Search

Background: Personalized radiofrequency (RF) ablation for paroxysmal atrial fibrillation (PAF), adapting the ablation index (AI) to local left atrial wall thickness (LAWT), proved to be highly efficient maintaining high arrhythmia-free survival rates. However, multicentre data are lacking. This multicentre, prospective, non-randomized study was conducted at 5 tertiary hospitals and sought to assess the safety, efficacy, and reproducibility of the LAWT-guided ablation for PAF., Methods: Consecutive patients referred for first-time PAF were prospectively enrolled. The LAWT maps were obtained from preprocedural multidetector computed tomography and integrated into the navigation system. AI was titrated according to the local LAWT, and the ablation line was personalized to avoid the thickest regions while encircling the pulmonary veins (PVs)., Results: A total 109 patients (60.1 ± 9.4 years, 64.2% male) were enrolled. Median procedure time was 61.7 min (48.4-83.8), fluoroscopy time was 1.0 min (0.4-3.3), and RF time was 13.9 min (12.3-16.8). Median AI tailored to the local LAWT was 393 (374-412) for the anterior wall and 340 (315-378) for the posterior wall. Right and left PVs first-pass isolation was achieved in 89% and 91.7% of the patients, respectively. At 12-month follow-up, freedom from any atrial arrhythmia was 93.4% (95% CI 88.7-98.1), without differences across centres (P = 0.169). One patient experienced femoral artery pseudoaneurysm, with no other serious procedural-related complication., Conclusion: The Ablate-by-LAWT study proved that LAWT-guided PV isolation for PAF is safe, effective, and efficient in a multicentre setting. Twelve-month recurrence-free survival exceeded 90% (NCT04218604)., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Epicardial access is often crucial for successful ventricular tachycardia (VT) ablation, but it is often burdened by significant procedural risk. Intentional coronary vein exit and intrapericardial CO 2 insufflation (EpiCO 2 ) can facilitate subxiphoid pericardial access., Objective: This prospective study aimed to assess procedural feasibility, safety, and impact of the introduction of intrapericardial CO 2 insufflation for epicardial access in a referral center for VT ablation., Methods: All consecutive patients treated with epicardial VT ablation between November 2022 and January 2024 with the EpiCO 2 technique at Pisa University Hospital were prospectively enrolled and compared in terms of feasibility, efficiency, and safety with a local retrospective cohort of patients treated with subxiphoid dry puncture between July 2018 and October 2022., Results: Twenty-two consecutive patients (90.9% male; mean age, 54.3 years) underwent VT ablation with EpiCO 2 during the study period. Epicardial access was achieved in all patients; median time from coronary sinus (CS) cannulation to epicardial access was 33 minutes. Intentional vein exit was successful in all cases, whereas CO 2 insufflation was not feasible in 1 patient. There were no major complications and no significant bleeding. Since EpiCO 2 introduction, epicardial approach utilization increased from 17.8% to 40% of all VT procedures. Comparison with 20 standard dry approach epicardial ablations showed no significant differences in terms of total procedural duration (322.5 [interquartile range, 296.75-363.75] minutes vs 359 [interquartile range, 323-409] minutes; P = .08)., Conclusion: In our single-center experience, EpiCO 2 was feasible and safe and led to significant increase in procedural volume without affecting total procedural time compared with standard dry puncture., Competing Interests: Disclosures The authors have no conflicts to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: The isolated tricuspid valve (TR) has evolved into an entity in its own right. In contrast to TR treatment in left valve surgery, the benefit of surgery for isolated TR remains controversial. In this context, transcatheter valve interventions (TTVI) are becoming increasingly important. In this report, we present our experience with TricValve in a single center., Methods: From March 2022 to September 2023, 13 patients with at least severe isolated TR were scheduled for TricValve implantation. The mean age was 81 years (77-87), 5 were female and 8 were male. All patients were older than 70 years and had at least severe TR, hepatic or peripheral congestion and high surgical risk., Results: No procedure failure or device embolization was recorded. One case died in hospital 6 days after implantation and 1 case died after 124 days from irreversible renal and hepatic failure. The survival rate was 80.2% ± 12.8; the proportion of patients in NYHA class I increased significantly to 45% at follow-up. Among the 11 survivors, the median NT -proBNP decreased from 2873 to 148 pg/mL at follow-up (p = 0.003). In addition, a significant reduction in furosemide dosage from 125 mg to 50 mg at follow-up was observed over time. Finally, TR grade improved significantly along with RV size., Conclusions: This procedure appears to be safe and effective in carefully selected patients. Given the extreme simplicity of the procedure, the TricValve will increasingly represent one of the most viable treatment options for this patient group in the future., (Copyright © 2024. Published by Elsevier B.V.)

The use of wheat middlings (WM) and rice husks (RH) as biofillers for mixing with poly(lactic acid) (PLA) matrix to produce new 3D-printable biocomposites was assessed. Filaments containing 10 and 20 wt.% agro-waste-derived biofillers were manufactured and, for the sake of comparison, filaments of neat PLA were also produced. The obtained filaments were characterized via thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), showing potential for further application in additive manufacturing processing. Three-dimensionally printed specimens were thus produced and characterized via: DSC, also evaluating the specific heat capacity (CP) of specific 3D-printed specimens; dynamic mechanical analysis (DMA), also applied for determining the coefficient of linear thermal expansion (CLTE) measured on 3D-printed specimens in two different directions ( X and Y ); and tensile tests. The latter testing campaign was carried out along three printing directions ( X , Y , and Z axes) to test the intrinsic biocomposite features ( X -printed samples) as well as interbead and interlayer adhesion ( Y - and Z -printed specimens, respectively). All samples demonstrated acceptable properties. The inclusion of a cost-free natural material leads to a strong reduction of the whole material cost. Implementing this new class of composite material to an additive manufacturing technique can significantly reduce the environmental impact of 3D-printed products.

Artificial Intelligence (AI) applications and Machine Learning (ML) methods have gained much attention in recent years for their ability to automatically detect patterns in data without being explicitly taught rules. Specific features characterise the ECGs of patients with Brugada Syndrome (BrS); however, there is still ambiguity regarding the correct diagnosis of BrS and its differentiation from other pathologies. This work presents an application of Echo State Networks (ESN) in the Recurrent Neural Networks (RNN) class for diagnosing BrS from the ECG time series. 12-lead ECGs were obtained from patients with a definite clinical diagnosis of spontaneous BrS Type 1 pattern (Group A), patients who underwent provocative pharmacological testing to induce BrS type 1 pattern, which resulted in positive (Group B) or negative (Group C), and control subjects (Group D). One extracted beat in the V2 lead was used as input, and the dataset was used to train and evaluate the ESN model using a double cross-validation approach. ESN performance was compared with that of 4 cardiologists trained in electrophysiology. The model performance was assessed in the dataset, with a correct global diagnosis observed in 91.5 % of cases compared to clinicians (88.0 %). High specificity (94.5 %), sensitivity (87.0 %) and AUC (94.7 %) for BrS recognition by ESN were observed in Groups A + B vs. C + D. Our results show that this ML model can discriminate Type 1 BrS ECGs with high accuracy comparable to expert clinicians. Future availability of larger datasets may improve the model performance and increase the potential of the ESN as a clinical support system tool for daily clinical practice., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Federico Vozzi reports financial support was provided by Tuscany Region., (© 2024 The Authors.)

Purpose: We evaluated the clinical impact of the high-density (HD) mapping compared with the standard low-density (LD) ablation catheter mapping technique in the treatment of AFLs., Methods: We retrospectively evaluated short and long outcomes of patients approached with an HD and a LD electro-anatomical strategy for atypical AFLs., Results: Eighty-seven patients were included. Patients were almost male (60%), relatively old (65 ± 8 years), with a moderate CHA2DS2Vasc score (2.3 ± 1.3), a preserved ejection fraction (58 ± 6), and moderate atrial dilatation (44 ± 7 mm). Baseline clinical characteristics were comparable between groups (p = NS). Among AFLs, 10 (11%) were located in the right and 78 (89%) in the left atrium, including 22 (28%) roof dependent and 37 (47%) mitral dependent (p = NS). Sinus rhythm restoration during ablation was more frequently observed in the HD group (79% vs 56%, p = 0.037), without differences in mapping time, procedural time, and radiological dose (p = NS). Overall AFL/AT/AF recurrence rate at 1, 2, and 3 years was lower in the HD group (14% vs 37% p = 0.02, 14% vs 48% p = 0.002 and 14% vs 50% p < 0.001, respectively) with a time-dependent trend only in the LD group (37% vs 48% vs 50% at 1, 2, and 3 years respectively, p = 0.059). HD mapping (OR 0.17; 95% CI 0.04-0.66) and younger age (OR 1.09; 95% CI 1.01-1.19) resulted independent predictors of overall arrhythmias at follow-up., Conclusions: Short- and long-term outcomes of atypical AFL ablation were better in the case of HD mapping, which resulted independent predictor of arrhythmia recurrences., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Vat photopolymerization, a very efficient and precise object manufacturing technique, still strongly relies on the use of acrylate- and methacrylate-based formulations because of their low cost and high reactivity. However, the environmental impact of using fossil fuel-based, volatile, and toxic (meth)acrylic acid derivatives is driving the scientific community toward the development of alternatives that can match the mechanical performance and three-dimensional (3D) printing processability of traditional photocurable mixtures but are made from environmentally friendly building blocks. Herein, itaconic acid is polymerized with polyols derived from naturally occurring terpenes to produce photocurable poly(ester-thioether)s. The formulation of such polymers using itaconic acid-based reactive diluents allows the preparation of a series of (meth)acrylate-free photocurable resins, which can be 3D printed into solid objects. Extensive analysis has been conducted on the properties of photocured polymers including their thermal, thermomechanical, and mechanical characteristics. The findings suggest that these materials exhibit properties comparable to those of traditional alternatives that are created using harmful and toxic blends. Notably, the photocured polymers are composed of biobased constituents ranging from 75 to 90 wt %, which is among the highest values ever recorded for vat photopolymerization applications., Competing Interests: The authors declare no competing financial interest., (© 2023 American Chemical Society.)

The search for alternative ways to give a second life to materials paved the way for detailed investigation into three silica-polyethylenimine (Si-PEI) materials for the purpose of CO 2 adsorption in carbon capture and storage. A solvent extraction procedure was investigated to recover degraded PEIs and silica, and concomitantly, pyrolysis was evaluated to obtain valuable chemicals such as alkylated pyrazines. An array of thermal (TGA, Py-GC-MS), mechanical (rheology), and spectroscopical (ATR-FTIR, 1 H- 13 C-NMR) methods were applied to PEIs extracted with methanol to determine the relevant physico-chemical features of these polymers when subjected to degradation after use in CO 2 capture. Proxies of degradation associated with the plausible formation of urea/carbamate moieties were revealed by Py-GC-MS, NMR, and ATR-FTIR. The yield of alkylpyrazines estimated by Py-GC-MS highlighted the potential of exhausted PEIs as possibly valuable materials in other applications.

Background: Existing data on the impact of sex differences on transvenous lead extraction (TLE) outcomes in cardiac device patients are limited., Objective: The purpose of this study was to evaluate the safety and efficacy of mechanical TLE in female patients., Methods: A retrospective evaluation was performed on 3051 TLE patients (group 1: female; group 2: male) from a single tertiary referral center. All individuals received treatment using single sheath mechanical dilation and various venous approaches as required., Results: Our analysis included 3051 patients (group 1: 750; group 2: 2301), with a total of 5515 leads handled with removal. Female patients were younger, had a higher left ventricular ejection fraction, and lower prevalences of coronary artery disease and diabetes mellitus. Infection was more common in male patients, whereas lead malfunction or abandonment were more frequent in female patients. Radiologic success was lower in female patients (95.8% vs 97.5%; P = .003), but there was no significant difference in clinical success between groups (97.2% vs 97.5%; P = .872). However, major complications (1.33% vs 0.60%; P <.001) and procedural mortality (0.4% vs 0.1%; P <.001) were higher in females compared to male patients. After multivariate analysis, female sex emerged as the only predictor of major complications, including deaths (odds ratio 3.96; 95% confidence interval 1.39-11.24)., Conclusion: TLE using unpowered simple mechanical sheaths in female patients is safe and effective, but is associated with lower radiologic success and higher complication rates and mortality than in males. This finding underscores the importance of recognizing sex differences in TLE outcomes., (© 2023 Heart Rhythm Society. Published by Elsevier Inc.)

High-power short-duration (HPSD) ablation is an increasingly used ablation strategy for pulmonary vein isolation (PVI) procedures, but Lesion Index (LSI)-guided HPSD radiofrequency (RF) applications have not been described in this clinical setting. We evaluated the procedural efficiency and safety of an LSI-guided HPSD strategy for atrial fibrillation (AF) ablation. Paroxysmal and persistent AF patients scheduled for AF ablation were prospectively enrolled and divided into two groups, according to the ablation power used (≥45 W for the LSI-HP Group and ≤40 W for the LSI-LP group). All patients underwent only PVI LSI-guided ablation (5.5 to 6 anteriorly; 5 to 5.5 superiorly, 4.5 to 5 posteriorly) with a point-by-point strategy and an inter-lesion distance <6 mm. Forty-six patients with AF (25 in the LSI-HP Group vs 21 in the LSI-LP Group)-59% paroxysmal, 78% male, with low-intermediate CHA 2 DS 2 -Vasc scores (2 [1-3]), a preserved ejection fraction (65 ± 6%) and a mean left atrial index volume of 39 ± 13 mL/m 2 were prospectively enrolled. Baseline clinical characteristics were comparable between groups. PVI was successful in all patients. The RF time (29 (23-37) vs. 49 (41-53) min, p < 0.001), total procedure time (131 (126-145) vs. 155 (139-203) min, p = 0.007) and fluoroscopy time (12 (10-18) vs. 21 (16-26) min, p = 0.001) were significantly lower in the LSI-HP Group. No complications or steam pops were seen in either group. LSI-HP AF ablation significantly improved procedural efficiency-reducing ablation time, total procedural duration, and fluoroscopy use, while maintaining a comparable safety profile to lower-power procedures.

Introduction: Transcatheter atrial fibrillation (AF) ablation is still carried out with continuous invasive radial arterial blood pressure (IBP) monitoring in many centers. Continuous noninvasive blood pressure (CNBP) measurement using the volume-clamp method is a noninvasive alternative method used in ICU. No data on CNBP reliability are available in the electrophysiology lab during AF ablation, where rhythm variations are common., Background: The objective of the present study was to compare continuous noninvasive arterial pressure measured with the ClearSight device (Edwards Lifesciences, Irvine, CA, USA) with invasive radial artery pressure used as the reference method during AF ablation., Methods: We prospectively enrolled 55 consecutive patients (age 62 ± 11 years, 80% male) undergoing transcatheter AF ablation (62% paroxysmal, 38% persistent) at our center. Standard of care IBP monitoring via a radial cannula and a contralateral noninvasive finger volume-clamp CNBP measurement device were positioned simultaneously in all patients for the entire procedure. Bland-Altman analysis was used to analyze the agreement between the two techniques., Results: A total of 1219 paired measurements for systolic, diastolic, and mean arterial pressure were obtained in 55 subjects, with a mean (SD) of 22 (9) measurements per patient. The mean bias (SD) was -12.97 (13.89) mmHg for systolic pressure (level of agreement -14.24-40.20; correlation coefficient 0.84), -1.85 (8.52) mmHg for diastolic pressure (level of agreement -18.54-14.84; correlation coefficient 0.77) and 2.31 (8.75) mmHg for mean pressure (level of agreement -14.84-19.46; correlation coefficient 0.85)., Conclusion: In patients undergoing AF ablation, CNBP monitoring with the ClearSight device showed acceptable agreement with IBP monitoring. Larger studies are needed to confirm the potential clinical implications of continuous noninvasive BP monitoring during AF ablation.

Catalysts are used for producing the vast majority of chemical products. Usually, catalytic membranes are inorganic. However, when dealing with reactions conducted at low temperatures, such as in the production of fine chemicals, polymeric catalytic membranes are preferred due to a more competitive cost and easier tunability compared to inorganic ones. In the present work, nanofibrous mats made of poly(ethylene oxide), PEO, and poly(ethylene glycol) diacrylate, PEGDA, blends with the Au/Pd catalyst are proposed as catalytic membranes for water phase and low-temperature reactions. While PEO is a water-soluble polymer, its blending with PEGDA can be exploited to make the overall PEO/PEGDA blend nanofibers water-resistant upon photo-crosslinking. Thus, after the optimization of the blend solution (PEO molecular weight, PEO/PEGDA ratio, photoinitiator amount), electrospinning process, and UV irradiation time, the resulting nanofibrous mat is able to maintain the nanostructure in water. The addition of the Au 6 /Pd 1 catalyst (supported on TiO 2 ) in the PEO/PEGDA blend allows the production of a catalytic nanofibrous membrane. The reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), taken as a water phase model reaction, demonstrates the potential usage of PEO-based membranes in catalysis.

The development of electronic skins and wearable devices is rapidly growing due to their broad application fields, such as for biomedical, health monitoring, or robotic purposes. In particular, tactile sensors based on piezoelectric polymers, which feature self-powering capability, have been widely used thanks to their flexibility and light weight. Among these, poly(vinylidenefluoride-trifluoroethylene) (PVDF-TrFE) presents enhanced piezoelectric properties, especially if manufactured in a nanofiber shape. In this work, the enhanced piezoelectric performances of PVDF-TrFE nanofibers were exploited to manufacture a flexible sensor which can be used for wearable applications or e-skin. The piezoelectric signal was collected by carbon black (CB)-based electrodes, which were added to the active layer in a sandwich-like structure. The sensor was electromechanically characterized in a frequency range between 0.25 Hz and 20 Hz-which is consistent with human activities (i.e., gait cycle or accidental bumps)-showing a sensitivity of up to 4 mV/N. The parameters of the signal acquisition circuit were tuned to enable the sensor to work at the required frequency. The proposed electrical model of the nanofibrous piezoelectric sensor was validated by the experimental results. The sensitivity of the sensor remained above 77.5% of its original value after 10 6 cycles of fatigue testing with a 1 kN compressive force.