bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of continuity index for drag versus point-by-point ablation with the use of proactive esophageal cooling
Authors: Sherman J , Putzel N , Lazarus C , Zagrodzky W , Sharkoski T , Ro A , Nazari J , Fisher W , Kulstad E , Metzl M 
Published: October 2024

Abstract

Background
Proactive esophageal cooling was recently FDA cleared to reduce the likelihood of esophageal injury during radiofrequency (RF) ablation for treatment of atrial fibrillation (AF). Long-term follow-up data have also shown improved freedom from arrhythmia with proactive esophageal cooling compared to luminal esophageal temperature (LET) monitoring during pulmonary vein isolation (PVI). One hypothesized mechanism is the greater lesion continuity attainable with the use of cooling, which can be quantified by the Continuity Index (which increases as continuity decreases). Increasing the Continuity Index increases gap formation, reduces isolation, and leads to greater AF recurrence; however, the difference in Continuity Index between ablating in a point-by-point fashion versus a dragging fashion has not previously been analyzed.

Purpose
To prospectively measure the Continuity Index of PVI cases and compare the dragging technique to point-by-point technique when using proactive esophageal cooling or LET monitoring.

Methods
We determined the Continuity Index for 101 patients: 77 prospectively utilizing proactive esophageal cooling, 24 retrospectively recorded using LET monitoring. Cases were completed by four operators, three utilizing point-by-point technique, and one using the drag technique. The Continuity Index was calculated by incrementing one unit for each lesion that did not border the previous lesion during the PVI (simplifying the original description of the Continuity Index).

Results
For cases using esophageal cooling and performing RF ablation using the drag technique, the average Continuity Index was 8.5 (range: 1 to 14). For point-by-point operators using esophageal cooling, the average Continuity Index was 1.2 (range: 0 to 9), representing a difference of 7.3 between the dragging technique and point-by-point ablation (p &lt; .001). Patients receiving LET monitoring and RF ablation using the drag technique had Continuity Indices of 23.8 (range 15 to 30). Patients receiving LET monitoring and RF ablation using point-by-point ablation had Continuity Indices of 28.4 (range 16 to 50). Figure 1 compares these findings. Only 4 patients (5%) in the esophageal cooling group had a Continuity Index above 6 on either side (all in the dragging group), versus 100% (24) of patients in the LET monitoring group.

Conclusion
Proactive esophageal cooling during PVI is associated with a high degree of lesion continuity, as represented by the low Continuity Index. The drag technique resulted in a higher index than the point-by-point technique, but both provided significantly lower Continuity Indices (greater lesion continuity) than cases using LET monitoring. This may offer a mechanism for the greater freedom from arrhythmia seen to date with proactive cooling in long-term follow-up.Figure 1.Comparison of Continuity Index
The triglyceride-glucose index is a marker of thromboembolic events in atrial fibrillation patient under oral anticoagulation therapy
Authors: Rivera-Caravaca J M , Soler-Espejo E , Gonzalez-Lozano E , Lip G Y H , Marin F , Roldan V 
Published: October 2024

Abstract

Background
Atrial fibrillation (AF) increases the risk of stroke and thromboembolism; and appropriate risk stratification is central for better targeted patient management. The triglyceride-glucose (TyG) index indirectly assesses insulin resistance, and has been associated with cardiovascular risk.

Purpose
To investigate whether the TyG index could be a biomarker for assessing the risk of thromboembolic events in patients with AF.

Methods
We performed an observational prospective cohort study including outpatients diagnosed with AF starting vitamin K antagonist (VKA) or direct-acting oral anticoagulants (DOAC) therapy from January, 2016 to November, 2021. The primary endpoint was a combination of thromboembolic events, considered as the composite of myocardial infarction, and/or venous thromboembolism, and/or ischemic stroke/transient ischemic attack, over 2 years of follow-up.
The TyG index was calculated as the natural logarithm (Ln) of the product of baseline plasma glucose and triglyceride using the following formula: Ln [fasting triglycerides (mg/dL) × fasting glucose (mg/dL)]/2. Patients were stratified into tertiles according to their TyG index (ie. first tertile: TyG index &lt;4.59; second tertile: TyG index 4.59-4.83; third tertile: TyG index &gt;4.83).

Results
We included 2907 patients (median age 77 [70-83] years; 52.5% female). The median TyG index was 4.71 (4.53-4.91), and 34% (989) where in the third tertile of TyG index. During a follow-up of 2 years, 209 (7.2%) patients suffered a thromboembolic event.
Compared to patients in the first or second tertiles of TyG index, patients in the third tertile had an increased annual event rate of thromboembolic events (3.40 per 100 patient-years vs. 4.76 per 100 patient-years, p=0.043; and 3.41 per 100 patient-years vs. 4.76 per 100 patient-years, p=0.044), and higher incidence rate ratio (1.41 [95% CI 1.01-1.98], p=0.044 vs. first tertile; 1.40 [95% CI 1.01-1.97], p=0.044 vs. second tertile).
Cox regression analyses adjusted for several risk factors demonstrated that the TyG index was an independent predictor for thromboembolic events (aHR 1.82; 95% CI 1.15-2.89; p=0.011). Patients in the third tertile of TyG index presented a 64% higher risk of thromboembolic events (aHR 1.64; 95% CI 1.17-2.29; p=0.004) (Table), with significantly lower event free survival (log-rank test p-value = 0.016) (Figure).

Conclusions
In this real-world cohort of AF patients under oral anticoagulation therapy, elevated TyG index was an independent risk factor for thromboembolic events. The TyG index is a simple, low-cost indicator, that could be used as a screening tool in everyday clinical practice.
Dynamic recommendation for anticoagulant treatment in patients with atrial fibrillation using deep reinforcement learning method
Authors: Li S , He L , Li M , Yang Z , Wang J , Xu Z , Jiang C , Sang C , Du X , Dong J , Ma C 
Published: October 2024

Abstract

Background
Recent evidence suggests that the guideline-directed anticoagulant therapy for atrial fibrillation (AF) remains controversial. Widely-used CHA2DS2-VASc score is solely based on limited traditional cardiovascular risk factors, omitting AF characteristics and other markers of thromboembolic risk. A more efficient, safer and more personalized anticoagulant approach is warranted.

Purpose
To develop a data-driven deep reinforcement learning (DRL) model for guiding dynamic anticoagulant treatment in AF patients to improve cardiovascular outcomes.

Methods
Participants of this study were enrolled from the multicentred China Atrial Fibrillation (China-AF) Registry between August 2011 and December 2022, who were with regular follow-up every 6 months. We excluded patients on warfarin at baseline due to its declining usage trend in non-valvular AF patients in China. The DRL model was trained in 70% randomly selected patients for optimal dynamic decision-making, and then subsequently tested in the remaining 30%. Data of sociodemographic characteristics, AF characteristics, medical history, lifestyle factors, laboratory examination, and medications were input for model training. Concordance rate between DRL model’s recommendations and physicians’ actual decisions of non-vitamin-K-antagonist oral anticoagulant (NOAC) prescription among all visits before censoring was calculated for each patient. Primary outcome was the composite of cardiovascular death, ischemic stroke, transient ischemic attack or systemic embolism (SSE), and major bleeding. Shapley additive explanation analysis ranked the most important factors affecting decision-making of the DRL model.

Results
A total of 20068 patients (mean age: 63.0±12.0 years; 36.2% female) were randomly divided into a training cohort of 14050 patients and a testing cohort of 6018 patients. The model’s NOAC recommendations were mostly affected by age, prior NOAC prescription, body mass index, hypertension history and prior statin prescription (Figure 1). Patients with concordance rates of 50.1%-75% and 75.1%-100% had significant risk reductions for the primary outcome (adjusted HR =0.63; 95% CI, 0.46-0.85; P = 0.003 and adjusted HR =0.59; 95% CI, 0.46-0.75; P &lt;0.001, respectively), compared to those with a concordance rate of 0-25%. Similar results were observed for all-cause death, cardiovascular death and SSE outcomes, that patients with the highest concordance rate had a significant lower risk, compared to those with the lowest concordance rate. There was a nonsignificant but similar trend with regard to major bleeding events (Figure 2).

Conclusions
This modelling study suggests that a data-driven DRL model might provide more efficient, safer and more personalized anticoagulant suggestions, potentially assisting physicians in clinical practice.
Risk of thromboembolic and haemorrhagic events associated with anticoagulation among 11,355 patients with non-valvular atrial fibrillation and thrombocytopenia
Authors: Tam M , Sun W , Lai A , Yan B P 
Published: October 2024

Abstract

Background
Oral anticoagulation (OAC) is the mainstay for stroke prophylaxis in patients with non-valvular atrial fibrillation (NVAF). Management is challenging among patients with NVAF complicated with thrombocytopenia.

Purpose
We compared risk of thromboembolic and hemorrhagic events between vitamin-k antagonist (VKA) and direct oral anticoagulants (DOAC) users.

Methods
We retrospectively analyzed patients with thrombocytopenia and NVAF prescribed VKA (N=5,251, 46.2%) and DOAC (N=6,104, 53.8%) between January 2012 and July 2022 in 16 public hospitals in Hong Kong. Mild to moderate thrombocytopenia was defined as mean platelet count (PLT) 100-150 × 10^9/L and 50-100 × 10^9/L respectively, during the year of OAC initiation. Propensity-matched cohorts of VKA and DOAC were generated on the basis of age, sex, baseline co-morbidities (components of CHA2DS2VASC and HAS-BLED scores) and medications. Time to intracranial hemorrhage (ICH), gastrointestinal bleeding (GIB) and ischemic stroke (IS) was analyzed using competing risk regression, accounting for death as competing risk. Subgroup analysis was performed to detect heterogeneity of effect across mild and moderate thrombocytopenia. Secondary outcome included (i) comparisons between 4 DOAC agents with full dose; (ii) Full-dose DOAC vs. reduced-dose DOAC.

Results
Of the whole cohort (N=11,355, mean age 75.8±10.5, female 38.6%), 10.3% (n=1,174) and 89.7% (n=10,181) had moderate and mild thrombocytopenia, respectively. After propensity-score matching, VKA and DOAC (n=4,302 each cohort) users were well balanced at baseline characteristics, with a median follow-up of 4.0 (IQR: 1.6-7.3) years. Overall, utilization of DOAC was associated with reduced risk of ICH [Hazards Ratio (HR) 0.56 (95% CI 0.45-0.70)] and GIB [HR 0.60 (95% CI 0.48-0.75)], compared with VKA. No difference in risk of IS was observed [HR 1.00 (95%CI 0.83-1.20)]. Dosing reduction of DOAC made no difference in all outcomes. Subgroup analysis demonstrated the benefit in decreasing GIB might be more marked in moderate thrombocytopenia [(HR 0.24 (95%CI 0.09-0.61)], than in mild thrombocytopenia [HR 0.64 (95%CI 0.51-0.81)].

Conclusion
In patients with NVAF and thrombocytopenia, DOAC has similar efficacy but better safety profile than VKA. In terms of GIB, the superiority appeared to be more pronounced in patients with more significant thrombocytopenia.
Clinical outcomes in &gt;10,000 Asian vs &gt;61,000 Non-Asian race patients with AF randomized to Warfarin vs DOACs: a patient-level meta-analyses from COMBINE AF
Authors: Chao T , Braunwald E , Palazzolo M G , Antman E M , Carnicelli A P , Connolly S J , Eikelboom J , Granger C B , Patel M R , Ruff C T , Wallentin L , Giugliano R P 
Published: October 2024

Abstract

Background
Randomized data comparing clinical outcomes of atrial fibrillation (AF) patients with Asian vs non-Asian races are limited.

Methods
Using the COMBINE AF (A Collaboration Between Multiple Institutions to Better Investigate Non-Vitamin K Antagonist Oral Anticoagulant Use in Atrial Fibrillation) database (data from RE-LY, ROCKET AF, ARISTOTLE, and ENGAGE AF-TIMI 48), we performed an individual patient-level meta-analysis to investigate and compare clinical outcomes of AF patients with self-defined Asian and non-Asian races adjusted for baseline characteristics. Standard-dose direct oral anticoagulants (SD DOAC) were defined as dabigatran 150mg bid; rivaroxaban 20mg (15mg) QD, apixaban 5 mg (2.5 mg) bid, or edoxaban 60 mg (30 mg) QD. Low-dose DOACs (DOACs [LD]) were defined as dabigatran 110 mg bid or edoxaban 30 mg (15mg) QD.

Results
There were 10,212 pts of Asian race and 61,471 non-Asian races in the COMBINE AF database. Compared with non-Asians, Asians were on average 3.2 yrs younger, 20 kg lighter, had worse renal function (mean CrCl 64.9 vs. 77.3 mL/min), and higher rates of prior stroke/transient ischemic attack (37.2% vs 26.6%), P&lt;0.001 for each. The median value of time in therapeutic range of patients randomized to warfarin was lower in Asians than non-Asians (57.7% vs. 66.2%, P&lt;0.001). In the warfarin arm, Asians had a higher adjusted risk of stroke/systemic embolic events (SEE), major bleeding (MB), ICH, GI bleeding (GIB), and net clinical outcome (NCO: stroke/SEE, MB, or death)(Figure; Upper panel). Compared to warfarin, SD DOACs significantly reduced the risks of stroke/SEE, MB, and NCO to a greater degree in Asians than non-Asians (HR stroke/SEE: Asians 0.65 vs Non-Asians 0.86; HR MB: Asians 0.62 vs Non-Asians 0.91; HR NCO: Asians 0.76 vs non-Asians 0.94; Pint &lt;0.02 for each), while SD DOACs increased GIB only in non-Asians (Asian HR 0.92 [0.69-1.23] vs Non-Asians HR 1.41 [1.25-1.58], Pint 0.009; Figure Lower panel).

Conclusions
The adjusted risks of stroke/SEE and major bleeding with warfarin were higher in Asians compared to non-Asians. The benefits of DOACs over warfarin in preventing stroke/SEE, MB, and net clinical outcomes were significantly greater in Asians than non-Asians.
Predictors and outcomes of intracranial hemorrhage in 58,000 patients with atrial fibrillation on oral anticoagulation: insights from COMBINE-AF
Authors: Tannu M , Hua K , Hankey G , Alexander J H , Giugliano R P , Eikelboom J , Lopes R , Wallentin L , Ruff C , Oldgren J , Patel M , Jones W S , Mahaffey K W , Carnicelli A , Granger C B 
Published: October 2024

Abstract

Background
Among anticoagulated patients with atrial fibrillation (AF), intracranial hemorrhage (ICH) is the leading cause of bleeding-related death and disability. The COMBINE-AF database has patient-level data from four major randomized-controlled trials [ROCKET-AF (rivaroxaban), RE-LY (dabigatran), ENGAGE-TIMI 48 (edoxaban), ARISTOTLE (apixaban)] of direct oral anticoagulants (DOACs) versus warfarin in patients with AF.

Purpose/Methods
We investigated the rates, predictors, and mortality of ICH in patients randomized to DOAC (rivaroxaban, dabigatran, edoxaban, apixaban) or warfarin. ICH was subclassified as subdural or non-subdural (intracerebral, intraventricular, subarachnoid, epidural). Multivariable Cox models were used to identify predictors of ICH. Frequencies and fatality rates of ICH were calculated and displayed as Kaplan-Meier curves.

Results
In COMBINE-AF, there were 58,634 patients randomized to either DOAC (n=29,362) or warfarin (n=29,272). The mean age was 70.5 years, 37% were female, and 81% were White. The mean CHA2DS2-VASc score was 2.6, 43% of patients had a history of smoking, 31% had diabetes, and 29% had prior stroke/TIA.
After a mean of 32 months, ICH occurred in 593 patients (1.01%, 0.58 per 100-patient years, 95% CI [0.54, 0.63]). The most significant independent predictors of ICH in order of importance were: treatment with warfarin, older age, prior stroke/TIA, enrollment in Asia, antiplatelet use at randomization, and history/risk of falls (Figure 1).
Mortality after ICH was 48.4% (287/593 participants), with a majority of deaths (82%) occurring within 30 days of ICH event. Non-subdural ICH was more common than subdural ICH (73% vs 25%) and had a higher risk of death (Figure 2). Participants randomized to DOAC had a lower risk of both subdural and non-subdural ICH than those treated with warfarin; however, mortality rates after ICH were similar regardless of anticoagulant type.

Conclusion
ICH is an uncommon but devastating complication of oral anticoagulation in patients with atrial fibrillation. The mortality rate following ICH is high, particularly following non-subdural ICH. To reduce the risk of ICH, clinicians should consider using DOACs over warfarin and carefully evaluate the need for antiplatelet therapy, particularly in patients with other significant predictors of ICH such as prior stroke, advanced age, residence in Asia, and history of falls.Predictors of Intracranial Hemorrhage90-Day Mortality after ICH
Combined PVI and LAAC is feasible using RFA or PFA in a canine model despite acute tissue edema in PFA versus RFA
Authors: Saliba W , Delurgio D , Mikaelian B , Jaber W , Baldo C , Kilvington J , Curtis M A , Shuros A , Hynes E , Natale A 
Published: October 2024

Abstract

Background
Combined procedure with pulmonary vein isolation (PVI) using thermal energy followed by left atrial appendage closure (LAAC) has been used in select patient populations with positive results. Pulsed field ablation (PFA) is a novel non-thermal ablation modality that ablates cardiac tissue by irreversible electroporation. The effect of PFA on cardiac tissue and its interaction with a LAAC device in a single procedure has not been studied.

Purpose
To evaluate using transesophageal echo (TEE) imaging the acute tissue response following ablation by PFA compared to radiofrequency ablation (RFA) and its interaction with the WATCHMAN FLX Pro LAAC device when used in a combined procedure in a healthy canine model.

Methods
Nine mongrel canines underwent PVI using either circumferential PFA (FARAPULSE) energy application (n=6) or RFA energy (n=3). TEE imaging was obtained at the time of the procedure before and immediately after ablation energy application. The general appearance and echogenicity of the left lateral ridge was assessed and the os of the left atrial appendage (LAA) was measured in the four standard TEE views (0, 45, 90, and 135 degrees). Decisions about device sizing were made accordingly. PVI was evaluated by entry and exit block in all veins except the right inferior pulmonary vein (RIPV), which was not ablated. Following ablation, the LAAC device was implanted using TEE and fluoroscopic guidance in all animals and the percentage of compression measured. PASS criteria were assessed before the release of each device. All animals received dual antiplatelet therapy post implant.

Results
PVI was confirmed in all animals (except RIPV which was not targeted for ablation) using PFA and RFA. LAA dimensions (at device landing site) did not change substantially after RF ablation. With PFA, there was evidence of more diffuse edema and decrease in LAA diameter (Table). The LAAC device was implanted successfully after meeting PASS criteria in all animals within 30 minutes post ablation. The device size was decreased following PFA in two (2/6) animals, whereas there was no deviation from baseline measurements in device size for any of the RFA animals. Average LAAC device compression was higher for PFA versus RFA animals (Table). TEE post implant confirmed absence of any peri-device leaks in all animals.

Conclusion
Concomitant PVI using PFA (FARAPULSE) and LAAC (WATCHMAN FLX Pro) is feasible with 100% success and no residual acute peri-device leak. In the canine model, PFA is associated with more diffuse edema compared to RFA, which might affect device sizing. Long term consequences of this acute edema need to be evaluated in serial imaging and future larger clinical trials.Table
Diagnostic yield of actionable arrhythmias in patients referred with syncope and collapse using ePatch extended holter
Authors: Dunn A , Parikh P , Gillstrom G , Wadhwa M 
Published: October 2024

Abstract

Background/Introduction
Cardiac syncope commonly points to a potentially lethal disease process and carries one-year mortality up to 30%. Current guidelines on management of syncope suggest choosing ambulatory monitoring modality based upon the likelihood of symptoms during the monitoring period and is frequently undertaken with short duration (0-2 days) or extended wear Holter (EWH) monitoring (3-14 days).

Purpose
Determine the diagnostic yield (DY) of actionable arrhythmias (AA) in patients referred for syncope and collapse prescribed short or extended ambulatory monitoring.

Methods
A retrospective analysis was conducted for patients wearing the Philips ePatch between July 1st, 2022, and June 30th, 2023, with ICD-10 referral code R55 (Syncope and Collapse). Monitoring duration was grouped by 0-2, 3-7, and 8-14 days of wear time. Wear time was defined as number of hours with analysable ECG data. Arrhythmia detection was defined as either non-AA (did not meet urgent or emergent criteria) or AA (met urgent and/or emergent criteria). Urgent criteria were defined as Atrial Fibrillation/Flutter (&gt;10 seconds), Ventricular Tachycardia (&gt;100 BPM for &gt;3 beats), Severe Tachycardia (&gt;170 BPM for ≥30 seconds), Pause/Asystole (≥3 seconds), Severe Bradycardia (&lt;35 BPM), and 2nd Degree or Higher AV Block. Emergent criteria were defined as VT (&gt;100 BPM for ≥30 beats), Severe Tachycardia (≥220 BPM for ≥30 seconds), Pause/Asystole (≥10 seconds), and Severe Bradycardia (&lt;20 BPM).

Results
The DY for any urgent and/or emergent AA was 6.8%, 11.0%, and 20.4% at 0-2, 3-7 and 8-14 days of wear time, respectively (p&lt;0.00001 for all). For urgent AA, DY increased 1.6X at 3-7 vs 0-2 days, 1.9X at 8-14 vs 3-7 days and 3X at 8-14 vs 0-2 days of wear time (p&lt;0.05 for all); for emergent AA, the DY increased 5X at 3-7 vs 0-2 days, 1.6X at 8-14 vs 3-7 days, and 8.2X at 8-14 vs 0-2 days of wear time (p&lt;0.05 for all) (Graph 1). When examining tachyarrhythmias vs bradyarrhythmias, similar multiplicative yields in AA were noted between short, intermediate, and extended duration monitoring; statistical significance was noted for all arrhythmia subtypes (p&lt;0.01), except for Severe Tachycardia and Bradycardia which were not significant between 0-2 and 3-7 days of wear time (Graph 2).

Conclusion(s)
In patients referred for ambulatory monitoring with syncope and collapse, urgent and emergent actionable arrhythmias increase significantly when extending from short to intermediate to long duration monitoring, with both tachyarrhythmias and bradyarrhythmias demonstrating similar increases in occurrence. Accordingly, EWH monitoring in patients referred with syncope and collapse has greater potential to identify arrhythmic aetiologies than use of standard duration Holter.