bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship between electrical activity and left atrial volume during atrial fibrillation
Authors: Adragao P , Nascimento Matos D , Costa FM , Galvao Santos P , 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.

Introduction
Pulmonary veins (PV) ostia were previously identified as the left atrium (LA) areas with the shortest refractory period during sinus rhythm. Pulmonary veins isolation (PVI) became standard of care, but clinical results are still suboptimal. Currently, atrial fibrillation (AF) cycle length mapping (CLM) is possible due to a special tool of the Carto® electroanatomical mapping, which identifies areas in the left atria with shortest refractory period, during AF.

Purpose
Using this new EAM feature, our study aimed to assess the relationship between short refractory period LA areas and left atrial volume and AF type, known predictors of AF relapse.

Methods
Retrospective analysis of an unicentric registry of individuals with symptomatic drug-refractory AF who underwent PVI AF ablation with Carto® EAM. CLM was performed. CL maps were created with a high-density mapping Pentaray® catheter before and after PVI. We assessed areas of short cycle length (SCL) (defined as 120 to 250ms), and their relationships with complex fractionated atrial electrograms (CFAE), and low-voltage zones (from 0.1 to 0.3mV).

Results
A total of 35 patients (21 men, median age 62 IQR 53-71 years) were included. Most patients presented with persistent AF (n=23, 66%), and 8 patients (23%) had a previous PVI. The mean shortest measured cycle length in AF was 134ms (SD ± 23ms). There was a negative correlation between LA volume and SCL areas after PVI (Spearman Correlation coefficient [ρ] = - 0.47, P = 0.037). There was no correlation between LA volume and SCL areas before the PVI procedure (ρ = -0.06, P = 0.776), nor between AF type and SCL (ρ = -0.118, P = 0.620). All patients presented areas of SCL located in the PVs or their insertion, 76% in the posterior/roof region adjacent to the left superior pulmonary vein (LSPV) and 76% in the anterior region of the wall adjacent to the right superior pulmonary vein (RSPV). These two areas remained the fastest even after PVI. The anterior mitral region rarely presented SCL (16%). SCL were related to low-voltage areas in 93% and were adjacent to CFAE in 84% of the cases. Low-voltage areas and CFAE were more frequent and had a larger LA dispersion than SCL.

Conclusion
Our study shows that LA volume, not AF type, is correlated with remaining SCL areas after a pulmonary vein isolation procedure. This finding suggests a possible causal link between increased LA volume and AF relapse post-PVI. More studies are needed to assess the role of the SCL areas as a potential ablation target and their impact on AF ablation outcomes.
Thawing plateau time indicating the duration of phase transition from ice to water is the strongest predictor for long-term durable pulmonary vein isolation after cryoablation for atrial fibrillation
Authors: Shi LB , Chu SY , Wang YC , Solheim E , Schuster P , Chen J 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): Helse Vest, Norway (LBS), and the Research Council of Norway (SYC).

Background
Cryoballoon ablation is an important method for pulmonary vein (PV) isolation in treatment of atrial fibrillation (AF). Previous studies have shown that thawing time, but not freezing time or temperature, impacts PV reconnection during long-term follow-up. However, it is unknown whether the entire or only part of the thawing stage plays a critical role.

Purposes
This study aimed to clarify the relationship between the durability of PV isolation and the time of phase transition from ice to water indicated by thawing plateau (TP) time during a cryoballoon ablation.

Methods
In this retrospective study, 241 PVs from 71 patients who underwent a repeat AF ablation 526 (IQR: 412, 675) days after a cryoballoon ablation were analyzed. The predictive value of procedural parameters for the durability of PV isolation were evaluated. Definitions of different phases of the temperature-time curve are shown in Figure 1. TP Time is defined as the time from 0 to 10°C inside the balloon in the thawing period (the plateau on the curve).

Results
Reconnection was observed in 101 (41.9%) PVs of 53 patients (74.6%). Durable PV isolation was associated with significantly longer TP Time compared with PV reconnection (26.0 vs. 11.0 s, P&lt;0.001). The proportion of durable PV isolations increased with TP Time in a dose-proportional manner (Figure 2). The cut point for PV reconnection was TP Time &lt;15 s with a positive predictive value of 82.1% (sensitivity=63.4%, specificity=90.0%) while for durable PV isolation the cut point was TP Time &gt;25 s with a positive predictive value of 84.6% (sensitivity=55.0%, specificity=86.1%). After the analysis of multivariable logistic regression, location of PV (P&lt;0.01), and TP Time (P&lt;0.05) were shown as independent predictors for durable PV isolation. None of nadir temperature, initial cooling time, effective freezing time, initial thawing time, or late warming time was independent predictor. Accumulated TP Time for all PVs showed a positive linear correlation with the plasma level of troponin T (ρ=0.624, P&lt;0.01).

Conclusions
TP Time is an independent predictor for the durability of PV isolation, and it presents in a dose-proportional manner. TP Time &lt;15 s predicts long-term reconnection while TP Time &gt;25 s predicts durable PV isolation.
Impact of sleep apnea treatment with CPAP on recurrence of atrial fibrillation after catheter ablation
Authors: Antunes Coelho R , Parreira L , Farinha J , Esteves A , Pinheiro A , Ferreira J , Quintal J , Amador P , Marinheiro R , Mesquita D , Caria R 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None. Main funding source(s): None

Background
Sleep apnea, as well as other risk factors such as obesity and high blood pressure, increase the risk of recurrence of atrial fibrillation after catheter ablation. But the true impact of sleep apnea treatment on recurrence of atrial fibrillation is less well defined.

Purpose
Assess the impact of untreated sleep apnea and treatment with CPAP (continuous positive airway pressure) on the risk of atrial fibrillation recurrence in patients undergoing catheter ablation.

Methods
We performed a retrospective analysis of 160 patients undergoing catheter ablation of paroxysmal or persistent atrial fibrillation in our institution, in a period between November of 2015 and November of 2021. We compared two groups: with atrial fibrillation recurrence and without atrial fibrillation recurrence, in a follow-up period of eighteen months. We analysed the clinical characteristics, diagnosis of sleep apnea, treatment with CPAP, echocardiographic findings (indexed volume of left atrium and left ventricular ejection fraction), cardiovascular risk factors and other comorbidities (table 1). Survival analysis of atrial fibrillation recurrence was performed using a Cox Regression analysis (figure 1).

Results
During a mean follow-up time of 22,8 ± 19,9 months, 46 patients (28,8%) had atrial fibrillation recurrence and none died. The recurrence was associated with hypertension, alcohol habits and untreated sleep apnea. Untreated sleep apnea was associated with a 4-fold increased risk of atrial fibrillation recurrence (HR 3,74; 95% CI 1,89-7,42; p &lt;0,001). In patients with sleep apnea (n = 41), CPAP treatment was associated with a 74% decreased risk of recurrence (HR 0,26; 95% CI 0,10-0,72; p = 0,009).

Conclusions
Treatment with CPAP was associated with lower risk of recurrence of atrial fibrillation after catheter ablation in patients with sleep apnea.
P-wave duration and atrial fibrillation recurrence after catheter ablation, a systematic review and meta-analysis
Authors: Koutalas E , Intzes S , Zagoridis K , Symeonidou M , Spanoudakis E , Arya A , Dinov B , Dagres N , Hindricks G , Bollmann A , Kanoupakis E , Kochiadakis G , Nedios S 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Atrial fibrillation (AF) is a global health problem with high morbidity and mortality. Catheter ablation (CA) can reduce AF burden and symptoms, but AF recurrence (AFr) remains an issue. Simple AFr predictors like P-wave duration (PWD) could help improve AF therapy.

Purpose
This updated meta-analysis reviews the increasing evidence for the association of AFr with PWD and offers practical implications.

Methods
Publication databases were systematically searched and cohort studies reporting PWD and/or morphology at baseline and AFr after CA were included. Complete interatrial block (cIAB) was defined as PWD≥120 ms and biphasic morphology in inferior leads. Random-effects analysis was performed using the Review Manager 5.3 and R programs after study selection, quality assessment and data extraction, to report odds ratio (OR) and confidence intervals (CI).

Results
Among 4175 patients in 22 studies, 1138 (27%) experienced AFr. Patients with AFr had longer PWD with a mean pooled difference of 7.8 ms (19 studies, p&lt;0.001)(Figure 1). Pooled OR was 2.04 (1.16-3.58) for PWD&gt;120 ms (13 studies, p=0.01), 2.42 (1.12-5.21) for PWD&gt;140 ms (2 studies, p=0.02), 3.97 (1.79-8.85) for cIAB (6 studies, p&lt;0.001) and 10.89 (4.53-26.15) for PWD&gt;150 ms (2 studies, p&lt;0.001)(Figure 2). There was significant heterogeneity but no publication bias detected.

Conclusion
PWD is an independent predictor for AF recurrence after LA ablation. The AFr risk is increasing exponentially with PWD prolongation. This could facilitate risk-stratification by identifying high-risk patients (cIAB, PWD&gt;150 ms) and adjusting follow-up or interventions.
Prevalence and clinical impact of major incidental findings detected on routine cardiovascular resonance imaging prior to catheter ablation of atrial fibrillation
Authors: Richter S , Ebert M , Karrengarn R , Oebel S , Doering M , Kircher S , Jahnke C , Hindricks G , Paetsch I 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Preprocedural contrast-enhanced cardiovascular magnetic resonance (CMR) or computed tomography (CT) imaging of the left atrium (LA) and pulmonary veins (PVs) is usually employed to facilitate catheter mapping and ablation of atrial fibrillation (AF). Incidental findings (IFs) are common on cardiac imaging prior to AF catheter ablation (AFCA). However, previous studies were of small size and have mainly focused on radiological extracardiac IFs detected on preprocedural CT scan.

Purpose
To assess the prevalence of major cardiac and extracardiac IFs on routine preprocedural CMR in a large cohort of consecutive patients scheduled for first-time AFCA, and to report its impact on clinical decision-making and management.

Methods
All consecutive patients who underwent routine preprocedural CMR prior to first-time AFCA between April 2015 and March 2019 were considered for analysis. Main exclusion criteria were referral for repeat AFCA; prior cardiac CT or CMR imaging; and general contraindication to CMR or AFCA. All CMR examinations consisted of survey images with full thoracic coverage, cardiac cine and late-gadolinium enhancement imaging, and three-dimensional contrast-enhanced CMR angiography of the LA/PVs. An IF was defined as major when any newly detected finding either resulted in cancellation of the AFCA procedure or intentional deviation from the standard AFCA protocol. In patients with accessory or anomalous PVs the ablation strategy was individually tailored aiming at isolation of all PVs.

Results
Two thousand consecutive patients (62±10 years; 59% male) with paroxysmal (48%) or persistent (52%) AF were included. Among the entire study cohort 172 patients (8.6%) had a total of 184 cardiac (75%) and extracardiac (25%) major IFs (Fig. A+B). Preprocedural detection of a major IF resulted in cancellation of the scheduled AFCA procedure in 88 patients (4.4%). Forty-two patients (2.1%) have thereupon never been ablated, 46 patients (2.3%) underwent postponed AFCA after a median time from CMR imaging of 83 (32-213) days. The remaining 84 patients with major IF (4.2%) underwent an individualized approach to AFCA (Fig. A). The most common major IFs were accessory or anomalous PVs in 76 (3.8%), extracardiac abnormalities suspicious of malignancy in 29 (1.5%), and positive stress perfusion imaging in 19 (1.0% overall; 7.2% of 261 tested) patients. In 19 patients (1.0%) preprocedural CMR detected a previously unknown intracardiac thrombus or structural cardiac disease.

Conclusion
Unexpected major IFs on routine preprocedural CMR affected clinical decision-making and therapeutic management in 8.6% of patients scheduled for first-time AFCA at our institution. Whether preprocedural CMR imaging may improve safety and outcome of AFCA needs to be addressed in future research.
Optimization of a care pathway before atrial fibrillation ablation with the integration of translational research into routine clinical care
Authors: Verhaert D , Linz D , Wassink GW , Weijs B , Philippens S , Luermans JGLM , Westra SW , Schotten U , Vernooy K , Den Uijl DW 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The diagnostic work-up for atrial fibrillation (AF) catheter ablation is often complex and expensive. Improving the organization of this work-up may help to streamline patient journeys and to reduce administrative burden and costs. Additionally, reorganizing the existing work-up provides the opportunity to integrate (translational) research into routine clinical care, hereby contributing to improved patient selection and improved care for future patients.

Purpose
The aim of this project was to optimize a care pathway for patients considered for AF ablation, with the goals to improve the patient journey and simultaneously integrate research into the clinical process.

Methods
The Lean Six Sigma approach was used to map the pre-existing process, identify constraints in the process and formulate countermeasures. The impact of this pathway optimization was evaluated using four outcome measures: (1) efficient use of medical resources, defined as the percentage of patients receiving the pre-ablation work-up and eventually undergoing AF ablation, (2) number of hospital visits and consultations with a cardiologist, (3) pathway compliance, defined as the percentage of patients that completed the work-up with a maximum of 2 outpatient hospital visits, a maximum of 1 cardiologist consultation, laboratory results available, and a complete echocardiogram available, and (4) completeness of scientific data, defined as the availability of a predefined set of relevant variables (clinical indicators, medication, laboratory results and echocardiography derived data).

Results
Five root causes for constraints in the pre-existing work-up were identified and corresponding countermeasures were formulated (Figure 1). The impact of the countermeasures was studied for 33 patients before and 26 patients after pathway optimization. After optimization, efficient use of resources increased from 44% to 95% (p&lt;0.01). The project resulted in fewer hospital visits per patient (3.2 ±1.2 versus 2.3 ±0.8, p=0.01) and fewer cardiologist consultations (1.8 ±0.7 versus 1.0 ±0.3, p&lt;0.01). Pathway compliance increased significantly (3% versus 73%, p&lt;0.01), an increase that was reflected in all separate components of overall pathway compliance (Figure 2, panel A). The percentage of available data for scientific research increased from 80% to 94% (p&lt;0.01), resulting in a complete dataset in 73% of patients after, compared to only 15% of patients prior to the optimization project (p&lt;0.01, Figure 2, panel B).

Conclusions
This optimization project resulted in a more efficient care pathway for patients considered for AF ablation. The structural integration of research into the care pathway may lay the foundations for further improvements of AF care in the future.
The impact on renal function after long-term use of anticoagulants in atrial fibrillation patients
Authors: Lee WC 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: Private hospital(s). Main funding source(s): This study was supported by the research program of the Chang Gung Memorial Hospital.

Objective
Long-term oral anticoagulant should be considered or recommended in patients with atrial fibrillation (AF) and CHA2DS2VASc score ≥1 for stroke prevention. Warfarin and different direct oral anticoagulants (DOACs) are metabolized differently by the kidney. The impact on renal function after long-term use of anticoagulants in the patients with AF remains unclear. This study aimed to compare DOACs and warfarin’s impact on the decline in renal function from a large cohort with AF.

Methods
This study included patients with nonvalvular AF from 2000 to 2018, mainly through the medical history (ICD code) of the Chang Gung Research Database. Baseline estimated glomerular filtration rate (eGFR), follow-up eGFR and the change in eGFR between 2-year eGFR and baseline eGFR were compared between different DOACs and warfarin after propensity score matching. The primary study endpoint was acute kidney injury (AKI).

Results
3657 patients were enrolled in this study and the mean observation time was 3.3 ± 0.9 years. During the observation period, there was a significantly higher incidence of AKI during follow-up in the warfarin group than in the different DOAC groups before and after propensity score matching (before: warfarin vs. DOAC: 9.2% vs. 5.2%, p&lt;0.001; after: warfarin vs. DOAC: 8.9% vs. 4.4%, p&lt;0.001). There was no difference in the incidence of AKI between dabigatran group and anti-factor Xa inhibitor group after propensity score matching. The incidence of AKI was similar among rivaroxaban, apixaban and edoxaban groups after propensity score matching. The change in eGFR between 2-year eGFR and baseline eGFR did not differ between the warfarin and DOAC groups after propensity score matching (warfarin vs. DOAC: -1.27 ± 20.32 vs. -1.94 ± 17.24 mL/min/1.73 m2, p=0.461).

Conclusions
During the mean observation time of 3.3 ± 0.9 years, warfarin was associated with a higher incidence of AKI compared with DOACs. The decline in renal function did not differ among warfarin and different DOAC groups.
Patients’ perspective on a pill-in-the-pocket oral anticoagulation as an alternative stroke prevention strategy in atrial fibrillation
Authors: Briosa E Gala A , Pope MTB , Leo M , Lobban T , Betts TR 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Introduction
Oral anticoagulation (OAC) decisions are binary: if atrial fibrillation (AF) is detected and additional risk factors are presented, lifelong continuous OAC is recommended regardless of AF burden or temporal patterns. AF-related stroke risk appears to be lower in patients with paroxysmal AF and, therefore, indefinite OAC may have limited benefit whilst exposing patients to a significant bleeding risk. ‘Pill-in-the-pocket’ OAC during and shortly after AF challenges this dichotomous approach to OAC and is being explored in several pilot studies as an alternative AF-related stroke prevention strategy.

Purpose
This patient questionnaire sought to examine patients’ perspective of ‘pill-in-the pocket’ OAC strategy.

Methods
An 8-question interactive survey was developed in collaboration with AF Association (UK based charity) and included a short description of implantable cardiac monitors main features, implant procedure and associated risks. The survey was available online on the AF Association website from 30/09/2020 to 2/11/2020.

Results
Overall, 321 participants with an underlying diagnosis of AF replied to the online survey over the course of four and half weeks. The majority (82%) were taking direct oral anticoagulants. Just over two thirds of patients had concerns regarding bleeding side-effects from taking OAC and, approximately, a quarter had experienced a bleeding event (1.5% major bleeding and 24.2% minor bleeding). When asked if it was shown to be safe to monitor their heart rhythm continuously and take anticoagulants only during an episode of AF and for a small number of days afterwards (i.e. ‘pill-in-the-pocket’), 53.7% of participants would use guided by an implantable cardiac monitored. Slightly lower number of patients (48%) would take pill-in-the-pocket oral anticoagulation guided by a wearable device. In the comments the main reasons not to pursue ‘pill-in-the-pocket’ were permanent AF, previous thromboembolic events and concerns regarding reliability of monitoring technologies. In contrast, those who were receptive to this alternative approach had previous bleeding episodes, had very infrequent AF episodes and wanted to reduce their medication burden.

Conclusion
Approximately half of patients with choose a ‘pill-in-the-pocket’ OAC guided by daily rhythm monitoring with an ICM if proven to be safe and effective at reducing thromboembolism.
Single versus dual antiplatelet therapy following transcatheter left atrial appendage closure
Authors: Massalha E , Beinart R , Leshem E , Nof E , Guetta V , Barbash I , Sabbag A 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Left atrial appendage occlusion (LAAO) had emerged as an alternative to anticoagulation in patients with non-valvular atrial fibrillation and a contraindication to long-term oral anticoagulants (OAC). LAAO implantation aims to reduce the risk of both systemic thromboembolism and the bleeding events associated with prolonged OAC. Post-procedural antithrombotic regimen varies among patients and may include antiaggregant (dual or single agents) or anticoagulation therapy in minority patients. The current study aims to compare the effectiveness and safety of post-procedural antithrombotic treatment with either dual antiplatelet therapy (DAPT) or single antiplatelet therapy (SAPT) in a real-world cohort.

Methods
The cohort consisted of 205 consecutive patients who had undergone LAAO at Sheba medical center between the years 2010-2020. We prospectively evaluated baseline characteristics and periprocedural clinical, laboratory, and imaging data. All patients were followed by scheduled in-clinic visits. After excluding patients prescribed OAC following the procedure or deceased in the index procedure, the study cohort was divided into two groups according to the antithrombotic regimen following the LAAO: SAPT (35 patients) versus DAPT (151 patients). A propensity analysis via the stabilized inverse-probability-of-treatment weighting (IPTW) was applied.

Results
The leading etiologies for transcatheter LAAO were previous gastrointestinal bleeding (41%) and previous intracranial bleeding (32%). The median CHADSVASC score is 5 [IQR:4-6]. Patients discharged with SAPT following LAAO were older (78±8 yrs vs.75±8 yrs), accompanied by an evident trend over the years of discharging more patients with SAPT instead of DAPT (Figure 1). No statistically significant differences were observed in other baseline characteristics, including gender, hypertension, diabetes mellitus, malignancy, chronic renal or heart failure. During two years of clinical follow-up, no differences in major adverse cardiovascular events were observed between the two groups (20% vs.19% for SAPT and DAPT, respectively). After applying an IPTW propensity analysis adjusting for several clinical and procedural relevant parameters, a K-M survival curve demonstrates no survival benefits of dual over single antiplatelet therapy (Figure 2).

Conclusions
Among patients undergoing LAAO, post-procedural DAPT provides no survival benefits over single antiplatelet therapy.