bluuebunny/crossref_metadata_2025_split huggingface dataset:
Participation of epicardial connection in transverse conduction across the crista terminalis in patients with upper and lower loop reentry atrial tachycardias
Authors: Ishihara T , Takasugi N , Wakasa S , Ichiryu H , Masuda Y , Naruse G , Watanabe T , Yamada Y , Kanamori H , Okura H 
Published: October 2024

Abstract

Background
The crista terminalis (CT) sometimes serves as a partial or complete conduction barrier, which is rate- and site-dependent. The basis, location and extent of the transverse conduction across the CT have been controversial. The pseudo-focal activation pattern indicates passive activation from the anatomically opposite chamber or structure. We previously reported cases of transverse CT conduction exhibiting a pseudo-focal activation pattern, indicating the CT conduction utilizing an epicardial connection (EC) in patients with upper loop reentry (ULR) atrial tachycardia (AT).

Purpose
This study aimed to investigate the prevalence and characteristics of transverse CT conduction using a high-resolution electroanatomical mapping system during CT-dependent AT and to compare between the ULR and lower loop reentry (LLR) ATs.

Methods
A total of 119 consecutive patients with macroreentrant AT were studied. The diagnosis of ULR/LLR AT was made based on endocardial activation mapping and entrainment pacing obtained from various sites around the superior/inferior vena cava. Transverse CT conduction utilizing an EC was defined as follows; (1) a centrifugal activation pattern with the earliest activation (EA) site &gt;5 mm away from the CT, (2) later activation observed between the EA and the CT, and (3) the EA site exhibiting a pseudo-focal activation pattern (multiple breakthroughs or a small r wave on unipolar electrogram).

Results
Eighteen (15.1%) of the 119 patients were diagnosed with CT-dependent AT (15 men; median age, 71.5 years; AT cycle length, 265 ms; left atrial diameter, 42.5 mm; left ventricular ejection fraction, 49%). The 18 patients were divided into 2 groups: 9 patients with ULR and 9 with LLR AT. There were no significant differences in clinical characteristics (sex, history of cardiac surgery and organic heat disease) between ULR and LLR groups. Transverse CT conduction utilizing EC was more frequently observed in the ULR group than in the LLR group [77.8% (7/9) vs 22.2% (2/9), P=0.05]. In all patients with transverse CT conduction utilizing EC, scars extended along the CT. AT cycle length was significantly longer in the ULR group than in the LLR group (295 vs 235 ms, p=0.001). All ATs were successfully eliminated by radiofrequency ablation at the breakthrough sites and/or along the CT in ULR patients or by cavotricuspid isthmus ablation in LLR patients.

Conclusions
Half (9/18) of the patients with CT-dependent AT exhibited transverse CT conduction with a pseudo-focal activation pattern, suggesting the existence of an EC between the sinus venosus and the right auricle. The high prevalence of the pseudo-focal pattern in patients with the ULR compared to those with the LLR may provide insights into mechanisms.Figure1Figure2
Collision mapping enables accurate localization of the slow pathway in atrioventricular nodal reentrant tachycardia
Authors: Seewoester T , Dilk P , Nedios S , Oebel S , Lindemann F , Deserio M , Feher M , Bollmann A , Bode K 
Published: October 2024

Abstract

Introduction
Atrioventricular Node Reentry Tachycardia (AVNRT) is commonly treated with catheter ablation, with high success and low complication rates. However a small risk of complete AV block still remains. Recent studies could show that using collision map is a feasible approach in mapping the slow pathway.
The aim of the current study is to show a reduction of the total ablation points needed to modify/ablate the slow pathway using the collision mapping compared to conventional 3D mapping guided slow pathway modulation/ablation and therefore minimize the risk of a complete heart block.

Methods
Patients diagnosed with AVNRT (n = 24) underwent collision mapping for slow pathway identification, compared to a historical cohort (n=76) using conventional mapping.
For collision mapping a dynamic visualization of atrial propagation during sinus rhythm was condcted. Two propagation fronts were observed to collide at the triangle of Koch, one propagation through the slow and one through the fast pathway. The designated collision zone was considered ideal for catheter ablation (Figure 1). The endpoint after ablation in both groups was non-inducibility of AVNRTs.

Results
After propensity score matching the collision mapping group needed significantly fewer ablation impulses (2 (IQR 1 - 5) vs. 6 (IQR 2,5 - 11,5) p = 0.002) and shorter ablation time (p &lt; 0.001) compared to the conventional group (Table 1). No significant differences were observed in procedure time (p = 0.209), fluoroscopy time (p = 0.296), or dose area product (p = 0.391).

Conclusion
Collision Mapping in AVNRT ablation showed a notable reduction in ablation points, suggesting enhanced procedural efficiency and safety.Figure 1Table1
Safety of electrophysiological study in atrioventricular block risk stratification in new-onset persistent left bundle brunch block following transcathether aortic valve implantation
Authors: Iraola Viana D , Sanchez-Gomez J M , Garcia Blas S , Jimenez Aguilella A , De Las Heras Pellicer L , Gabaldon Perez A , Martinez Brotons A , Bondanza Saavedra L , Dominguez Mafe E , Sanchis Fores J , Ferrero A 
Published: October 2024

Abstract

Background
A significant percentage of patients develops a persistent complete left bundle branch block (LBBB) following TAVI. Electrophysiological (EP) study could be useful to stratify the risk of atrioventricular block (AVB) in these patients, guiding the need of follow-up and the indication of definite pacemaker.

Purpose
The primary objective of the study was describing the incidence of bradyarrhythmic events in the 30-day follow-up of patients with new-onset LBBB: AV block with ECG long-term monitoring system (Nuubo) in patients with negative EP study, and ≥ 5 % of ventricular stimulation in patients with positive EP study and pacemaker implantation.

Methodology
Observational prospective study of consecutive patients without previous permanent pacemaker implantation where transfemoral TAVI was implanted between 2021 and 2023. In case new-onset complete LBBB was present after TAVI, an EP study was performed. EP study was considered positive when His-Ventricule interval was more than 70ms, or after procainamide infusion at 10mg/kg, more than 100ms or more than double the basal HV interval. In case EP was positive, a permanent pacemaker was implanted. In case EP was negative, a 30-day follow-up with ECG long-term monitoring system (Nuubo) was performed.

Results
In this cohort, 266 patients without pacemaker following TAVI were included. Persistent new-onset left bundle branch block was present in 10,15% of patients (n=27). EP study was positive in 29.62% of patients (n=8), following a definite pacemaker implantation. During follow-up, only one patient (12.5%) was dependent of ventricular stimulation. The group with negative EP study (n=19) were monitored with a 30-day ECG long-term monitoring system (Nuubo). No bradyarrhythmic events were registered in this group.

Conclusions
Approximately one tenth of patients develop persistent new-onset LBBB after TAVI. Events were seldom in both study groups. Positive EP study patients were dependent of ventricular stimulation in 12.5% of cases, and there was no bradyarrhythmic event registered in EP negative group. EP study could be a safe tool to stratify AVB risk in new-onset LBBB following TAVI.
Predictor of A4-amplitude using preprocedural electrocardiography in patients with leadless pacemakers
Authors: Kawatani S , Kotake Y , Takami A , Nakamura K , Tomomori T , Okamura A , Kato M , Yamamoto K 
Published: October 2024

Abstract

Background
Based on the historical studies of leadless pacemakers (LP), high atrio-ventricular synchrony (AVS) with mechanical sensing-based VDD pacing is largely influenced by A4-amplitude. A limited study investigated the predictors of A4-amplitude using clinical and echocardiographic parameters.

Objective
This study aimed to investigate the predictors of A4-amplitude preoperatively to select patients who could benefit the most from AVS among patients with VDD LPs.

Methods
Data from patients who received VDD LP implantations from November 2021 to August 2023 at our institution were analyzed. Twelve-lead electrocardiography and transthoracic echocardiography were performed before VDD LP implantations. To assess the electrical indices associated with the A4-signal, the electrocardiographic morphological P-wave parameters were analyzed including the P-wave duration, P-wave amplitude, maximum deflection index (MDI), and P-wave dispersion.

Results
A total of 50 patients who underwent VDD LP implantations (median age, 84 years; 64% male) were included and divided into two groups based on the median value of A4-amplitude, the high-A4 group (A4-amplitude &gt;2.5m/s2, n=26) and low-A4 group (A4-amplitude ≤2.5m/s2, n=24). There was a significant difference between the high-A4 and low-A4 groups in the LVEF (P=0.01), P-wave dispersion (P=0.01), and MDI (P&lt;0.001). A multivariate logistic analysis revealed that a lower MDI was an independent predictor of a high A4-amplitude (odds ratio: 0.78, 95% confidence interval: 0.67 to 0.92; P=0.003).

Conclusion
Preoperative electrocardiographic evaluations of the P-wave morphology may be useful for predicting A4-amplitude. The MDI was the only independent A4-amplitude predictor that seemed promising for selecting VDD LP patients.abstract figure
Discovering an unknown risk. The unnoticed, potientially life-threatening risk to people with an inherited cardaic arrhythmia during the non-cardiac perioperative period.
Authors: Mcglinchey L , Barr O , Cook N 
Published: October 2024

Abstract

Background
Patient safety is a global goal. Known risks to patient safety are a challenge however, that challenge is significantly increased when a risk is unknown but exists. It is estimated that 18 million major surgeries in Europe are non-cardiac surgical procedures. Preventable adverse events remain a challenge within healthcare systems worldwide. Potentially life-threatening conditions such as inherited cardiac arrhythmias (ICA) can be triggered by a number of factors during the perioperative phase. Healthcare professionals’ lack of knowledge, awareness or confidence about risks associated with ICAs during non-cardiac surgical procedures may have an impact on patient safety and quality of care for people with an ICA.

Purpose
To determine the knowledge and experience of ICA by healthcare professionals, their views towards and confidence in caring for a person with an ICA in a surgical environment.

Method
A multiple method study using a twenty-four-item questionnaire was distributed to registered nurses and midwives, surgeons and anaesthetists within surgical areas of seventeen hospitals in the Republic of Ireland and Northern Ireland of which 154 were returned and nine qualitative face to face interviews with registered nurses, midwives, and anaesthetists within surgical areas of one hospital in the Republic of Ireland and one hospital in Northern Ireland.

Results
Triangulation and convergence of data found a lack of knowledge in relation to inherited cardiac arrhythmias the study focused on, Long QT syndrome, Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) and Brugada syndrome. Within this, it was reported that 88.4% of participants were not aware of the drugs to avoid lists. Of those who were aware, 11.6%, no surgeon reported being aware of the drugs to avoid lists. It was also reported that participants had no confidence to care for people with an ICA in surgical settings. Years since graduation did not equate to an increase in confidence to care for these conditions. Participants reported reliance on the anaesthetist to be knowledgeable, manage care or take the lead should an adverse event occur. However, only seven of the nineteen anaesthetists who took part were aware of the drugs to avoid lists for ICA.

Conclusions
This study has found a lack of knowledge and confidence relating to inherited cardiac arrhythmias in surgical settings. It also highlighted that anaesthetists are seen as the professional to go to, however they may be unaware of this. Many surgeries take place globally which have the potential to induce an adverse event in people with an ICA that may result in death. This study has found an unknown blind spot which is a serious patient safety issue and a hazardous medical risk factor.
Significance of J wave with inverted ST-T polarity induced by ill-timed atrial premature beats and its association with Torsade de Pointes in patients with acute acquired long QT syndrome
Authors: Ichiryu H , Takasugi N , Wakasa S , Ishihara T , Masuda Y , Naruse G , Watanabe T , Yamada Y , Kanamori H , Okura H 
Published: October 2024

Abstract

Background
When ventricular cardiomyocytes become depolarized during their relative refractory period (RRP), the amplitude of the action potential (AP) becomes lower than that of preceding AP, since some sodium channels are in their refractory state. If the membrane voltage does not reach a level high enough to activate voltage-dependent calcium channels, the AP duration becomes markedly shortened due to loss of AP dome. In patients with long QT syndrome (LQTS), intrinsic differences in AP duration and/or AP restitution kinetics exist between ventricular endocardium and epicardium. Thus, we hypothesized that atrial premature beats (APBs) can capture the RRP and amplify a transmural voltage gradient that manifests as a J wave with inverted ST-T polarity (APB-induced J wave).

Purpose
To investigate the prevalence of APB-induced J wave and examine the contribution to the development of Torsade de Pointes (TdP) in patients with acute acquired LQTS.

Methods
A total of 34 consecutive patients with acute acquired LQTS (14 men; median age, 69 years; median QTc, 645.5 ms) and documented TdP were enrolled. APBs were observed before the onset of TdP in 18 (52.9%) patients. The 34 patients were divided into 2 groups based on the presence or absence of APB-induced J wave with inverted ST-T polarity: APB-J wave group (n=8) and non-APB-J wave group (n=26).

Results
APB-J wave group constituted 23.5% (8/34) of the studied patients. There were no significant differences in clinical characteristics (sex, age and QTc) between the 2 groups. Macroscopic T-wave alternans was more frequently observed before TdP onset in APB-J wave group than non-APB-J wave group (75% vs 15.4%, p=0.003). The ill-timed APBs with J wave directly initiated TdP in all patients in APB-J wave group. APB-J wave group experienced TdP even after initiating conventional therapy more frequently than non-APB-J wave group (3.5 vs 1 event, p=0.04).

Conclusions
APB-induced J wave is observed in approximately one-fourth of acute acquired LQTS patients with TdP and is associated with an increased risk of TdP. Our observations suggest that APBs can amplify the transmural dispersion of repolarization manifested as a J wave.Figure1Figure2
Risk factors for fatal ventricular arrhythmias in heart failure with preserved ejection fraction: a report from the CHART-2 Study
Authors: Ito T , Noda T , Nochioka K , Shiroto T , Yamamoto N , Sato H , Chiba T , Hasebe Y , Nakano M , Takahama H , Takahashi J , Shimokawa H , Yasuda S 
Published: October 2024

Abstract

Background
Fatal ventricular arrhythmia events (FAE), such as sustained ventricular tachycardia (VT) and ventricular fibrillation (VF), along with sudden cardiac death (SCD), represent serious complications in patients with heart failure (HF). While individuals with severely reduced left ventricular ejection fraction (LVEF), particularly below 35%, are deemed at high risk for lethal arrhythmic events and are considered for implantable cardioverter-defibrillator (ICD) therapy, recent studies have highlighted the occurrence of FAE or SCD in heart failure with preserved ejection fraction (HFpEF) as well. However, the specific risk factors for FAE or SCD in patients with HFpEF remain inadequately elucidated.

Purpose
This study aimed to investigate the incidence of FAE or SCD and identify their associated risk factors in patients with HFpEF.

Methods
We retrospectively analyzed the data from our multicenter observational study, the CHART-2 Study, where a total of 10,219 patients were enrolled between 2006 and 2010. Among them, we included patients with HF and LVEF≥50% (n=2,423) with available LVEF data at one year (Figure 1A). They were categorized into two groups based on LVEF status; 198 with decreased LVEF (35-50%; D-group) and 2,225 with preserved LVEF (≥50%; P-group). The primary endpoint was the composite event of FAE or SCD, and all statistical analyses were adjusted for competing risks due to all-cause mortality.

Results
Among the 2,423 patients with HFpEF (mean age: 69±12 years, 35% female), 120 patients (5.0%) experienced the composite event of FAE or SCD during a median follow-up of 9.1 years (interquartile range: 4.5-11.2 years), with a cumulative incidence of 5.1% at 10 years. Gray’s test revealed a significantly higher incidence of the primary endpoint in the D-group compared with the P-group (10.6% vs. 4.5% at 10 years, p&lt;0.001, Figure 2A). Multivariable analysis identified mild decline of LVEF (Hazard Ratio [HR] 2.20, 95% confidence interval [CI] 1.34-1.60; p=0.002) and non-sustained VT (HR 2.33, 95% CI 1.37-3.97; p=0.002) as independent risk factors for composite event. Landmark analysis demonstrated a consistent trend in the composite event of FAE or SCD in both groups (Figure 2B).

Conclusion
In patients with HFpEF, even a mild decline in LVEF, which typically does not prompt ICD consideration, was significantly associated with a heightened risk of FAE or SCD. Therefore, a chronological clinical assessment, encompassing changes in LVEF, is essential for patients with HFpEF.
Regional cardiac denervation predicts sustained ventricular arrhythmias in non-ischemic cardiomyopathy patients without LGE on CMR imaging
Authors: Jungen C , Chen S , Wijnmaalen A P , Dibbets-Schneider P , Piers S , Kimura Y , Androulakis A F A , Van Der Geest R , De Geus-Oei L , Scholte A H J A , Lamb H J , Jongbloed M R M , Zeppenfeld K 
Published: October 2024

Abstract

Background
In patients with non-ischemic cardiomyopathy (NICM) and no late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR), risk prediction for the occurrence of sustained ventricular arrhythmias (VA) is challenging. Global and regional sympathetic denervation has been associated with VA in patients with ischemic cardiomyopathy. Its prognostic relevance in NICM is unknown.

Purpose
To assess the risk prediction of sympathetic denervation for the occurrence of VA in NICM patients without LGE.

Methods
Consecutive patients from the ‘Leiden Nonischemic Cardiomyopathy Study’, who underwent programmed electrical stimulation, LGE-CMR and 123I- MIBG imaging between 2011-2018 were included. The presence of LGE and global and regional sympathetic denervation on 123I- MIBG was evaluated and patients were followed for occurrence of VA. Global denervation was assessed using the heart-to-mediastinum ratio. Regional denervation was evaluated by calculating the number of denervated segments (DS), the ratio of DS, the summed defect score and the weighted denervation size.

Results
Of 75 included patients (63 years [52-68], 79% male, LVEF 36% [27-44], 37% inducible for VA) 35 had no LGE. During 4.5±1.6 years follow-up, VA occurred in 8/35 (23%) patients without LGE and in 18/40 (45%) patients with LGE. Among patients without LGE, those with VA had greater regional sympathetic denervation (number of DS 8 [8-10] vs. 2 [1-5], P=0.004; ratio of DS 0.5 [0.5-0.7] vs. 0.2 [0.1-0.4], P=0.007; defect score 36 [31-41] vs. 18 [14-24], P=0.01; weighted denervation size 47 [39-53] vs. 22 [16-30], P=0.01).
In univariable analysis the number of DS (HR 1.25, 95% CI 1.06–1.46, P=0.006) was associated with the occurrence of VA in patients without LGE. Denervation of ≥ 7 segments identified patients without LGE at risk for VA (AUC: 0.83, sensitivity: 88%; specificity: 89%). Among patients with LGE, innervation state was not associated with VA during follow-up.

Conclusions
In NICM patients without LGE the extent of regional denervation may contribute to risk stratification for VA.Graphical Abstract
A risk score for ventricular arrhythmia in mitral valve prolapse
Authors: Syed F , Diamond J , Cesmat A , Chaudry A , Gupta S , Weickert T , Simpson R 
Published: October 2024

Abstract

Background
Prior studies have identified that complex and frequent ventricular ectopy (cfVE) predicts sudden death in patients with mitral valve prolapse (MVP).

Purpose
To develop a risk stratification score which predicts rates of cfVE in patients with MVP based on clinical, ECG and echocardiographic features.

Methods
Data was collected on 637 patients aged 18–90 years with MVP at our institution between 2016-2019. Complex and frequent ventricular ectopy was defined as the presence of &gt; 1% premature ventricular contraction (PVC) burden or non-sustained ventricular tachycardia on Holter monitoring or &gt; 1 PVC on 12-lead ECG. Univariate analysis was performed to identify independent predictors of cfVE. Factors found to be statistically significant on univariate analysis were then evaluated using multivariate logistic regression. Variables analyzed included age greater than 65, moderate or greater mitral regurgitation, female gender, African American race, atrial fibrillation, coronary artery disease, congestive heart failure, inferior or lateral T wave inversion, bileaflet (vs. unileaflet) prolapse, myxomatous mitral valve morphology, mitral annular dysjunction, left ventricular ejection fraction less than 40%, left ventricular hypertrophy, diabetes, and hypertension. Risk points were attributed to multivariate predictors of cfVE using their odds ratios. Predicted probability of cfVE, derived by logistic regression, was used to categorize scores into low, moderate, and high risk. Rates of cfVE were compared between risk groups using Pearson’s Chi-squared test. All-cause mortality was compared between risk score groups with Kaplan-Meier analysis.

Results
Complex and frequent ventricular ectopy was present in 182 (28.6%) patients. Multivariate predictors of cfVE were mitral annular disjunction (MAD, OR 3.2, 95% CI 1.9-5.4), bileaflet (vs. unileaflet) prolapse (OR 2.1, 95% CI 1.4-3.3), congestive heart failure (OR 2.2 95% CI 1.3-3.7) and inferior or lateral T wave inversion (TWI, OR 2.1, 95% CI 1.3-3.2). Risk points of 1.5 for MAD and 1 for bileaflet prolapse, CHF and TWI were totaled to group patients into low (score 0, n=274, 43.0%), moderate (score 1-2, n=276 ,43.3%) and high (score 2.5-4.5, n=87,13.7%) risk groups. Rates of cfVE were 11.7% for low, 35.5% for moderate and 59.8% for high-risk groups (p&lt;0.0001). On Kaplan Meier analysis, risk group significantly correlated with mortality (p&lt;0.0008).

Conclusion
In patients with MVP this risk stratification tool, using the presence of mitral annular disjunction, bileaflet prolapse, history of congestive heart failure and T-wave inversion, represents a viable method of predicting risk of cfVE, which correlates with all-cause mortality.Univariate and multivariate analysisKaplan-Meier Curve