risk of VA.
Recurrences of ventricular tachycardia after stereotactic arrhythmia radioablation arise outside the treated volume: analysis of the Swiss cohort
Authors: Herrera Siklody C , Schiappacasse L , Jumeau R , Reichlin T , Saguner A , Andratschke N , Elicin O , Kovacs B , Mayinger M , Huber A , Le Bloa M , Teres Castillo C , Domenichini G , Bourhis J , Pruvot E 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – EU funding. Main funding source(s): The project is part of the STOPSTORM.eu consortium and has partially received funding from the European Union’s horizon 2020 research and innovation program

Background
Stereotactic arrhythmia radioablation (STAR) has been recently introduced for the management of ventricular tachycardia (VT) refractory to antiarrhythmic drugs and catheter ablation (CA). VT recurrences have been reported after STAR but the mechanisms remain largely unknown.

Purpose
We analyzed recurrences in the Swiss Cohort after STAR for refractory VT in order to assess their location related to the irradiated volume.

Methods
From 09.2017 to 01.2020, 20 patients (68±8y, LVEF 37±15%) suffering from refractory VT were enrolled. The underlying cardiopathy was ischemic in 6, inflammatory in 4, neoplastic in 1 and idiopathic in 9 patients. Sixteen out of 20 patients had a history of at least 1 electrical storm. Before STAR, an invasive electro-anatomical mapping (Carto3) of the VT substrate was performed. A mean dose of 23±2Gy was delivered to the planning target volume (PTV).

Results
The median ablation volume was 26 ml (range 14-115) and involved the interventricular septum (IVS) in 75% of patients. During the first 6 months after STAR, VT burden decreased by 92% (median value, from 108 to 10 VT/semester, p&lt;0.005). After a median follow-up of 25 months, 12/20 (60%) developed a recurrence with 14 sustained VTs and underwent a redo CA. VT recurrence was located in proximity of the treated arrhythmogenic substrate in 9 cases, occurred remote from the PTV in 3 cases and involved a larger substrate over ≥3 LV segments in 2 cases. No recurrences occurred inside the PTV. The estimated dose delivered at sites of VT recurrence was very heterogeneous, ranging from 0.11 to 28.37 Gy, and less than 15 Gy in 12/14 cases. Voltage measurements showed a significant decrease in both bipolar and unipolar signal amplitude.

Conclusion
STAR is a precious new tool available for the treatment of therapy-refractory VT, allowing for a significant reduction of VT burden. VT recurrences are common during follow-up, but no recurrences were observed inside the PTV. Local efficacy was supported by a significant decrease in both bipolar and unipolar signal amplitude.
Incidence of ventricular tachyarrhythmias and clinical outcomes in primary prophylactic ICD patients in relation to localization of myocardial infarction
Authors: Kleemann T , Kouraki K , Strauss M , Mohammad O , Wenz A , Zahn R 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
According to current guidelines, primary prophylactic ICD implantation is indicated with a class IA recommendation in patients with severely reduced EF &lt; 35% and ischaemic heart disease. However, it is unclear whether there are differences in patient outcomes related to the localization of myocardial infarction. Aim of the study was to compare the incidence of ventricular tachyarrhythmias and clinical outcomes in primary prophylactic ICD-patients with ischaemic heart disease in relation to the localization of myocardial infarction.

Methods
A total of 448 consecutive ICD patients from a prospective single-centre ICD-registry who underwent primary prophylactic ICD implantation due to ischaemic cardiomyopathy between 1996 and 2021 were analyzed. Patients with previous anterior wall myocardial infarction (AWMI, n = 293) were compared to those with posterior wall myocardial infarction (PWMI, n = 155). Patients with both AWMI and PWMI were excluded. The median follow-up time was 6 years in both groups.

Results
Patients with AMWI were younger, more often female, and less often received cardiac synchronization therapy (Table 1). Patients with previous PWMI more often had ICD therapy during follow-up (Figure 1) due to the higher incidence of ventricular tachycardias (Table 1). The all-cause mortality rate was similar between both groups.

Conclusion
Primary prophylactic ICD patients with previous PWMI have a 10% higher incidence of ventricular tachycardias after 6-year follow-up than ICD patients with previous AMWI. This might be explained by the proximity of the inferior infarction to the mitral isthmus and should be considered when ablating VTs in patients with PWMI.
New imaging techniques in ventricular tachycardia ablation: integration of myocardial thickness analysis software in computed tomography with omnipolar mapping
Authors: Cabrera Borrego E , Sanchez Millan P , Constan De La Revilla E , Tercedor Sanchez L , Alvarez Lopez M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background/Introduction
Magnetic resonance imaging (MRI) is very useful for planning the ablation of ventricular tachycardias (VT) related to scar, since it allows identification of anatomy, scar dense/border zone (DZ/BZ) and conduction channels (CC). However, access to this test is limited in many centres and, in addition, artefacts generated by pacing/defibrillation devices (ICDs) can often make it uninterpretable. Multidetector cardiac computed tomography (MDCT) offers the advantages of greater accessibility, better anatomical characterisation and less device artefacts, although there is little experience of its use.

Purpose
The objective is to evaluate the effectiveness of integrating myocardial thickness analysis software with MDCT and omnipolar electroanatomical mapping for VT ablation procedures in patients with cardiomyopathy.

Methods
Single-centre, descriptive study of a serie of patients, ICD carriers, that underwent VT ablation:
- Patient 1- 72-year-old male with ischaemic heart disease.
- Patient 2- 46-year-old male with left arrhythmogenic cardiomyopathy.
- Patient 3- 60-year-old male with biventricular arrhythmogenic cardiomyopathy.
- Patient 4- 28-year-old female with right arrhythmogenic cardiomyopathy.
MDCT was performed on all patients and the images were post-processed using myocardial thickness analysis software. A 3D colour map was created with identification of the DZ, BZ and CC. This map was fused with the electroanatomical map created during the electrophysiological study with omnipolar technology.

Results
In all cases there was a high anatomical correlation between DZ, BZ and CC detected on postprocessed MDCT and the area of pathological voltage and late electrograms of the omnipolar map. In patient-1, the CC detected on CT coincides with the diastolic corridor of clinical VT (image 1A). In patient 2, CT analysis identified the direct relationship of the circumflex artery with the superior region of the DZ (image 1B). In patients 3 and 4, the CT scan identified the relationship of the DZ/BZ in the right ventricular outflow tract with the coronary arteries and phrenic nerve (image 1 C and D).

Conclusions
The computed tomography myocardial thickness analysis software is positioned as an alternative to MRI in VT ablation, as it localises critical anatomical structures and identifies the scar dense/border zone and conduction channels accurately.
Omnipolar technology in ventricular tachycardia ablation: activation and substrate mapping with late activation isochrone analysis under extrastimulus protocol
Authors: Cabrera Borrego E , Sancez Millan P , Constan De La Revilla E , Tercedor Sanchez L , Alvarez Lopez M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
The cornerstone of the ablation of eschar-related ventricular tachycardias (VT) is the circumscription of the scar dense zone (DZ)/border zone (BZ) and the identification of regions of slow decremental conduction. The anisotropy of the BZ generates depolarisation waves with rapid changes in their direction that may not be detected by bipolar electrodes, as their identification capacity is orientation-dependent. Omnipolar technology detects the direction and velocity of the wavefront regardless of its orientation.

Purpose
Describe the effectiveness of the use of omnipolar technology for the development of electroanatomical and activation maps during the study of VT related to scar.

Methods
Single-centre, observational, descriptive study of a serie of patients:
- Patient 1- 72-year-old male with ischaemic heart disease.
- Patient 2- 46-year-old male with left arrhythmogenic cardiomyopathy.
- Patient 3- 60-year-old male with biventricular arrhythmogenic cardiomyopathy.
- Patient 4- 28-year-old female with right arrhythmogenic cardiomyopathy.
- Patient 5- 42-year-old male with non-ischemic dilated cardiomyopathy.
- Patient 6 - 73-year-old male with arrhythmogenic right cardiomyopathy.
Omnipolar technology was used for the creation, under sensed extrastimuli in right ventricular apex protocol, of a voltage map, isochrone late activation map (ILAM), slow decremental conduction (SDC) analysis and, in case of VT induction, activation map with real-time visualisation of conduction vectors ("Strategic-multielectrode-positioning" / StaMP-mapping).

Results
In patients 1, 2 and 3 ILAM was performed identifying SDC regions. After induction of VT, StaMP-mapping was performed in these regions with identification of the diastolic corridor (image 1A, 1B, 1C). The corridor was eliminated and, subsequently, arrhythmogenic substrate ablation of late potentials in DZ/BZ was performed.
In patients 4, 5 and 6 an identical protocol was performed, but VT induction was not achieved, so substrate ablation strategy was performed (image 1D, 1E, 1F).
Patient 6 has had a recurrence of sustained VT.

Conclusions
Omnipolar technology, associated with the extrastimulus protocol, allows a more accurate study of scar-related VT, through the identification of SDC regions. These locations are current targets for substrate ablation and, in many cases, the origin of the critical isthmus.
Association between left ventricular wall-thickness by CT and endocardial voltage potentials in patients with ischemic cardiomyopathy
Authors: Gomes D , Cunha G , Freitas P , Guerreiro S , Abecasis J , Rodrigues G , Matos D , Carmo J , Galvao Santos P , Moscoso Costa F , Carmo P , Belo Morgado F , Cavaco D , M Ferreira A , Adragao P 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Although cardiac magnetic resonance (CMR) is the gold standard for planning ventricular tachycardia (VT) ablation, its accuracy is hindered in patients with implanted cardiac defibrillators (ICD) and resynchronization therapy (CRT). Cardiac computed tomography (CT) has emerged as an alternative for ablation planning in these patients. This pilot study aimed to evaluate the relationship between wall thickness (WT) on CT and voltage of electrical potentials on endocardial electroanatomic mapping (EAM) in patients with ischemic cardiomyopathy.

Methods
Single centre retrospective study enrolling consecutive patients with ischemic cardiomyopathy referred for endocardial VT ablation that underwent cardiac CT for procedure planning since 2021. Patients were excluded if EAM had &lt; 1000 data points. ADAS 3D® software was used to analyse CT images, automatically segmenting the left ventricle (LV) into the 17 American Heart Association segments and calculating end-diastolic WT for each one. Four standardized views (anterior-posterior, posterior-anterior, superior, and inferior) of the segmented LV on ADAS 3D® were used to aid in manual segmentation of the EAM. The endocardial voltage maps were created using CARTO3® software (Figure 1). For each patient, EAM was interpreted to create 2 different bulls’ eye maps, according to the presence or absence of bipolar potentials &lt; 0.5 (dense scar) or &lt; 1.5mV (low voltage). Only segments with &gt;20% extension of low bipolar voltage were considered as altered.

Results
We included a cohort of 8 patients (mean age 67±12 years, 87.5% male, median LVEF of 32% [IQR 25-49]). All but one patient had implanted cardiac device (6 ICD, 1 CRT-D). Cardiac CT was performed 1 day (IQR 0-2) before the ablation. Overall, 136 segments were analysed, 8 of which did not have voltage information. Of the remaining 128, 51 (39.8%) had dense scar and 57 (41.9%) had low voltage. There was a good correlation between mean WT and the presence or absence of both dense scar (area under de curve (AUC) 0.799, p&lt;0.001) and low voltage (AUC 0.838, p&lt;0.001) in each LV segment.

Conclusion
WT measured by CT appears to have a strong correlation with dense scar and low voltage in EAM in patients with ischemic cardiomyopathy undergoing VT ablation. This technique may be useful to plan interventions in patients in whom CMR is not feasible.
Characteristics and outcomes of catheter ablation of ventricular arrhythmias originating from the left ventricular summit
Authors: Sanchez Millan P J , Sanchez Moreno J M , Constan De La Revilla E , Cabrera Borrego E , Tercedor Sanchez L , Alvarez Lopez M 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Catheter ablation (CA) of the left ventricular summit (LVS) arrhythmias is a challenging procedure due to the inherent complexity anatomy of that region. Different anatomical approaches are usually performed for mapping this area including deep intramural location. The objective of this study is to investigate the procedural outcomes of ablation of LVS arrhythmias.

Methods
Retrospective analysis of 32 consecutive patients (mean age 58±12 years old) who underwent CA of LVS arrhythmia in a single center. Baseline characteristics, procedural parameters and clinical outcomes were analyzed.

Results
All LVS arrhythmias had inferior and vertical axis (positive inferior leads with negative aVR and aVL leads). LBBB pattern was found in 25/32 (78%) and RBBB pattern in 7/32 (22%). 14/32 (44%) patients presented a "w" morphology in DI lead. 18/32 (56%) cases showed abrupt V3 transition. 13/32 (41%) patients had a previous failed ablation. Direct mapping of the intramural septum, through the septal perforator veins, was performed using a wire or a multipolar 2Fr catheter in 19 patients (59%). The earliest activation area was recorded in LCC-RCC in 13 patients (41%) followed by a septal perforator vein in 9 patients (28%). Most patients required multisite sequential ablation for achieving success (20 patients, 62%). Acute arrhythmia suppression was achieved in 22 patients (69%) and only 1 patient presented a complication (pericardial tamponade). Late success was noted in 3 patients (9%). During a median follow up of 9,79±8,6 months, 23 patients (72%) maintained a sustained acute success (80% reduction of PVC burden at least) None of the 9 patients without sustained acute success needed to repeat ablation.

Conclusions
Ablation of LVS arrhythmias is a challenging procedure with frequent previous ablation attempts. The earliest activation area is commonly found between LCC-RCC junction and in the intramural septum. Multisite non-conventional anatomical mapping and ablation steps are required to obtain a sustained success.
A method to identify which patients will have VT substrate ablation targets prior to ablation procedure
Authors: Burg M , Anderson R D , Gonna H , Al-Shaheen A , Niri A , Shapira E , Ben-Dor A , Hayam G , Baron T , Masse S , Nanthakumar K 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Dr Nanthakumar is a recipient of the Mid-career Investigator Award from the Heart & Stroke Foundation of Ontario

Background
Recent trials in ventricular tachycardia (VT) ablation suggest that early ablation could reduce VT burden. A method to predict which patients will have substrate ablation targets based on non-invasive testing prior to the procedure does not exist and could be of value in selecting ideal patients for early VT substrate ablation. Decrement-evoked potential (DeEP) mapping is used to identify VT substrate ablation targets.1 A method for predicting which patients would have DeEP targets on a pre-ablation 12-lead ECG has not yet been developed.

Objective
To develop a metric to predict the presence of physiological substrate VT ablation targets from the 12-lead ECG.

Method
22 electrophysiology (EP) lab VT cases that had undergone DeEP mapping were extracted from the CARTO® 3 system and were analysed retrospectively. For each case, DeEP was calculated by subtracting last component of the nearfield evoked response in the pacing train (S1) from the latest component of the nearfield evoked decremented response of the extra stimulus (S2). By inference, 12-lead ECG prediction was calculated by subtracting the width of the 12-lead surface ECG envelope of S1 from the width of the 12-lead ECG envelope of S2. Cases were divided into three categories:
- Cases displaying intracardiac DeEP between 0-10ms – no ablation targets
- Cases displaying intracardiac DeEP between 10-50ms – DeEP positive
- Cases displaying intracardiac DeEP &gt;50ms – prominent DeEP present

Results
Out of the 22 cases, 8 were characterised as no ablation targets, 12 as DeEP positive, and 2 as prominent DeEP present. The 12-lead surface ECG measurement means were 3.5±4.6ms for the no ablation target group, 23.2±9.1ms for positive DeEP group, and 80.9±8.1ms for prominent DeEP group. The surface ECG decrement was significantly different P&lt;0.0001 between the three groups. Consequently, we propose that ECG QRS widening of envelope width of 20ms or more may indicate the presence of DeEP targets during invasive mapping.

Conclusion
It may be possible to detect which patients will have substrate ablation targets based on 12-lead ECG, prior to the VT ablation procedure. Additionally, this prediction rule, based on its association with arrhythmogenic potentials, may be able to predict which ambulatory patients who have not had manifest VT, may be prone to develop VT thus help identify early VT ablation candidates. This concept should be validated in larger data sets and is ideal for training and testing using surface ECG envelopes with artificial intelligence algorithms.