Accurate Temperature Reconstruction in Radiofrequency Ablation for Atherosclerotic Plaques Based on Inverse Heat Transfer Analysis

Radio frequency ablation has emerged as a widely accepted treatment for atherosclerotic plaques. However, monitoring the temperature field distribution in the blood vessel wall during this procedure presents challenges. This limitation increases the risk of endothelial cell damage and inflammatory responses, potentially leading to lumen restenosis. The aim of this study is to accurately reconstruct the transient temperature distribution by solving a stochastic heat transfer model with uncertain parameters using an inverse heat transfer algorithm and temperature measurement data. The nonlinear least squares optimization method, Levenberg-Marquardt (LM), was employed to solve the inverse heat transfer problem for parameter estimation. Then, to improve the convergence of the algorithm and reduce the computational resources, a method of parameter sensitivity analysis was proposed to select parameters mainly affecting the temperature field. Furthermore, the robustness and accuracy of the algorithm were verified by introducing random noise to the temperature measurements. Despite the high level of temperature measurement noise (ξ = 5%) and larger initial guess deviation, the parameter estimation results remained closely aligned with the actual values, with an overall ERMS consistently below 0.05. The absolute errors between the reconstruction temperature at the measurement points TC1, TC2, and TC3, and the actual temperature, remained within 0.33 °C, 2.4 °C, and 1.17 °C, respectively. The Levenberg-Marquardt algorithm employed in this study proficiently tackled the ill-posed issue of inversion process and obtained a strong consistency between the reconstructed temperature the actual temperature.

transcatheter arterial embolization for hepatic hemangiomas

OBJECTIVE

The objective of this study was to evaluate the safety and effectiveness of radiofrequency ablation (RFA) and transcatheter arterial chemoembolization (TACE) in the treatment of large hepatic hemangiomas (LHH) (5-9.9 cm in diameter).

METHODS AND MATERIALS

This study retrospectively collected data from 82 patients with LHH treated at Chaoyang Central Hospital. The study analyzed the differences in postoperative efficacy, operative time, blood routine, liver and kidney function on the first day after surgery, postoperative hospitalization time and postoperative complications.

RESULTS

There were statistically significant differences in indicators such as white blood cell count, alanine aminotransferase, aspartate aminotransferase and total bilirubin on the first day after surgery between the RFA group (39 cases) and the TACE group (43 cases) ( P  < 0.001). Compared to RFA, LHH patients treated with TACE had a general complication rate of 39.5% (vs. 43.6%; P  = 0.7), a procedure-related complication rate of 30.2% (vs. 59.0%; P  = 0.009), an effective rate at 6-12 months postoperatively of 55.8% (vs. 82.1%; P  = 0.01), an operating-time of 41.2 ± 14.9 min (vs. 100.8 ± 35.5 min; P  < 0.001) and hospitalization costs of 17052.7 ± 1364.8 yuan (vs. 30952.1 ± 4327.6 yuan; P  < 0.001).

CONCLUSION

This study indicates that the efficacy of RFA in treating LHH is significantly superior to TACE. Microwave ablation and RFA appear to be safe treatments for LHH. The TACE group exhibited shorter operating-time, lower hospitalization costs and lower demands on cardiopulmonary function.

The Application of Radiofrequency Ablation in Acute and Chronic Pain Management

Radiofrequency ablation (RFA), also known as rhizotomy, is one of the frequently used modalities in interventional pain management. This nonsurgical procedure delivers radiofrequency waves to the targeted nerves to interrupt transmission of nociceptive signals from the peripheral tissues to the central nervous system, thereby reducing pain perception. Recent studies have demonstrated the efficacy of RFA treatment as an effective interventional pain management technique to treat a variety of acute and chronic pain conditions including facial pain, headaches, postmastectomy, musculoskeletal, and major joint pain (knee, hip, shoulder, sacroiliac), and cancer pain. As more certified registered nurse anesthetists are involved in pain management, it is important to be familiar with current nonsurgical pain interventions. This journal course describes the unique mechanism of action of radiofrequency for pain modulation and provides emerging evidence to support its applications in both acute and chronic pain management.

ENDOSCOPIC ULTRASOUND-GUIDED RADIOFREQUENCY ABLATION FOR PANCREATIC ADENOCARCINOMA

BACKGROUND AND AIMS

Emerging data suggest neoadjuvant chemotherapy (NAC) for resectable pancreatic ductal adenocarcinoma (PDAC) is associated with improved survival. However, less than 40% demonstrate a meaningful radiographic response to NAC. Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as a new modality to treat PDAC. We hypothesize that NAC plus EUS-RFA can be used in the management of resectable PDAC.

METHODS

Prospective review of PDAC patients meeting criteria of resectable tumor anatomy that underwent NAC chemotherapy plus EUS-RFA followed by pancreatic resection. Radiographic imaging, perioperative and short-term outcomes were recorded. Surgical pathology specimens were analyzed for treatment response.

RESULTS

Three eligible patients with resectable PDAC received 4 months of NAC plus EUS-RFA. One month after NAC and EUS-RFA completion, all 3 patients underwent standard pancreaticoduodenectomy without complications. After a 6-week recovery, all patients completed 2 months of post-op adjuvant chemotherapy.

CONCLUSIONS

In our institutional experience, this treatment protocol appears safe as patients tolerated the combination of chemotherapy and ablation. Patients underwent pancreatic resection with uneventful recovery. This novel neoadjuvant approach may provide a more effective alternative to chemotherapy alone.

Minimally invasive treatment of early, good prognosis breast cancer-is this feasible?

Breast cancer screening programmes frequently detect early, good prognosis breast cancers with significant treatment burden for patients, and associated health-cost implications. Emerging evidence suggests a role for minimally invasive techniques in the management of these patients enabling many women to avoid surgical intervention. Minimally invasive techniques include vacuum-assisted excision, cryoablation, and radiofrequency ablation. We review published evidence in relation to the risks and benefits of each technique and discuss ongoing trials. Data to date are promising, and we predict a trend towards minimally invasive treatment for early, good-prognosis breast cancer as technical skills, suitability criteria, and follow-up protocols are established.

Assessing the relative effectiveness of various ultrasound-guided ablation techniques for treating benign thyroid nodules: A systematic review and network meta-analysis

BACKGROUND

Benign thyroid nodules (BTNs) represent a prevalent clinical challenge globally, with various ultrasound-guided ablation techniques developed for their management. Despite the availability of these methods, a comprehensive evaluation to identify the most effective technique remains absent. This study endeavors to bridge this knowledge gap through a network meta-analysis (NMA), aiming to enhance the understanding of the comparative effectiveness of different ultrasound-guided ablation methods in treating BTNs.

METHODS

We comprehensively searched PubMed, Embase, Cochrane, Web of Science, Ovid, SCOPUS, and ProQuest for studies involving 16 ablation methods, control groups, and head-to-head trials. NMA was utilized to evaluate methods based on the percentage change in nodule volume, symptom score, and cosmetic score. This study is registered in INPLASY (registration number 202260061).

RESULTS

Among 35 eligible studies involving 5655 patients, NMA indicated that RFA2 (radiofrequency ablation, 2 sessions) exhibited the best outcomes at 6 months for percentage change in BTN volume (SUCRA value 74.6), closely followed by RFA (SUCRA value 73.7). At 12 months, RFA was identified as the most effective (SUCRA value 81.3). Subgroup analysis showed RFA2 as the most effective for solid nodule volume reduction at 6 months (SUCRA value 75.6), and polidocanol ablation for cystic nodules (SUCRA value 66.5).

CONCLUSION

Various ablation methods are effective in treating BTNs, with RFA showing notable advantages. RFA with 2 sessions is particularly optimal for solid BTNs, while polidocanol ablation stands out for cystic nodules.

Comparison of Second-Generation Cryoballoon Ablation and Quantitative Radiofrequency Ablation Guided by Ablation Index for Atrial Fibrillation

We compared the efficacy and complication rates of quantitative radiofrequency ablation guided by ablation index (RFCA-AI) with those of second-generation cryoballoon ablation (CBA-2). Consecutive patients (n = 230) with symptomatic atrial fibrillation (AF) undergoing a first ablation CBA-2 (92 patients) or RFCA-AI (138 patients) procedure were enrolled in this study. The late recurrence rate in the CBA-2 group was higher than that in the RFCA-AI group (P = .012). Subgroup analysis showed the same result in patients with paroxysmal AF (PAF) (P = .039), but no difference was found in patients with persistent AF (P = .21). The average operation duration in the CBA-2 group (85 [75-99.5] minutes) was shorter than that in the RFCA-AI group (100 [84.5-120] minutes) (P < .0001), but the average exposure time (17.36(13.87-22.49) vs 5.49(4.00-8.24) minutes) in the CBA-2 group and X-ray dose (223.25(149.15-336.95) vs 109.15(80.75-168.7) mGym) were significantly longer than those in RFCA-AI group (P < .0001). Multivariate logistic regression analysis showed that left atrial diameter (LAD), early recurrence, and methods of ablation (cryoballoon ablation) were independent risk factors for late recurrence after AF ablation. Early recurrence of AF and LAD were independent risk factors for predicting late recurrence after AF ablation.

Radiofrequency atrial flutter and atrial fibrillation ablation in a patient with deep brain stimulation

Radiofrequency ablation for atrial fibrillation or atrial flutter is feasible in patients with deep brain stimulation but with extreme caution given the possibility of life-threatening complications.

Long-term Outcomes of Hepatic Resection Combined With Intraoperative Ablation Versus Hepatic Resection Alone for Multinodular Hepatocellular Carcinoma: Insights from a Single-center Study

BACKGROUND/AIM

The efficacy of combining hepatic resection (HR) with ablation therapy in treating multinodular hepatocellular carcinoma (mHCC) remains uncertain. This study aimed to compare the long-term survival outcomes of patients with mHCC undergoing HR combined with intraoperative ablation (HRA) versus those undergoing HR alone.

PATIENTS AND METHODS

A retrospective analysis was conducted on 296 patients diagnosed with early-stage [Barcelona Clinic Liver Cancer (BCLC)-A] or intermediate-stage (BCLC-B) mHCC who underwent initial HR. Patients were divided into two groups: those who received HRA (HRA group, n=159) and those who underwent HR alone (HR group, n=137). Propensity score (PS), estimated as the likelihood of undergoing HRA, was applied to adjust for between-group differences in baseline characteristics. Overall survival (OS) and relapse-free survival (RFS) were compared using Cox regression and Kaplan-Meier analyses.

RESULTS

There were no significant differences in survival between the HRA and HR groups, with 5-year OS and RFS rates of 47.7% versus 51.9% (p=0.837) and 17.0% versus 25.9% (p=0.094), respectively. After adjusting for PS, the differences remained non-significant (p=0.579 for OS and p=0.410 for RFS). Consistent results were also observed in PS-adjusted subgroup analysis stratified by factors such as BCLC stage, "Up-to-7" criteria, and Child-Pugh class.

CONCLUSION

HRA may offer comparable long-term efficacy to HR alone in mHCC, suggesting broader treatment options that challenge the guideline-based monotherapy.

Minimally-invasive conservative techniques in management of thyroid carcinoma: a narrative review

Increased diagnostic surveillance and technological innovation have considerably increased the number of thyroidectomies for carcinoma in the last decades. While thyroidectomy remains the first line of treatment, other minimally-invasive and conservative options to be applied in very selected cases have been proposed. The objective of this review is to illustrate the advantages and disadvantages of these techniques.

Idiopathic ventricular tachycardia detected after coronavirus disease 2019

We present a 23-year-old woman with depression and long COVID in whom a diagnosis of idiopathic ventricular tachycardia (VT) was made. Although the relationship between idiopathic VT and long COVID remains unknown, this is the first report of idiopathic VT detected in a patient with long COVID.

The anterior saphenous vein. Part 4. Clinical and technical considerations in treatment. Endorsed by the American Vein and Lymphatic Society, the American Venous Forum, and the International Union of Phlebology

BACKGROUND

The decision to treat a refluxing anterior saphenous vein (ASV) should be a clinical decision based on the assessment on the ASV's contribution to patient's signs and symptoms. Once the decision to treat has been made, there are anatomic, clinical, and technical considerations in treatment planning.

METHODS

Clinical scenarios were discussed by a panel of experts and common anatomic, clinical, and technical considerations were identified.

RESULTS

There are unique clinical considerations such as whether both the great saphenous vein (GSV) and ASV should be concomitantly treated, if a normal ASV should be treated when treating a refluxing GSV and when and how to treat the associated tributary varicose tributaries. Being aware of the anatomic, clinical, and technical considerations allows development of a treatment plan that optimizes long-term outcomes in patients with ASV reflux.

CONCLUSIONS

Ultimately the treatment plan should be tailored to address these types of variables in a patient-centered discussion.

Proton Beam Radiotherapy as a Curative Alternative to Radiofrequency Ablation for Newly Diagnosed Hepatocellular Carcinoma

BACKGROUND/AIM

This study aimed to compare the oncological outcomes of proton beam radiotherapy (PBT) with those of radiofrequency ablation (RFA) for newly diagnosed hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

This study included 323 patients who underwent PBT (n=40) or RFA (n=283) as a curative treatment for previously untreated HCC between October 2016 and June 2021. The primary endpoints were local progression and toxicity.

RESULTS

The median follow-up was 3.4 years (range=1.1-5.7 years). In terms of portal vein tumor thrombosis, tumor size, alpha-fetoprotein, and prothrombin-induced by vitamin K absence-II, the PBT group had significantly more severe tumor burdens than those of the RFA group (p<0.0001, p<0.0001, p=0.0004, and p<0.0001, respectively). No significant difference was observed in cumulative local progression rate (10.4% in PBT vs. 7.8% in RFA at 3-years, p=0.895). Grade 3 or higher toxicity was reported in only one patient (0.4%) after RFA. Multivariable analysis demonstrated that treatment modality was not a significant prognostic factor for local progression (hazard ratio=1.05; 95% confidence interval=0.32-3.48; p=0.934).

CONCLUSION

PBT demonstrated comparable local control with acceptable toxicity to RFA in newly diagnosed HCC. Therefore, PBT may be a valid alternative.

Radiofrequency ablation with or without transarterial chemoembolization for hepatocellular carcinoma meeting Milan criteria: a focus on tumor progression and recurrence patterns

Background/objective

The aim of this study was to evaluate tumor progression and recurrence patterns of radiofrequency ablation (RFA) with or without transarterial chemoembolization (TACE) for treating hepatocellular carcinoma (HCC) that meets Milan criteria.

Methods

This retrospective study included consecutive HCC patients meeting Milan criteria who underwent percutaneous RFA with or without TACE as initial treatment at a tertiary academic center between December 2017 and 2022. Technical success rate, local recurrence-free survival (LRFS), progression-free survival (PFS) and recurrence patterns were recorded.

Results

A total of 135 HCC patients (109 male [80.7%]) with a mean age of 62 years and 147 target lesions were retrospectively enrolled. The technical success rate was 99.3%. The median LRFS was 60 months, and the cumulative 1-, 3-, and 5-year LRFS were 88.9%, 70.1%, and 30.0%, respectively. Additionally, the median PFS was 23 months, with cumulative 1-, 3-, and 5-year PFS of 74%, 30%, and 0%, respectively. Multivariate analysis confirmed that age > 60, alpha-fetoprotein (AFP) (> 10), and albumin were associated with PFS (2.34, p = 0.004; 1.96, p = 0.021; 0.94, p = 0.007, respectively). Six recurrence patterns were identified: local tumor progression (LTP) alone (n = 15, 25.0%), intrahepatic distant recurrence (IDR) alone (n = 34, 56.7%), extrahepatic recurrence (ER) alone (n = 2, 3.3%), IDR + ER (n = 2, 3.3%), LTP + IDR (n = 5, 8.8%), and LTP + IDR + ER (n = 2, 3.3%). IDR occurred most frequently as a sign of good local treatment.

Conclusions

RFA in combination with TACE does not appear to provide an advantage over RFA alone in improving tumor progression in patients with HCC meeting the Milan criteria. However, further prospective studies are needed to confirm these findings and to determine the optimal treatment approach for this patient population.

Cryoballoon pulmonary vein isolation versus radiofrequency ablation of the pulmonary veins and left atrial posterior wall: Patient-reported outcomes

BACKGROUND

Data are lacking on patient-reported outcomes (PRO) following cryoballoon ablation (CBA) versus radiofrequency ablation (RFA). We sought to evaluate QoL and clinical outcomes of cryoballoon pulmonary vein isolation only (CRYO-PVI-ONLY) versus RFA with PVI and posterior wall isolation (RF-PVI+PWI) in a large prospective PRO registry.

METHODS

Patients who underwent AF ablation (2013-2016) at our institution were enrolled in an automated, prospectively maintained PRO registry. CRYO-PVI-ONLY patients were matched (1:1) with RF-PVI+PWI patients based on age, gender, and type of AF (paroxysmal vs. persistent). QoL and clinical outcomes were assessed using PRO surveys at baseline and at 1-year. The atrial fibrillation symptom severity scale (AFSSS) was the measure for QoL. Additionally, we assessed patient-reported clinical improvement, arrhythmia recurrence, and AF burden (as indicated by AF frequency and duration scores).

RESULTS

A total of 296 patients were included (148 in each group, 72% paroxysmal). By PRO, a significant improvement in QoL was observed in the overall study population and was comparable between CRYO-PVI-ONLY and RF-PVI+PWI (baseline median AFSSS of 11.5 and 11; reduced to 2 and 4 at 1 year, respectively; p = 0.44). Similarly, the proportion of patients who reported improvement in their overall QoL and AF related symptoms was high and similar between the study groups [92% (CRYO-PVI-ONLY) vs. 92.8% (RF-PVI+PWI); p = 0.88]. Arrhythmia recurrence was significantly more common in the CRYO-PVI-ONLY group (39.7%) compared to RF-PVI+PWI (27.7 %); p = 0.03. Comparable results were observed in paroxysmal and persistent AF.

CONCLUSION

CRYO-PVI-ONLY and RF-PVI+PWI resulted in comparable improvements in patient reported outcomes including QoL and AF burden; with RF-PVI+PWI being more effective at reducing recurrences.

Emerging Role of Gallium-68 DOTANOC PET/CT Guided Radiofrequency Ablation in the Treatment of Tumor-induced Osteomalacia

Tumor-induced osteomalacia (TIO) is a rare acquired form of hypophosphatemia that can be cured when the tumor responsible is completely removed. These tumors can be small and located in anatomically challenging areas, rendering surgery both risky and extensive. Radiofrequency ablation (RFA) has been explored as an effective treatment option for such tumors. We present a case of a 35-year-old man exhibiting clinical and biochemical features consistent with TIO. The culprit lesion was not detectable on the whole-body computed tomography (CT) scan. Gallium (Ga-68) DOTANOC positron emission tomography (PET)/CT showed increased uptake in the left acetabulum and magnetic resonance imaging (MRI) confirmed the location of the tumor. Given the risky anatomical location, we opted for less-invasive RFA. Following an unsuccessful attempt at CT-guided RFA of the lesion, we used real-time Ga-68 DOTANOC PET/CT guidance for precise imaging during the ablation procedure. Our patient achieved complete remission both clinically and biochemically after RFA. This response was also evident by the absence of tracer uptake in follow-up imaging. In conclusion, DOTANOC PET/CT-guided RFA can serve as a safe and effective treatment for patients with tumors causing TIO. This modality proves valuable when surgical resection is not a viable option.

Challenges of atrial fibrillation and atrial flutter ablation in patients with pectus excavatum

Atrial fibrillation (AF) may be associated with chest wall abnormalities such as pectus excavatum (PE). Pulmonary vein isolation (PVI) has proven to be a useful strategy for radiofrequency catheter ablation (RFCA) of AF. However, the presence of chest wall abnormalities, such as pectus excavatum, imposes certain challenges during ablation due to the anatomic distortion that it causes. We highlight these challenges during ablation in this three-patient case series.

Shoulder terminal sensory articular nerve radiofrequency ablation for non-surgical refractory shoulder pain due to rotator cuff pathology and osteoarthritis: A technical note

BACKGROUND

Given the high prevalence of chronic shoulder pain and encouraging early results of terminal sensory articular branch (TSAB) radiofrequency ablation to treat shoulder pain, research is warranted to refine the procedural technique based on updated neuroanatomical knowledge with the goal of further improving patient outcomes.

OBJECTIVE

We describe an updated radiofrequency ablation protocol that accounts for varied locations of the TSABs of suprascapular, axillary, subscapular and lateral pectoral nerves within individual patients.

DESIGN

Technical note.

METHODS

Cadaveric studies delineating the sensory innervation of the shoulder joint were reviewed, and a more comprehensive radiofrequency ablation (RFA) protocol is proposed relative to historical descriptions.

CONCLUSIONS

Based on neuroanatomical dissections of the shoulder joint, the proposed RFA protocol will provide a safe means of more complete sensory denervation and potentially improve clinical outcomes compared to historical descriptions, which must be confirmed in prospective studies.

Application of Deep Learning for Real-Time Ablation Zone Measurement in Ultrasound Imaging

BACKGROUND

The accurate delineation of ablation zones (AZs) is crucial for assessing radiofrequency ablation (RFA) therapy's efficacy. Manual measurement, the current standard, is subject to variability and potential inaccuracies.

AIM

This study aims to assess the effectiveness of Artificial Intelligence (AI) in automating AZ measurements in ultrasound images and compare its accuracy with manual measurements in ultrasound images.

METHODS

An in vitro study was conducted using chicken breast and liver samples subjected to bipolar RFA. Ultrasound images were captured every 15 s, with the AI model Mask2Former trained for AZ segmentation. The measurements were compared across all methods, focusing on short-axis (SA) metrics.

RESULTS

We performed 308 RFA procedures, generating 7275 ultrasound images across liver and chicken breast tissues. Manual and AI measurement comparisons for ablation zone diameters revealed no significant differences, with correlation coefficients exceeding 0.96 in both tissues (p < 0.001). Bland-Altman plots and a Deming regression analysis demonstrated a very close alignment between AI predictions and manual measurements, with the average difference between the two methods being -0.259 and -0.243 mm, for bovine liver and chicken breast tissue, respectively.

CONCLUSION

The study validates the Mask2Former model as a promising tool for automating AZ measurement in RFA research, offering a significant step towards reducing manual measurement variability.

Case Report: Pulsed field ablation for epicardial right-sided accessory pathway

We present a case of a 32-year-old male with a history of palpitations and preexcitation on ECG who underwent altogether four failed catheter ablations using different approaches in the two other electrophysiology centers within two years. ECG showed overt preexcitation with a positive delta wave in lead I and negative in leads V1-V3, suggesting a right free wall accessory pathway. During the electrophysiological study, the accessory pathway was localized on the free lateral wall. However, the electrograms and mapping during atrial and ventricular pacing suggested the presence of true epicardial accessory pathway. Repeated radiofrequency energy delivery with the support of the steerable sheath and excellent contact (as assessed by intracardiac echocardiography) at the earliest ventricular activation was not successful. Therefore, the Farawave catheter (Boston Scientific, Inc) was used, and a flower configuration with the intention to cover the entire atrial attachment of the pathway during ventricular pacing was selected. Application of pulsed field resulted in interruption of accessory pathway conduction. An electrophysiological study one year later confirmed the persistent effect of ablation. This case illustrates the potential utility of pulsed field energy for the ablation of atrial insertion of the accessory pathway with an epicardial course. Such an approach can avoid epicardial mapping and access and may improve the safety of the procedure.

Efficacy of Shensong Yangxin capsule combined with dronedarone in paroxysmal atrial fibrillation after ablation

OBJECTIVE

To investigate whether postoperative administration of Shensong Yangxin capsules (SSYX) and dronedarone for atrial fibrillation (AF) can reduce the recurrence of paroxysmal AF after radiofrequency ablation, thus providing a more optimal choice of antiarrhythmic medication during the blank period.

METHODS

We included 120 patients with paroxysmal AF who underwent radiofrequency ablation at our hospital between July 2020 and July 2022. They underwent routine circumferential pulmonary vein ablation and, subsequently, left and right atrial pressure monitoring to assess sinoatrial node recovery time under burst 400/300 ms stimulation. Postoperatively, the patients were randomly divided into 2 groups (60 patients each). The control group was administered dronedarone orally for 3 months and the study group was treated with SSYX combined with dronedarone. This study aimed to compare differences in clinical efficacy of the treatment between the 2 groups.

RESULTS

The left and right atrial pressures in both groups were higher than those in the preoperative period (P < .05), with no statistically significant differences between the 2 groups (P > .05). Sinoatrial node recovery time under burst 400/300 ms stimulation showed no statistical difference between the 2 groups (P > .05). At 3 months and 1 year postoperatively, the AFEQT scale scores for both groups were lower than those before treatment (P < .05), with the study group scoring lower than the control group at 3 months (P < .05). However, no statistically significant difference was observed between the 2 groups at 1 year postoperatively (P > .05). At 3 months postoperatively, the sinus rhythm maintenance rate and heart rate were higher in the intervention group than in the control group (P < .05); however, these differences between the 2 groups were not statistically significant at 1 year postoperatively (P > .05).

CONCLUSION SUBSECTIONS

The combination of SSYX and dronedarone could effectively reduce the early recurrence of paroxysmal AF after radiofrequency ablation, increase heart rate, and improve the quality of life.

Post-surgical Persistent Hyperparathyroidism Successfully Treated with Parathyroid Radiofrequency Ablation: A Case Report

BACKGROUND

Currently, parathyroidectomy is the standard treatment for Primary Hyperparathyroidism (PHPT). Surgical treatment is often effective, although not free of complications and relapses. Minimally invasive techniques, such as Microwave Ablation (MWA) and Radiofrequency Ablation (RFA), are an alternative to surgery in selected patients. We have, herein, reported on the successful use of RFA in a patient with post-surgical persistent hyperparathyroidism.

CASE PRESENTATION

A 54-year-old woman was referred to our Center for mild hypercalcemia with exams revealing Primary Hyperparathyroidism (PHPT). Neck ultrasound and Technetium- 99 Methoxy-isobutyl-isonitrile (99mTc-MIBI) scintigraphy scanning revealed a suspicious right parathyroid hyperplasia/adenoma. She underwent parathyroidectomy and histological examination showed a parathyroid nodular hyperplasia. During the follow-up, she suffered from persistent hyperparathyroidism due to the treatment of left parathyroid hypoplasia with RFA. Blood tests after the procedure showed the remission of the disease 7 months post-treatment.

CONCLUSION

A minimally invasive technique for PHPT may represent a valid alternative to surgery, especially in patients with an elevated surgery-related risk. More studies are necessary to investigate the benefit of RFA as a first-line treatment in PHPT.

Treatment of Warthin's Tumors of the Parotid Gland With Radiofrequency Ablation: A Systematic Review of the Current Literature

Objective: Warthin's tumors of the parotid gland can be safely observed. Definitive treatment usually requires parotidectomy under general anesthesia. The decision to operate on Warthin's tumors of the parotid gland can be complicated in patients who wish to avoid risks of surgery and general anesthesia. This systematic review explores the potential of radiofrequency ablation (RFA) as a minimally invasive alternative. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model was used to collect 3 relevant studies that focused on RFA treatment for Warthin's tumors. The cumulative averages for tumor size and cosmetic scores were then quantified for patients with Warthin's tumors who underwent RFA therapy. The PRISMA systematic review method was employed to the PubMed and EMBASE databases. The comprehensive search term "Warthin Tumor Treatment" yielded 1299 articles from the years 1955 to 2023, 3 of which met inclusion criteria and were then selected. Results: The 3 quantitative studies collectively assessed 37 patients with Warthin's tumors treated with RFA. Patients experienced an average tumor size reduction of 85.03% at 12 months post-RFA. There were minimal complications associated with RFA in these patients. Conclusion: This study suggests that RFA is an alternative to parotidectomy for the symptomatic treatment of Warthin's tumors. RFA procedures demonstrated substantial tumor size reduction with few complications. However, further meta-analysis and comparison with alternative treatments is warranted to establish RFA's role in treatment of Warthin's tumors. The study is limited by its reliance on only 2 databases and a lack of comprehensive examination of different RFA settings.

Perioperative and Oncological Outcomes of Percutaneous Radiofrequency Ablation versus Partial Nephrectomy for cT1a Renal Cancers: A Retrospective Study on Groups with Similar Clinical Characteristics

Over the recent years, progress in imaging techniques has led to an increased detection of kidney tumours, including small renal masses. While surgery is still the standard of care, there is a growing interest in minimally invasive methods. Ultrasound (US)-guided percutaneous ablation is particularly attractive because it is a safe and relatively simple procedure. In this study, we investigated the results of US-guided percutaneous radiofrequency ablation (RFA) and partial nephrectomy (PN) in the treatment of cT1a renal cancers. Between August 2016 and February 2022, 271 patients with renal tumours underwent percutaneous RFA as initial treatment in our institution. In the same period, 396 patients with renal tumours underwent surgical tumour excision. For the purpose of this study, only patients with confirmed renal cancer with matched age and tumour characteristics (size, location) were selected for both groups. Thus, a group of 44 PN patients and 41 RFA patients were formed with the same qualification criteria for both groups. Parameters such as procedure length, blood loss, hospital stay, analgesics used, and pre- and post-procedural serum creatinine were compared between these groups. Patients followed up with contrast-enhanced CT. There was no significant difference in age, tumour size, tumour location, and creatinine levels between these groups. All procedures were generally well tolerated. During a median follow-up of 28 months, two cases of recurrence/residual disease were found in each group. The overall survival was 100% in both groups, and all patients were disease-free at the end of observation. Percutaneous RFA was associated with a significantly shorter procedure length and hospital stay, lower blood loss, and lower analgesics used than PN. In the selected group of renal cancer patients, US-guided percutaneous RFA was associated with a shorter hospital stay, less analgesics used, and a shorter procedure length than PN, without differences in the oncological results or kidney function.

Radiofrequency for chronic lumbosacral and cervical pain: Results of a consensus study using the RAND/UCLA appropriateness method

BACKGROUND

Despite the routine use of radiofrequency (RF) for the treatment of chronic pain in the lumbosacral and cervical region, there remains uncertainty on the most appropriate patient selection criteria. This study aimed to develop appropriateness criteria for RF in relation to relevant patient characteristics, considering RF ablation (RFA) for the treatment of chronic axial pain and pulsed RF (PRF) for the treatment of chronic radicular pain.

METHODS

The RAND/UCLA Appropriateness Method (RUAM) was used to explore the opinions of a multidisciplinary European panel on the appropriateness of RFA and PRF for a variety of clinical scenarios. Depending on the type of pain (axial or radicular), the expert panel rated the appropriateness of RFA and PRF for a total of 219 clinical scenarios.

RESULTS

For axial pain in the lumbosacral or cervical region, appropriateness of RFA was determined by the dominant pain trigger and location of tenderness on palpation with higher appropriateness scores if these variables were suggestive of the diagnosis of facet or sacroiliac joint pain. Although the opinions on the appropriateness of PRF for lumbosacral and cervical radicular pain were fairly dispersed, there was agreement that PRF is an appropriate option for well-selected patients with radicular pain due to herniated disc or foraminal stenosis, particularly in the absence of motor deficits. The panel outcomes were embedded in an educational e-health tool that also covers the psychosocial aspects of chronic pain, providing integrated recommendations on the appropriate use of (P)RF interventions for the treatment of chronic axial and radicular pain in the lumbosacral and cervical region.

CONCLUSIONS

A multidisciplinary European expert panel established patient-specific recommendations that may support the (pre)selection of patients with chronic axial and radicular pain in the lumbosacral and cervical region for either RFA or PRF (accessible via https://rftool.org). Future studies should validate these recommendations by determining their predictive value for the outcomes of (P)RF interventions.

Transarterial chemoembolization combined with radiofrequency ablation for medium and large hepatocellular carcinoma: insufficient ablation is associated with intrahepatic distant metastasis and extrahepatic metastasis

Purpose

To compare the prognosis of complete and insufficient ablation of transarterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) in treating medium and large hepatocellular carcinoma (HCC) and to explore the differences in recurrence patterns between the two groups.

Patients and methods

Patients´ medical records and imaging data of patients with confirmed HCC from January 2014 to January 2022 were collected. These patients were divided into 2 groups: complete ablation (n=172) and insufficient ablation (n=171). Overall survival (OS) and progression-free survival (PFS) were estimated by the Kaplan-Meier curve and the log-rank test was used to compared. Fisher's exact test was used to compare recurrence patterns between the two groups.

Results

The median OS time was 72.8 months (95%CI:69.5-76.1) and 62.0 months (95%CI: 55.3-68.7) in the complete and insufficient ablation groups, respectively. The median PFS time in the complete ablation group was 67.8 months (95% CI: 65.2-70.4) and 38.6 months (95%CI: 29.8-47.4) in the insufficient ablation group. The OS and PFS rates of the complete ablation group were significantly better than those of the insufficient ablation group (P<0.001). In the complete ablation group, 25(41%) patients experienced local tumor progression(LTP), 36(59%) experienced intrahepatic distant progression(IDP), and 0(0%) experienced extrahepatic progression (EP). In the insufficient ablation group, 51 (32.1%) patients experienced LTP, 96 (60.4%) experienced IDP, and 12 (7.5%) experienced EP. The progression patterns of the two groups were statistically significant (P=0.039).

Conclusion

Insufficient ablation indicates a poor survival outcome of TACE combined with RFA for medium and large HCC and can promote intrahepatic distant and extrahepatic metastasis.

Novel self-expandable stent-based endobiliary radiofrequency ablation for unresectable malignant biliary obstruction

BACKGROUND AND AIMS

Endobiliary radiofrequency ablation (RFA) is an emerging endoscopic palliative adjunctive therapy used for the local treatment of unresectable malignant biliary obstruction (MBO). However, irregular ablation ranges caused by insufficient electrode-to-bile duct contact pose a significant obstacle. The aim was to investigate the feasibility of a self-expandable stent (SES)-based electrode with a customized RFA generator in the porcine liver and common bile duct (CBD).

METHODS

A SES-RFA system with polarity-switching was developed to perform endobiliary RFA. The ablation ranges of 20 ablation protocols were evaluated to validate the feasibility of the newly developed RFA system in the porcine liver. Nine of the 20 ablation protocols were selected for evaluation in the porcine CBD with cholangiography, endoscopy, and histological and immunohistochemical analysis.

RESULTS

The SES-RFA system with polarity-switching was successfully constructed and demonstrated high accuracy and reproducibility. The ablation area was clearly identified between the two SESs. The ablation ranges and degree of mucosal damage including TUNEL- and HSP70-positive depositions increased proportionally with ablation protocols in the porcine liver and CBD (all P < .05). Ablation length and depth linearly increased with ablation protocols from 8.74 ± 0.25 to 31.25 ± 0.67 mm and 1.61 ± 0.09 to 11.94 ± 0.44 mm, respectively.

CONCLUSIONS

The SES-RFA system with polarity-switching between electrodes provided an even circumferential area of ablation and enhanced ablation depth between the electrodes. This novel endobiliary RFA system is a promising modality for local ablation in patients with unresectable MBO.

A case report of atrial septal puncture "mistakenly" penetrated the aorta during left bypass radiofrequency ablation

INTRODUCTION

Transseptal punctures (TSPs) are widely used in left atrium and left ventricle surgery. Accidental puncture of the puncture needle into the aorta is a rare complication that is rarely reported but has serious consequences. The appropriate management of this complication remains unclear.

PATIENT CONCERNS

This report describes a case of a male with the chief complaint: paroxysmal palpitation for 1 year, aggravated for 1 month.

DIAGNOSIS

The electrophysiological diagnosis was atrioventricular reentrant tachycardia caused by left-side bypass.

INTERVENTIONS

Radiofrequency ablation of the heart was a necessary treatment and a TSP operation was needed, in which a puncture was mistakenly believed to have entered the aorta, a series of measures were taken urgently. Although the surgical procedure in this case was a false alarm, we still initiated a series of emergency plans. Emergency measures to address the complications were effectively implemented, and the emergency measures were promptly terminated after it was clear that complications had been misjudged.

OUTCOMES

At last, it was confirmed that the angiogram was a pulmonary artery image, not an aorta image. Then the atrial septal puncture operation was successfully completed, and under the guidance of the Carto system, the ablation was successfully completed. Postoperative fluoroscopy showed no complications, such as pericardial effusion. After 2 years of follow-up, there was no reoccurrence of tachycardia, and there were no complications. It is crucial that emergency procedures are terminated in a timely manner after a clear miscarriage of performance. Although accidental puncture into the aorta is urgent and serious, performing a blockage or even thoracotomy in an emergency if complications are not clearly confirmed can cause further damage to the patient and would be a definitively wrong strategy.

CONCLUSION

Strict and standardized TSP operations can avoid complications. Correct judgment of the authenticity of complications is crucial, and remedial measures that may cause further damage should not be blindly adopted. The retention of the aortic guide wire can provide convenient access for further differential diagnosis and remedial treatment.

Association between proactive esophageal cooling and increased lab throughput

INTRODUCTION

Proactive esophageal cooling has been FDA cleared to reduce the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures. Data suggest that procedure times for RF pulmonary vein isolation (PVI) also decrease when proactive esophageal cooling is employed instead of luminal esophageal temperature (LET) monitoring. Reduced procedure times may allow increased electrophysiology (EP) lab throughput. We aimed to quantify the change in EP lab throughput of PVI cases after the introduction of proactive esophageal cooling.

METHODS

EP lab throughput data were obtained from three EP groups. We then compared EP lab throughput over equal time frames at each site before (pre-adoption) and after (post-adoption) the adoption of proactive esophageal cooling.

RESULTS

Over the time frame of the study, a total of 2498 PVIs were performed over a combined 74 months, with cooling adopted in September 2021, November 2021, and March 2022 at each respective site. In the pre-adoption time frame, 1026 PVIs were performed using a combination of LET monitoring with the addition of esophageal deviation when deemed necessary by the operator. In the post-adoption time frame, 1472 PVIs were performed using exclusively proactive esophageal cooling, representing a mean 43% increase in throughput (p < .0001), despite the loss of two operators during the post-adoption time frame.

CONCLUSION

Adoption of proactive esophageal cooling during PVI ablation procedures is associated with a significant increase in EP lab throughput, even after a reduction in total number of operating physicians in the post-adoption group.

Thyroid nodule rupture after radiofrequency ablation: case report and literature review

Purpose

Radiofrequency ablation (RFA) is an effective and safe modality for the treatment of thyroid nodules. Nodule rupture is a major complication of RFA. There is little known on the natural history of nodule rupture due to a lack of clinical experience and no consensus on its management. A comprehensive review of nodule rupture presentation, diagnosis, and management is needed.

Methods

We report a case of nodule rupture and conduct a literature review. A total of 33 patients experiencing nodule rupture after RFA were included, and their clinical presentation, management, and outcomes were collected and analyzed.

Results

Nodule rupture presents with acute swelling (90.3%) and pain (77.4%) within 7 months of RFA procedure, most commonly due to disruption of the anterior thyroid capsule (87%), and can be diagnosed with ultrasonography. Most ruptures can be managed conservatively, exemplified by our reported case. There are no reported cases of long-term sequalae.

Conclusion

Nodule rupture is the second most common major complication of RFA. Based on the available evidence, we propose a treatment algorithm for nodule rupture and recommendations for future data collection to address gaps in our understanding of rupture etiology and effective management.

5. Sacroiliac joint pain

INTRODUCTION

Sacroiliac (SI) joint pain is defined as pain localized in the anatomical region of the SI joint. The reported prevalence of SI joint pain among patients with mechanical low back pain varies between 15% and 30%.

METHODS

In this narrative review, the literature on the diagnosis and treatment of SI joint pain was updated and summarized.

RESULTS

Patient's history provides clues on the source of pain. The specificity and sensitivity of provocative maneuvers are relatively high when three or more tests are positive, though recent studies have questioned the predictive value of single or even batteries of provocative tests. Medical imaging is indicated only to rule out red flags for potentially serious conditions. The diagnostic value of SI joint infiltration with local anesthetic remains controversial due to the potential for false-positive and false-negative results. Treatment of SI joint pain ideally consists of a multidisciplinary approach that includes conservative measures as first-line therapies (eg, pharmacological treatment, cognitive-behavioral therapy, manual medicine, exercise therapy and rehabilitation treatment, and if necessary, psychological support). Intra- and extra-articular corticosteroid injections have been documented to produce pain relief for over 3 months in some people. Radiofrequency ablation (RFA) of the L5 dorsal ramus and S1-3 (or 4) lateral branches has been shown to be efficacious in numerous studies, with extensive lesioning strategies (eg, cooled RFA) demonstrating the strongest evidence. The reported rate of complications for SI joint treatments is low.

CONCLUSIONS

SI joint pain should ideally be managed in a multidisciplinary and multimodal manner. When conservative treatment fails, corticosteroid injections and radiofrequency treatment can be considered.

Surpoint algorithm for improved guidance of ablation for ventricular tachycardia (SURFIRE-VT): A pilot study

INTRODUCTION

The utility of ablation index (AI) to guide ventricular tachycardia (VT) ablation in patients with structural heart disease is unknown. The aim of this study was to assess procedural characteristics and clinical outcomes achieved using AI-guided strategy (target value 550) or conventional non-AI-guided parameters in patients undergoing scar-related VT ablation.

METHODS

Consecutive patients (n = 103) undergoing initial VT ablation at a single center from 2017 to 2022 were evaluated. Patient groups were 1:1 propensity-matched for baseline characteristics. Single lesion characteristics for all 4707 lesions in the matched cohort (n = 74) were analyzed. The impact of ablation characteristics was assessed by linear regression and clinical outcomes were evaluated by Cox proportional hazard model.

RESULTS

After propensity-matching, baseline characteristics were well-balanced between AI (n = 37) and non-AI (n = 37) groups. Lesion sets were similar (scar homogenization [41% vs. 27%; p = .34], scar dechanneling [19% vs. 8%; p = .18], core isolation [5% vs. 11%; p = .4], linear and elimination late potentials/local abnormal ventricular activities [35% vs. 44%; p = .48], epicardial mapping/ablation [11% vs. 14%; p = .73]). AI-guided strategy had 21% lower procedure duration (-47.27 min, 95% confidence interval [CI] [-81.613, -12.928]; p = .008), 49% lower radiofrequency time per lesion (-13.707 s, 95% CI [-17.86, -9.555]; p < .001), 21% lower volume of fluid administered (1664 cc [1127, 2209] vs. 2126 cc [1750, 2593]; p = .005). Total radiofrequency duration (-339 s [-24%], 95%CI [-776, 62]; p = .09) and steam pops (-155.6%, 95% CI [19.8%, -330.9%]; p = .08) were nonsignificantly lower in the AI group. Acute procedural success (95% vs. 89%; p = .7) and VT recurrence (0.97, 95% CI [0.42-2.2]; p = .93) were similar for both groups. Lesion analysis (n = 4707) demonstrated a plateau in the magnitude of impedance drops once reaching an AI of 550-600.

CONCLUSION

In this pilot study, an AI-guided ablation strategy for scar-related VT resulted in shorter procedure time and average radiofrequency time per lesion with similar acute procedural and intermediate-term clinical outcomes to a non-AI-guided approach utilizing traditional ablation parameters.

Acute myocardial infarction following radiofrequency catheter ablation in a child: a case report on the mechanism of coronary artery occlusion assessed by cardiovascular imaging

Background

Radiofrequency ablation is a common treatment for atrioventricular nodal re-entrant tachycardia, even in paediatric patients weighing ≥15 kg, where outcomes are similar to those in adults. However, reports of acute coronary artery occlusion after radiofrequency ablation for atrioventricular nodal re-entrant tachycardia are rare.

Case summary

An 11-year-old girl with symptomatic atrioventricular nodal re-entrant tachycardia refractory to drug treatment underwent radiofrequency ablation. During the procedure, ST elevation was observed, and coronary angiography revealed occlusion of the right coronary artery at the segment 4 atrioventricular branch. Intravascular ultrasonography showed a narrowed lumen and an abnormal area of low echogenicity in the adjacent myocardium. After dilation with a 1.5 mm diameter balloon, blood flow was successfully restored. Follow-up coronary computed tomography angiography revealed residual stenosis in the right coronary artery at the segment 4 atrioventricular branch; however, blood flow to the distal occlusion was preserved. The patient was discharged without further complications.

Discussion

To the best of our knowledge, this is the first report of coronary artery occlusion following radiofrequency ablation for atrioventricular nodal re-entrant tachycardia, evaluated using intravascular ultrasonography and coronary computed tomography angiography. Based on the imaging findings, direct thermal injury was considered the cause of occlusion.

A Transformer-Based microvascular invasion classifier enhances prognostic stratification in HCC following radiofrequency ablation

BACKGROUND & AIMS

We aimed to develop a Transformer-based deep learning (DL) network for prognostic stratification in hepatocellular carcinoma (HCC) patients undergoing RFA.

METHODS

A Swin Transformer DL network was trained to establish associations between magnetic resonance imaging (MRI) datasets and the ground truth of microvascular invasion (MVI) based on 696 surgical resection (SR) patients with solitary HCC ≤3 cm, and was validated in an external cohort (n = 180). The multiphase MRI-based DL risk outputs using an optimal threshold of .5 was employed as a MVI classifier for prognosis stratification in the RFA cohort (n = 180).

RESULTS

Over 90% of all enrolled patients exhibited hepatitis B virus infection. Liver cirrhosis was significantly more prevalent in the RFA cohort compared to the SR cohort (72.2% vs. 44.1%, p < .001). The MVI risk outputs exhibited good performance (area under the curve values = .938 and .883) for predicting MVI in the training and validation cohort, respectively. The RFA patients at high risk of MVI classified by the MVI classifier demonstrated significantly lower recurrence-free survival (RFS) and overall survival rates at 1, 3 and 5 years compared to those classified as low risk (p < .001). Multivariate cox regression modelling of a-fetoprotein > 20 ng/mL [hazard ratio (HR) = 1.53; 95% confidence interval (95% CI): 1.02-2.33, p = .047], high risk of MVI (HR = 3.76; 95% CI: 2.40-5.88, p < .001) and unfavourable tumour location (HR = 2.15; 95% CI: 1.40-3.29, p = .001) yielded a c-index of .731 (bootstrapped 95% CI: .667-.778) for evaluating RFS after RFA. Among the three risk factors, MVI was the most powerful predictor for intrahepatic distance recurrence.

CONCLUSIONS

The proposed MVI classifier can serve as a valuable imaging biomarker for prognostic stratification in early-stage HCC patients undergoing RFA.

New radiofrequency ablation procedure for selective reduction in complicated monochorionic twin or triplet pregnancy using multistep, incremental expansion technique

OBJECTIVE

Radiofrequency ablation (RFA) is the preferred approach for selective reduction in complex monochorionic (MC) multiple pregnancies owing to the ease of operation and minimal invasiveness. To optimize the RFA technique and reduce the risk of adverse pregnancy outcome resulting from the heat-sink effect of RFA therapy, we used an innovative RFA method, in which an electrode needle was expanded incrementally and stepwise. This study aimed to assess the efficacy and safety profile of this novel multistep incremental expansion RFA method for selective fetal reduction in MC twin and triplet pregnancies.

METHODS

This was a single-center retrospective cohort study of all MC multiple pregnancies undergoing RFA between March 2016 and October 2022 at our center. The multistep RFA technique involved the use of an expandable needle, which was gradually expanded during the RFA procedure until cessation of umbilical cord blood flow was achieved. The needle used for the single-step RFA method was fully extended from the start of treatment.

RESULTS

In total, 132 MC multiple pregnancies underwent selective reduction using RFA, including 50 cases undergoing multistep RFA and 82 cases undergoing single-step RFA. The overall survival rates were not significantly different between the multistep and single-step RFA groups (81.1% vs 72.3%; P = 0.234). Similarly, the rates of preterm prelabor rupture of the membranes within 2 weeks after RFA, procedure-related complications, spontaneous preterm delivery and pathological findings on cranial ultrasound, as well as gestational age at delivery and birth weight, did not differ between the two groups. However, there was a trend towards a prolonged procedure-to-delivery interval following multistep RFA compared with single-step RFA (median, 109 vs 99 days; P = 0.377). Moreover, the fetal loss rate within 2 weeks after RFA in the multistep RFA group was significantly lower than that in the single-step RFA group (10.0% vs 24.4%; P = 0.041). The median ablation time was shorter (5.3 vs 7.8 min; P < 0.001) and the median ablation energy was lower (10.2 vs 18.0 kJ; P < 0.001) in multistep compared with single-step RFA. There were no significant differences in neonatal outcomes following multistep vs single-step RFA.

CONCLUSIONS

Overall survival rates were similar between the two RFA methods. However, the multistep RFA technique was associated with a lower risk of fetal loss within 2 weeks after RFA. The multistep RFA technique required significantly less ablation energy and a shorter ablation time compared with single-step RFA in selective fetal reduction of MC twin and triplet pregnancies. Additionally, there was a trend towards a prolonged procedure-to-delivery interval with the multistep RFA technique. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

In Vivo Findings of a Novel Focal Ablation Catheter: Focused Electric Field Catheter Tip

Current catheter designs used for radiofrequency (RF) in cardiac tissue achieve limited ablation depth as lesion size is driven heavily by resistive heating at the tissue surface. A catheter with a truncated, dome-shaped tip with a toroidal surface designed for focal RF ablation was recently described. This in vivo study compares lesion characteristics between a second-generation focused electric field (FEF) catheter vs a standard irrigated catheter using RF energy in a beating heart model. We performed in vivo ablations using RF energy with the FEF ablation catheter tip (Focused Therapeutics) and an irrigated Blazer catheter (Boston Scientific) under identical power, duration, and irrigation rates. In addition, RF dosing at high power and duration was examined using the FEF catheter. Intracardiac echocardiography was used to evaluate steam pops and catheter tip angle relative to the tissue surface. Studies were terminal and lesion size was measured following 2,3,5-triphenyltetrazolium chloride staining. Ablations were performed in 6 swine (FEF, n = 31; control, n = 8). FEF ablation lesions (n = 7) were deeper (15.6 ± 2.6 mm vs 7.5 ± 1.9 mm; P < 0.001) and wider (18.4 ± 2.9 mm vs 12.6 ± 2.4 mm; P < 0.001) than lesions delivered with the control irrigated catheter (n = 8) under the same parameters. Thirty-two percent (n = 10 of 31) of lesions delivered from the left ventricle endocardial surface using the FEF catheter were transmural. No steam pops were observed with delivery of FEF lesions (n = 31). The angle of incidence did not significantly affect FEF lesion size. In this in vivo preclinical study, the FEF catheter, which provides focused energy delivery, resulted in significantly larger lesions than the irrigated control catheter without steam pops. Approximately one-third of ablations with the FEF catheter delivered from the endocardial left ventricular surface resulted in transmural lesions.

Enhancing precision in lung tumor ablation through innovations in CT-guided technique and angle control

BACKGROUND

This retrospective study aimed to evaluate the precision and safety outcomes of image-guided lung percutaneous thermal ablation (LPTA) methods, focusing on radiofrequency ablation (RFA) and microwave ablation (MWA). The study utilized an innovative angle reference guide to facilitate these techniques in the treatment of lung tumors.

METHODS

This study included individuals undergoing LPTA with the assistance of laser angle guide assembly (LAGA) at our hospital between April 2011 and March 2021. We analyzed patient demographics, tumor characteristics, procedure details, and complications. Logistic regressions were employed to assess risk factors associated with complications.

RESULTS

A total of 202 patients underwent ablation for 375 lung tumors across 275 sessions involving 495 ablations. Most procedures used RFA, especially in the right upper lobe, and the majority of ablations were performed in the prone position (49.7%). Target lesions were at a median depth of 39.3 mm from the pleura surface, and remarkably, 91.9% required only a single puncture. Complications occurred in 31.0% of ablations, with pneumothorax being the most prevalent (18.3%), followed by pain (12.5%), sweating (6.5%), fever (5.0%), cough (4.8%), hemothorax (1.6%), hemoptysis (1.2%), pleural effusion (2.0%), skin burn (0.6%), and air emboli (0.2%). The median procedure time was 21 min. Notably, smoking/chronic obstructive pulmonary disease emerged as a significant risk factor for complications.

CONCLUSION

The LAGA-assisted LPTA enhanced safety by improving accuracy and reducing risks. Overall, this investigation contributes to the ongoing efforts to refine and improve the clinical application of these thermal ablation techniques in the treatment of lung tumors.

Combination of Minimally Invasive Methods for the Treatment of Varicose Veins

OBJECTIVE

The aim of the study was to evaluate the efficacy and safety of the combination of minimally invasive methods for the treatment of incompetent great saphenous vein and perforating veins.

METHODS

Between December 2019 and October 2020, F-care radiofrequency ablation combined with ultrasound-guided foam sclerotherapy and residual perforator ligation and concomitant microphlebectomy were adopted for all eligible patients. The clinical symptoms scores, complications, and quality of life were recorded.

RESULTS

49 patients (64 limbs) with a mean age of 63.29 ± 10.14 years, and 60.9%4 were male. The 1-year truncal closure rate was 63/64 (98.4%).1 A significant improvement in the Venous Disability Score, the Venous Segmental Disease Score, the Venous Clinical Severity Score and Chronic Venous Disease Quality of Life Questionnaire Score, at 12 months after the combination of minimally invasive treatment, were observed in the study. One patient developed intermuscular vein thrombosis that was successfully managed with rivaroxaban.

CONCLUSIONS

The combination of minimally invasive methods is a safe and effective method for the treatment of lower extremity varicose veins. Further large-scale, prospective, multi-center studies are needed to further verify the findings of this study.

The Impact of Radiofrequency Ablation on Survival Outcomes and Stent Patency in Patients with Unresectable Cholangiocarcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Endoluminal biliary radiofrequency ablation (RFA) has been proposed as a palliative treatment for patients with malignant biliary obstruction (MBO) in order to improve stent patency and survival. However, the existing data on patients with inoperable extrahepatic cholangiocarcinoma (eCCA) are conflicting. We performed a meta-analysis of randomized trials comparing RFA plus stenting versus stenting alone in patients with inoperable eCCA. We searched for trials published in the PubMed/MEDLINE, Scopus, and Cochrane databases up to November 2023. Data extraction was conducted from published studies, and a quality assessment was carried out in accordance with the guidelines recommended by the Cochrane Collaboration. Hazard ratios (HRs) with 95% CI were estimated from the trials. The primary endpoints of interest were overall survival and stent patency. Out of 275 results, 5 randomized trials and 370 patients were included. While overall survival was not different between the groups (HR 0.62; 95% CI 0.36-1.07; p = 0.09; I2 = 80%;), the subgroup analysis of studies employing plastic stents showed a trend toward better survival in the RFA-treated group (HR 0.42; 95% CI 0.22-0.80; p = 0.009; I2 = 72%). Stent patency was improved in patients receiving RFA (HR 0.64; 95% CI 0.45-0.90; p = 0.01; I2 = 23%). Adverse events were not different between the groups (OR 1.21; 95% CI 0.69-2.12; p = 0.50; I2 = 0%). Despite the promising results, high heterogeneity and potential biases in the included studies suggest the need for further high-quality randomized trials to explore the potential cumulative effects of RFA on CCA treatment outcomes.

A novel nomogram for prediction of intrahepatic recurrence-free survival in patients with HCC followed by radiofrequency ablation

OBJECTIVE

Although radiofrequency ablation (RFA) has been considered as the favourable treatment option for hepatocellular carcinoma (HCC), there still exist some challenges for new recurrence after RFA. The present study aims to determine the factors affecting recurrence and develop an effective model to predict intrahepatic recurrence-free survival (RFS).

METHODS

Patients with HCC followed by RFA between 2000 and 2021 were included in this study. Multivariable Cox regression analysis was used to determine the independent prognostic factors and establish the nomogram predicting intrahepatic RFS after RFA. The predictive performance of the nomogram was assessed according to the C-index, calibration plots, and Kaplan-Meier curves stratified by the tertiles.

RESULTS

A total of 801 sessions in 660 patients (including 1155 lesions) were enrolled into this study. Intrahepatic new recurrence was observed in all patients during the follow-up, and the mean intrahepatic RFS was 21.9 months in the present cohort. According to multivariate COX regression analysis, five independent prognostic factors affecting intrahepatic RFS were determined, including age, Child-Pugh class, tumour distribution, number of tumours, and a-fetoprotein (AFP). Based on all independent prognostic factors, the nomogram model was developed and evaluated, which achieved favourable discrimination and calibration.

CONCLUSION

This study established five independent prognostic factors and constructed a nomogram model to predict intrahepatic RFS for HCC patients followed by RFA. It could better help clinicians select RFA candidates, as well as offering the important information about whether patients need receive comprehensive treatment to prevent new recurrence after RFA.

ADVANCES IN KNOWLEDGE

(1) In this study, 5 preoperative clinic-pathological variables were determined as the independent prognostic factors affecting RFS after RFA in the current largest sample size. (2) Based on these independent prognostic factors, a prognostic nomogram predicting RFS after RFA was established, which may be used to select patients who benefit from RFA and could help both surgeons and patients provide useful information for choosing the personalized treatment.

Pudendal nerve blockade for persistent genital arousal disorder (PGAD): A clinical review and case report

BACKGROUND

Persistent genital arousal disorder (PGAD) is a condition characterized by unwanted and potentially painful genital sensations or spontaneous orgasms without stimulation. We present a case of a 55-year-old woman with refractory genital arousal disorder that was treated with serial pudendal nerve blocks.

CASE

RW is a 55-year-old woman with chronic pelvic pain, pudendal neuralgia, MDD, SI, GAD, CRPS, and persistent genital arousal disorder for 11 years. Her PGAD was refractory to conservative management, physical therapy, and bilateral clitoral artery embolization. We performed bilateral pudendal nerve blocks with Kenalog and Bupivacaine, which provided almost complete relief for 2-3 months. We performed a bilateral pudendal nerve radiofrequency ablation; however, there was minimal benefit. RW continues to have significant relief with serial pudendal nerve blocks.

SUMMARY AND CONCLUSION

Persistent genital arousal disorder is often refractory to medication and physical therapy requiring significant intervention such as entrapment surgery or artery embolization. Our case demonstrates pudendal nerve blocks as a potential treatment modality with minimal side effects.

Efficacy and safety of endoscopic cardia peripheral tissue scar formation (ECSF) for the treatment of refractory gastroesophageal reflux disease: A systematic review with meta-analysis

BACKGROUND

Endoscopic treatment is increasingly used for refractory gastroesophageal reflux disease (rGERD). Unlike the mechanism of conventional surgical fundoplication, gastroesophageal junction ligation, anti-reflux mucosal intervention, and radiofrequency ablation have extremely similar anti-reflux mechanisms; hence, we collectively refer to them as endoscopic cardia peripheral tissue scar formation (ECSF). We conducted a systematic review and meta-analysis to assess the safety and efficacy of ECSF in treating rGERD.

METHODS

We performed a comprehensive search of several databases, including PubMed, Embase, Medline, China Knowledge Network, and Wanfang, to ensure a systematic approach for data collection between January 2011 and July 2023. Forest plots were used to summarize and combine the GERD-health-related quality of life (HRQL), gastroesophageal reflux questionnaire score, and DeMeester scores, acid exposure time, lower esophageal sphincter pressure, esophagitis, proton pump inhibitors use, and patient satisfaction.

RESULTS

This study comprised 37 studies, including 1732 patients. After ECSF, significant improvement in gastroesophageal reflux disease health-related quality of life score (mean difference [MD] = 18.27 95% CI: 14.81-21.74), gastroesophageal reflux questionnaire score (MD = 4.85 95% CI: 3.96-5.75), DeMeester score (MD = 42.34, 95% CI: 31.37-53.30), acid exposure time (MD = 7.98, 95% CI: 6.03-9.92), and lower esophageal sphincter pressure was observed (MD = -5.01, 95% CI: -8.39 to 1.62). The incidence of serious adverse effects after ECSF was 1.1% (95% CI: 0.9%-1.2%), and postoperatively, 67.4% (95% CI: 66.4%-68.2%) of patients could discontinue proton pump inhibitor-like drugs, and the treatment outcome was observed to be satisfactory in over 80% of the patients. Subgroup analyses of the various procedures showed that all 3 types improved several objective or subjective patient indicators.

CONCLUSIONS

Based on the current meta-analysis, we conclude that rGERD can be safely and effectively treated with ECSF as an endoscopic procedure.

Sensor-Based Measurement Method to Support the Assessment of Robot-Assisted Radiofrequency Ablation

Digital surgery technologies, such as interventional robotics and sensor systems, not only improve patient care but also aid in the development and optimization of traditional invasive treatments and methods. Atrial Fibrillation (AF) is the most common cardiac arrhythmia with critical clinical relevance today. Delayed intervention can lead to heart failure, stroke, or sudden cardiac death. Although many advances have been made in the field of radiofrequency (RF) catheter ablation (CA), it can be further developed by incorporating sensor technology to improve its efficacy and safety. Automation can be utilized to shorten the duration of RF ablation, provided that the interactions between the tissue and the RF tools are well understood and adequately modeled. Further research is needed to develop the optimal catheter design. This paper describes the systematic methodology developed to support robot-assisted RF CA characterization measurements. The article describes the custom instruments developed for the experiments, particularly the contact force limiter, the measurement procedure, and the evaluation of the results, as enablers for new results. The aim was to establish an objective, repeatable, robust measurement method and adjacent procedure.

Long-term oncological results of percutaneous radiofrequency ablation for intrahepatic cholangiocarcinoma

INTRODUCTION

The effectiveness of percutaneous radiofrequency ablation (RFA) in intrahepatic cholangiocarcinomas (iCCA) remains insufficiently studied.

METHODS

We conducted a retrospective study including patients with histologically proven iCCA within Milan criteria treated by percutaneous RFA from 2000 to 2022. The primary outcome was overall survival in treatment-naive patients and secondary outcomes included ablation completeness, adverse events, local and distant recurrence. A total of 494 patients with hepatocellular carcinoma (HCC) on cirrhosis treated by RFA were included as a comparison group. Oncological events were analysed using Kaplan-Meier, log-rank and univariate/multivariate Cox models.

RESULTS

The main population included 71 patients, mostly cirrhotic (80%) with solitary tumours (66%) of a median size of 24 mm. Local recurrence was 45% at 5 years, lower in multibipolar versus monopolar RFA (22% vs. 55%, p = .007). In treatment-naive patients (n = 45), median overall and recurrence-free survivals were 26 and 11 months, respectively. Tumour size (p = .01) and Child-Pugh B (p = .001) were associated with death. The rate of distant recurrence was 59% at 5 years significantly lower for single tumours of less than 2 (p = .002) or 3 cm (p = .02). In cirrhotic patients naïve of previous treatment (n = 40), overall survival was shorter than in HCC (26 vs 68 months, p < .0001), with more local recurrences (p < .0001). Among distant recurrences, 50% were extrahepatic metastases compared to 12% in HCC (p < .001).

CONCLUSION

Multibipolar RFA provides better results in terms of tumour recurrence than monopolar RFA and could be used to treat small iCCA (<3 cm). Adjuvant chemotherapy should be discussed due to the frequent extra-hepatic metastasis at recurrence.

Catheter ablation for non-paroxysmal atrial fibrillation. A review

Atrial fibrillation (AF), the most common cardiac arrhythmia is associated with increased morbidity and mortality. The higher mortality is due to the risk of heart failure and cardioembolic events. This in-depth review focuses on the strategies and efficacy of catheter ablation for non-paroxysmal atrial fibrillation. The main medical databases were searched for contemporary studies on catheter ablation for non-paroxysmal AF. Catheter ablation is currently proven to be the most effective treatment for AF and consists of pulmonary vein isolation as the cornerstone plus additional ablations. In terms of SR maintenance, it is less effective in non-paroxysmal AF than in paroxysmal patients. but the clinical benefit in non-paroxysmal patients is substantially higher. Since pulmonary vein isolation is ineffective, a variety of techniques have been developed, e.g. linear ablations, ablation of complex atrial fractionated electrograms, etc. Another paradox consists in the technique of catheter ablation. Despite promising results in early observation studies, further randomized studies have not confirmed the initial enthusiasm. Recently, a new approach, pulsed-field ablation, appears promising. This is an in-depth summary of current technologies and techniques for the ablation of non-paroxysmal AF. We discuss the benefits, risks and implications in the treatment of patients with non-paroxysmal AF.

Clinical Outcomes of Thermal Ablation Re-Treatment of Benign Thyroid Nodules: A Multicenter Study from the Italian Minimally Invasive Treatments of the Thyroid Group

Background: Thermal ablation (TA) is an established therapeutic option alternative to surgery in patients with solid benign thyroid nodules causing local symptoms. However, a variable part of thyroid nodules remain viable after these nonsurgical treatments, and as many as 15% of nodules treated with TA may require a second treatment over time. This study aimed to evaluate the outcomes of TA re-treatment on symptomatic benign thyroid nodules where the volume decreased by <50% after the first procedure ( = technique inefficacy). Methods: We performed a multicenter retrospective cohort study including patients who underwent re-treatment with TA for benign thyroid nodules, whose volume decreased by <50% after initial treatment. The primary aim was to evaluate volume and volume reduction ratio (VRR) over time and compare the 6- and 12-month VRR after first versus second treatment. The secondary aim was to identify protective or risk factors for technique inefficacy, regrowth, and further treatments, expressed as adjusted hazard ratios (HRs) and confidence interval [CI], after adjustment for sex, age, nodule volume, structure and function, nodule regrowth or symptom relapse, technique used and if the same technique was used for the first and second TA and time between them. Results: We included 135 patients. Re-treatment led to VRR of 50% and 52.2% after 6 and 12 months. VRR after re-treatment was greater than after first treatment in small and medium size nodules (<30 mL), while there were no differences for large nodules (>30 mL). After re-treatment technique inefficacy rate was 51.9%, regrowth rate was 12.6%, and further treatment rate was 15.6%. Radiofrequency ablation (RFA) was protective toward technique inefficacy (HR = 0.40 [CI 0.24-0.65]) and need of further treatments (HR = 0.30 [CI 0.12-0.76]). Large nodule volume (>30 mL) was associated with increased risk of re-treatment (HR = 4.52 [CI 1.38-14.82]). Conclusions: This is the first study evaluating the outcomes of re-treatment on symptomatic benign thyroid nodules with a VRR <50% after the initial TA treatment. Best results were seen in small and medium nodules (<30 mL) and after RFA. Prospective confirmatory studies are needed.

Slow conduction velocity predicts atrial fibrillation recurrence after radiofrequency ablation

OBJECTIVE

To evaluate the progression of electrophysiological phenomena in atrial fibrillation (AF) and elucidate the association between the left atrial conduction velocity (LACV) and AF recurrence after pulmonary vein isolation.

METHODS

A total of 188 AF patients (121 paroxysmal AF and 67 persistent AF) who underwent PVI for the first time were enrolled in this prospective study. The left atrium was mapped using a 20-pole electrode catheter combined with the CARTO3 system. The conduction distances and conduction times of the left atrium from the Bachmann bundle area to the mitral isthmus were calculated. Anterior, posterior, and septal LACV were calculated as conduction distance divided by conduction time.

RESULTS

The anterior, posterior, and septal LACVs in the AF recurrence group were slower than those in the nonrecurrence group (anterior: 0.807 [0.766, 0.848] and 1.048 [1.000, 1.093] m/s, p < .05; posterior: 1.037 [0.991, 1.084] vs. 1.315 [1.249, 1.380] m/s, p < .05; septal: 0.904 [0.862, 0.946] vs. 1.163 [1.107, 1.219] m/s, p < .05). The best cut-off value of anterior LACV for predicting AF recurrence was 0.887 m/s (sensitivity 73.9% and specificity 76.5%). Multivariate analysis showed slow anterior LACV <0.887 m/s was an independent predictor of AF recurrence with an adjusted odds ratio of 1.42 (1.04, 1.94).

CONCLUSIONS

Slowing conduction velocity is a predictor of AF recurrence after pulmonary vein isolation.

Bipolar radiofrequency ablation lesion areas and confluence: An ex vivo study and technical report

INTRODUCTION

Radiofrequency ablation (RFA) has been used for nearly 100 years, treating an array of medical conditions including chronic pain. Radiofrequency (RF) energy depolarizes and repolarizes tissues adjacent to a probe producing heat and causing direct thermal injury. When positioned adjacent to neural structures, it leads to neural tissue injury and cell death interrupting pain signaling with the ultimate goal of providing lasting pain relief. Today, RFA is commonly used to treat cervical, thoracic, and lumbar zygapophyseal joints, sacroiliac joint, and more recently large peripheral joint-mediated pain. There are several applications of RFA systems, including bipolar, conventional thermal, cooled, protruding, and pulsed. As yet, no study has determined the best technical practice for bipolar RFA.

OBJECTIVE

This ex vivo study examines RFA lesion midpoint (LMP) area and lesion confluence comparing three different commonly used gauge (g) probes (18-g, 20-g, and 22-g) with 10-mm active tips at various interprobe distances (IPD) to guide best technical practices for its clinical application.

METHODS

Bipolar RFA lesions were generated in preservative-free chicken breast specimens using three different gauge probes (18-g, 20-g, and 22-g) with 10-mm active tips at various IPD (6, 8, 10, 12, 14, 16, and 18 mm). RF was applied for 105 s (15-s ramp time) at 80°C for each lesion at both room and human physiological temperature. The specimen tissues were dissected through the lesion to obtain a length, width, and depth, which were used to calculate the LMP area (mm2 ). The LMP areas of each thermal ablation were investigated using visualization and descriptive analysis. The Kruskal-Wallis test was performed to compare LMP areas between the two temperature groups and the three different gauge probe subgroups at the various IPDs.

RESULTS

Of the 36 RF lesions (14: 18-g, 12: 20-g, and 10: 22-g) performed, 24 demonstrated lesion confluence. The average time to reach 80°C was 16-17 s; therefore, the average time of RF-energy delivery (at goal temperature) was 88-89 s despite varying needle size or IPD. Comparing the 25 and 37°C groups, 18-g probes produced mean LMP areas of 73.7 and 79.2 mm2 , respectively; 20-g probes produced mean LMP areas of 66 and 66.8 mm2 , respectively; 22-g probes produced mean LMP areas of 56.6 and 59.7 mm2 , respectively. There was no statistical evidence to state a difference regarding LMP area between temperature groups; however, the 18-g probes produced consistently larger LMP areas in the 37°C compared to 25°C specimen groups at each IPD. Lesion confluence was lost for 18-g, 20-g, and 22-g probes at IPD of 14, 12, and 10 mm, respectively, in both 25 and 37°C groups. LMP area was similar between 6 and 8 mm IPD in all of the three-gauge groups; however, there was a significant drop in LMP area from 8 mm IPD to 10 mm and greater. The 18-g, 20-g, and 22-g probes all demonstrated a sharp decline in LMP area when increasing the IPD from 8 to 10 mm.

CONCLUSION

This ex vivo technical study evaluated bipolar RFA LMP areas and lesion confluence, and determined the recommended IPD of 18-g, 20-g, and 22-g probes to be less than 12, 10, and 8 mm, respectively, for best clinical practice. Placing bipolar probes at an IPD greater than 14, 12, and 10 mm, respectively, risks the loss of lesion confluence and failure to produce a clinically significant treatment response due to lack of nerve capture. In clinical practice, the use of injectate may produce larger lesions than demonstrated in this study. Additionally, in vivo factors may impact ablation zone size and ablation patterns. As there are a paucity of studies comparing various RFA applications and conventional RFA needles are least expensive, it is possible that bipolar conventional RFA is more cost-effective than other techniques.

Efficacy and safety between radiofrequency ablation and types of cryoablation catheters for atrioventricular nodal reentrant tachycardia: A Network Meta-analysis and Systematic Review

INTRODUCTION

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common supraventricular tachycardia referred for ablation. Periprocedural conduction system damage was a primary concern during AVNRT ablation. This study aimed to assess the incidence of permanent atrioventricular (AV) block and the success rate associated with different types of catheters in slow pathway ablation.

METHOD

A literature search was performed to identify studies that compared various techniques, including types of radiofrequency ablation (irrigated and nonirrigated) and different sizes of catheter tip cryoablation (4, 6, and 8-mm), in terms of their outcomes related to permanent atrioventricular block and success rate. To assess and rank the treatments for the different outcomes, a random-effects model of network meta-analysis, along with p-scores, was employed.

RESULTS

A total of 27 studies with 5110 patients were included in the analysis. Overall success rates ranged from 89.78% to 100%. Point estimation showed 4-mm cryoablation exhibited an odds ratio of 0.649 (95%CI: 0.202-2.087) when compared to nonirrigated RFA. Similarly, 6-mm cryoablation had an odds ratio of 0.944 (95%CI: 0.307-2.905), 8-mm cryoablation had an odds ratio of 0.848 (95%CI: 0.089-8.107), and irrigated RFA had an odds ratio of 0.424 (95%CI: 0.058-3.121) compared to nonirrigated RFA.

CONCLUSION

Our study found no significant difference in the incidence of permanent AV block between the types of catheters. The success rates were consistently high across all groups. These findings emphasize the potential of both RF ablation (irrigated and nonirrigated catheter) and cryoablation as viable options for the treatment of AVNRT, with similar safety and efficacy profile.