Ablation Therapy Research Articles

Machine learning-based model for predicting tumor recurrence after interventional therapy in HBV-related hepatocellular carcinoma patients with low preoperative platelet-albumin-bilirubin score.

This study aimed to develop a prognostic nomogram for predicting the recurrence-free survival (RFS) of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients with low preoperative platelet-albumin-bilirubin (PALBI) scores after transarterial chemoembolization (TACE) combined with local ablation treatment. We gathered clinical data from 632 HBV-related HCC patients who received the combination treatment at Beijing You'an Hospital, affiliated with Capital Medical University, from January 2014 to January 2020. The patients were divided into two groups based on their PALBI scores: low PALBI group (n=247) and high PALBI group (n=385). The low PALBI group was then divided into two cohorts: training cohort (n=172) and validation cohort (n=75). We utilized eXtreme Gradient Boosting (XGBoost), random survival forest (RSF), and multivariate Cox analysis to pinpoint the risk factors for RFS. Then, we developed a nomogram based on the screened factors and assessed its risk stratification capabilities and predictive performance. The study finally identified age, aspartate aminotransferase (AST), and prothrombin time activity (PTA) as key predictors. The three variables were included to develop the nomogram for predicting the 1-, 3-, and 5-year RFS of HCC patients. We confirmed the nomogram's ability to effectively discern high and low risk patients, as evidenced by Kaplan-Meier curves. We further corroborated the excellent discrimination, consistency, and clinical utility of the nomogram through assessments using the C-index, area under the curve (AUC), calibration curve, and decision curve analysis (DCA). Our study successfully constructed a robust nomogram, effectively predicting 1-, 3-, and 5-year RFS for HBV-related HCC patients with low preoperative PALBI scores after TACE combined with local ablation therapy.

Stereotactic central/core ablative radiation therapy: results of a phase I study of a novel strategy to treat bulky tumor

PurposeBulky tumor remains as a challenge to surgery, chemotherapy and conventional radiation therapy. Hence, in efforts to overcome this challenge, we designed a novel therapeutic paradigm via strategy of Stereotactic Central/Core Ablative Radiation Therapy (SCART).), which is based on the principles of SBRT (stereotactic body radiation therapy and spatially fractionated radiation therapy (SFRT). We intend to safely deliver an ablative dose to the core of the tumor and with a low dose at tumor edge. The purpose of the phase 1 study was to determine dose-limiting toxicities (DLT)s and the Maximum Tolerated Dose (MTD) of SCART.Methods and materialsWe defined a SCART-plan volume inside the tumor, which is proportional to the dimension of tumor. VMAT/Cyberknife technique was adopted. In the current clinical trial; Patients with biopsy proven recurrent or metastatic bulky cancers were enrolled. The five dose levels were 15 Gy X1, 15Gy X3, 18GyX3, 21GyX3 and 24GyX3, while keeping the whole tumor GTV’s border dose at 5Gy each fraction. There was no restriction on concurrent systemic chemotherapy agents.Results21 patients were enrolled and underwent SCART. All 21 patients have eligible data for study follow-up. Radiotherapy was well tolerated with all treatment completed as scheduled. The dose was escalated for two patients to 24GyX3. No grade 3 or higher toxicity was observed in any of the enrolled patients. The average age of patients was 66 years (range: 14–85) and 13 (62%) patients were male. The median SCART dose was 18Gy (range: 15 - 24). Six out of the 18 patients with data for overall survival (OS) died, and the median time to death was 16.3 months (range: 1 - 25.6). The mean percent change for tumor shrinkage between first visit volumes and post-SCART volumes was 49.5% (SD: 40.89, p-value:0.009).ConclusionSCART was safely escalated to 24 GyX 3 fractions, which is the maximum Tolerated Dose (MTD) for SCART. This regimen will be used in future phase II trials.

Outcomes of subcutaneous implantable cardioverter defibrillators: UK tertiary centre experience

Abstract Introduction Subcutaneous implantable cardioverter–defibrillators (S-ICDs) were introduced to address limitations associated with the transvenous ICDs (TVICDs). The programming features of the S-ICDs is however restricted compared to TVICDs. Our investigation aims to assess the outcomes of S-ICDs that have been implanted at our institution. Purpose To assess the outcomes of S-ICDs implanted at a tertiary healthcare centre in the United Kingdom. Methods A retrospective analysis was conducted, encompassing data from all individuals who underwent S-ICD implantation at our institution between January 2011 to April 2023 (n=240). Complications were categorized as device-related complications or inappropriate shock (IAS). All occurrences of IAS; lead revisions; infection; pocket hematoma requiring drainage, blood transfusion, or prolongation of hospitalization; and other complications prompting medical or surgical intervention were documented. The underlying causes and outcomes of IAS were reviewed. If S-ICD was either deactivated or explanted, the reasons for such actions were documented. Results Among the 240 patients included in the study, the average age is 46 years, with 66% being male. The average body mass index (BMI) is 27.8 and the ejection fraction (EF) is 43.3%. Comprehensive baseline characteristics are outlined in Table 1. Defibrillation testing (DFT) is a standard practice in our institution to ensure the integrity of S-ICDs and was conducted in all patients unless contraindicated. The success rate of DFT among attempted patients was 73%. The cumulative incidence of device-related complications over the study period was 15%. Eleven patients (4.6%) experienced IAS with T-wave oversensing as the leading cause. Patients undergoing S-ICD implantation for secondary prevention were found to be more susceptible to experiencing IAS (8 Vs 3, p=0.005) but no other baseline characteristics exhibited an association with any complications. The administration of beta-blockers and device reprogramming prevented further IAS in five patients. The remaining patients necessitated interventions such as lead revision, ablation therapy, switching to TVICD, or upgrading to cardiac resynchronisation therapy (CRT). A total of 38 patients required device explant or deactivation. The primary cause for such actions was due to patient mortality. The other notable causes included S-ICD infection, premature battery depletion, and IAS (Table 2). Conclusion Based on our findings, S-ICD emerges as a useful option for the prevention of sudden cardiac death in many patients. The decision regarding the selection of the appropriate ICD for individual patients warrants comprehensive discussion, encompassing a thorough discussion of advantages and disadvantages with the patients. We anticipate that the data elucidated in this study will be valuable in informing future patient care considerations.Table 1Baseline CharacteristicsTable 2Reasons

THerapy Efficacy in Short or long-coupled idiopathic ventricular fibrillation: an International Survey (THESIS)

Abstract Background A recent review of 86 patients with short or long-coupled premature ventricular complex (SLC-PVC) initiating idiopathic ventricular fibrillation (IVF) found high success rate in arrhythmia control with quinidine (QND) (83%) or radiofrequency ablation (RFA) (70.8%). Purpose To compare the efficacy of QND vs. RFA therapy in a large patient cohort with SLC-IVF. Methods THESIS included 287 patients with SLC-IVF screened from 58 centers and 1 multicenter group in 22 countries across 4 continents. The study cohort included 146 (50.9%) males, aged 39+14 years at the time of IVF documentation. Therapy groups were defined according to the first therapy given. Therapy success was defined as no VF recurrence. Results Patients presented after aborted cardiac arrest, ICD shocks, syncope, aborted cardiac arrest + arrhythmic storm, arrhythmic storm, palpitations, seizures or were asymptomatic in 121 (42%), 51(18%), 42(14.6%), 27 (9.4%), 23 (8%), 8 (2.8%), 6 (2.1%) and 9 (3.1%), respectively. Fifty-three patients (18.5%) had a prior history of syncope. Eleven (3.8%) patients required ECMO support. Mean shortest and longest coupling interval which triggered VF in the same patient were 304.9+82ms and 341.2+94.1ms, respectively. VF initiation with "long" coupled PVC (coupling interval >350ms) was observed in 41 (18.1%) patients, and VF initiation with both short and long coupled PVC was documented in 30 (13.2%) others. RFA was performed in 112 patients and QND was given to 68 patients. Patients were followed during a mean follow-up of 84.8+64.5 months. Therapy success was achieved in the RFA or QND group in 69 (62.2%) and 49 (71%) patients, respectively (p=0.29). The RV Purkinje was the main targeted ablation site in 46 (47.4%) patients. Treatment success varied according to the site of origin (SOO) of the PVC which triggered VF. Therapy success was higher with QND when PVC SOO based on ECG, was the RV inflow tract (81.3% vs. 57.7%, p=0.048) or when the SOO was not available (67.9% vs 36.4%, p=0.064), and when the coupling interval/QT ratio was <1 (75.5% vs. 57.5%, p=0.03), Figures 1,2. A higher success rate with ablation compared with QND was seen with LV- SOO compared with RV-SOO (82.1% vs 60.3%, p=0.019). Similarly, successful ablation was achieved in 83.3% (n=24) vs. 55.9% (n=68) patients with LV and RV-SOO respectively; p=0.004. One patient expired of sudden cardiac death due to misdiagnosis, while wearing a subcutaneous -ICD, without any drug or ablation therapy. Conclusions SLC-IVF strikes males and females equally. SLC-PVCs triggering the arrhythmia mainly arise from the RV Purkinje system. QND and RFA have similar efficacy in arrhythmia control. Quinidine has a higher treatment success rate in patients with PVC-SOO in the RV inflow area and in those with coupling interval/QT<1.Figure 1Treatment success by SOOFigure 2Treatment success by CI/QT

Influence of audiovisual distraction on the feeling of stress, analgesic sedation and patient satisfaction during electrophysiological ablation procedures on the heart

Abstract Background Distraction using audiovisual stimuli has mostly been researched in a paediatric population with the results showing an inhibiting effect on stress and anxiety as well as the subjective perception of pain. Purpose We designed a study to test if audiovisual distraction may reduce the level of sedatives and analgesics by reducing anxiety and stress during electrophysiological intervention (EP). Methods We conducted a clinical intervention pilot study that was carried out in a randomized controlled manner. Consecutive 70 patients undergoing EP with subsequent ablation were randomized 1:1 to control (CTL) or intervention group (AVD). In addition to standardized sedation, all patients in AVD group received audiovisual glasses. Feeling of fear and stress was assessed through blood pressure changes. The patient satisfaction was assessed with Client Satisfaction Questionnaire, ZUF-8. Numeric scale (NRS) was used to quantify the perceived pain during the procedure. The difference between the subjective estimated duration of the procedure and the actual duration of the procedure was compared. Results The study included predominantly male patients (58.6%) with a mean age of 56 years. Technical aptitude was well balanced between both groups with the majority of patients in both groups owning a smartphone or a tablet (86.1% vs 85.7% for CTL and AVD respectively, p=0.92), and majority of patients in both groups using a computer, laptop or tablet on a weekly basis (58% vs 57.1% for CTL and AVD group respectively, p=0.97). The baseline feelings of anxiety were well balanced within both groups (Figure 1). Our analysis revealed no significant difference between the mean blood pressure values of the CTL and AVD groups (systolic: 135 vs. 141 mmHg; p = 0.32; diastolic: 74 vs. 72 mmHg; p = 0.45). Patient satisfaction score was comparable in both groups (26.5 vs. 26.8 points, p = 0.36). Average response for perceived pain using NRS scale as well as perceived procedure duration was similar between the groups (Figure 2). AVD group required a lower dose of Midazolam than CTL group (0.005 mg/kg/h vs 0.007 mg/kg/h, p = 0.07). Majority of patients (31.4%) in AVD group stated: "The audiovisual glasses made me feel distracted at times." 10% of the AVD patients stated: "The audiovisual glasses made me feel completely distracted and more relaxed." Conclusion The use of audiovisual glasses has no influence on the patients’ feelings of anxiety and stress during EP. The use of audiovisual glasses can temporarily induce distraction during EP, while they do not seem to be sufficient in reducing pain intensity during ablation therapy. Patients undergoing EP do not seem to be the target patient group for AVD use.

Photoplethysmography recordings preceding onset atrial fibrillation show a higher heart rate variability - a TeleCheck-AF subanalysis

Abstract Background An increased heart rate variability (HRV), mostly assessed by 12-lead electrocardiogram (ECG) or long-term Holter monitoring, can be associated with the onset of atrial fibrillation (AF). Data evaluating HRV measurements using digital devices, especially those using photoplethysmography (PPG), in patients at risk for AF are sparse. In this analysis, we aimed to assess if hand-held-based non-continuous PPG measurements can provide short-term HRV to predict AF. Methods Patients from the TeleCheck-AF project with at least one PPG measurement in AF and one measurement in sinus rhythm (SR) were analyzed. Briefly, patients were provided with a PPG-based heart rate/rhythm monitoring smartphone app. They were instructed to record a PPG measurements three times daily and in case of symptoms for seven consecutive days. Short-term HRV using root mean square of successive normal-to-normal interval differences (RMSSD) was calculated in recordings in SR and compared between those not preceding and preceding an episode of AF (figure 1). Results Overall, 136 patients [56.3% men, median age 66 (59; 72) years] were included in the analysis. Median total number of recordings per patient was 24 (19; 30) including 4 (2;7) AF episodes per 1 week recording period. RMSSD was significantly higher in PPG measurements preceding an AF episode than in PPG measurements not preceding an AF episode [42.5 (33.2;70.7)ms vs. 41.1 (32.4;54.7)ms; p<0.001]. Between-group comparison revealed no significant difference for gender, age, previous ablation or betablocker therapy (p=0.824; p=0.484; p=0.519 and p=0.624, respectively). Conclusion Short-term HRV based on RMSSD, assessed by digital hand-held devices is significantly higher in PPG recordings preceding an AF episode than in measurements not preceding a consecutive AF episode. Whether PPG-recording derived short-term HRV can help to predict onset-AF warrants further study in larger populations. Figure 1: Patient example and exemplary analysis scheme, depicting the total number of recordings (n=14). HRV of recordings in sinus rhythm (SR) not preceding an episode of atrial fibrillation (AF) (A; grey circles) were compared to recordings preceding a consecutive AF episode (B; blue circles).Figure 1

Effectiveness of the Cooled Radiofrequency Ablation of Genicular Nerves in Patients with Chronic Knee Pain Due to Osteoarthritis: A Double-Blind, Randomized, Controlled Study.

Background: Increasing evidence supporting the clinical effectiveness of cooled radiofrequency ablation (RFA) therapy for genicular nerves in patients with chronic knee osteoarthritis (OA) exists. However, no study has been conducted to eliminate the potential influence of a placebo effect associated with this procedure. Therefore, we evaluated the efficacy of cooled RFA compared with a sham procedure in patients with painful knees due to OA. Methods: In this double-blind, randomized, controlled study, participants were randomly assigned to receive cooled RFA of the knee (cooled RFA group, n = 20) or a sham procedure (sham group, n = 20). The primary outcome was the proportion of successful responders at the three-month follow-up. The secondary outcomes were successful responders at one and six months; pain intensity of the knee; functional status; medication; and satisfaction at one, three, and six months after the procedures. Results: For the primary outcome, the successful responder rate was significantly higher in the cooled RFA group (76.5%) than in the sham group (33.3%) (p = 0.018). For the secondary outcome, more successful responders were observed in the cooled RFA group than in the sham group at one and six months after the procedure (p = 0.041 and 0.007, respectively). The decreased knee pain intensity was maintained throughout the six-month follow-up period in the cooled RFA group. No differences were observed in functional status, medication change, or satisfaction in both groups. Conclusions: The cooled RFA of genicular nerves offers significant pain relief and surpasses the effects attributable to a placebo.

An economic evaluation of first-line cryoballoon ablation versus antiarrhythmic drug therapy for the treatment of paroxysmal atrial fibrillation from a Danish healthcare perspective

Abstract Background As demonstrated in three randomized clinical trials (RCTs), initial rhythm control with first-line pulmonary vein isolation (PVI) using cryoballoon ablation decreases atrial arrhythmia recurrence compared to antiarrhythmic drug (AAD) therapy in patients with symptomatic paroxysmal atrial fibrillation (PAF). Purpose To assess the cost-effectiveness of first-line cryoablation versus first-line AADs in a Danish healthcare setting. Methods Data from 703 participants with symptomatic PAF enrolled into Cryo-FIRST, STOP AF First and EARLY-AF RCTs were used to estimate risk equations (rate of ablation, AF recurrence and resolution, AF-related hospital attendance in addition to health-related quality-of-life (HRQoL) utilities). These were then incorporated into a cost-effectiveness model (CEM) . The Danish cost data was derived from published Danish literature, DRG tariffs and pharmaceutical list prices in Denmark. Where parameters could not be derived, inputs were sourced from published literature or expert opinion. The CEM consisted of a decision tree (one-year time horizon) and a Markov model (three-month cycle length) hybrid, with a lifetime (40 years) time horizon. The CEM is from the perspective of the Danish healthcare system. Health benefits were expressed in quality-adjusted life-years (QALYs), and all costs and benefits were discounted at 3%. As there is no official cost-effectiveness threshold in Denmark, the UK threshold of £20,000 (~€23,200) was assumed. Input uncertainty within the CEM was explored using probabilistic sensitivity analysis. The results presented include data from the initial 12-week blanking period for all studies. Results The three-monthly rate of AF symptom recurrence had a reduction, on average, of 46.7% (p<0.001) in those treated with cryoablation. In addition, the cryoablation arm had a 72.8% (p<0.001) reduction in the monthly rate of receiving an ablation following initial treatment. The average cryoablation patient was also associated with a 4.3% (p=0.025) increase in their HRQoL. Finally, there was no difference in the rate of AF symptom resolution in those who failed initial treatment. Base case results per patient are presented in Table 1. Cryoablation was shown to be dominant when compared to AADs (0.159 more QALYs and €2,519 less costly), with a 99.96% probability of being cost-effective at a willingness-to-pay threshold of ~€23,200 per QALY gained. Individuals in both arms of the model were also expected to receive ~1.2 ablations over a lifetime horizon. Nonetheless, there was a 45% relative reduction in time spent in symptomatic AF states for individuals who were initially treated with cryoablation. Scenario analysis results are presented in Table 2. Cryoablation remained cost-effective over AADs in all scenarios conducted. Conclusions Initial rhythm control with cryoballoon ablation is cost-effective (dominant) when compared to AADs in the Danish healthcare system.Table 1:Key results (per patient)Table 2.Deterministic scenario analysis

Sex-related differences in clinical outcomes of patients with atrial fibrillation and heart failure with preserved ejection fraction

Abstract Background Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) are both highly prevalent diseases that commonly coexist, sharing clinical features and pathomechanisms. While prevalence of AF is higher in men compared to women with HFpEF, outcomes appear to be worse in women. However, there are no studies systematically examining gender-specific differences. Purpose Aiming for deeper insights into the effects of gender on clinical outcomes of patients with AF and HFpEF. Methods AF patients with HFpEF were included. HFpEF was diagnosed according to the current ESC guideline. Outcomes of men and women were compared. The primary endpoint was the time to heart failure hospitalization. Secondary endpoints were maintenance of sinus rhythm, as well as clinical and functional parameters. Factors related to a primary endpoint event were assessed. Results A total of 161 patients were included in our study (69 male patients, 92 female patients). Assessment of patient characteristics at baseline showed that male patients suffered more often from coronary artery disease (male: 45/69 patients (65%); female: 45/92 patients (49%); p=0.039), and OSAS (male: 14/69 patients (20%); female: 5/92 patients (5%); p=0.004). After a follow-up of 3 years, occurrence of the primary endpoint event was less frequent in women than in men (Hazard Ratio (HR): 0.61; 95% Confidence Interval (CI): 0.38-0.97; p=0.36; Figure A). By logistic regression analysis, we identified female sex (HR 0.48; 95%CI: 0.23-0.97; p=0.041), AF ablation (HR: 0.26; 0.13-0.53; p<0.001), and decrease in Left Ventricular Mass Index (LVMI) (HR:0.66; 95%CI: 0.44-0.98; p=0.041) as preventive factors with regard to heart failure hospitalization. Subgroup analysis for AF ablation versus medical therapy showed that patients who underwent ablation had lower hospitalization events (AF (HR: 0.49; 95% CI: 0.25-0.98; p=0.45). Additionally, left ventricular reverse remodeling, as assessed by the decrease of LVMI had a "dose-dependent" protective effect on heart failure hospitalizations (p=0.024, Figure B). Evaluation of functional HFpEF parameters revealed that only in women LVMI (baseline: 111 [99; 133] g/m2; follow-up: 105 [93; 127] g/m2; p=0.006), E/E’ ratio (baseline: 13.0 [10.2; 15.3]; follow-up: 11.5 [8.6; 14.7]; p=0.046), and NT-pro BNP serum levels (baseline: 1367 [352; 3605]; follow up: 987 [438; 2579]; p=0.039) improved. Discussion Our study suggests that women with AF and HFpEF have better outcomes as compared to men regarding heart failure hospitalization. LVMI and AF ablation are ssociated with fewer heart failure hospitalizations. Assessment of LVMI and further markers of HFpEF (E/E’ ratio and NT-pro BNP) only improved in women, suggesting that the gender-difference in heart failure hospitalization might be mediated by left ventricular induced remodeling following AF ablation. Further studies are necessary to verify this hypothesis generating results.Kaplan-Meier Analysis

Evaluating the efficacy of pre-ablation algorithms in WPW syndrome localization: a retrospective study

Abstract Background and Objective Wolf-Parkinson-White (WPW) syndrome is a congenital condition that can be diagnosed at any age and may lead to dysrhythmias, most notably atrioventricular reentrant tachycardia (AVRT). Ablation of the accessory pathway responsible for the disorder has become a standard treatment approach. The success of ablation therapy is closely linked to accurately localizing the accessory pathway. Consequently, algorithms have been developed to predict the location of the accessory pathway using pre-ablation electrocardiography (ECG) parameters. This study aims to evaluate the predictive values of previously published algorithms. Method This study included 122 patients diagnosed with WPW syndrome who underwent successful ablation of a manifest accessory pathway at our university's cardiac electrophysiology laboratory between 2019 and 2023. We retrospectively examined these patients' baseline characteristics and their procedures' features. Additionally, a team analyzed their baseline electrocardiograms (ECGs) using the EASY-WPW, Pambrun, and St. George algorithms. The sensitivity, specificity, PPV, and NPV of these algorithms were then calculated based on the location of the accessory pathways identified during the patients’ ablation treatments. Results The median age of the patients in this study was 33 years (18 - 79). Among them, 65 patients (53.3%) were male (Table 1). Ablation treatment was conducted using a 3D mapping system for all included patients, considering only those who achieved acute procedural success for analysis. The most frequently observed accessory pathway localization was the posteroseptal region of the tricuspid annulus, found in 48 patients (39.3%). Regarding the accuracy of accessory pathway prediction, the EASY-WPW, Pambrun, and St. George algorithms demonstrated correct localization rates of 81%, 72%, and 62%, respectively. The efficacy of these predictions varied according to the specific localization of the accessory pathways (Table 2). Conclusion This study highlights the limitations of previously published algorithms in predicting the localization of accessory pathways in WPW syndrome. The notably lower success rates observed in our research, as compared to earlier studies, might be attributed to variations in how localization is defined across studies, differences in the interpretation of these algorithms by users, or evolving definitions of localization resulting from advancements in 3-dimensional mapping systems. Given these findings, there is a clear need for the development of new algorithms that incorporate current localization definitions and are validated in larger patient cohorts.

Atrial functional mitral regurgitation as a marker of atrial remodeling and ablation outcomes in atrial fibrillation patients

Abstract Background Atrial fibrillation (AF) triggers a cascade of atrial remodeling processes, significantly impacting atrial function and the efficacy of ablation therapies. This remodeling fosters the development of atrial cardiomyopathy and atrial dilation, which is linked to the emergence of mitral regurgitation, paving the way for the concept of atrial functional mitral regurgitation (aFMR). Our study delves into the intricate relationship between aFMR and the electrical architecture of the atrium, specifically focusing on left atrial bipolar voltage and the prevalence and extent of low-voltage areas (LVAs) in AF patients. By exploring these associations, this research aims to deepen our understanding of the interplay between the atrial substrate alterations and the development of aFMR. Methods A total of 282 patients were enrolled, who had presented for a redo PVI procedure after experiencing AF recurrence following a previous PVI. All patients received echocardiography prior to the electrophysiological procedure. All procedures were performed using 3D mapping and radiofrequency ablation. Reconnected pulmonary veins were detected in all patients and were re-isolated. The voltage of the electroanatomical points was documented on each of the atrial walls. LVAs were calculated in selected HD maps. Patients were followed-up for one year after the blanking period. Results Our cohort comprised 282 patients, predominantly male (69.4%), with a mean age of 64 years. 56% of the patients presented with persistent AF. LA area was larger in patients with aFMR ≥ 1+ as compared to aFMR < 1+ (17.0 [14.6-19.7] vs 20.6 [16.6-24.7] cm2, p<0.001). We observed significant differences in left atrial voltage and LVA extent between patients with varying degrees of aFMR (Table 1). Upon further investigation Patients with aFMR = 1+ showed significantly lower atrial voltage compared with aFMR < 1+ yet no significant increase in LVAs area. Patients with aFMR = 2 exhibited lower average voltage amplitudes in all atrial regions and larger LVA in the posterior wall, atrial roof, and septum compared to their aFMR < 1+ counterparts. Notably, the recurrence of AF was significantly higher in the AFMR ≥ 1+ (59% vs 46% p=0.027) group within one year of follow-up. aFMR was associated with AF recurrence even after adjusting for sex, age and AF types (HR:1.517, 95% CI: 1.057-2.184, p=0.025). Conclusion The presence of aFMR in AF patients may serve as a marker of progressive atrial remodeling and the onset of left atrial cardiomyopathy, characterized by reduced atrial voltage and increased LVAs. Additionally, aFMR is linked to the outcomes of PVI, suggesting that aFMR should be considered in the decision-making process for AF therapy. Further research is needed to explore the potential reversibility of these changes.Left atrial voltage and low voltage area

Localization of ganglionated plexi by high density mapping: an atropine-response analysis

Abstract Introduction Growing interest has emerged around cardiac autonomic nervous system driven by ablation approaches for the treatment of neurally-mediated syncope (NMS). Ganglionated-plexi (GPs) located in the epicardial fat pads are the main target of ablative therapies, but little is known about the finest method to track their location from the endocardium. Most current techniques rely on empirical research of signal fragmentation and/or vagal response at anatomical landmarks. A poor accuracy in targeting GPs may lead to the risk of incomplete or over-extensive ablation. Purpose We analyzed the atrial electrograms (EGMs) in healty subjects and their response to atropine to describe physiological fragmentation and the relationship with vagal output. Methods Study partecipants were selected from young patients without structural heart desease who underwent electrophysiological study (EPS) for standard indications. High-density mapping of right atrium was performed before and after administration of 2 mg atropine at the end of the planned procedure. Offline analyses were performed comparing the two maps of each patient focusing on the fragmentation of the atrial EGMs. Results The study cohort comprised 10 patients (mean age of 39±11 years, 6 males). The indication for EPS was: supraventricular tachycardia (SVT) ablation in 9 patients, syncope in 1 patient. High density three-dimensional electro-anatomic maps (EAM) were all obtained with a multipolar catheter during sinus rhythm (number of points: 8794±937 in basal maps and 9007±1296 after atropine, p=0,87). The response to atropine was documented by an increase in heart rate (mean increase 59 ± 19% of basal cycle length). All basal maps showed a similar pattern of fragmentation in the posterior-septal wall reflecting the anatomical distribution of right GPs. In particular, three main stations were identified in the supero-, mid- and infero-posterior regions. Fragmentation of EGMs was found to progress from the edge to the core of each area. After administration of atropine, a reduction in fractionated area was observed in all patients. Filtering the maps according to a cut-off of fragmentation ≥ 6 peaks allowed identification of the nucleus with the highest degree of variation after atropine injection (mean basal area = 0,89 ± 0,81 cm2 ; mean atropine area = 0,44 ± 0,56 cm2 p<0,001). Conclusion Fragmentation of atrial electrograms is a dynamic property related to vagal output. High density mapping with a high pass filter of 6 peaks allows to identify the smallest vagal sensitive area in the anatomical stations of the GPs.

Local Ablative Therapy Combined With Pembrolizumab in Patients With Synchronous Oligometastatic Non-Small Cell Lung Cancer: A Recursive Partitioning Analysis

Purpose: This study aimed to evaluate the efficacy of local ablative therapy (LAT) combined with pembrolizumab in patients with synchronous oligometastatic non-small cell lung cancer (NSCLC) and to identify patients who would most benefit from LAT.Methods and Materials: We retrospectively identified patients diagnosed with synchronous oligometastatic NSCLC (≤5 metastatic lesions and ≤3 organs involved) and treated with first-line pembrolizumab between January 2017 and December 2022. Patients who underwent LAT, including surgery or radiotherapy at all disease sites, were compared with those who did not undergo LAT. A recursive partitioning analysis (RPA) model was developed using prognostic factors for progression-free survival (PFS).Results: Among the 258 patients included, 78 received LAT with pembrolizumab and 180 received pembrolizumab alone. The median follow-up duration was 15.5 months (range, 3.0–71.2). In the entire cohort, LAT was independently associated with significantly improved PFS (hazard ratio [HR], 0.64; P = 0.015) and overall survival (OS) (HR, 0.61; P = 0.020). In the propensity score-matched cohort (N = 74 in each group), the median PFS was 19.9 months and 9.6 months, respectively (P = 0.003), and the median OS was 42.2 months and 20.5 months, respectively (P = 0.045), for the LAT and non-LAT groups. Based on the RPA model, incorporating the number of metastatic lesions, performance status, and PD-L1 expression level, patients were stratified into three risk groups with distinct PFS. LAT significantly improved PFS and OS in the low- and intermediate-risk groups; however, no difference was observed in the high-risk group. LAT was more effective as a consolidative treatment following pembrolizumab initiation than as an upfront therapy.Conclusion: LAT combined with pembrolizumab was associated with higher PFS and OS compared to pembrolizumab alone in selected patients with synchronous oligometastatic NSCLC. The RPA model could serve as a valuable clinical tool for identifying appropriate patients for LAT.

Alternative treatments of adenomyosis - an update in procedural management and clinical outcomes.

Adenomyosis is a common cause of abnormal uterine bleeding (AUB), dysmenorrhea, and pelvic pain. Definitive diagnosis and treatment have historically been by uterine histopathology at time of hysterectomy; however, advances in imaging have supported earlier diagnosis and subsequent conservative treatment. This review aims to update the evidence supporting the uterine-sparing, procedural management options with a focus on clinical outcomes. Uterine artery embolization (UAE), radiofrequency ablation (RFA), high-intensity focused ultrasound (HIFU), percutaneous microwave ablation (PMWA), and adenomyomectomy are minimally invasive interventions proven to be effective in reducing AUB and dysmenorrhea due to adenomyosis. Symptom improvement is associated with a decrease in uterine volume. Studies support the use of alternative treatment options given the overall low rates of symptom recurrence and reintervention. Combination therapy may be more effective than monotherapy. This review provides the current evidence for use of alternative treatment options for adenomyosis. Access to ablative therapies in the USA is limited and primarily off label, given lack of FDA approval. High-quality prospective and randomized controlled trials are needed in order to further delineate treatment comparisons, efficacy, safety, and ideal patient selection for these treatments. More data are needed to assess safety and utility in those desiring future fertility.

Structure-specific rigid dose accumulation dosimetric analysis of ablative stereotactic MRI-guided adaptive radiation therapy in ultracentral lung lesions.

Definitive local therapy with stereotactic ablative radiation therapy (SABR) for ultracentral lung lesions is associated with a high risk of toxicity, including treatment related death. Stereotactic MR-guided adaptive radiation therapy (SMART) can overcome many of the challenges associated with SABR treatment of ultracentral lesions. We retrospectively identified 14 consecutive patients who received SMART to ultracentral lung lesions from 10/2019 to 01/2021. Patients had a median distance from the proximal bronchial tree (PBT) of 0.38 cm. Tumors were most often lung primary (64.3%) and HILUS group A (85.7%). A structure-specific rigid registration approach was used for cumulative dose analysis. Kaplan-Meier log-rank analysis was used for clinical outcome data and the Wilcoxon Signed Rank test was used for dosimetric data. Here we show that SMART dosimetric improvements in favor of delivered plans over predicted non-adapted plans for PBT, with improvements in proximal bronchial tree DMax of 5.7 Gy (p = 0.002) and gross tumor 100% prescription coverage of 7.3% (p = 0.002). The mean estimated follow-up is 17.2 months and 2-year local control and local failure free survival rates are 92.9% and 85.7%, respectively. There are no grade ≥ 3 toxicities. SMART has dosimetric advantages and excellent clinical outcomes for ultracentral lung tumors. Daily plan adaptation reliably improves target coverage while simultaneously reducing doses to the proximal airways. These results further characterize the therapeutic window improvements for SMART. Structure-specific rigid dose accumulation dosimetric analysis provides insights that elucidate the dosimetric advantages of SMART more so than per fractional analysis alone.

Partial Hepatectomy and Ablation for Survival of Early-Stage Hepatocellular Carcinoma Patients: A Bayesian Emulation Analysis.

Partial hepatectomy and ablation therapy are two widely used surgical procedures for localized early-stage hepatocellular carcinoma (HCC) patients. This article aimed to evaluate their relative effectiveness in terms of overall survival. An emulation analysis approach was first developed based on the Bayesian technique. We estimated propensity scores via Bayesian logistic regression and adopted a weighted Bayesian Weibull accelerated failure time (AFT) model incorporating prior information contained in the published literature. With the Surveillance, Epidemiology, and End Results (SEER)-Medicare data, an emulated target trial with rigorously defined inclusion/exclusion criteria and treatment regimens for early-stage HCC patients over 66 years old was developed. For the main cohort with tumor size less than or equal to 5 cm, a total of 1146 patients were enrolled in the emulated trial, with 301 and 845 in the partial hepatectomy and ablation arms, respectively. The analysis suggested ablation to be significantly associated with inferior overall survival (hazard ratio [HR] = 1.35; 95% credible interval [CrI]: 1.14, 1.60). For the subgroup with tumor size less than or equal to 3 cm, there was no significant difference in overall survival between the two arms (HR = 1.15; 95% CrI: 0.88, 1.52). Overall, the comparative treatment effect of ablation and partial hepatectomy on survival remains inconclusive. This finding may provide further insight into HCC clinical treatment.

Stereotactic Body Radiotherapy in Recurrent and Oligometastatic Head and Neck Tumours.

The treatment of head and neck cancers (HNCs) encompasses a complex paradigm involving a combination of surgery, radiotherapy, and systemic treatment. Locoregional recurrence is a common cause of treatment failure, and few patients are suitable for salvage surgery. Reirradiation with conventional radiation techniques is challenging due to normal tissue tolerance limits and the risk of significant toxicities. Stereotactic body radiotherapy (SBRT) has emerged as a highly conformal modality that offers the potential for cure while limiting the dose to surrounding tissue. There is also growing research that shows that those with oligometastatic disease can benefit from curative intent local ablative therapies such as SBRT. This review will look at published evidence regarding the use of SBRT in locoregional recurrent and oligometastatic HNCs.

Technical principles of ablation therapy

Catheter ablation is astandard procedure in modern cardiology. It can significantly improve the quality of life and life expectancy of cardiac arrhythmia patients. Besides cardiac mapping, ablation itself is afundamental step tosuccessfully treat cardiac arrhythmias. There are various ablation technologies at hand: In traditional radiofrequency (RF) ablation, electrical current flow generates coagulation necrosis. When understanding the biophysical principles of RF ablation, the investigator is capable to adapt lesion geometry and size to the requirements of the procedure and vary them individually. In addition, lesion metric indices evaluate and integrate important parameters such as power, duration, impedance and contact force to standardize and control RF lesions. Cryoablation induces ice crystals within myocardial tissue, which lead to destruction and electrical scarring of the treated tissue. Histologically, cryolesions are well-delineated with preserved tissue architecture and intact endocardium. Pulsed field ablation (PFA) is anovel rising technology, particularly used for pulmonary vein isolation. In contrast to classic thermal technologies (RF and cryoablation), PFA uses pulsed electrical fields to electroporate cardiac tissue and thereby creates damage on acellular level only.

Thermometry mapping during CT-guided thermal ablations: proof of feasibility and internal validation using spectral CT

Objective. Conventional computed tomography (CT) imaging does not provide quantitative information on local thermal changes during percutaneous ablative therapy of cancerous and benign tumors, aside from few qualitative, visual cues. In this study, we have investigated changes in CT signal across a wide range of temperatures and two physical phases for two different tissue mimicking materials, each. Approach. A series of experiments were conducted using an anthropomorphic phantom filled with water-based gel and olive oil, respectively. Multiple, clinically used ablation devices were applied to locally cool or heat the phantom material and were arranged in a configuration that produced thermal changes in regions with inconsequential amounts of metal artifact. Eight fiber optic thermal sensors were positioned in the region absent of metal artifact and were used to record local temperatures throughout the experiments. A spectral CT scanner was used to periodically acquire and generate electron density weighted images. Average electron density weighted values in 1 mm3 volumes of interest near the temperature sensors were computed and these data were then used to calculate thermal volumetric expansion coefficients for each material and phase. Main results. The experimentally determined expansion coefficients well-matched existing published values and variations with temperature—maximally differing by 5% of the known value. As a proof of concept, a CT-generated temperature map was produced during a heating time point of the water-based gel phantom, demonstrating the capability to map changes in electron density weighted signal to temperature. Significance. This study has demonstrated that spectral CT can be used to estimate local temperature changes for different materials and phases across temperature ranges produced by thermal ablations.

Experimental study for in vitro prostate cancer treatment with microwave ablation and pulsed electromagnetic field

ABSTRACT This paper presents the findings of a comprehensive study exploring the synergistic effects arising from the combination of microwave ablation and pulsed electromagnetic field (PEMF) therapy on prostate cancer cells. The research encompassed five distinct experimental groups, with continuous electric field measurements conducted during the entire treatment process. Group 1 and Group 2, subjected to microwave power below 350 W, exhibited specific electric field values of 72,800 V/m and 56,600 V/m, respectively. In contrast, Group 3 and Group 4, exposed to 80 W microwave power, displayed electric field levels of approximately 1450 V/m, while remaining free from any observable electrical discharges. The migratory and invasive capacities of PC3 cells were assessed through a scratch test in all groups. Notably, cells in Group 3 and Group 4, subjected to the combined treatment of microwave ablation and PEMF, demonstrated significantly accelerated migration in comparison to those in Groups 1 and 2. Additionally, Group 5 cells, receiving PEMF treatment in isolation, exhibited decreased migratory ability. These results strongly suggest that the combined approach of microwave ablation and PEMF holds promise as a potential therapeutic intervention for prostate cancer, as it effectively reduced cell viability, induced apoptosis, and impeded migration ability in PC3 cells. Moreover, the isolated use of PEMF demonstrated potential in limiting migratory capacity, which could hold critical implications in the fight against cancer metastasis.