bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogenous atrial conduction in patients with hypertrophic cardiomyopathy and atrial fibrillation
Authors: Klis M , Gharaviri A , Vigneswaran V , Sim I , Bodagh N , Niederer S , O'neill M , Williams S E 
Published: May 2024

Abstract

Background/Introduction
Hypertrophic cardiomyopathy (HCM) is characterised by myocardial thickening, fibrosis, and disarray, affecting both ventricles and atria. This pathology extends to atrial tissue, potentially influencing conductivity and contributing to arrhythmias, notably atrial fibrillation (AF). Pulmonary vein isolation to treat AF in HCM patients yields less satisfactory results compared to other patient groups. Improved understanding of the pathophysiology of AF in HCM patients could improve treatment stratification and delivery.

Purpose
This study aims to analyse atrial conduction properties in HCM patients with AF, compared to age, body mass index and sex-matched control patients.

Methods
Pre-ablation electroanatomic mapping data from 10 HCM patients and a matched control group of patients with structurally normal hearts undergoing AF ablation was retrospectively analysed. All patients underwent pre-ablation electroanatomic mapping during proximal coronary sinus pacing. This data was analysed using OpenEP software to quantify voltage mapping, conduction velocity and wave collision points. Conduction velocity was calculated using both plane fitting and triangulation methods. Wave collisions were identified by calculating the percentage of points with conduction velocity field divergence values less than -1.5.

Results
HCM patients exhibited significantly reduced mean left atrial bipolar voltage and greater low voltage burden &lt;0.5mV than matched control patients (1.43mV vs. 2.14mV, p=0.0177; and 38.28% vs. 15.68%, p&lt;0.0001), (Figure 1A and B). Wave collision points were significantly more prevalent in the HCM group (5.4% vs. 1.6%, p=0.0004), indicating more heterogeneous conduction (Figure 1C). Figure 2 shows example of divergence map with local electrograms around wave collision points. Both methods of quantifying conduction velocity showed comparable results. While average conduction velocity showed no statistically significant difference (plane fitting method - 0.61m/s in HCM group vs. 0.64m/s in control group, p = 0.465; triangulation method - 0.61m/s in HCM group, 0.64m/s in control group, p=0.393), a trend toward lower velocities in HCM patients was observed (Figure 1D and 1E).

Conclusion
HCM patients demonstrate significantly lower bipolar voltage and significantly greater low voltage areas than matched control patients. Atrial conduction in patients with HCM is significantly more heterogenous than matched control patients. These findings highlight marked conduction abnormalities in HCM patients which are likely to contribute to AF pathogenesis.
Whole exome sequencing in young atrial fibrillation patients
Authors: Rudaka I , Vilne B , Kalejs O , Rots D , Trusinskis K , Gailite L 
Published: May 2024

Abstract

Background
Up to 10% of atrial fibrillation (Afib) patients develop the condition in the young age and in the absence of any related risk factors. Recent publications emphasized the importance of genetic testing in this population. However, the yield of the investigation is highly variable and ranges from 1 to 24% precents.

Purpose
The purpose of this study is to evaluate the prevalence of causative genetic variants in young Afib patients without risk factors and evaluate any structural changes of the heart.

Methods
We performed whole exome sequencing in 54 young (age of Afib onset less than 65 years) Afib patients without any Afib related risk factors (original cohort). Using ACMG guidelines we performed analysis of 349 previously described cardiomyopathy and arrhythmia associated genes. If a pathogenic (P) or likely pathogenic (LP) variant was found, a cardiac magnetic resonance imaging (CMR) was performed to exclude any structural abnormalities of the heart. We also extracted 107 young Afib patients without any risk factors from UK Biobank (UK Biobank cohort) and performed analysis of the same genes in the subgroup.

Results
The prevalence of P and LP variants was 24% (13 cases) in the original cohort and 8% (9 cases) in the UK Biobank cohort (p=0.006). We observed variants in cardiac structural and developmental genes only in both cohorts (Table 1 and 2). In the original cohort there were nine (17%) patients with P and LP variant in TTN gene. Moreover, five patients were positive for the same TTN variant NM_001267550.2:c.13696C&gt;T p.(Gln4566Ter). In six (46%) original cohort patients we observed structural changes of the heart on CMR – in five patients there was dilation of one or both ventricles and in one there was increased T1 mapping intensity of septal wall segments.

Conclusions
1. There is a high prevalence of pathogenic and likely pathogenic causative genetic variants in young atrial fibrillation patients without any risk factors. 2. All variants are localized in cardiac structural or developmental genes only. 3. There is a high grade of structural changes of the heart observed on cardiac magnetic resonance imaging in patients with monogenic atrial fibrillation.Table 1.WES data in original cohortTable 2.WES data in UK Biobank cohort
Obesity paradox in atrial fibrillation patients on oral anticoagulation therapy: a Korean nationwide cohort study
Authors: Lee K N , Soh M S , Park B H , Kim D Y , Roh S Y 
Published: May 2024

Abstract

Background
The obesity paradox is a phenomenon that has been observed in specific pathological conditions, wherein individuals who are overweight or obese exhibit a survival advantage over those with a normal weight. This phenomenon has also been noted in patients diagnosed with atrial fibrillation (AF), although the impact of body mass index (BMI) on clinical outcomes in AF patients undergoing oral anticoagulant (OAC) therapy remains uncertain.

Purpose
The aim of this study was to investigate the potential relationship between obesity and cardiovascular outcomes in patients diagnosed with AF who were receiving OAC.

Methods
We utilized administrative claims data from the Korean National Health Insurance Service and the combined health check-up database of the National Health Insurance Corporation to conduct a retrospective national cohort study spanning from 2013 to 2020. The patients newly prescribed OAC for AF were included, between January 2015 and December 2019. We followed up with patients from their index date until each outcome event or the end of the study period. BMI was categorized into 5 groups based on the World Health Organization's recommended criteria for Asian populations. The predefined clinical outcomes included thromboembolism, major bleeding, all-cause death, and the composite outcome.

Results
A total of 35,333 patients were included in the study. The mean age was 69 ± 10 years, and 37.1% were female. During a median follow-up of 2.0 years (IQR, 0.4–3.3), there were 11,634 thromboembolic events, 1,521 major bleeding events, and 2,586 deaths. The adjusted hazard ratio (HR) for thromboembolism, major bleeding, all-cause death, and a composite outcome were lower in obese II group (HR 0.79, 95% CI 0.73–0.86; HR 0.99, 95% CI 0.79–1.24; HR 0.75, 95% CI 0.62–0.91; HR 0.81, 95% CI 0.75–0.88) compared to the normal range BMI group.

Conclusions
In AF patients undergoing OAC therapy, individuals classified as obese exhibited a reduced risk of thromboembolism, major bleeding, all-cause mortality, and composite outcome compared to patients with normal weight.Adjusted hazard ratio of outcomes by BMI
Clinical significance of new-onset atrial fibrillation in patients with coronary artery or peripheral artery disease: results from the COMPASS trial
Authors: Benz A P , Alings M , Bosch J , Avezum A , Bhatt D L , Healey J S , Johnson L S , Mcintyre W F , Widimsky P , Yusuf S , Connolly S J , Eikelboom J W 
Published: May 2024

Abstract

Background
The COMPASS trial enrolled patients with coronary artery or peripheral artery disease, but excluded patients requiring oral anticoagulation. Compared to aspirin alone, rivaroxaban in addition to aspirin reduced a composite of cardiovascular death, stroke or myocardial infarction.

Purpose
This study aimed to explore the clinical significance of a new diagnosis of atrial fibrillation (AF) during follow-up.

Methods
New AF was identified from unplanned hospitalization, study drug discontinuation and adverse event reports. The associations between new-onset AF, clinical characteristics and outcomes in COMPASS participants were studied using time-updated regression modeling. Event rates were reported as per 100 patient-years (following a new diagnosis of AF vs. from randomization until the end-follow-up or new AF, whichever came first).

Results
During a mean follow-up of 23 months, 655 of 27,395 participants (2.4%) were newly diagnosed with AF. Advanced age, male sex, white race, higher body mass index, higher systolic blood pressure, heart failure and prior myocardial infarction were independently associated with new-onset AF. The rates of permanent discontinuation of study drug were 83.8% following a new diagnosis of AF, compared to 17.5% in participants without/before new AF. Compared to participants without/before a new diagnosis of AF, participants with new-onset AF were at increased risk of a composite of cardiovascular death, stroke or myocardial infarction (8.9 vs. 2.5 per 100 patient-years, hazard ratio [HR] 4.49, 95% confidence interval [CI] 3.37-6.00) (Figure 1). Risk increases with new-onset AF were also observed for hospitalization for heart failure (9.1 vs. 1.1 per 100 patient-years, HR 6.35, 95% CI 4.59-8.80) (Figure 2) and major bleeding (4.1 vs. 1.3 per 100 patient-years, HR 2.93, 95% CI 1.99-4.33).

Conclusion
In COMPASS, a new diagnosis of AF during trial follow-up was associated with a marked increase in risk of adverse outcomes.Composite outcome after new-onset AFHeart failure after new-onset AF
Atrial fibrillation after transcatheter tricuspid valve repair: rhythm control strategies and outcomes
Authors: Schipper J , Woermann J , Van Den Bruck J , Filipovic K , Dittrich S , Scheurlen C , Erlhoefer S , Pavel F , Iliadis C , Pfister R , Sultan A , Lueker J , Steven D 
Published: May 2024

Abstract

Background
Transcatheter tricuspid valve (TV) repair emerged as a viable treatment option in patients with severe tricuspid regurgitation and high operative risk. Although atrial fibrillation (AF) is common in these patients, the prognostic value of maintenance of sinus rhythm (SR) after transcatheter TV repair is unknown.

Purpose
We sought to assess the prevalence and efficacy of rhythm control strategies and impacts of maintenance of sinus rhythm on outcomes after transcatheter TV repair.

Methods
All patients undergoing transcatheter TV repair in our center between April 2017 and December 2022 were included in this single-center retrospective analysis. Patients who maintained SR throughout the follow-up (FU) were compared to patients who did not. The composite study endpoint included death from any cause, heart failure (HF) hospitalization and repeat TV repair. Furthermore, prevalence and efficacy of rhythm control strategies were evaluated.

Results
A total of 203 patients (mean age 78 ± 7 years, 145 (68 %) female) after transcatheter TV repair was analyzed. After a median follow-up of 12 months (IQR 4-20), 21 patients (10 %) did maintain SR. AF was present in 183 patients (90 %), of whom 134 had permanent AF. In the AF group, direct-current cardioversion (DCCV) was performed in 6 patients (3 %). Following DCCV, SR was restored in 4 patients (75 %), of whom 3 patients (75 %) presented in SR 30 days after DCCV. 2 patients (1 %) underwent AF ablation. After a case-control matching including 38 patients (SR vs. AF), during a median follow-up of 8 months (IQR 1-20) the study endpoint occurred in 7 of 19 patients (37 %) in the SR group and 12 of 19 patients (63 %) in the AF group (HR 0.70, p = 0.43).

Conclusions
The incidence of AF among patients undergoing transcatheter TV repair is high. In the present patient cohort, there was a trend towards a higher likelihood of death from any cause, HF hospitalization and repeat transcatheter TV repair in patients with AF. Further randomized studies are needed to evaluate the impact of rhythm control in patient undergoing TV repair.
Effects of sodium glucose co-transporter-2 inhibitor on atrial tachyarrhythmia burden in patients with cardiovascular implantable electronic device
Authors: Nantsupawat T , Apaijai N , Prommintikul A , Prasertwitayakij N , Chattipakorn S , Chattipakorn N , Wongcharoen W 
Published: May 2024

Abstract

Introduction
Previous studies showed that sodium glucose co-transporter-2 inhibitors (SGLT2i) were associated with a lower atrial fibrillation (AF) incidence.

Purpose
Since mitochondrial dysfunction has been linked with AF, we aimed to examine the effects of SGLT2i on AF burden and mitochondrial function in patients with cardiovascular implantable electronic device (CIED).

Methods
Patients with CIED were randomly assigned to receive either dapagliflozin 10 mg daily or placebo for 3 months. The AF burden was measured as atrial high-rate episodes (AHRE) via CIED interrogations, and data were collected at baseline and 3-months post-treatment. Oxidative stress and mitochondrial function were determined in peripheral blood mononuclear cells (PBMCs).

Results
The study enrolled 54 CIED patients. There were 9 (16.7%) patients with diabetes mellitus and 36 (66.7%) patients with history of clinical AF. The changes of AHRE burden after 3-month treatments did not differ between dapagliflozin and placebo groups. However, in those with clinical AF, dapagliflozin significantly decreased the number of AHRE per month as compared to placebo (-2.2 vs. +0.6 episodes per month, p=0.048) (Table 1). Mitochondrial spare respiratory capacity (SRC) percentage was significantly increased after treatment with dapagliflozin (162.1% to 203.2%, p=0.003), whereas this was not found in the placebo group (Figure 1). In the subgroup analysis of patients with clinical AF, dapagliflozin showed significant improvement in both the SRC percentage (165.7 to 201.7%, p=0.016) and a reduction in cellular oxidative stress (26,840.5 to 18,164.0 arbitrary unit, p=0.049).

Conclusions
Dapagliflozin significantly reduced the number of AHRE per month in patients with history of clinical AF. The improvement in PBMC’s mitochondrial function and reduced cellular oxidative stress among dapagliflozin users could be the mechanisms responsible for its anti-atrial arrhythmic effect.Table 1Figure 1
Presence and predictors of atrial low voltage zones in patients with non cardiovertable atrial fibrillation
Authors: Bergt I , Richter S R , Ebert M E , Mayer J M , Zedda A Z , Ulbrich S U , Dindane Z D , Richter U R , Gaspar T G 
Published: May 2024

Abstract

Background
Interventional treatment of persistent atrial fibrillation (pAF) presents a challenge due to the lack of clear evidence on adjunctive strategies beyond pulmonary vein isolation (PVI). One promising approach is ablation of left atrial low voltage zones, which has been shown to improve outcomes in patients with pAF. However, reliable assessment of left atrial endocardial voltage requires sinus rhythm (SR). In a significant proportion of patients with persistent atrial fibrillation (pAF) however, restoration of sinus rhythm (SR) cannot be achieved. These may lead to extensive ablations such as defragmentation or empirical isolation of the posterior wall of the left atrium. This study aims to investigate the potential of unsuccessful cardioversion prior ablation as a predictor for the presence of low voltage zones (LVZ) in the left atrium.

Methods
This retrospective, single-centre study was conducted on 264 patients (31,8% female; age: 67±10 years; mean AF duration: 1-2 years) diagnosed with pAF who underwent catheter ablation for pAF between 01/2017 and 01/2020. All patients underwent electrical cardioversion (CV) before ablation. If restoration of SR was achieved, high-density contact mapping was performed in sinus rhythm before pulmonary vein isolation (PVI), in case of unsuccessful initial cardioversion, high-density contact mapping was performed after repeated CV followed the PVI, respectively.

Results
Initial cardioversion was unsuccessful in 53 out of 264 (19.7%) patients. Subsequent to pulmonary vein isolation, cardioversion was successful in 47 out of 53 (81%) patients initially considered non-cardiovertible. In 32 out of 53 (60.4%) patients who had an initial unsuccessful cardioversion, no left atrial low voltage was identified. Amongst patients who underwent a successful initial cardioversion, left atrial low voltage zones were apparent in 77 out of 211 patients (36.5%). There is no significant difference in the the presence of left atrial low voltage between patients who had initially successful and unsuccessful CV (χ²(1) = 0.178, p = 0.673, φ = 0.026). According to the ROC analysis, the success of CV does not have any predictive value for LVZ (AUC 0.511).

Conclusion
Cardioversion failure before pulmonary vein isolation does not predict left atrial low-voltage zones (LVZ). PVI alone may be adequate even in patient with clinically "end stage" non-cardiovertible atrial fibrillation. Ablation beyond pulmonary vein isolation have the potential to overtreat this specific patient group, resulting in an increase in secondary arrhythmias. These findings indicate that even single-shot devices such as balloon-based techniques may be a considerable ablation strategy in these patient cohort.
Safety and efficacy of long-term sodium channel blocker therapy for early rhythm control: the EAST-AFNET 4 trial
Authors: Rillig A , Eckardt L , Borof K , Camm A J , Crijns J G M , Goette A , Metzner A , Schotten U , Wegscheider K , Zapf A , Heidbuchel H , Willems S , Schnabel R , Magnussen C , Kirchhof P 
Published: May 2024

Abstract

Background
Clinical concerns exist about the potential proarrhythmic effects of the sodium channel blockers flecainide and propafenone (SCB) in patients with cardiovascular disease.

Purpose
SCB were used to deliver early rhythm control (ERC) therapy in EAST-AFNET 4.

Methods
We analysed the primary safety outcome (death, stroke, or serious adverse events related to rhythm-control therapy) and primary efficacy outcome (cardiovascular death, stroke and hospitalization for worsening of heart failure or acute coronary syndrome) during SCB-intake for ERC patients (n=1395) in EAST-AFNET 4. The protocol discouraged flecainide and propafenone in patients with reduced left ventricular ejection fraction and suggested stopping therapy upon QRS prolongation &gt;25% on therapy.

Results
Flecainide or propafenone was given to 689 patients (age 69 (8) years; CHA2DS2-VASc 3.2 (1); 177 with heart failure; 41 with prior myocardial infarction, CABG or PCI and 26 with left ventricular hypertrophy &gt;15mm; median therapy duration 1,153 [237, 1,828] days). The primary efficacy outcome occurred less often in patients treated with SCB (3/100 (99/3,316) patient-years) than in patients who never received SCB (SCBnever 4.9/100 (150/3,083) patient-years, p&lt;0.001). There were numerically fewer primary safety outcomes in patients receiving SCB (2.9/100 (96/3,359) patient-years) than in SCBnever patients (4.2/100 (135/3,220) patient-years, adjusted p=0.015). Sinus rhythm at 2 years was similar between groups (SCB 537/610 (88); SCBnever 472/579 (82)).

Conclusion
Long-term therapy with flecainide or propafenone appeared to be safe in the EAST-AFNET 4 trial to deliver effective ERC therapy, including selected patients with stable cardiovascular disease such as coronary artery disease and stable heart failure.
Characterization of conduction recovery and atrial electrophysiological properties after pulmonary vein isolation using pulsed field ablation
Authors: Scharfe F , Karolyi L , Spitzer S , Langbein A 
Published: May 2024

Abstract

Background
Pulsed field ablation (PFA) is a relatively new technology for isolation of pulmonary veins in patients with atrial fibrillation (AF). Data addressing reasons for recurrent atrial fibrillation despite primarily successful pulmonary vein isolation (PVI) using PFA are scarce, due to an up to date limited number of patients treated this way.

Objective
The aim of this study was to analyze electrophysiological characteristics of reconduction and / or left atrial substrate of patients referred to our center for Re-Do procedures for recurrent AF after an initial PVI using PFA.

Methods
90 patients (mean age 66±9 years, 69 male (77%)) had been treated in our center from November 2021 to July 2023 with PVI using PFA. 9 (10%) of these patients were referred for Re-Do procedures. These were performed by radiofrequency ablation (RFA) using Carto system including high density mapping and high power / short duration (HPSD) ablation. We analyzed location of PV reconnection and low voltage areas (LVA) in the left atria.

Results
7 out of 9 patients (77%) presented with reconnections of pulmonary veins. In one patient a single vein showed reconduction (RSPV), in 5 patients 2 veins were conducting (1x LSPV, 3x LIPV, 1 left sided common os (LCo), 1x RSPV, 3x RIPV). None of the patients showed 3 or 4 reconnected veins. Areas of reconduction in each vein were: LSPV 1x ridge, 1x posterior; LIPV 1x posterior, 1x anterior and posterior; LCo 1x posterior, RSPV 1x anterior, 2x carina, 1x anterior and posterior; RIPV 1x complete, 2x carina. In 7 patients a fibrotic atrial cardiomyopathy (FACM) was diagnosed via high density mapping of LVA’s. In 2 of these patients all 4 pulmonary veins were chronically isolated after the initial PVI. All patients except one (very small anterior LVA) with FACM ≥1 were treated with additional linear or encircling lesions according to the individual extent of the fibrotic areas. 2 patients had no LVA’s detectable. In one of those 2 patients 2 veins had reconnected. The other patient had chronically isolated veins (no proof of dormant conduction with adenosine) and no detectable non-PV-triggers under isoprenaline.

Conclusion
In the population of patients undergoing PVI using PFA in our center, only 10% had clinically relevant recurrences leading to the necessity of a Re-Do procedure. Most patients (77%) in this setting had reconnections of pulmonary veins. There is a tendency of posterior reconnections of the left pulmonary veins and reconnections of the carina of the right pulmonary veins, but the number of patients is too small to clearly define predilection sites that have to be paid attention to when using PFA. Additionally, left atrial substrate is an important problem in patients with recurrent AF despite primarily successful PVI and has to be considered and thoroughly addressed in Re-Do procedures.Reconnection of LSPV and anterior LVAAblation of RSPV and LSPV (posterior)