Dwell Time Research Articles

HDR brachytherapy afterloader quality assurance optimization using monolithic silicon strip detectors.

There currently exists no widespread high dose-rate (HDR) brachytherapy afterloader quality assurance (QA) tool for simultaneously assessing the afterloader's positional, temporal, transit velocity and air kerma strength accuracy. The purpose of this study was to develop a precise and rigorous technique for performing daily QA of HDR brachytherapy afterloaders, incorporating QA of: dwell position accuracy, dwell time accuracy, transit velocity consistency and relative air kerma strength (AKS) of an Ir-192 source. A Sharp ProGuide 240mm catheter (Elekta Brachytherapy, Veenendaal, The Netherlands) was fixed 5mm above a 256 channel epitaxial diode array 'dose magnifying glass' (DMG256) (Centre for Medical and Radiation Physics, University of Wollongong). Three dwell positions, each of 5.0s dwell times, were spaced 13.0mm apart along the array with the Flexitron HDR afterloader (Elekta Brachytherapy, Veenendaal, The Netherlands). The DMG256 was connected to a data acquisition system (DAQ) and a computer via USB2.0 link for live readout and post-processing. The outputted data files were analyzed using a Python script to provide positional and temporal localization of the Ir-192 source by tracking the centroid of the detected response. Measurements were repeated on a weekly basis, for a period of 5weeks to determine the consistency of the measured parameters over an extended period. Using the DMG256 for relative AKS measurements resulted in measured values within 0.6%-3.0% of the expected activity over a 7-week period. The sub-millisecond temporal accuracy of the device allowed for measurements of the transit velocity with an average of (10.88±1.01) cm/s for 13mm steps. The dwell position localization for 1, 2, 3, 5, and 10mm steps had an accuracy between 0.1 and 0.3mm (3σ), with a fixed temporal accuracy of 10ms. The DMG256 silicon strip detector allows for clinics to perform rigorous daily QA of HDR afterloader dwell position and dwell time accuracy with greater precision than the current standard methodology using closed circuit television and a stopwatch. Additionally, DMG256 unlocks the ability to perform measurements of transit velocity/time and relative AKS, which are not possible using current standard techniques.

MAGnetic REtriaval Device for Minimally Invasive Ureter Stent Removal.

Purpose: To assess the effectiveness and pain intensity associated with magnetic ureteral stent removal using a retriever, without the aid of ultrasound guidance. Methods: We prospectively enrolled 100 patients who underwent retrograde rigid and flexible ureterorenoscopy with or without laser lithotripsy for ureteronephrolithiasis treatment from September 2021 to June 2023. These patients were assigned in two groups. Group 1 underwent the traditional ureteral stent insertion, while Group 2 underwent magnetic ureteral stent insertion. Both insertion and removal times were documented. The indwelling time for ureteral stents was 14 days. One group underwent stent removal via flexible cystoscopy using grasping forceps and the other group using just a magnetic retriever, without the aid of ultrasound guidance. The numeric pain rating scale, recommendation rate, and a standardized self-answered ureter stent symptoms questionnaire (USSQ) were obtained directly after stent removal. Results: Both groups presented comparable characteristics in factors such as age, body mass index, history of stone treatments, procedure type, and complication rates during and post-surgery. Time taken for ureteral stent insertion did not differ significantly between the groups (131.2 seconds for Group 1 vs 159.1 seconds for Group 2). However, the stent removal time (152.1 seconds for Group 1 vs 35.4 seconds for Group 2) and pain intensity (6 for Group 1 vs 2 for Group 2) were significantly lower for Group 2. Furthermore, five out of the six sections of the USSQ showed significantly better results for Group 2. Conclusions: The use of magnetic ureteral stents, as a safe and efficient alternative to conventional ureteral stents, not only eliminates the need for cystoscopy but also conserves resources and reduces patient discomfort.

Practical exponential stability and applications of switched homogeneous nonlinear systems with external inputs and impulses

The practical exponential stability of switched homogeneous nonlinear systems (SHNS) with external inputs and impulses is studied in this paper, which includes two types of continuous-time systems and discrete-time systems. Specifically, we add a kind of nonnegative impulses which is consistent with the switching behaviours for the systems. We first study switched homogeneous positive nonlinear systems (SHPNS) case, then we extend the SHPNS to a time-varying SHNS case. The primary difficulty of this research is the estimation of Lyapunov function value at switching-impulse points under the coupling effects of synchronous switches and state jumps. By employing the max-separable Lyapunov function approach, we present new sufficient stability criteria and design new switching-impulse signals, and successfully establish the new relation between the average dwell time parameter and impulse strength. Then, we apply the obtained results to the time-varying vehicle formation model with impulses. At last, four examples are given to demonstrate the feasibility of our results, which includes the specific algorithm verification process.

Data-driven machine learning approach for predicting dwell fatigue life in two classes of Titanium alloys

Predicting dwell fatigue life accurately in Titanium (Ti) alloys is vital for designing reliable components such as aero-engine discs and blades. This study proposes a data-driven machine learning (ML) approach for precisely predicting dwell fatigue life in two classes of Ti alloys: near α and α + β alloys. To build a robust model, the data-driven approach tackles this multi-dimensional problem by training a comprehensive dataset of various input features, including alloy composition, monotonic properties, and fatigue testing parameters. Advanced ensemble-based algorithms, Gradient Boosting (GBOOST) and Extreme Gradient Boosting (XGBOOST) are employed. The split-insensitive best-performing XGBOOST model achieved a high accuracy (R2) score of 89.9 %, indicating impressive prediction capability. The model’s robustness is further assessed using an unseen validation dataset to draw qualitative and quantitative conclusions. ML model’s validation further involved comparing its predictions with actual experimental trends across relationships, such as dwell life versus dwell time and dwell-debit versus dwell time. Dwell-debit is also predicted as a function of varying stresses normalized to 0.2 % yield strength, highlighting the susceptibility of investigated Ti alloys to dwell fatigue. Additionally, the SHapley Additive exPlanations (SHAP) analysis was conducted to gain deeper insights into various input features affecting dwell fatigue life.

A comprehensive pre-clinical treatment quality assurance program using unique spot patterns for proton pencil beam scanning FLASH radiotherapy.

Quality assurance (QA) for ultra-high dose rate (UHDR) irradiation is a crucial aspect in the emerging field of FLASH radiotherapy (FLASH-RT). This innovative treatment approach delivers radiation at UHDR, demanding careful adoption of QA protocols and procedures. A comprehensive understanding of beam properties and dosimetry consistency is vital to ensure the safe and effective delivery of FLASH-RT. To develop a comprehensive pre-treatment QA program for cyclotron-based proton pencil beam scanning (PBS) FLASH-RT. Establish appropriate tolerances for QA items based on this study's outcomes and TG-224 recommendations. A 250 MeV proton spot pattern was designed and implemented using UHDR with a 215nA nozzle beam current. The QA pattern that covers a central uniform field area, various spot spacings, spot delivery modes and scanning directions, and enabling the assessment of absolute, relative and temporal dosimetry QA parameters. A strip ionization chamber array (SICA) and an Advanced Markus chamber were utilized in conjunction with a 2cm polyethylene slab and a range (R80) verification wedge. The data have been monitored for over 3 months. The relative dosimetries were compliant with TG-224. The variations of temporal dosimetry for scanning speed, spot dwell time, and spot transition time were within±1mm/ms,±0.2 ms, and±0.2 ms, respectively. While the beam-to-beam absolute output on the same day reached up to 2.14%, the day-to-day variation was as high as 9.69%. High correlation between the absolute dose and dose rate fluctuations were identified. The dose rate of the central 5×5 cm2 field exhibited variations within 5% of the baseline value (155Gy/s) during an experimental session. A comprehensive QA program for FLASH-RT was developed and effectively assesses the performance of a UHDR delivery system. Establishing tolerances to unify standards and offering direction for future advancements in the evolving FLASH-RT field.

Investigation on spray combustion modeling for performance analysis of future low- and zero-carbon DI engine

Global warming issues and fossil fuel depletion crisis have forced transportation industry to seek clean engine fuels both liquid and gaseous. Dual-fuel mode with high-pressure direct injection (HPDI) has been recognized as mainstream method in developing flexible-fuel internal combustion engines (ICEs). But flexible-fuels’ physicochemical properties and spray combustion characteristics under HPDI have changed a lot. Unfortunately, there is currently no universal model for predicting spray combustion behaviors and analyzing performance of flexible-fuel ICEs. Therefore, this paper aims to develop a novel spray combustion model and provide optimal injection and combustion strategies for performance improvement of low- and zero-carbon HPDI ICEs. Based on balance of momentum change and vortex ring drag force, the jet spray effective injection velocity is obtained. Then the jet spray penetration under varying injection rate is solved. Finally, the developed model is established and validated experimentally, with the spray combustion characteristics of various fuels investigated. The results show that the developed model has a good accuracy and robustness for flexible-fuels’ characteristic analysis. Meanwhile, multiple-injection could increase the combustion efficiency (CE) over 10.27 % than single-injection, and CE increases with dwell time. Moreover, CE of H2 in nitrogen-oxygen (N2–O2) atmosphere is 10.15 % higher than that in argon-oxygen (Ar–O2) atmosphere.

Adaptive Fuzzy Optimal Control for Interconnected Switched Nonlinear Systems With Dwell Time

Adaptive Fuzzy Optimal Control for Interconnected Switched Nonlinear Systems With Dwell Time

Effect of multi-cancer early detection screening on late-stage cancers: A modeling study.

11076 Background: Emerging blood-based multi-cancer early detection (MCED) tests can revolutionize early cancer detection. We evaluated the potential impact of MCED screening in reducing risk of late-stage diagnosis of 12 specific cancers which represent 70% of all cancer incidence in the US. Methods: We developed Simulation Model for MCED (SiMCED), a microsimulation model of 12 solid tumor cancer types: breast, colorectal, endometrial, esophageal, gastric, kidney, liver, lung, ovarian, pancreatic, prostate, and urinary bladder. Transitions between cancer stages (I-IV) were driven by cancer type- and stage-specific dwell times, which were synthesized from published literature and empirical estimates. MCED test sensitivity was derived from the PRE-ASCEND study on average-risk American adults. The model was calibrated to reproduce yearly observed cancer incidence diagnosed symptomatically or through screening as captured in the Surveillance, Epidemiology, and End Results (SEER) database, while accounting for unobserved cancer incidence by age, sex, and cancer type and stage. Using a 50-year time horizon, we simulated 100,000 individuals aged 50 to 84 years. Diagnosis of cancer could arise from usual care (UC) or annual MCED screening. Results: Over the 50-year horizon, MCED screening of 100,000 individuals resulted in 1,323 fewer Stage IV (24%) diagnoses relative to UC, with 38% of Stage IV reductions attributed to non-screening-detectable cancer types (i.e., those without recommended screening guidelines). The table displays absolute and percentage reductions in Stage IV diagnoses for the 8 cancer types with the highest absolute reduction in Stage IV diagnoses. The percentage of Stage IV reduction was 21% for screening-detectable cancers and 29% for non-screening-detectable cancers. Conclusions: Our study suggests that MCED screening could be effective for reducing the incidence of Stage IV cancer, which is associated with the worst survival and quality of life. Of note, MCED has the potential to reduce Stage IV cancer incidence for cancers without recommended screening guidelines. However, the real-world impact of MCED tests and their cost-effectiveness require further investigation. [Table: see text]

Multi-Source Domain Adaptation Enhanced Warehouse Dwell Time Prediction

Multi-Source Domain Adaptation Enhanced Warehouse Dwell Time Prediction

Abnormal dynamic functional connectivity and topological properties of cerebellar network in male obstructive sleep apnea.

To investigate dynamic functional connectivity (dFC) within the cerebellar-whole brain network and dynamic topological properties of the cerebellar network in obstructive sleep apnea (OSA) patients. Sixty male patients and 60 male healthy controls were included. The sliding window method examined the fluctuations in cerebellum-whole brain dFC and connection strength in OSA. Furthermore, graph theory metrics evaluated the dynamic topological properties of the cerebellar network. Additionally, hidden Markov modeling validated the robustness of the dFC. The correlations between the abovementioned measures and clinical assessments were assessed. Two dynamic network states were characterized. State 2 exhibited a heightened frequency, longer fractional occupancy, and greater mean dwell time in OSA. The cerebellar networks and cerebrocerebellar dFC alterations were mainly located in the default mode network, frontoparietal network, somatomotor network, right cerebellar CrusI/II, and other networks. Global properties indicated aberrant cerebellar topology in OSA. Dynamic properties were correlated with clinical indicators primarily on emotion, cognition, and sleep. Abnormal dFC in male OSA may indicate an imbalance between the integration and segregation of brain networks, concurrent with global topological alterations. Abnormal default mode network interactions with high-order and low-level cognitive networks, disrupting their coordination, may impair the regulation of cognitive, emotional, and sleep functions in OSA.

Asynchronous control of switched Lurie systems with dwell time

Asynchronous control of switched Lurie systems with dwell time

Abnormal brain functional network dynamics in amyotrophic lateral sclerosis patients with depression.

Since depression is common in amyotrophic lateral sclerosis (ALS) patients, we aimed to explore the specific brain functional network dynamics in ALS patients with depression (ALS-D) compared with healthy controls (HCs) and ALS patients without depressive symptoms (ALS-ND). According to the DSM-V, 32 ALS-D patients were selected from a large and newly diagnosed ALS cohort. Then, 32 demographic- and cognitive-matched ALS-ND patients were also selected, and 64 HCs were recruited. These participants underwent resting-state fMRI scans, and functional connectivity state analysis and dynamic graph theory were applied to evaluate brain functional network dynamics. Moreover, the Hamilton Depression Rating Scale (HDRS) was used to quantify depressive symptoms in the ALS-D patients. Four distinct states were identified in the ALS-D patients and controls. Compared with that in HCs, the fraction rate (FR) in state 2 was significantly decreased in ALS-D patients, and the FR in state 4 was significantly increased in ALS-D patients. Compared with that of HCs, the dwell time in state 4 was significantly increased in the ALS-D patients. Moreover, compared with that in the ALS-D patients, the FR in state 3 was significantly decreased in the ALS-ND patients. Among the ALS-D patients, there was the suggestion of a positive association between HDRS scores and dwell time of state 4, but this association did not reach statistical significance (r = 0.354; p = 0.055). Depression is an important feature of ALS patients, and we found a special pattern of brain functional network dynamics in ALS-D patients. Our findings may play an important role in understanding the mechanism underlying depression in ALS patients and help develop therapeutic interventions for depressed ALS patients.

Neural network dose prediction for cervical brachytherapy: Overcoming data scarcity for applicator-specific models.

3D neural network dose predictions are useful for automating brachytherapy (BT) treatment planning for cervical cancer. Cervical BT can be delivered with numerous applicators, which necessitates developing models that generalize to multiple applicator types. The variability and scarcity of data for any given applicator type poses challenges for deep learning. The goal of this work was to compare three methods of neural network training-a single model trained on all applicator data, fine-tuning the combined model to each applicator, and individual (IDV) applicator models-to determine the optimal method for dose prediction. Models were produced for four applicator types-tandem-and-ovoid (T&O), T&O with 1-7 needles (T&ON), tandem-and-ring (T&R) and T&R with 1-4 needles (T&RN). First, the combined model was trained on 859 treatment plans from 266 cervical cancer patients treated from 2010 onwards. The train/validation/test split was 70%/16%/14%, with approximately 49%/10%/19%/22% T&O/T&ON/T&R/T&RN in each dataset. Inputs included four channels for anatomical masks (high-risk clinical target volume [HRCTV], bladder, rectum, and sigmoid), a mask indicating dwell position locations, and applicator channels for each applicator component. Applicator channels were created by mapping the 3D dose for a single dwell position to each dwell position and summing over each applicator component with uniform dwell time weighting. A 3D Cascade U-Net, which consists of two U-Nets in sequence, and mean squared error loss function were used. The combined model was then fine-tuned to produce four applicator-specific models by freezing the first U-Net and encoding layers of the second and resuming training on applicator-specific data. Finally, four IDV models were trained using only data from each applicator type. Performance of these three model types was compared using the following metrics for the test set: mean error (ME, representing model bias) and mean absolute error (MAE) over all dose voxels and ME of clinical metrics (HRCTV D90% and D2cc of bladder, rectum, and sigmoid), averaged over all patients. A positive ME indicates the clinical dose was higher than predicted. 3D global gamma analysis with the prescription dose as reference value was performed. Dice similarity coefficients (DSC) were computed for each isodose volume. Fine-tuned and combined models showed better performance than IDV applicator training. Fine-tuning resulted in modest improvements in about half the metrics, compared to the combined model, while the remainder were mostly unchanged. Fine-tuned MAE=3.98%/2.69%/5.36%/3.80% for T&O/T&R/T&ON/T&RN, and ME over all voxels=-0.08%/-0.89%/-0.59%/1.42%. ME D2cc were bladder=-0.77%/1.00%/-0.66%/-1.53%, rectum=1.11%/-0.22%/-0.29%/-3.37%, sigmoid=-0.47%/-0.06%/-2.37%/-1.40%, and ME D90=2.6%/-4.4%/4.8%/0.0%. Gamma pass rates (3%/3mm) were 86%/91%/83%/89%. Mean DSCs were 0.92%/0.92%/0.88%/0.91% for isodoses ≤150% of prescription. 3D BT dose was accurately predicted for all applicator types, as indicated by the low MAE and MEs, high gamma scores and high DSCs. Training on all treatment data overcomes challenges with data scarcity in each applicator type, resulting in superior performance than can be achieved by training on IDV applicators alone. This could presumably be explained by the fact that the larger, more diverse dataset allows the neural network to learn underlying trends and characteristics in dose that are common to all treatment applicators. Accurate, applicator-specific dose predictions could enable automated, knowledge-based planning for any cervical brachytherapy treatment.

Efficacy and safety of pulsed field ablation for accessory pathways: a pilot study.

Radiofrequency ablation (RFA) is used as a first-line therapy for accessory pathways (APs). However, data regarding the effects of pulsed field ablation (PFA) on APs are limited. We sought to evaluate the acute procedural and 6-month success and safety of PFA in a cohort of patients with APs. A focal contact-force sensing PFA catheter was used for patients with APs. PFA generator generated a bipolar and biphasic waveform (± 1000 V) with a duration of 100 ms from the tip of PFA catheter. 100% acute procedural success was achieved in 10 conscious patients with APs (7 left anterolateral, 2 left inferolateral, and 1 right posteroseptal APs) including 6 (60%) patients after an initial application. The average total ablation time was 6.3 ± 4.9 seconds for 4.7 ± 1.8 ablation sites (ASs), including 3.1 ± 2.4 seconds at targets and 3.2 ± 2.9 seconds at 3.2 ± 2 bolus ASs. The mean skin-to-skin time was 59.3 ± 15.5 minutes, and PFA catheter dwell time was 29.4 ± 7.8 minutes. One patient encountered transient sinus arrest during PFA due to parasympathetic overexcitation. Sinus rhythm was restored in all patients without any significant adverse events during short-term follow-up. PFA of APs was feasible, effective, and safe. Its efficiency was remarkable for its ultrarapid termination of AP conduction. Further studies are warranted to prove whether utilization of PFA with current parameters can extend to manifold APs ablation.

Greening container terminals: An innovative and cost-effective solution for sustainable reefer container storage

This research addresses the critical necessity for energy-efficient solutions in port operations. The primary objective of this paper is to introduce and assess the viability of an innovative infrastructure termed Underground Reefer Container Storage (URCS) devised to mitigate the significant and increasing energy demand posed by reefer containers in ports. This study employs a discrete-event simulation (DES) model to evaluate the feasibility, environmental implications, and cost-effectiveness of three distinctive URCS infrastructure designs. These designs are compared against conventional storage methods to ascertain their capacity for minimizing energy usage and greenhouse gas emissions. The analysis reveals that the best scenario for a specific case study involves a multi-block layout comprising two underground yards, capable of accommodating 39% of the overall refrigerated container capacity at a port. This layout cuts CO2 emissions by 61% from the 2.704 GWh/year energy used by refrigerated containers, yielding around 1.4 million USD/year cost savings. Further analyses using weighted searches to prioritize URCS container slotting led to shorter container dwell times at ports, rendering energy savings 23% higher than in similar unplanned settings. Moreover, this study presents URCS as an eco-friendly alternative for port-based reefer container storage, offering practical alignment with sustainability goals and regulations. The innovative design and its successful application provide holistic insights, paving the way for enhanced port energy management and environmental care. In addition, the implementation of URCS has the potential to reshape port procedures, yielding economic and ecological benefits. This initiative contributes to diminishing the carbon footprint of ports, aligning with global endeavors towards greener and more responsible practices.

One year of atrial fibrillation ablation using pulsed-field pentaspline catheter - learning curves based on a single centre experience

Abstract Introduction Pulsed-field ablation (PFA) represents a novel nonthermal strategy for ablation of atrial fibrillation (AF). As the technology has recently emerged in routine clinical praxis, only limited data on learning curves exist so far. Hereby, we present data from our centre regarding learning curves after the first year of using PFA. Methods The ablation procedure was performed under deep sedation or general anaesthesia in patients with paroxysmal or persistent AF. No 3D mapping system was used, procedures were guided by fluoroscopy and intracardiac echocardiography. For ablation itself, a pantaspline over-the-wire catheter with a steerable sheath was used. The following parameters were analysed over the course of time: procedure time, left atrial (LA) catheter dwelling time, total fluoroscopy time, and complications. Patients who received pulmonary vein isolation (PVI) alone and those with another additive set of lesions (PVI+) were analysed separately. Procedural parameters of the first and the last 20 patients of each group were compared for statistical significance. Results A total number of consecutive 159 patients (mean age 63.20 ± 10.51 years, 69.40 % males) were included in the analysis (PVI N = 73 (45.91 %), PVI+ N = 83 (54.09 %)). Procedures were performed by 3 certified electrophysiology specialists usually in random teams of 2 operators. The mean procedure time was 62.59 ± 23.09 min (PVI 59.64 ± 27.27; PVI+ 65.09 ± 18.64 min, P = 0.15). Over time, there was a non-significant decrease in PVI group (60.30 ± 17.44 vs. 52.75 ± 16.33 min, P = 0.16), but no difference in PVI+ cohort (67.85 ± 13.31 vs. 67.65 ± 28.88 min, P = 0.97). The mean LA catheter dwelling time was 39.84 ± 13.52 min (PVI 35.04 ± 10.20 min; PVI+ 44.33 ± 14.72 min, P <0.001). Non-significant shortening of the LA dwelling time was observed in PVI patients (36.56 ± 8.0 vs. 33.37 ± 9.58 min, P = 0.29). In contrast, the LA dwelling time in the PVI+ group became non-significantly longer (42.93 ± 10.62 vs. 48.56 ± 22.28 min, P = 0.39). The mean fluoroscopy time was 9.28 ± 3.66 min (PVI 8.65 ± 3.04; PVI+ 9.80 ± 4.05 min, P = 0.043). Importantly, fluoroscopy time decreased significantly in both groups over time (PVI: 10.63 ± 3.51 vs. 6.95 ± 2.45 min, P <0.001; PVI+: 12.82 ± 4.99 vs. 9.13 ± 4.16 min, P = 0.017). Regarding complications, we observed one pulmonary oedema requiring orotracheal intubation and mechanical ventilation in the early period. Other complications were related to the femoral puncture site. Conclusion Over the course of time with the new PFA technology, we observed a significant decrease in total fluoroscopy time. However, the change in total procedure and LA dwelling time did not reach statistical significance.

Transvenous lead extraction: the jugular pull-through technique

Abstract Background Transvenous lead extraction (TLE) is vital to the management of cardiac implantable electronic devices (CIEDs). Evolving tools and techniques have contributed to an improvement in procedural safety and efficacy. The jugular access is advantageous in TLE, providing a linear, direct path to the heart for extraction sheaths. However, transfer of a lead with a deployed locking stylet from the subclavian to the jugular carries risk of cardiovascular injury. A novel jugular pull-through technique has been described for safe transfer of the lead and locking stylet from the native site to the jugular access, to facilitate TLE using a powered sheath. Purpose We report our early experience of the novel jugular pull-through technique which transfers a locking stylet and lead unit, from the subclavian to the jugular access for completion of TLE. Method The jugular pull-through technique entailed transfer of the deployed locking stylet with the lead via a long-sheath from the subclavian access to the jugular. In brief: a long wire positioned in the Superior Vena Cava via the jugular is snared and pulled from the subclavian site, permitting a long 8.5-french sheath to be railroaded through the jugular to surface at the subclavian access. The deployed locking stylet was fed through this long sheath to emerge at the jugular access; the sheath, locking stylet and lead were then pulled as a single entity to transfer the locking stylet and lead from the subclavian to the jugular. The rotational dissecting sheath was then advanced over the lead via the jugular in linear fashion to complete the lead extraction. Data for consecutive jugular pull-through procedures performed between 1/7/2022 – 31/12/2022 in our high-volume TLE institute were collected and evaluated for safety and efficacy. Results Three male patients aged 69.8±12.5 years with a left ventricle ejection fraction of 46.7±14.4%, underwent TLE for infection (67%). Of the 7 targeted leads, 4 (57%) were extracted using the jugular pull-through technique, all from the right ventricle (50% ICD) with 128±131.8 months dwell time. Of these 3 cases, 1 suffered diabetes, 1 hypertension, 1 ischaemic cardiomyopathy and 1 hypertrophic obstructive cardiomyopathy. All procedures were performed in the cardiac catheterisation suite under general anaesthesia using a locking stylet, compression coil, Evolution RL (13-french), a Needle’s Eye Snare, a loop snare and a long 8.5-french sheath with its 0.032 guidewire. The jugular pull-through technique facilitated 100% complete procedural success and 100% clinical success in the absence of any complications or procedural mortality; there was no 30-day mortality. Conclusion The jugular-pull-through technique allows safe transfer of a fully deployed locking stylet and lead from the subclavian to the jugular access, to facilitate jugular TLE.The jugular pull-through technique

Pulsed electric field, cryoballoon, and radiofrequency for paroxysmal atrial fibrillation ablation: a propensity score-matched comparison

Abstract Background and Aims Pulmonary vein isolation (PVI) is the most effective rhythm control strategy in paroxysmal atrial fibrillation (AF). Pulsed field ablation (PFA) has emerged as a novel, non-thermal energy source to selectively ablate cardiac tissue. We report the first multicenter experience on PVI via the pentaspline FarapulseTM PFA system versus thermal-based technologies in a propensity score-matched population of paroxysmal AF patients. Methods Propensity score matching was adopted to compare PVI-only ablation outcomes via the FarawaveTM PFA system (Group PFA), cryoballoon ablation (Group CRYO), or focal radiofrequency (Group RF) (PFA:CRYO:RF Ratio=1:2:2). Results Among 1572 (mean age: 62.4±11.3 years; 42.5% females) PAF patients undergoing their first time PVI with either PFA (n=174), CRYO (n=655), or RF (n=743), propensity score matching yielded 174 PFA, 348 CRYO, and 348 RF patients. First-pass isolation was achieved in 98.8% of pulmonary veins (PVs) with PFA, 81.5% with CRYO, and 73.1% with RF (p<0.001). Procedural and dwell times were significantly shorter with PFA. Overall complication rates were 3.4% (n=6) with PFA, 8.6% (n=30) with CRYO, and 5.5% (n=19) with RF (p=0.052). The 1-year Kaplan-Meier estimated freedom from any atrial tachyarrhythmia was 79.3% with PFA, 74.7% with CRYO, and 72.4% with RF (log-rank p-value: 0.24). Among 145 repeat ablation procedures, PV reconnection rate was 19.1% after PFA, 27.5% after CRYO, and 34.8% after RF (p=0.01). Conclusion PFA contributed to significantly shorter procedural times. Follow-up data showed a similar arrhythmia freedom among groups, although a higher rate of PV reconnection was documented in post-CRYO and post-RF redo procedures.RecurrencePVs

First multicenter experience of pulmonary vein and posterior wall isolation via a novel focal 9mm lattice tip catheter in a real-world scenario

Abstract Background Pulsed field ablation (PFA) is an innovative technology recently adopted for the treatment of atrial fibrillation (AF). Preclinical and clinical studies have reported a remarkable safety profile, as a result of its tissue specific effect targeting cardiomyocytes and sparing adjacent tissues. The AfferaTM system is a focal 9-mm lattice tip catheter that has recently received regulatory approval. No data currently exist on the feasibility of this technology for first-time pulmonary vein isolation (PVI) and posterior wall isolation (PWI) in a real-world scenario. Objective To evaluate the safety and efficacy of the focal 9-mm lattice tip catheter Sphere-9 (Affera Inc) in a real-world population undergoing PVI and PWI. Methods Consecutive AF patients undergoing first-time PVI plus PWI with the AfferaTM system in two different centres between August and November 2023 were prospectively included. PFA was always used to ablate the posterior left atrium, whereas anterior applications were performed using either radiofrequency energy (RF/PF strategy) or PFA (PF/PF strategy) based on operator's discretion. Primary efficacy endpoint was acute procedural success (successful PVI with evidence of bidirectional block at the end of the procedure). Primary safety endpoint included major technology-related complications occurring within 7 days post-ablation. Secondary endpoints were first pass isolation, acute reconnection, overall complications, procedural, dwelling, and fluoroscopy time. Results Thirty consecutive patients [mean age: 68±6.8 years; 61.7% males; CHA2DS2-VASc Score 2.0 (1.5 – 3.5)] were included. Among them, 66.7% (n=20) had non-paroxysmal AF. PVI was performed with an RF/PF strategy or PF/PF one in 10 (33.3%) and 20 (66.7%) patients, respectively. Posterior wall isolation (PWI) was performed in 30 (100%) cases. The primary endpoint was achieved in 100% of patients for both PVI and PWI with average procedural time of 95 min (77-120 min), dwelling time of 78 min (55-92 min) and fluoroscopy time of 6 min (5-10.5 min) (Figure 1). No technology-related complications were observed. First-pass isolation occurred in 100% of PVI and PWI, with no acute reconnection for PW and 1 case of right PV reconnection in the RF/PF strategy group. Conclusions AF ablation with the focal 9-mm lattice tip catheter Sphere-9 confirmed high efficacy and safety in PVI + PW in a real-world population.Figure 1

EXPRESS: The effect of anxiety and its interplay with social cues when perceiving aggressive behaviours.

Contextual cues and emotional states carry expectations and biases that are used to attribute meaning to what we see. In addition, emotional states, such as anxiety, shape our visual systems, increasing overall, and particularly threat-related, sensitivity. It remains unclear, however, how anxiety interacts with additional cues when categorizing sensory input. This is especially important in social scenarios where ambiguous gestures are commonplace, thus requiring the integration of cues for a proper interpretation. To this end, we decided to assess how states of anxiety might bias the perception of potentially aggressive social interactions, and how external cues are incorporated in this process. Participants (N = 71) were tasked with signalling the presence of aggression in ambiguous social interactions. Simultaneously, an observer (facial expression) reacted (by showing an emotional expression) to this interaction. Importantly, participants performed this task under safety and threat of shock conditions. Decision measures and eye tracking data were collected. Our results showed that threat of shock did not affect sensitivity nor criterion when detecting aggressive interactions. The same pattern was observed for response times. Drift diffusion modelling analysis, however, suggested quicker evidence accumulation when under threat. Lastly, dwell times over the observer were higher when under threat, indicating a possible association between anxiety states and a bias towards potentially threat-related indicators. Future probing into this topic remains a necessity to better explain the current findings.