Application Of Ablation Research Articles

Abstract 13655: Relationship of Health-Related Social Needs, Social Determinants of Health, and Hospital Readmission Following Atrial Fibrillation Ablation

Introduction: Prior data report female sex, race, and impoverished populations by income and insurance status as less likely to receive atrial fibrillation (AF) ablation. Beyond this disparity, the impact of Social Determinants of Health (SocDH) in those that receive AF ablation and clinical outcomes is unknown. Using Health-Related Social Needs (HRSNs) as an indicator of SocDH, we assessed hospital readmissions after AF ablation. Methods: The 2010-2019 Nationwide Readmissions Database was queried for ICD-9/10 procedure and diagnosis codes for hospitalizations in which an adult patient underwent AF ablation and then stratified by presence of HRSNs (housing, socioeconomic status [SES], family, employment, and psychosocial) using Z-codes. Outcomes included all-cause 90-day readmission, and length of stay (LOS) and cost at index hospitalization. Unadjusted and adjusted regression models were estimated controlling for age, sex, and comorbidity burden. Results: An estimated 215,640 hospitalizations included AF ablation, of which 0.3% included a patient with a HRSN where housing and SES insecurity were the two most common HRSNs (43% and 40%, respectively). Hospitalizations including a HRSN tended to include younger patients (63 vs. 67 years), male (70% vs. 61%), a lower income quartile, with less private insurance (10% vs. 30%; all p < .001). HRSNs were associated with a 84% higher unadjusted odds of readmission (p < .001); although, this association was reduced to 15% after adjustment (p = .299). Readmission causes were identical between groups (18% and 15%, respectively). At index hospitalization, after adjustment, HRSNs were associated with 76% longer LOS (p < .001) and 7% higher hospital cost (p = .024). Conclusions: HRSNs/SocDH were associated with significant cost and LOS increases during index AF Ablation hospitalization. All-cause 90-day readmissions were increased, but not significant after adjustment for clinical factors. Compared to the general AF population, those receiving AF ablations had lower prevalence of HRSNs (0.3 vs. 0.9%). Further study on the impact of HRSNs in AF patients regarding rhythm control, AF ablation, and clinical outcomes is needed. A lower prevalence of HRSNs suggests a disparity in AF ablation application.

Thermal Ablation, Nonthermal Ablation And Surgical Striping Applications: 1-Year Single Center Early Results

ABSTRACT: Objectives : Starting from the 1900's minimally invasive methods such as endovenous laser ablation (EVLA), radiofrequency ablation (RFA), and ultrasound-guided foam sclerotherapy (UGFS) developed. Methods: This study includes a total of 136 patients (81 women/55 men), of whom 22 (10 women/12 men) were treated with classic surgical stripping, 54 (32 women/22 men) with thermal ablation and 60 (39 women/55 men) with non-thermal ablation. Results: Twenty-two patients (10 women/12 men) were treated with surgical stripping. In one female patient a hematoma arose in the medial crural region postoperatively. A radiofrequency catheter (ThermoBLOCK TM) was used in the thermal ablation procedures in 54 patients (32 female/22 male). It is believed that permanent paresthesia occured in one female patient after the procedure. In 3 male patients temporary paresthesia occured postoperatively. Non- thermal ablation was performed in 60 patients(39 female/55 male). Even through a severe burning sensation was present in 6 patients (5 female/1 male) during the procedure, this symptom was only transient. In one of the patients, deep venous thrombosis (DVT) occured at the level of the popliteal vein postoperatively at the sixth day. Conclusion: Even if thermal and non-thermal ablation and surgical procedures have the same pain decreasing rates, hematomas and a longer hospital stay are more frequent in surgical procedures.

Over than three-year follow-up results of thermal ablation for papillary thyroid carcinoma: A systematic review and meta-analysis.

This study is a meta-analysis based on evidence-based medicine to explore the long-term (≥3 years) efficacy of thermal ablation in the treatment of papillary thyroid carcinoma (PTC). We searched the PubMed, Embase, and Cochrane Library databases for studies published during the time between the establishment of the databases through June 2022. We included 13 non-randomized-controlled trials (non-RCTs) that reported the application of ultrasound-guided thermal ablation in PTC. We excluded studies that were repeated publications, research without full text, contained incomplete information, lacked data extraction, involved animal experiments, reviews, and systematic reviews. STATA 15.1 software was used to analyze the data. Tumor volume after thermal ablation at 3-year follow-up was significantly lower than pre-ablation (standardized mean difference [SMD] = -1.06, 95% CI: -1.32~-0.80). The pooled results indicated that the maximum diameter after thermal ablation at 3-year follow-up was significantly lower than pre-ablation (SMD = -1.93, 95% CI: -12.13~-1.73). The pooled results indicated that volume reduction rate (VRR) after thermal ablation at 3-year follow-up was 98.91% (95% CI: 97.98-99.83%), and complete disappearance rate (CDR) after thermal ablation at 3-year follow-up was 83% (95% CI: 67-94%). In addition, the incidence of newly discovered mPTC and lymph node metastases after thermal ablation was 0.3% (95% CI: 0.0-1.0%) and 0.0% (95% CI: 0.0-0.0%), respectively. Overall, the long-term (≥3 years) efficacy of ultrasound-guided thermal ablation in the treatment of PTC was significant, with favorable disease progression. Ultrasound-guided thermal ablation can be considered an alternative approach for patients with PTC who refuse surgery or are unable to undergo surgery.

Needle-Tipped Catheter Ablation of Papillary Muscle Results in Deeper and Larger Ablation Lesions.

Ventricular tachycardia associated with papillary muscle (PM) is often refractory to standard radiofrequency ablation (RFA). The needle-tipped ablation catheter (NT-AC) has been used to treat deep intramyocardial substrates, but its use for PM has not been characterized. Using an ex vivo experimental platform, both 3mm and 6mm NT-AC created larger ablation lesion volumes and depths than open-irrigated ablation catheter did (OI-AC; e.g., 57.12 ± 9.70mm3 and 2.42 ± 0.22mm, respectively; p < 0.01 for all comparisons). Longer NT-AC extension (6mm) resulted in greater ablation lesion volumes and maximum depths (e.g., 333.14 ± 29.13mm3 and 6.46 ± 0.29mm, respectively, compared to the shorter 3mm NT-AC extension, 143.33 ± 12.77mm3, and 4.46 ± 0.14mm; both p < 0.001). There were no steam pops. In conclusion, for PM ablation, the NT-AC was able to achieve ablation lesions that were larger and deeper than with conventional OI-AC. Ablation of PM may be another application for needle-tip ablation. Further studies are warranted to establish long-term safety and efficacy in human studies.

Pulsed laser ablation of cutting edge geometries in alumina and zirconia composites at 200 fs and 2 ps

In this study, the feasibility of lasermachining cutting edges into mixed oxide ceramics such as alumina toughened zirconia (ATZ) and zirconia toughened alumina (ZTA) is evaluated. A simplified standard wedge geometry is machined into cylindrical samples by combining orthogonal and quasi-tangential laser machining strategies. For the experiments a laser source emitting a wavelength of 515 nm is applied and the pulse duration is varied between 0.2 and 2 ps. As target parameters the cutting edge radius and Sa value of the rake face are analyzed. The heat affected zone is analyzed by FIB SEM. An edge radius of 6.7±1.6μm at an Sa value of 0.115μm in the case of ZTA and an edge radius of 4.9±0.3μm at an Sa value of 0.125μm in the case of ATZ can be achieved. The results are promising for the application of laser ablation towards the manufacturing of cutting edges in oxide ceramics such as ATZ and ZTA.

Perinatal and neurodevelopmental outcome in complicated monochorionic pregnancy after selective fetal reduction: radiofrequency ablation vs microwave ablation.

To summarize our experience in the application of radiofrequency ablation (RFA) and microwave ablation (MWA) for selective fetal reduction in complicated monochorionic pregnancies and compare the perinatal outcome of the two techniques. This was a retrospective study of data from a consecutive cohort of all monochorionic twin pregnancies that underwent selective fetal reduction with RFA or MWA at Peking University Third Hospital, Beijing, China from January 2012 to December 2018. All surviving cotwins were followed up to assess their neurodevelopment using the Age &amp; Stage Questionnaire, Chinese version. Perinatal and neurodevelopmental outcomes were compared between the RFA and MWA groups. We also fitted multivariable models to test the association between procedure-related factors and the main perinatal outcomes, including preterm birth (PTB) &lt; 37 weeks' gestation, intrauterine fetal death (IUFD) of the cotwin, adverse outcome (defined as occurrence of IUFD of the cotwin, termination of pregnancy or PTB &lt; 28 weeks) and overall survival. In total, 45 cases (42 twin and three triplet pregnancies) underwent RFA and 126 cases (105 twin and 21 triplet pregnancies) underwent MWA. The overall survival rates in monochorionic diamniotic twin pregnancies were similar between the RFA and MWA groups (61.0% vs 67.0%; P = 0.494). However, pregnancies whose indication for fetal reduction was selective intrauterine growth restriction or twin reversed arterial perfusion had higher overall survival rates (75.5% and 82.6%, respectively) compared with those in other indication groups. A total of 104 children were followed up (20 in the RFA group and 84 in the MWA group); four (20.0%) and eight (9.5%) children were assessed as having overall developmental delay in the RFA and MWA groups, respectively, with no significant difference between the two groups. Multivariable analyses showed that procedure indication, number of ablation cycles and gestational age at procedure were associated significantly with the main perinatal outcomes. RFA and MWA for selective fetal reduction in complicated monochorionic pregnancies can achieve similar overall survival rate and neurodevelopmental outcome, but MWA is associated with a lower risk of preterm birth. Moreover, procedure-related factors are associated significantly with perinatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Meta-Analysis of the Application Effect of Different Modalities of Thermal Ablation and Surgical Treatment in Papillary Thyroid Microcarcinoma.

Background Papillary thyroid microcarcinoma (PTMC) refers to papillary thyroid carcinoma (PTC) with a maximum diameter of 10 mm. Thermal ablation, including radiofrequency ablation (RFA), microwave ablation (MWA), and laser ablation (LA), has been applied in the treatment of benign thyroid nodules and captured extensive attention. At present, the application of thermal ablation in PTMC has been extensively reported, but outcomes such as volume reduction rate (VRR), complete remission rate (CRR), and adverse reaction rate (ARR) vary considerably. Therefore, this meta-analysis was performed to evaluate the safety and efficacy of different treatment methods of PTMC. Methods We did a systematic review and network meta-analysis. We searched PubMed, EMBase, and Cochrane-Library from the date of inception to January 10, 2022, to retrieve the VRR, CRR, and ARR of MWA, RFA, LA and surgical treatment of PTMC, and a meta-analysis was performed using the R meta-package. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and sensitivity analyses, cumulative meta-analyses, and publication bias were also performed. Relevant literature was retrieved with keywords; the eligible cohort studies were screened based on the established inclusion and exclusion criteria. Results A total of 1515 patients were included in the 12-month follow-up. The overall VRR was 86.25% (95% CI: 77.89, 94.60), and the VRR was RFA > WMA > LA, but the differences were not significant. A total of 1483 patients were included in the last follow-up. The overall VRR was 99.41% (95% CI: 99.11, 99.72), and the VRR was RFA > WMA > LA, but the differences were not significant. A total of 1622 patients showed complete remission at the last follow-up, and the overall CRR was 0.63 (95% CI: 0.46, 0.79). The CRR was RFA > LA > WMA, but the differences were not significant. A total of 1883 patients had adverse reactions at the last follow-up, and the overall ARR was 0.06 (95% CI: 0.03, 0.08). The ARR at the last follow-up was RFA = Surg < LA < WMA. The ARR of the RFA and Surg subgroups was significantly lower than that of the WMA subgroup. Conclusions Similar good efficacy and safety profiles were observed in WMA, RFA, LA, and surgical treatment in PTMC, among which RFA showed the best volume reduction, complete remission rate, and adverse reaction reduction. However, there is a slight bias in the limited literature included in this study, and we did not conduct or refer to mechanistic studies to confirm its specific mechanism of action. Clinicians are advised to use their discretion in the choice of treatment.

Feasibility and safety of three-dimensional electroanatomical cardiac mapping, mapping-guided biopsy and transseptal puncture in dogs

Three-dimensional electroanatomical mapping (3D EAM) has expanded radiofrequency catheter ablation applications in humans to almost all complex arrhythmias and has drastically reduced fluoroscopy use, yet its potential in dogs is poorly investigated. The objectives of the current study were to assess the feasibility and safety of 3D EAM of all four heart chambers, 3D EAM-guided biopsies and transseptal puncture in dogs. Eight healthy purpose-bred Beagle dogs. Electroanatomical mapping was performed under general anaesthesia during sinus rhythm using a 22-electrode mapping catheter. Left heart catheterisation was achieved by either retrograde transaortic access (n = 4) or transseptal puncture (n = 4). Successful 3D EAM of the right atrium and ventricle was achieved in all dogs at a median time of 33 (13–40) min and 17 (3–52) min, respectively. Left atrial and ventricular 3D EAM was successful in six and seven dogs, at a median time of 17 (4–27) min and 8 min (4–19 min), respectively. Complications requiring intervention occurred in one dog only and were a transient third degree atrioventricular block and pericardial effusion following transseptal puncture, which was treated by pericardiocentesis. All dogs recovered uneventfully. Fluoroscopy time was limited to a median of 7 min (0–45 min) and almost exclusively associated with transseptal puncture. Three-dimensional EAM of all cardiac chambers, including mapping-guided biopsy and transseptal puncture is feasible in small dogs. Complications are similar to those reported in human patients. This suggests a potential added value of 3D EAM to conventional electrophysiology in dogs with arrhythmias.

Long-term Outcomes after Second-Generation Cryoballoon Ablation of Atrial Fibrillation and Analysis of Risk Factors Related to Recurrence

Objective: This study is aimed to analyze the long-term safety and effectiveness of second-generation cryoballoon (CB2) ablation in the treatment of atrial fibrillation (AF). Methods: Data from 760 consecutive patients in the Department of Cardiology, General Hospital of Northern Theater Command from August 2016 to December 2018 with drug-refractory symptomatic AF undergoing pulmonary vein isolation (PVI) using CB2 were assessed. Procedure-related safety and freedom from AF and atrial flutter/atria tachycardia through 3 years were determined. The risk factors related to atrial tachyarrhythmia recurrence were analyzed. Results: Acute PVI was achieved in 100% of the 760 patients. Radiofrequency application for additional focal ablation was needed in 11 (1.4%) patients and for 14 pulmonary veins (0.5%, 14/(760 × 4)) to achieve PVI. A total of 748 patients, including 539 with paroxysmal AF (PAF) and 209 with persistent AF (SAF) completed the follow-up, and only 12 (1.6%) patients were lost. The mean follow-up duration was (19 ± 8) months. The rate of major complications was 0.9%, including 0.8% of right phrenic nerve injury, which resolved before discharge. Freedom from all tachyarrhythmias was achieved in 75.0%, 69.4%, and 63.2% of patients with PAF, respectively, at 12-, 24-, and 36-month follow-up, and in 75.1%, 67.4%, and 60.9% for SAF, with no significant differences between the PAF and SAF groups. AF course and the rate of body weight gain were independent risk factors for recurrence at 12 months after ablation (P = 0.001 and P = 0.009, respectively). Conclusion: PVI using CB2 has a high acute success rate and good safety in the treatment of PAF and SAF. Long course of AF and weight gain after ablation were independent risk factors for recurrence.

Best Practice Guidelines on the Diagnosis and Treatment of Vertebrogenic Pain with Basivertebral Nerve Ablation from the American Society of Pain and Neuroscience.

Chronic low back pain is a worldwide leading cause of pain and disability. Degenerative disc disease has been the presumptive etiology in the majority of cases of chronic low back pain (CLBP). More recent study and treatments have discovered that the vertebral endplates play a large role in CLBP in a term defined as vertebrogenic back pain. As the vertebral endplates are highly innervated via the basivertebral nerve (BVN), this has resulted in a reliable target in treating patients suffering from vertebrogenic low back pain (VLBP). The application of BVN ablation for patients suffering from VLBP is still in its early stages of adoption and integration into spine care pathways. BVN ablation is grounded in a solid foundation of both pre-clinical and clinical evidence. With the emergence of this therapeutic option, the American Society of Pain and Neuroscience (ASPN) identified the need for formal evidence-based guidelines for the proper identification and selection of patients for BVN ablation in patients with VLBP. ASPN formed a multidisciplinary work group tasked to examine the available literature and form best practice guidelines on this subject. Based on the United States Preventative Task Force (USPSTF) criteria for grading evidence, gives BVN ablation Level A grade evidence with high certainty that the net benefit is substantial in appropriately selected individuals.

Ultrasound-guided thermal ablation versus laparoscopic surgery for focal nodular hyperplasia of the liver: A retrospective controlled study.

PurposeThis study aims to evaluate the value of the clinical application of ultrasound-guided percutaneous thermal ablation in focal nodular hyperplasia (FNH) by comparing its safety, effectiveness, and patient experience to surgery in the treatment of hepatic FNH ≤5 cm.MethodThis retrospective study enrolled 82 patients with hepatic FNH having a maximum diameter of ≤5 cm, confirmed by postoperative pathologic diagnosis or needle biopsy, who underwent thermal ablation or surgery between January 2019 and September 2021. Postoperative efficacy, surgical trauma (operation time, intraoperative bleeding volume, liver function, and lost volume of normal liver tissue), postoperative complications (postoperative infection, pleural effusion, and liver dysfunction), patient experience (degree and time of postoperative pain, postoperative fasting time, indwelling thoracic chest drain, and scar size), and economic indices (postoperative hospitalization and total charges) were compared between both groups.ResultNo significant difference existed in postoperative efficacy between both groups (p > 0.05). No recurrent or new lesions were observed during the 6-month follow-up in both groups. However, significant differences were observed in operation time, intraoperative bleeding volume, and lost volume of normal liver tissue (p < 0.05), with significantly less trauma in the thermal ablation group. No statistically significant differences in ALT, AST, and Hb existed between both groups (p > 0.05); however, albumin was higher in the ablation group compared to the surgery group (38.21 ± 3.32 vs. 34.84 ± 3.71 g/L, p < 0.05), and WBC were lower in the ablation group (11.91 ± 3.37 vs. 13.94 ± 3.65/L, p < 0.05). The incidence of postoperative complications in the ablation group was significantly lower than that in the surgery group (p < 0.05). Patient experiences were significantly better than in the surgical group (p < 0.05), with economic indicators being significantly less in the ablation group (p < 0.05).ConclusionUltrasound-guided percutaneous thermal ablation can treat hepatic FNH ≤5 cm with similar clinical efficacy as surgery and is an economical, safe, and minimally invasive treatment method worthy of recommendation.

Efficacy of radiofrequency ablation for metastatic papillary thyroid cancer with and without initial biochemical complete status.

ObjectiveThe application of radiofrequency ablation (RFA) for recurrent thyroid cancer has been demonstrated to effectively manage lesions at critical locations, such as abutting the trachea, with limited complications. Comprehensive investigation of both biochemical (B) and structural (S) change after RFA remains limited. We herein present the first single-center experience of RFA for the treatment of locoregional recurrent thyroid cancer in Taiwan.Design23 patients were enrolled, and the treatment responses after RFA were divided into four groups (E, S(+), B(+), and SB(+)), and then compared. The RFA technique, follow-up strategy, changes in pre-and post-operative status, and complications are presented. The volume reduction rate at 1, 3, and 6 months, and the differing responses between lesions abutting/not abutting the trachea are also discussed.ResultsIn patients with pre-RFA structural and biochemical incomplete (SB(+)) status, presenting with lesion with an initial maximum diameter of >3.2cm, a higher rate of structural incomplete status at the 6-month follow-up was noted in ROC analysis, with a sensitivity of 57% and specificity of 91%. Favorable structural remission after RFA was noted, and 60.9% of patients achieved biochemical complete status. No significant correlation was noted between the trachea-abutted lesion number and complete remission (p= 0.474). No significant difference in RFA efficacy was noted between the lesions abutting/not abutting the trachea.ConclusionsThis retrospective study reveals that RFA can achieve both structural and biochemical improvements for locoregionally recurrent thyroid cancer, with a low complication rate. Nearly half of the patients achieved an excellent response after RFA, while a favorable treatment response can be achieved despite the lesion abutting the trachea, with a mean VRR of 84.74%.

MoSBOTs: Magnetically Driven Biotemplated MoS2 -Based Microrobots for Biomedical Applications.

2D layered molybdenum disulfide (MoS2 ) nanomaterials are a promising platformfor biomedical applications, particularly due to its high biocompatibility characteristics, mechanical and electrical properties, and flexible functionalization. Additionally, the bandgap of MoS2 can be engineered to absorb light over a wide range of wavelengths, which can then be transformed into local heat for applications in photothermal tissue ablation and regeneration. However, limitations such as poor stability of aqueous dispersions and low accumulation in affected tissues impair the full realization of MoS2 for biomedical applications. To overcome such challenges, herein, multifunctional MoS2 -based magnetic helical microrobots (MoSBOTs) using cyanobacterium Spirulina platensis are proposed as biotemplate for therapeutic and biorecognition applications. The cytocompatible microrobots combine remote magnetic navigation with MoS2 photothermal activity under near-infrared irradiation. The resulting photoabsorbent features of the MoSBOTs are exploited for targeted photothermal ablation of cancer cells and on-the-fly biorecognition in minimally invasive oncotherapy applications. The proposed multi-therapeutic MoSBOTs hold considerable potential for a myriad of cancer treatment and diagnostic-related applications, circumventing current challenges of ablative procedures.

EE289 Ablation Index in Catheter Ablation of Atrial Fibrillation: A Cost-Utility Analysis in Belgium and Germany

Catheter ablation is a commonly used therapy for symptomatic nonvalvular atrial fibrillation (AF). VISITAG SURPOINT™ (Ablation Index/AI) is a module that allows annotation and tagging of ablation applications. Ablation with AI is associated with a significant reduction in atrial arrhythmia recurrence at 12 months versus ablation with catheters alone in meta-analyses. The objective of this study was to assess the cost-effectiveness of AI for catheter ablation versus ablation with catheters alone in adult patients with drug-refractory paroxysmal or persistent AF from the German and Belgium healthcare payer’s perspectives.

Extraction of Floating Raft Aquaculture Areas from Sentinel-1 SAR Images by a Dense Residual U-Net Model with Pre-Trained Resnet34 as the Encoder

Marine floating raft aquaculture (FRA) monitoring is significant for marine ecological environment and food security assessment. Synthetic aperture radar-based monitoring is considered to be an effective means of FRA identification because of its capability for all-weather applications. Considering the poor generalization and extraction accuracy of traditional monitoring methods, a semantic segmentation model called D-ResUnet is proposed to extract FRA areas from Sentinel-1 images. The proposed model has a U-Net-like structure but combines the pre-trained ResNet34 as the encoder and adds dense residual units into the decoder. For this model, the final layer and cropping operation of the original U-Net model are removed to eliminate the model parameters. The mean and standard deviation of Precision, Recall, Intersection over Union (IoU), and F1 score are calculated under a five-fold training strategy to evaluate the model accuracy. The test experiments indicated that the proposed model performs well with the F1 of 92.6% and IoU of 86.24% in FRA extraction tasks. In particular, the ablation experiments and application experiments proved the effectiveness of the improvement strategy and the portability of the proposed D-ResUnet model, respectively. Compared with the other three state-of-the-art semantic segmentation models, the experiments demonstrate a clear accuracy advantage of the D-ResUnet model. For the FRA extraction task, this paper presents a promising approach that has refined extraction capability, high accuracy, and acceptable model complexity.

A method for constructing a mouse model of congenital hearing loss by bilateral cochlear ablation

BackgroundCochlear ablation is one of the most classic methods for the animal model establishment of hearing loss (HL), but the vast majority of rodents taken by cochlear ablation have been rats and adult mice so far. Given the importance of mice in HL studies, it is urgently necessary to expand the application of cochlear ablation in mice at different ages. New MethodBilateral cochlear ablation surgery was performed in C57BL/6 J mice before the onset of hearing at postnatal (P) day 10. Auditory brainstem response was performed to evaluate the hearing of mice. Open field test and swimming test were performed to examine the vestibular function of mice. ResultsA permanent HL model was built by bilateral cochlear ablation in C57BL/6 J mice at P10. This method could successfully destroy cochlear hair cells and cause no vestibular deterioration in the adulthood of mice. Comparison with Existing Method(s)In addition to transgenic mice, permanently deaf mice used in this field in the existing studies are restricted to a time point after their ear canal opening. This study is the first to establish a congenital and permanent HL mouse model by cochlear ablation without gene modification. ConclusionsBilateral cochlear ablation in mice at P10 is an ideal and effective way for congenital HL mice model foundation, and the vestibular function seems not to be deteriorated.

Novel tissue-pressure sensing technology using a wide-band dielectric imaging system: An in vivo study

BackgroundA novel dielectric wide-band imaging system with tissue pressure (TP) technology provides real-time contact force (CF) monitoring using non-CF catheters. This study sought to investigate the feasibility, safety, and efficacy of ablation with TP technology. MethodsEighty-five patients with supraventricular tachycardia (SVT) were ablated with real-time monitoring of CF by TP technology and compared with 85 patients who underwent ablation with a conventional non-TP approach. Baseline characteristics, procedural data, and TP data were analyzed in the study. Ablation applications in the TP group were then subdivided into good contact and poor contact groups according to the TP level for analysis. ResultsThe TP group had a significantly shorter procedural time (16.2 ± 6.9 min vs. 19.9 ± 10.0 min, p = 0.033), shorter ablation time (334.6 ± 166.9 s vs. 391.3 ± 195.7 s, p = 0.049), and fewer mean numbers of radiofrequency catheter ablation (RFCA) deliveries (6.2 ± 3.2 vs. 7.6 ± 5.2, p = 0.047) than the non-TP group. The achieved average percentage of TP >3 g was significantly higher in the good-contact group (97.94% vs. 15.48%, p < 0.001). The median impedance decreases during RFCA in the good contact group and poor contact group were 4.10 (0.30–6.88) Ω and 2.60 (−0.05–4.98) Ω at 10 s, 4.45 (0.58–8.25) Ω and 2.88 (0.23–5.70) Ω at 20 s, and 4.67 (1.95–9.08) Ω and 2.97 (−0.26–6.33) Ω at 30 s, respectively (p < 0.05 for comparisons between categories). All patients achieved acute success, and no complications were observed. Two patients in the TP group and one patient in the non-TP group experienced recurrence during follow-up. ConclusionTP-technology guided ablation of SVT is feasible, efficient, and safe.

Noise reduction in electrophysiological signals using transfer machine learning

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIH Background/Introduction Reducing electrophysiological signal noise is essential for diagnosis, mapping and ablation, yet most approaches are suboptimal. Template matching requires libraries of known signal types, that are difficult to obtain. Beat averaging can reduce noise, yet cannot be applied to single beats and obscures beat-to-beat variations. Beat smoothing can lose critical and subtle signal features. We set out to use neural networks (NN) based on encoder-decoders, which are able to extract key signal features and hence reconstruct them without noise and artifact. Purpose We hypothesised that electrograms with varying sources of artifact can be denoised using autoencoder neural networks. We further hypothesised that this could be achieved in a small data set by developing the method in a larger dataset of related signals, then using transfer learning. We tested this approach for atrial monophasic action potentials (MAPs) that have verifiable shapes. Methods The NN was first trained with 5706 left and right ventricular MAPs from 42 patients with ischemic cardiomyopathy (age 65±13y; fig 1.A): 60% for training, 20% (validation) and 20% (testing). Transfer learning and parameter-tuning were then used to apply this NN to a smaller sample of atrial MAPs (N=641, 21 patients, 67±5y, 13 women; fig D,F,H). Results The autoencoder was able to learn key features of MAPs, and hence reconstruct them without artifacts. NN learned ventricular MAPs with similarity coefficient 0.91±0.16, Pearson correlation 0.99± 0.01 (fig A) and learned key features (upstroke, triangular descent, terminus) to reduce noise (fig B-C). Applying this trained NN to atrial MAPs, the approach automatically eliminated ventricular artifact (fig E), high frequency noise (fig G), truncation (fig I), saturation and other artifacts. After fine-tuning, the NN reconstructed atrial MAPs with Pearson correlation = 0.99±0.01 (p&amp;lt;0.001). Conclusions Machine learned encoder-decoders are powerful tools that can automatically eliminate diverse types of noise in single beats by learning essential signal features. Transfer learning makes this possible without large datasets for training, even from signals in a different cardiac chamber. This approach may have far-reaching applications for mapping and ablation.

Zero- and minimal fluoroscopic approaches during ablation of supraventricular tachycardias: A systematic review and meta-analysis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Catheter ablations for cardiac arrhythmias are conventionally performed under fluoroscopic guidance. Using three dimensional electroanatomical mapping systems to guide these procedures, zero/minimal fluoroscopy (Z/MF) approaches became available. Purpose Our aim was to conduct a meta-analysis comparing these two different methods for the treatment of paroxysmal supraventricular tachycardias (SVT). Methods Electronic databases were searched and systematically reviewed for studies comparing procedural parameters and outcomes of conventional, fluoroscopy-guided vs. Z/MF approaches in patients undergoing EP procedures for SVTs. The random-effects model was used to derive mean difference (MD) and risk ratios (RR) with 95÷ confidence interval (CI). Results 24 studies involving 9,074 patients met our inclusion criteria. There were no differences between the groups in acute success (RR=1.00, 95÷ CI, 0.99–1.01; p=0.97) and long-term success rate (RR: 1.01, 95÷ CI, 1.00–1.03; p=0.13). Compared to the conventional method, Z/MF ablation significantly reduced fluoroscopic time (MD: -10.95 min (95÷ CI, -18.43 to -3.46 min; p&amp;lt;0.01)) and ablation time (MD: -25.23 s (95÷ CI: -42.04 to -8.43 s; p&amp;lt;0.01)). Procedure time (MD: 3.06 min (95÷ CI: -0.97 to 7.08; p=0.14)) and number of ablation applications (MD: 0.13 (95÷ CI: -0.86 to 1.11; p=0.80)) were not different between the groups. Complication rate was 1.59% in the entire study population and did not differ among the groups (RR: 0.68, 95÷ CI: 0.45–1.05; p=0.08). Conclusions Z/MF approach for the catheter ablation of SVTs is a feasible method that reduces radiation exposure and ablation time but does not compromise the acute and long-term success, or complication rates.

In vivo porcine characterization of atrial lesion safety and efficacy utilizing a circular pulsed-field ablation catheter including assessment of collateral damage to adjacent tissue in supratherapeutic ablation applications.

IntroductionPulsed‐field ablation (PFA), an ablative method that causes cell death by irreversible electroporation, has potential safety advantages over radiofrequency ablation and cryoablation. Pulmonary vein (PV) isolation was performed in a porcine model to characterize safety and performance of a novel, fully‐integrated biphasic PFA system comprising a multi‐channel generator, variable loop circular catheter, and integrated PFA mapping software module.MethodsEight healthy porcine subjects were included. To evaluate safety, multiple ablations were performed, including sites not generally targeted for therapeutic ablation, such as the right inferior PV lumen, right superior PV ostium, and adjacent to the esophagus and phrenic nerve. To evaluate the efficacy, animals were recovered, followed for 30(±3) days, then re‐mapped. Gross pathological and histopathological examinations assessed procedural injuries, chronic thrombosis, tissue ablation, penetration depth, healing, and inflammatory response.ResultsAll eight animals survived follow‐up. PV narrowing was not observed acutely nor at follow‐up, even when ablation was performed deep to the PV ostium. No injury was seen grossly or histologically in adjacent structures. All PVs were durably isolated, confirmed by bidirectional block at re‐map procedure. Histological examination showed complete, transmural necrosis around the circumference of the ablated section of right PVs.ConclusionThis preclinical evaluation of a fully‐integrated PFA system demonstrated effective and durable ablation of cardiac tissue and PV isolation without collateral damage to adjacent structures, even when ablation was performed in more extreme settings than those used therapeutically. Histological staining confirmed complete transmural cell necrosis around the circumference of the PV ostium at 30 days.