bluuebunny/crossref_metadata_2025_split huggingface dataset:
More than half of all sudden cardiac deaths occur in persons without a history of cardiovascular disease: A study of 54,028 deaths in Denmark
Authors: Lynge T , Skjelbred T , Svane J , Garcia R , Winkel BG , Tfelt-Hansen J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Public hospital(s). Main funding source(s): Copenhagen University Hospital, Rigshospitalet

Background
Sudden cardiac death (SCD) is a major public health problem accounting for a large proportion of global mortality. Previous studies suggest that SCD often occurs in the general population in persons not previously diagnosed with cardiovascular disease. It is evidently challenging to identify high-risk persons in an overwhelmingly large population of mainly healthy individuals and studies are needed to further characterize these SCD cases.

Purpose
To estimate SCD burden in patients not previously diagnosed with cardiovascular disease and to characterize these SCD cases.

Methods
All deaths in Denmark (population of 5.5 million) in 2010 were manually reviewed case-by-case. Autopsy reports, death certificates, and information from nationwide health registries were systematically examined to identify all SCD in 2010. The Danish National Patient Register contains information on all in- and outpatient activities at Danish hospitals and emergency departments and was used to identify all SCD cases with a previous cardiovascular diagnosis.

Results
There were 54,028 deaths in Denmark in 2010, of which 6,867 (13%) were categorized as SCD. Overall incidence rate of SCD was 124 (95%-CI: 121-127) per 100,000 person-years. Of all SCD, 59% were not diagnosed with cardiovascular disease prior to death. SCD incidence in persons with and without a history of cardiovascular disease was 790 (95%-CI: 762-820) and 78 (95%-CI: 75-80) per 100,000 person-years, respectively. This corresponds to an incidence rate ratio of 10 (95%-CI: 10-11). SCD cases with no previously diagnosed cardiovascular diseases were younger (median age 75 vs. 80 years, p&lt;0.001), more often female (45 vs. 42%, p=0.019), and on average had a lower household income (p=0.002) (Table 1). SCD cases not diagnosed with cardiovascular disease prior to death in general had fewer comorbidities, except for psychiatric diseases, which were more common in the undiagnosed group (Table 1).

Conclusion
In this large and nationwide study of all SCD in Denmark in 2010, more than half of all SCD occurred in persons without a history of cardiovascular disease. This suggests that SCD is often first manifestation of disease. We currently do not have accurate tools for SCD risk stratification in the general population and future research is needed to identify modifiable and easily measured risk factors of SCD in the general population.
The peri-infarct gray zone of myocardial fibrosis is a better predictor of ventricular arrhythmias than dense core fibrosis in patients with previous myocardial infarction
Authors: Lopes P , Cunha G , Freitas P , Rocha B , Matos D , Rodrigues G , Carmo J , Carvalho MS , Galvao Santos P , Costa FM , Carmo P , Cavaco D , Morgado F , Ferreira A , Adragao P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Current sudden cardiac death (SCD) risk stratification relies heavily on left ventricular ejection fraction (LVEF), but markers to refine risk assessment are needed. Dense core fibrosis (DCF) and peri-infarct "gray zone" of myocardial fibrosis (GZF) on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) have been proposed as potential arrhythmogenic substrates. The aim of our study was to determine whether DCF and GZF could predict the occurrence of ventricular arrhythmias in patients with previous myocardial infarction.

Methods
We performed a single centre retrospective study enrolling consecutive patients with previous myocardial infarction undergoing CMR before implantable cardioverter-defibrillator (ICD) implantation. Areas of LGE were subdivided into "core" DCF and "peri-infarct" GZF zones based on signal intensity (&gt;5 SD, and 2-5 SD above the mean of reference myocardium, respectively).
The primary endpoint was a composite of sudden arrhythmic death, appropriate ICD shock, ventricular fibrillation (VF), or sustained ventricular tachycardia (VT) as detected by the device.

Results
A total of 88 patients (median age 61 years [IQR 54-73], 84% male, median LVEF 30% [IQR 23-36%], 14% secondary prevention) were included. During a median follow-up of 23 months [IQR 9-38], 13 patients reached the primary endpoint (10 appropriate ICD shock, 2 sustained VT or VF, and 1 sudden arrhythmic death). Patients who attained the primary endpoint had similar DCF (30.4g ± 14.7 vs. 28.0g ± 15.3; P = 0.601) but a greater amount of GZF (18.1g ± 9.6 vs. 11.9g ± 6.7; P = 0.005). On univariate analysis, GZF was associated with the composite endpoint (HR: 1.09 per gram; 95%CI: 1.02-1.15; P = 0.006), whereas DCF was not (HR: 1.01 per gram; 95%CI: 0.98-1.05; P = 0.571). After adjustment for LVEF, GZF remained independently associated with the primary endpoint (adjusted HR: 1.06 per gram; 95% CI: 1.01-1.12; P = 0.035). Decision tree analysis identified 11.9g of GZF as the best cut-off to predict life-threatening arrhythmic events. The primary endpoint occurred in 11 out of the 35 patients (31.4%) with GZF ≥11.9g, but in only 2 of the 53 patients (3.8%) with GZF &lt;11.9g – Figure.

Conclusions
The extent of peri-infarct GZF seems to be a better predictor of ventricular arrhythmias than DCF. This parameter may be useful to identify a subgroup of patients with previous myocardial infarction at increased risk of life-threatening arrhythmic events.
SAECG - advances in Brugada stratification
Authors: Brito J , Silverio Antonio P , Silva P , Couto Pereira S , Valente Silva B , Cunha N , Nunes-Ferreira A , Lima Da Silva G , Neves I , Cortez-Dias N , J Pinto F , Sousa J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Brugada syndrome (BrS) is a relevant cause of sudden cardiac death (SCD) in young adults. Several risk factors have been identified, but clinical decision making remains extremely challenging, particularly in asymptomatic patients.

Purpose
To explore the usefulness of the non-invasive assessment of late potentials (LPs) based signal-averaged ECG (SAECG) for risk stratification in BrS.

Methods
Prospective single-center study of patients with BrS included from 2003 to 2021. LPs were evaluated by SA-ECG with determination of the total filtered QRS duration (fQRS), root mean square voltage of the 40ms terminal portion of the QRS (RMS40) and duration of the low amplitude electric potential component of the terminal portion of the QRS (LAS40) in conventional and modified right precordial leads.
The primary endpoint was the occurrence of malignant arrhythmic events (MAEs), defined as a composite of SCD or appropriate shocks. Uni- and multivariate Cox regression survival analyses were used to identify significant prognostic predictors considering the clinical, genetic, and electrocardiographic characteristics as well as the tercile distribution of the SAECG parameters. A risk score was computed incorporating the significant LPs variables and its usefulness for prognostic stratification was explored using Kaplan Meier survival analysis.

Results
Our cohort consisted of 117 patients (mean age: 47±13 years, 33% male), including 75 (65%) with type 1 spontaneous pattern and 92 (79%) asymptomatic individuals. Symptoms at presentation included syncope in 16 pts (14%) and polymorphic VT/cardiac arrest in 4 (3.4%).
During a median follow-up of 4.1±0.3 years, 8 pts (6.8%) suffered MAEs: 3 (2.6%) with SCD and 5 (4.3%) with appropriate shocks.
The risk of events differed in relation to the several SAECG parameters (Table 1), increasing linearly with the fQRS duration determined either in the conventional (HR 1.03, 95% CI 1.01-1.06, p=0.008) or modified leads (HR: 1.03, 95% CI 1.01- 1.05, p=0.003). The SAECG score incorporated as risk markers a fQRS ≥113ms and a RMS40 &lt;13 μV. Patients with both risk markers presented a 7-fold increased risk (HR 7.17, 95% CI 1.29-40, p = 0.025), independently of the baseline symptomatic status and ECG pattern.

Conclusion
This study shows that the non-invasive assessment of LPs based on SAECG is useful for prognostic stratification of BrS. It was possible to identify a subset of patients presenting a high risk of events who may deserve individualized preventive strategies.
PVC ablation without fluoroscopy
Authors: Pena Mellado J , Sanchez Millan P , Gutierrez Ballesteros G , Tercedor L , Alvarez Lopez M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Premature ventricular complex(PVC) catheter ablation is required in a wide spectrum of the population.Ionizing radiation exposure in this procedure carries health risks, especially in young patients.

Purpose
In this prospective observational study we describe our experience in PVC ablation without fluoroscopy

Methods
26 patients were included, submitted to PVC ablation without fluoroscopy between October 2018 and November 2021, in our center. Baseline characteristics of the population, acute success and complications derived from the procedure were evaluated, as well as recurrence rate during follow-up.

Results
Mean age was 45.5± 16.3 years old, with a 46.2% of men. Most often cause of ablation were palpitations(73.1%),followed by reduced LVEF(19.2%). Mean LVEF by transtoracic echocardiography was 52.4 ± 11%. 38.5% had a cardiopathy, among them the most common was tachycardiomyopathy(49.9%).Mean PVC burden pre-ablation was 23.6±11.5%. 65% of patients were taking beta blockers. The most frequent PVC origin was the right ventricle outflow tract(RVOT), with a 65.4% prevalence, followed by the left ventricle outflow tract(LVOT) with 15.4%.We used a 3D electroanatomical navigation system in all cases,while intracardiac echocardiography was used in 88.5% and a contact force catheter for mapping(57.7%) and ablation(92.3%).The mean maximum radiofrequency power applied was 34 ±5.8W, with a median time of 240 seconds. Median number of applications was 6 and mean total time of procedure was 210 ±67,5 minutes. 28ms median best prematurity.
Suppression of PVC was achieved in 88.5%. There was only two complications(7.6%): pericardial effusion without the need for pericardiocentesis and right brunch block.Median follow-up of 3 months, with 23% of recurrences. Most of patients(57.7%) did not require antiarrhythmics drugs during it.

Conclusions
Zero fluoroscopy PVC ablation is a safe procedure with no major complications and good rates of success and recurrence in our experience
Sinus rhythm endocardial mapping for channels identification in ischemic ventricular tachycardia using a modified electrophysiological triad
Authors: Adragao P , Nascimento Matos D , Galvao Santos P , Costa FM , Rodrigues G , Carmo J , Salome Carvalho M , Carmo P , Cavaco D , Morgado F , Mendes M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
In a previous study it was demonstrated that an electrophysiological triad was able to identify critical isthmus in atrial flutter (AFL) patients. This triad is based in the Carto® electroanatomical mapping (EAM) version 7, which displays a histogram of the local activation times (LAT) of the tachycardia cycle length (TCL), in addition to the activation and voltage maps.

Purpose
This study aimed to prospectively assess the ability of a modified electrophysiological triad to identify and localize the ventricular tachycardia’s (VT) channels and entrance zones during sinus rhythm mapping.

Methods
Prospective analysis of a unicentric registry of individuals who underwent ischemic VT ablation with Carto® EAM, all in sinus rhythm. All patients with non-ischemic etiology, lack of high-density EAM or lack of mapping in any of the left ventricle walls or structures were excluded. Areas of late potentials and possible channels of re-entry were compared to a modified electrophysiological triad constituted by: areas of low-voltage (&lt;0.5mV), a site of deep histogram valley (LAT-Valley) with less than 20% density points relative to the highest density zone and a prolonged LAT-Valley duration that included 10% or more of the total activation time mapped. We also assessed the relationship between the pre-valley bar (the LAT histogram bar immediately before the prolonged LAT-Valley) and the channel entrances.

Results
A total of 14 patients (14 men, median age 70 IQR 64-78 years) were included. All patients presented with ischemic VT and 86% had a previous inferior myocardial infarction. The median number of collected points were 1733 (IQR 1363─2729). All sinus rhythm maps presented with at least 1 LAT-Valley in the analysed histograms. All arrhythmias were effectively treated after undergoing radiofrequency in the LAT-Valley location, either by blocking the channel entrances or scar homogenization ablation strategy. Also, the pre-valley bar in the histogram marked all the channel entrances in the scar borders. No patient had relapse after a clinical follow up of over 6 months.

Conclusion
In a prospective analysis, a modified electrophysiological triad was able to identify the scar channels in sinus rhythm in all patients. The pre-valley bar in the histogram disclosed the channel entrances. Further studies are needed to assess the usefulness of this algorithm to simplify catheter ablation and improve clinical outcomes.
Non-ischemic cardiomyopathy: what predicts survival and ICD shocks after ventricular tachycardia ablation?
Authors: Oliveira C , Silverio Antonio P , Couto Pereira S , Valente Silva B , Brito J , Alves Da Silva P , Martins AM , Garcia B , Azaredo Raposo M , Nunes Ferreira A , Lima Da Silva G , Carpinteiro L , Cortez-Dias N , J Pinto F , Sousa J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Patients (pts) with non-ischemic cardiomyopathy (NICM) present an increased morbidity and mortality from sustained monomorphic ventricular tachycardia (VT). Implantable cardiac defibrillators effectively terminate VT, but ablation is usually required to prevent recurrences and appropriate shocks. Although several risk factors have been pointed out, clear prognostic predictors need to be established and addressed.

Purpose
To evaluate risk factors associated with all-cause mortality and ICD shocks in NICM pts submitted to VT ablation.

Methods
Prospective, observational, single-centre study of pts with NICM submitted to VT ablation using high density mapping tools.The primary outcome was all-cause death or VT recurrence terminated with appropriate ICD shock during long-term follow up. Kaplan-Meier analysis was used to estimate the long-term event-free survival. Uni and multivariate Cox regression analyses were used to determine relevant prognostic predictors.

Results
A total of 27 consecutive pts with NICM were referred for a first-ever VT ablation procedure between June 2015 and June 2021 (males: 93%; mean age: 61±12 years). The mean left ventricular ejection fraction (LVEF) was 35±12% and 70% of pts had NYHA class I or II.
During a mean follow-up of 29 ± 19 months, VT recurrences requiring ICD shocks occurred in 25.9% of pts. VT ablation success and the risk of ICD shocks were not associated with any of the clinical characteristics. Long-term all-cause mortality was 37%. In univariate analysis, LVEF &lt;30%, NT-proBNP, NYHA classification III-IV, chronic kidney disease (CKD), ICD for secondary prevention and prior VT ablation (p=0.08) were associated with reduced survival. On multivariate analysis, CKD was identified as the strongest independent survival predictor (HR 6.9; CI95%: 1.5-23-2, p=0.010)

Conclusions
In pts with NIDM, VT ablation may be successful even in pts with advanced heart disease. However, long-term survival will depend mostly on the stage of disease progression and is strongly associated with the clinical markers of end-stage heart failure. Therefore, a timely referral is crucial to derive the best clinical benefit from VT ablation in this population.
Initial experience of left bundle branch area pacing using stylet-driven pacing leads: a multicenter study
Authors: De Pooter J , Ozpak E , Calle S , Peytchev P , Heggermont W , Marchandise S , Provenier F , Francois BART , Anne W , Barbaud C , Gillis K , Vanheuverswyn F , Tung R , Wauters A , Le Olain De Waroux JB 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left bundle branch area pacing (LBBAP) has been performed exclusively using lumen-less pacing leads (LLL) with fixed helix design. This study is the first to explore in a multicenter population the safety and feasibility of LBBAP using stylet-driven leads (SDL) with extendable helix design.

Methods
This study prospectively enrolled all consecutive patients who underwent LBBAP for anti-bradycardia pacing or heart failure indications at 8 Belgian hospitals. LBBAP was attempted either using SDL or LLL delivered through dedicated delivery sheaths. Implant success, complications, procedural and pacing characteristics were recorded at implant and follow-up.

Results
The study enrolled 412 patients (mean age 74 ± 38 years, 44% female). LBBAP with SDL and LLL was successful in 334/353 (94%) and 52/59 (88%) respectively (p=0.058). Implant success for LBBAP using SDL varied from 93 to 100% among centers. Mean paced QRS duration and stimulus to left ventricular activation time were comparable for SDL and LLL (126 ± 21ms versus 125 ± 22ms, p=0.861 and 74 ± 17 and 75 ± 21ms, p=0.756). SDL LBBAP resulted in low pacing thresholds (0.6 ± 0.4V at 0.4ms), which remained stable at 1, 6 and 12 months of follow-up. Lead revisions for SDL LBBAP occurred in 5(1.4%) patients: 2 dislodgements at day 1, 1 late septal perforation at week 3, 1 Twiddler’s syndrome at 5 months, 1 lead fracture at 6 months.

Conclusion
This multicenter study confirms the safety and feasibility of LBBAP using SDL, which is characterized by high implant success, low complication rate and low and stable pacing thresholds.
Conduction system pacing in paediatric patients: a single centre experience
Authors: Zizek D , Topalovic M , Stublar J , Mrak M , Jan M , Weiss M 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Paediatric patients with conduction abnormalities are generally exposed to life-long dyssynchronous pacing from a very early age. Thus, preservation of cardiac function during chronic ventricular pacing is important. Conduction system pacing (CSP) with His bundle pacing (HBP) or left bundle branch pacing (LBBP) is an alternative method to standard right ventricular (RV) pacing that may preserve physiological ventricular activation and avoid potential pacing-induced cardiomyopathy (1). However, data on feasibility and safety of various CSP approaches in paediatric patients with or without congenital heart disease (CHD) is scarce and mainly relies on case studies (2-4).

Purpose
To assess feasibility and outcomes of different CSP techniques in paediatric patients.

Methods
Consecutive paediatric patients in whom CSP was attempted in our centre between November 2019 and December 2021 were analysed. Acute implant success rate, complications, fluoroscopy times, and CSP pacing parameters during follow-up were assessed.
To reduce radiation exposure, minimal fluoroscopy technique with three-dimensional (3D) electro-anatomical mapping (EAM) was also used in some cases. Geometry of right atrium and RV, along with mapping of His signal for HBP and potential LBBP sites in the RV septum were created using a decapolar catheter from the right femoral vein. Once relevant anatomy was obtained, HBP or LBBP was attempted using commercially available CSP tools. The pacing lead tip was visualised using the 3D EAM system. Transient fluoroscopy was used only for perpendicular placement of the sheath to the RV septum during LBBP, sheath removal, lead loop assessment to allow linear growth, and atrial lead placement.

Results
Six patients (100% female, age 9.3 ± 3.9 years, weight 41.8 ± 22.9 kg, baseline QRS 111.5 ± 6.3ms, CHD 50%, previous device 33%) with congenital complete AV block received CSP. One patient received HBP and 5 LBBP. The procedure was acutely successful in all patients (100%), pacing thresholds were low (0.56 ± 0.18V at 0.5ms) and there were no perioperative complications. During mean follow-up of 11.8 ± 7.8 months pacing parameters remained stable. However, significant rise of the pacing threshold (&gt; 2.5V) was registered in the HBP patient, in whom lead revision was performed. Three-dimensional EAM was utilised in 3 patients (1 HBP, 2 LBBP). The use of minimal fluoroscopy technique with 3D EAM reduced fluoroscopy time (4.0, 3.2, 4.5 min vs. 9.5, 11.0, 8.0 min) without increasing procedural time (80, 70, 50 min vs. 110, 60, 75 min) compared to standard fluoroscopy technique.

Conclusion
Conduction system pacing is feasible and safe in paediatric patients with or without CHD. Additional utilisation of 3D EAM could reduce radiation exposure, without increasing procedural time. Future long-term studies should be considered to provide the ground for wider clinical adoption of CSP in paediatric population.