Pulsed field ablation with the pentaspline catheter compared with cryoablation for the treatment of paroxysmal atrial fibrillation in the UK NHS: a cost-comparison analysis.

OBJECTIVES: Pulsed field ablation (PFA) is a promising new ablation modality for the treatment of atrial fibrillation (AF) that has recently become available in the UK National Health Service (NHS). We provide the first known economic evaluation of the technology. METHODS: A cost-comparison model was developed to compare the expected 12-month costs of treating AF using the pentaspline PFA catheter compared with cryoablation for a single hypothetical patient. Model parameters were based on a recent cost-effectiveness analysis by the National Institute for Health and Care Excellence where possible or published literature otherwise. Deterministic sensitivity, scenario and threshold analyses were conducted. RESULTS: Costs for a single patient treated with PFA were -3% (-£343) less over 12 months than those who received treatment with cryoablation. PFA was associated with 16% higher catheter costs but repeat ablation costs were over 50% less, driven by a reduction in repeat ablations required. Costs of managing complications were -£211 less in total for PFA compared with cryoablation. CONCLUSIONS: Routine adoption of PFA with the pentaspline PFA catheter looks to be as affordable for the NHS as current treatment alternative cryoablation.

Cryoneurolysis versus radiofrequency ablation outcome on pain experience in chronic low back pain (COPE): a single-blinded randomised controlled trial.

OBJECTIVE: A comparison of cryoneurolysis or radio frequency (RF) with placebo in patients with facetogenic chronic low back pain (LBP) for patient global impression of change (PGIC), pain intensity, function and quality of life, with 1-year follow-up. DESIGN: Single-centre, single-blinded placebo-controlled randomised controlled trial. SETTING: Single-centre study. PARTICIPANTS: Inclusion from March 2020 to September 2022: consenting adults over 18 years of age, LBP>3 months, average Numeric Rating Scale LBP≥4 average last 14 days and a positive response to a diagnostic medial branch block (>50% pain reduction after 60 min). INTERVENTIONS: 120 patients were block randomised 1:1:1 to cryoneurolysis, RF or placebo of the medial branch nerves. Physical therapy was added after 4 weeks for all groups. MAIN OUTCOME MEASURES: Primary outcome was PGIC 4 weeks after the intervention. Secondary outcomes included pain intensity (Numeric Rating Scale, NRS), quality of life (Short Form 36, EQ-5D-5L), disability (Oswestry Disability Index), depression (Major Depression Inventory) and catastrophising (Pain Catastrophising Scale). Outcomes were measured at 4 weeks, 3, 6 and 12 months. RESULTS: There was no statistically significant difference in PGIC at 4 weeks between cryoneurolysis and placebo (risk ratio (RR) 2; 95% CI 0.75 to 5.33, p=0.17) and RF and placebo (RR 1.6; 95% CI 0.57 to 4.49, p=0.37), except PGIC for cryoneurolysis at 6-month follow-up (RR 5.1; 95% CI 1.20 to 22.03, p=0.03). No statistically significant differences were found in secondary follow-up endpoints. CONCLUSIONS: Denervation of the medial branch nerve by either cryoneurolysis or RF compared with placebo did not demonstrate significant improvement in PGIC, pain intensity, function and quality of life in patients with facetogenic chronic LBP at short-term or long-term follow-up. TRIAL REGISTRATION NUMBER: NCT04786145.

Assessment of a randomized controlled trial on the safety of pre-placing bronchial balloons in transbronchial lung cryobiopsy for diagnosing interstitial lung disease.

RATIONALE AND OBJECTIVES: Bleeding is a major complication of transbronchial lung cryobiopsy (TBLC), and pre-placing a bronchial balloon is one of the clinical practices used to prevent it, but with very weak evidence, which should be confirmed. This study aimed to conduct whether pre-placing a bronchial balloon in TBLC for diagnosing interstitial lung disease (ILD) is more safety. MATERIALS AND METHODS: In this prospective, single-center, randomized controlled trial, patients with suspected ILD were enrolled and randomly assigned to pre-placed balloon and none-pre-placed balloon groups. The primary outcome was incidence of moderate bleeding in each group. The secondary endpoints were the incidence of severe bleeding, pneumothorax, and other procedural complications. RESULTS: Exactly 250 patients were enrolled between August 2019 and March 2022, with 125 in each group. There were no significant differences in severe bleeding between the none-pre-placed balloon group and pre-placed balloon group (1.6% vs. 0.8%; adjusted p = 0.520), while more moderate bleeding occurred in the none-pre-placed balloon group (26.4% vs. 6.4%, adjusted p = 0.001), as well as more use of hemostatic drug (28.0% vs. 6.4%, adjusted p = 0.001). Three patients in the none-pre-placed balloon group used the bronchial balloon. More samples could be acquired in the pre-placed balloon group than in the none-pre-placed balloon group (3.8 ± 0.9 vs. 3.1 ± 0.9, p < 0.001). There were no significant differences in multidisciplinary discussion (MDD) between the two groups (89.6% vs. 91.2%, adjusted p = 0.182). CONCLUSION: A pre-placed bronchial balloon can reduce the incidence of moderate bleeding and increase the confidence of the bronchoscopists. However, it had no effect on increasing the diagnostic rate of MDD and reducing severe bleeding. REGISTRATION NUMBER: NCT04047667 ( www. CLINICALTRIALS: gov identifier).

Neoadjuvant in Situ and Systemic Immunotherapy with Lymph Node Cryoablation in Resectable Stage III Melanoma Metastasis: a Proof-of-Concept Study.

PURPOSE: Complete lymph node dissection is the recommended treatment for clinically detectable lymph nodes in stage III melanoma. This surgery is associated with substantial morbidity. We hypothesize that combining percutaneous imaging-guided cryoablation of locoregional lymph nodes metastases with neoadjuvant in situ and systemic immunotherapy could allow disease control and evaluate the feasibility of this combination in this proof-of-concept study. METHODS: We enrolled 15 patients with stage IIIB/IIIC melanoma. Patients were treated as follows: a single 240 mg flat dose infusion of nivolumab on day 1, cryoablation under local anesthesia using CT on day 2, and a single intralesional injection of 10-20 mg of ipilimumab into the lymphadenopathy treated by cryotherapy on day 3. Five-eight weeks after this procedure, complete lymph node dissection was performed according to routine care. The primary outcome measure of this study was feasibility, measured as the number of failures (i.e., inability to complete the entire procedure). RESULTS: The procedure was carried out successfully in 15 out of 15 patients with an observed number of failures of 0. The Bayesian analysis showed an estimated failure rate of 4.2% [0.2-20.6]. Eight patients (53%) had adverse events secondary to either immunotherapy or cryotherapy. Grade 3/4 events occurred in three patients, but all resolved quickly and patients could proceed to surgery as scheduled. Eight patients (53%) had a pathological complete or near complete response. CONCLUSION: Combining percutaneous cryotherapy with in situ ipilimumab and systemic nivolumab for stage III resectable melanoma is feasible with tolerable toxicity.

Association between body mass index and results of cryoballoon ablation in Korean patients with atrial fibrillation: an analysis from the Korean Heart Rhythm Society Cryoablation registry.

AIMS: Pulmonary vein isolation using cryoablation is effective and safe in patients with atrial fibrillation (AF). Although both obesity and underweight are associated with a higher risk for incident AF, there is limited data on the efficacy and safety following cryoablation according to body mass index (BMI) especially in Asians. METHODS AND RESULTS: Using the Korean Heart Rhythm Society Cryoablation registry, a multicentre registry of 12 tertiary hospitals, we analysed AF recurrence and procedure-related complications after cryoablation by BMI (kg/m2) groups (BMI < 18.5, underweight, UW; 18.5-23, normal, NW; 23-25, overweight, OW; 25-30, obese Ⅰ, OⅠ; ≥30, obese Ⅱ, OⅡ). A total of 2648 patients were included (median age 62.0 years; 76.7% men; 55.6% non-paroxysmal AF). Patients were categorized by BMI groups: 0.9% UW, 18.7% NW, 24.8% OW, 46.1% OI, and 9.4% OII. Underweight patients were the oldest and had least percentage of non-paroxysmal AF (33.3%). During a median follow-up of 1.7 years, atrial arrhythmia recurred in 874 (33.0%) patients (incidence rate, 18.9 per 100 person-years). After multivariable adjustment, the risk of AF recurrence was higher in UW group compared with NW group (adjusted hazard ratio, 95% confidence interval; 2.55, 1.18-5.50, P = 0.02). Procedure-related complications occurred in 123 (4.7%) patients, and the risk was higher for UW patients (odds ratio, 95% confidence interval; 2.90, 0.94-8.99, P = 0.07), mainly due to transient phrenic nerve palsy. CONCLUSION: Underweight patients showed a higher risk of AF recurrence after cryoablation compared with NW patients. Also, careful attention is needed on the occurrence of phrenic nerve palsy in UW patients.

Incidence of phrenic nerve injury during pulmonary vein isolation using different cryoballoons: data from a large prospective ablation registry.

AIMS: Phrenic nerve injury (PNI) is the most common complication during cryoballoon ablation. Currently, two cryoballoon systems are available, yet the difference is unclear. We sought to compare the acute procedural efficacy and safety of the two cryoballoons. METHODS: This prospective observational study consisted of 2,555 consecutive atrial fibrillation (AF) patients undergoing pulmonary vein isolation (PVI) using either conventional (Arctic Front Advance) (AFA-CB) or novel cryoballoons (POLARx) (POLARx-CB) at 19 centers between January 2022 and October 2023. RESULTS: Among 2,555 patients (68.8 ± 10.9 years, 1,740 men, paroxysmal AF[PAF] 1,670 patients), PVIs were performed by the AFA-CB and POLARx-CB in 1,358 and 1,197 patients, respectively. Touch-up ablation was required in 299(11.7%) patients. The touch-up rate was significantly lower for POLARx-CB than AFA-CB (9.5% vs. 13.6%, p = 0.002), especially for right inferior PVs (RIPVs). The touch-up rate was significantly lower for PAF than non-PAF (8.8% vs. 17.2%, P < 0.001) and was similar between the two cryoballoons in non-PAF patients. Right PNI occurred in 64(2.5%) patients and 22(0.9%) were symptomatic. It occurred during the right superior PV (RSPV) ablation in 39(1.5%) patients. The incidence was significantly higher for POLARx-CB than AFA-CB (3.8% vs. 1.3%, P < 0.001) as was the incidence of symptomatic PNI (1.7% vs. 0.1%, P < 0.001). The difference was significant during RSPV (2.5% vs. 0.7%, P < 0.001) but not RIPV ablation. The PNI recovered more quickly for the AFA-CB than POLARx-CB. CONCLUSIONS: Our study demonstrated a significantly higher incidence of right PNI and lower touch-up rate for the POLARx-CB than AFA-CB in the real-world clinical practice.

[Cryobiopsies for the differentiation of interstitial pneumopathies]. / Kryobiopsien zur Differenzierung interstitieller Pneumopathien.

INTRODUCTION: Cryobiopsies for the differentiation of interstitial pneumopathies Abstract: Definitive diagnosis of interstitial pneumopathy is often difficult. In order to establish antifibrotic therapy, it is necessary to narrow down the aetiology and, in up to 40% of cases, obtain histological confirmation. The establishment of the endoscopic method of cryobiopsy achieves a diagnostic yield of 76-80% with significantly fewer complications compared to surgical lung biopsy.

Cryocure-VT: the safety and effectiveness of ultra-low-temperature cryoablation of monomorphic ventricular tachycardia in patients with ischaemic and non-ischaemic cardiomyopathies.

AIMS: The ultra-low-temperature cryoablation (ULTC) ablation system using -196°C N2 cryogen has been reported to create lesions with freeze duration-dependent depth titratable to over 10 mm with minimum attenuation by scar. Cryocure-VT (NCT04893317) was a first-in-human clinical trial evaluating the safety and efficacy of a novel, purpose-built ULTC catheter in endocardial ablation of scar-dependent ventricular tachycardias (VTs). METHODS AND RESULTS: This prospective, multi-centre study enrolled patients referred for de novo or second ablations of recurrent monomorphic VT of both ischaemic and non-ischaemic aetiologies. Primary safety and efficacy endpoints of the study were freedom from device- or procedure-related major adverse events (MAEs) up to 30 days post-ablation, acute non-inducibility of clinical VTs at the end of the procedure, and freedom from sustained VT or implantable defibrillator intervention at 6 months. Ultra-low-temperature cryoablation was performed in 64 patients (age 67 ± 11 years, 78% ischaemic, ejection fraction = 35 ± 10%) at 9 centres. The primary acute effectiveness endpoint was achieved in 94% (51/54) of patients in whom post-ablation induction was attempted. There were no protocol-defined MAEs; four procedure-related serious adverse events resolved without clinical sequelae. At 6-month follow-up, 38 patients (60.3%) remained VT-free, and freedom from defibrillator shock was 81.0%, with no significant difference between ischaemic and non-ischaemic cohorts. In 47 patients with defibrillator for at least 6 months prior to the ablation, the VT burden was reduced from median of 4, inter-quartile range (IQR, 1-9) to 0, IQR (0-2). CONCLUSION: In this first-in-human multi-centre experience, endocardial ULTC ablation of monomorphic VT appears safe and effective in patients with both ischaemic-cardiomyopathy and non-ischaemic-cardiomyopathy. CLINICAL TRIAL REGISTRATION: NCT04893317.

Breast cryoablation for the palliative treatment of indolent subtype of multicentric triple-negative breast cancer.

Breast cryoablation for palliative and curative treatment of breast cancer has been performed for decades. Although there is a recent resurgence of interest in breast cryoablation with curative intent for unifocal, hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer, this report highlights the essential role that cryoablation can play in the palliative treatment of multicentric oestrogen and progesterone receptor-negative and human epidermal growth factor receptor 2-negative (triple-negative) breast cancer, meeting the select pretreatment objectives such as breast or nipple pain relief and prevention of tumour erosion through the skin or nipple in patients who have failed or cannot tolerate the standard of care treatment.

Safety and efficacy of the second-generation cryoballoon for left atrial appendage electrical isolation in canines.

AIMS: Left atrial appendage electrical isolation (LAAEI) has demonstrated a significant enhancement in the success rate of atrial fibrillation (AF) ablation. Nevertheless, concerns persist about the safety of LAAEI, particularly regarding alterations in left atrial appendage (LAA) flow velocity and the potential risks of thrombus. This study aimed to assess the efficacy and safety of LAAEI, investigating changes in LAA flow velocity in canines. METHODS AND RESULTS: The study comprised a total of 10 canines. The LAAEI procedure used by a 23 mm cryoballoon of the second generation was conducted at least 180 s. Intracardiac ultrasonography (ICE) was employed to quantify the velocity flow of the LAA both prior to and following LAAEI. Following a 3-month period, subsequent evaluations were performed to assess the LAA velocity flow and the potential reconnection. Histopathological examination was conducted. Left atrial appendage electrical isolation was effectively accomplished in all canines, resulting in a 100% acute success rate (10/10). The flow velocity in the LAA showed a notable reduction during LAAEI as compared with the values before the ablation procedure (53.12 ± 5.89 vs. 42.01 ± 9.22 cm/s, P = 0.007). After the follow-up, reconnection was observed in four canines, leading to a success rate of LAAEI of 60% (6/10). The flow velocity in the LAA was consistently lower (53.12 ± 5.89 vs. 44.33 ± 10.49 cm/s, P = 0.006), and no blood clot development was observed. The histopathological study indicated that there was consistent and complete injury to the LAA, affecting all layers of its wall. The injured tissue was subsequently replaced by fibrous tissue. CONCLUSION: The feasibility of using cryoballoon ablation for LAAEI was confirmed in canines, leading to a significant reduction of LAA flow velocity after ablation. Some restoration of LAA flow velocity after ablation may be linked to the passive movement of the LAA and potential reconnecting. However, this conclusion is limited to animal study; more clinical data are needed to further illustrate the safety and accessibility of LAAEI in humans.

Ablation of Kidney Tumors in Patients with Substantial Kidney Impairment: Current Status.

PURPOSE OF REVIEW: To review the current status of kidney tumor ablation in patients with substantial kidney impairment. RECENT FINDINGS: Few reports of kidney tumor ablation in such patients have recently been published. The reported prevalence of patients with stage 4 or 5 chronic kidney disease (CKD) among patients undergoing ablation is 2.0%-10%. In patients with stage 4 or 5 CKD, local tumor control rates were 88%-100%. The effect of ablation on CKD stage is unclear, and the observed deteriorations in kidney function are consistent with both the effect of cryoablation and the natural course of advanced CKD. According to guidelines, active surveillance may be selected. The goals of treatment are complete tumor removal and maintenance of kidney function, both of which can be met by ablation. Given the limited treatment options, ablation may play a pivotal role in the management of patients with advanced CKD.

Cryoballoon ablation for atrial fibrillation in South Africa: One-year outcome from the Cryo Global Registry.

BACKGROUND: Pulmonary vein isolation (PVI) with cryoballoon catheter ablation (CBA) is a well-established and widely adopted method for the treatment of patients with atrial fibrillation (AF) to prevent recurrences of AF. CBA adoption in South Africa (SA) and outcome data in SA patients are limited. OBJECTIVES: To evaluate real-world usage, safety and effectiveness of CBA in SA. METHODS: In this sub-analysis of the Cryo Global Registry, 81 participants with paroxysmal AF (PAF) and persistent AF (PsAF) were enrolled between 2017 and 2021 across two private SA hospitals. Baseline characteristics, procedural characteristics, 12-month safety, effectiveness (atrial arrhythmia recurrence), healthcare utilisation (repeat ablation and all-cause hospitalisation), quality of life (QoL; measured by EQ-5D-3L) and predefined symptoms were reported on. RESULTS: Participants in the SA cohort were a mean (standard deviation) of 60 (12) years old, 19 (23.5%) were female, and 48 (59.3%) presented with PAF. The overall presence of baseline comorbidities in the SA cohort was relatively low compared with the entire Cryo Global Registry cohort. The acute PVI success rate was high (98.8%). Two serious procedure-related adverse events occurred in 2 (2.5%) participants in the SA cohort. Freedom from arrhythmia recurrence was 97.4% (95% confidence interval (CI) 83.2 - 99.6%) in PAF and 78.4% (95% CI 58.1 - 89.7%) in persistent AF (p=0.035). Kaplan-Meier estimates for freedom from repeat ablations and all-cause hospitalisations were 97.0% (95% CI 88.4 - 99.2%) and 98.5% (95% CI 90.0 - 99.8%), respectively. Participants reported significant improvement in EQ-5D-3L index score and symptoms from baseline (0.90 (0.11)) - 12 months (0.97 (0.07), p<0.001). CONCLUSION: CBA standard-of-care procedures in SA resulted in a high clinical freedom from arrhythmia recurrence, with a low risk of safety events within 12 months post ablation. In addition, participants experienced an improvement in QoL and high freedom from healthcare utilisation at 12 months. The obtained results will be important for guiding clinical decisions around CBA in SA.

Intercostal nerve cryoablation versus thoracic epidural analgesia for minimal invasive Nuss repair of pectus excavatum: a protocol for a randomised clinical trial (ICE trial).

INTRODUCTION: Epidural analgesia is currently considered the gold standard in postoperative pain management for the minimally invasive Nuss procedure for pectus excavatum. Alternative analgesic strategies (eg, patient-controlled analgesia and paravertebral nerve block) fail in accomplishing adequate prolonged pain management. Furthermore, the continuous use of opioids, often prescribed in addition to all pain management strategies, comes with side effects. Intercostal nerve cryoablation seems a promising novel technique. Hence, the primary objective of this study is to determine the impact of intercostal nerve cryoablation on postoperative length of hospital stay compared with standard pain management of young pectus excavatum patients treated with the minimally invasive Nuss procedure. METHODS AND ANALYSIS: This study protocol is designed for a single centre, prospective, unblinded, randomised clinical trial. Intercostal nerve cryoablation will be compared with thoracic epidural analgesia in 50 young pectus excavatum patients (ie, 12-24 years of age) treated with the minimally invasive Nuss procedure. Block randomisation, including stratification based on age (12-16 years and 17-24 years) and sex, with an allocation ratio of 1:1 will be performed.Postoperative length of hospital stay will be recorded as the primary outcome. Secondary outcomes include (1) pain intensity, (2) operative time, (3) opioid usage, (4) complications, including neuropathic pain, (5) creatine kinase activity, (6) intensive care unit admissions, (7) readmissions, (8) postoperative mobility, (9) health-related quality of life, (10) days to return to work/school, (11) number of postoperative outpatient visits and (12) hospital costs. ETHICS AND DISSEMINATION: This protocol has been approved by the local Medical Ethics Review Committee, METC Zuyderland and Zuyd University of Applied Sciences. Participation in this study will be voluntary and informed consent will be obtained. Regardless of the outcome, the results will be disseminated through a peer-reviewed international medical journal. TRIAL REGISTRATION NUMBER: NCT05731973.

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.

Efficacy and Safety of Cryoablation Compared with Cooled Radiofrequency Ablation of Genicular Nerves in Advanced Osteoarthritis of the Knee: A Study Protocol of Single-Centric, Assessor-Blinded, Randomized, Parallel-Group, Non-inferiority Study.

PURPOSE: In patients with symptomatic osteoarthritis knee (OAK), cryoneurolysis (CRYO) and cooled radiofrequency ablation (C-RFA) are reported to be effective and safe; however, they have not been compared directly. The objective of this study is to compare CRYO and C-RFA of the genicular nerve (GN) in terms of efficacy and safety profile in patients with Kellgren and Lawrence (KL) grade ≥ 3 OAK. METHODS: This single-centric, assessor-blinded, randomized, parallel-group, non-inferiority study will include 80 patients with KL grade ≥ 3 OAK. The patients with ≥ 50% pain relief on diagnostic block of three GNs will be randomized to one of the two groups, i.e., CRYO (n = 40) or C-RFA (n = 40). The three target GNs for the interventions will include: superior medial, superior lateral, and inferior medial. The primary outcome will be efficacy of CRYO or C-RFA at 2, 12, and 24 weeks post-procedure based on the 11-point Numerical Pain Rating Scale. The secondary outcomes will be functional improvement based on 12-item Oxford Knee Score and safety of both the procedures. The study is registered in the Clinical Trials Registry-India. CONCLUSION: CRYO and C-RFA provide pain relief and improve functional outcome by preventing transmission of pain signals, though by distinct mechanisms. While C-RFA is an established treatment modality, recent evidence supports CRYO in patients with OAK. This study intends to demonstrate non-inferiority of CRYO against C-RFA, thereby supporting the use of CRYO as an additional treatment modality in patients with KL grade ≥ 3 OAK.

One-year outcomes of pulmonary vein isolation with a novel cryoballoon: Primary results of the FROZEN AF trial.

INTRODUCTION: Cryoablation therapy for pulmonary vein isolation (PVI) to treat paroxysmal atrial fibrillation (PAF) is well established. A novel 28 mm cryoballoon system designed to operate under low pressure to safely reach a lower nadir temperature and maintain constant balloon size during cooling has not been prospectively studied in a large patient population for safety and efficacy. The FROZEN AF (NCT04133168) trial was an international multicenter, open-label, prospective, single-arm study on the safety and performance of a novel cryoballoon system for treatment of PAF. METHODS AND RESULTS: The study enrolled patients at 44 sites in 10 countries across North America, Europe, and Asia. Subjects were indicated for PVI treatment of PAF and had failed or were intolerant of one or more antiarrhythmic drugs. Procedural outcomes were defined based on the 2017 HRS consensus statement. Follow-up was performed at 7 days, 3, 6, and 12 months. Data are reported as mean ± SD or median (IQR). PVI was performed with a 28 mm cryoballoon in 325 drug refractory PAF patients. Complete PVI was achieved in 95.7% of patients. In cryoablation lesions longer than 60 s, 60.1% of PV isolations required only a single cryoballoon application. Procedure related complications included: phrenic nerve palsy [temporary 4 (1.2%), persistent 0 (0.0%)], cardiac tamponade/perforation 2 (0.6%), and air embolism 1 (0.3%). Freedom from documented atrial arrhythmia recurrence at 12 months was 79.9% (AF 82.7%, AFL 96.5%, AT 98.1%), antiarrhythmic drugs (AAD) were continued or re-initiated in 26.8% of patients after the 3-month blanking period. Additionally, an extension arm enrolled 50 pts for treatment with 28/31 mm variable size cryoballoon. A single temporary PNP occurred in this group, which resolved before discharge. Freedom from documented recurrence at 12 months in these pts was 82.0%. CONCLUSIONS: This novel cryoballoon may facilitate PVI to treat PAF, providing more options to address the variety of anatomies present in patients with PAF. This cryoballoon system proved to be safe and effective for treatment of patients with drug refractory or drug intolerant PAF.

Pentaspline Pulsed Field Ablation Catheter Versus Cryoballoon for Atrial Fibrillation Ablation: Results From a Prospective Comparative Study.

BACKGROUND: Cryoballoon ablation is currently the gold standard technique for single-shot pulmonary vein isolation (PVI). Pulsed field ablation (PFA) has recently emerged as an interesting nonthermal alternative energy for PVI. The purpose of our study was to evaluate the safety and long-term efficacy of PVI using the pentaspline PFA catheter in comparison to cryoballoon ablation. METHODS AND RESULTS: Between January 2021 and December 2022, we included all consecutive patients of our center in whom a first PVI-only procedure was performed using PFA or cryoballoon. The choice of the energy was based on patients' preference between general anesthesia (PFA) and local anesthesia (cryoballoon). The primary end point was freedom from documented atrial arrhythmia recurrence after a 3-month blanking period. A total of 301 patients (paroxysmal atrial fibrillation in 220 patients) underwent a first PVI procedure performed using PFA (n=151) or cryoballoon (n=150). Complete short-term PVI was obtained in 144 of 150 patients (96%) in the cryoballoon group and in all patients of the PFA group (P=0.01). Procedure duration was significantly longer in the cryoballoon group. Transient and persistent phrenic nerve injuries were observed in the cryoballoon group only (13/150 and 2/150, respectively). One-year freedom from atrial arrhythmia was significantly higher in the PFA group compared with the cryoballoon group (87.9% versus 77.7%; adjusted hazard ratio, 0.53 [95% CI, 0.30-0.96]; P=0.037). CONCLUSIONS: This prospective, comparative, real-life study suggested that PFA could overcome safety limitations of cryoballoon with optimal effectiveness. Randomized controlled studies are required to further investigate the potential superiority of PFA over cryoballoon.

Size selection of intrahepatic lesions for cryoablation contributes to abscopal effect and long-term survival in patients with liver metastatic melanoma receiving PD-1 blockade therapy.

OBJECTIVES: In this study, we aimed to examine parameters of cryoablation, tumor characteristics, and their correlations with distant tumor response and survival of liver metastatic melanoma patients receiving cryoablation and PD-1 blockade (cryo-PD-1) combination treatment. MATERIALS AND METHODS: A retrospective study was conducted among 45 melanoma patients who received combined PD-1 blockade therapy and cryoablation for liver metastasis from 2018 to 2022. Cox regression was utilized to determine the associations between factors and overall survival (OS). Changes in cytokines and immune cell compositions in peripheral blood samples following the combined treatment were investigated, along with their correlations with treatment response. RESULTS: The mean cycle of cryo-PD-1 combination treatment was 2.2 (range, 1-6), and the 3-month overall response rate (RECIST 1.1 criteria) was 26.7%. Of the 21 patients who failed previous PD-1 blockade therapy after diagnosis of liver metastasis, 4 (19.0%) achieved response within 3 months since combination treatment. The diameter of ablated lesion ≤ 30 mm, metastatic organs ≤ 2, and pre-treatment LDH level ≤ 300 U/L were independent prognostic factors for favorable OS. Further analysis showed patients with intrahepatic tumor size of 15-45 mm, and ablated lesion size of ≤ 30 mm had significantly higher 3-month response rate (42.9% vs 12.5%; P = 0.022) and survival time (30.5 vs 14.2 months; P = 0.045) than their counterparts. The average increase in NLR among patients with ablated tumor size of ≤ 3 cm and > 3 cm were 3.59 ± 5.01 and 7.21 ± 12.57, respectively. The average increase in serum IL-6 levels among patients with ablated tumor size of ≤ 3 cm and > 3 cm were 8.62 ± 7.95 pg/ml and 15.40 ± 11.43 pg/ml, respectively. CONCLUSION: Size selection of intrahepatic lesions for cryoablation is important in order to achieve abscopal effect and long-term survival among patients with liver metastatic melanoma receiving PD-1 blockade therapy.