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).

Impact of wall thickness on the tissue cooling effect of cryoballoon ablation.

AIMS: Understanding of the tissue cooling properties of cryoballoon ablation during pulmonary vein (PV) isolation is lacking. The purpose of this study was to delineate the depth of the tissue cooling effect during cryoballoon freezing at the pulmonary venous ostium. METHODS AND RESULTS: A left atrial-PV model was constructed using a three-dimensional printer with data from a patient to which porcine thigh muscle of various thicknesses could be affixed. The model was placed in a 37°C water tank with a PV water flow at a rate that mimicked biological blood flow. Cryofreezing at the PV ostium was performed five times each for sliced porcine thigh muscle of 2, 4, and 6 mm thickness, and sliced muscle cooling on the side opposite the balloon was monitored. The cooling effect was assessed using the average temperature of 12 evenly distributed thermocouples covering the roof region of the left superior PV. Tissue cooling effects were in the order of the 2, 4, and 6 mm thicknesses, with an average temperature of -41.4 ± 4.2°C for 2 mm, -33.0 ± 4.0°C for 4 mm, and 8.0 ± 8.7°C for 6 mm at 180 s (P for trend <0.0001). In addition, tissue temperature drops were steeper in thin muscle (maximum temperature drop per 5 s: 5.2 ± 0.9°C, 3.9 ± 0.7°C, and 1.3 ± 0.7°C, P for trend <0.0001). CONCLUSION: The cooling effect of cryoballoon freezing is weaker in the deeper layers. Cryoballoon ablation should be performed with consideration to myocardial thickness.

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.

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.

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.

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.

Safety and efficacy of percutaneous cryoablation for primary and metastatic pleural based tumors.

PURPOSE: Assess safety and local tumor progression-free survival (LTPFS) of percutaneous cryoablation for pleural-based thoracic malignancies. MATERIALS AND METHODS: Retrospective study of 46 patients (17 treated for palliation; 9 for oligoprogression; 20 for curative intent), with 62 pleural-based thoracic lesions, treated in 59 cryoablation sessions. Patients were treated from 9/2005-11/2021 with CryoCare CS (Varian, Irvine, CA) or IceFORCE (Boston Scientific, Marlborough, MA) systems. For tumors treated with curative intent and/or oligoprogression, LTPFS of the treated tumor(s) and overall survival (OS) were estimated using Kaplan-Meier method. Post-operative complications were reported for all sessions, including those with palliative intent; univariate analyses were used to calculate factors associated with increased complication risk. RESULTS: Median number of tumors treated in a single treatment session was 1 (range 1-4). Largest dimension of the treated tumor was 2.1 cm [IQR:0.9-5 cm]. Of the 59 treatments, 98.3 % were technically successful. Median LTPFS was 14.4 (95 % CI: 9.4-25.6) months. Tumor size was a significant predictor of LTPFS (HR: 1.21, 95 % CI: 1.03-1.44, p = 0.023). Median OS was 52.4 (28.1-NR) months. Complications occurred in 28/59 sessions (47.5 %); 2/59 (3.4 %) were ≥ grade D by Society of Interventional Radiology adverse event criteria (death; hypoxia requiring supplemental oxygen upon discharge). Pain and pneumothorax were the most common complications. The length of lung parenchyma traversed was a significant predictor of pneumothorax: HR 0.48 (95 %CI: 0.14-0.83), p = 0.0024. CONCLUSION: Percutaneous cryoablation for pleural lesions is associated with a long duration of local control and most complications were minor and self-limited.

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.

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.

Evaluation of Conditions for the Development of Cryogenic Spinal Cord Injury Using a Canine Model: An Experimental Study on the Safety of Cryoablation for Metastatic Spinal Tumors.

BACKGROUND AND PURPOSE: Although the application of cryoablation to metastatic spinal tumors has been attempted, spinal cryoablation has the unique complication of cryogenic spinal cord injury. This study aimed to elucidate the conditions for the development of cryogenic spinal cord injury. MATERIALS AND METHODS: Fifteen canines were used in this study. A metal probe was inserted into the 13th thoracic vertebral body. Cryoablation was performed for 10 minutes by freezing the probe in liquid nitrogen. The control canine underwent probe insertion only. Spinal cord monitoring, epidural temperature measurement, motor function assessment, and pathologic examination of the spinal cord were performed. RESULTS: During the 10 minutes of cryoablation, the epidural temperature decreased and reached the lowest epidural temperature (LET) at the end of cryoablation. The LETs (degrees celsius [°C]) of each canine were -37, -30, -27, -8, -3, -2, 0, 1, 4, 8, 16, 18, 20, and 25, respectively. As the epidural temperature decreased, waveform amplitudes also decreased. At the end of cryoablation (10 minutes after the start of cryoablation), abnormal waves were observed in 92.9% (13/14) of canines. With epidural rewarming, the amplitude of the waveforms tended to recover. After epidural rewarming (2 hours after the start of cryoablation), abnormal waves were observed in 28.6% (4/14) of canines. The LETs (°C) of the canines with abnormal waves after epidural rewarming were -37, -30, -27, and -8. None of the canines with normal waves after epidural rewarming had any motor impairment. In contrast, all canines with remaining abnormal waves after epidural rewarming had motor impairment. In the pathologic assessment, cryogenic changes were found in canines with LETs (°C) of -37 -30, -27, -8, 0, and 1. CONCLUSIONS: This study showed that 10-minute spinal cryoablation with LETs (°C) of -37, -30, -27, -8, 0, and 1 caused cryogenic spinal cord injury. There was no evidence of cryogenic spinal cord injury in canines with LET of ≥4°C. The epidural temperature threshold for cryogenic spinal cord injury is between 1 and 4°C, suggesting that the epidural temperature should be maintained above at least 4°C to prevent cryogenic spinal cord injury.

Early Pneumatocele Identification Post-Robotic Assisted Bronchoscopy Cryobiopsy: A Case Series Experience.

INTRODUCTION: The use of cryobiopsy in conjunction with robotic assisted bronchoscopy is on the rise due to the safety and increased diagnostic yield of cryobiopsy. The incorporation of 3D fluoroscopy in the procedure improves the workflow and helps confirm the accuracy of sampling of peripheral pulmonary nodules. METHODS: We describe an observational series of 12 patients comprising 14 nodules where cryobiopsy was performed during shape-sensing robot-assisted bronchoscopy cryobiopsy under general anesthesia. 3D fluoroscopy was used to confirm accurate placement of the cryoprobe. All these patients underwent a second spin with the 3D fluoroscopy either to sample a second lesion intraoperatively or to investigate suspected pneumothorax. RESULTS: The development of a pneumatocele was noted after cryobiopsy in each of the cases. The majority of these were in the upper lobe with the median size of a sampled nodule being 14 mm. The majority of patients were asymptomatic with 1 patient developing mild hemoptysis and 4 patients developing chest tightness or dyspnea. None of the patients required an intervention for the pneumatocele. CONCLUSION: The development of pneumatoceles appears to be a fairly frequent and benign occurrence following cryobiopsy, likely due to increased tissue destruction. The increased use of intraoperative 3D fluoroscopy is likely to highlight changes to the pulmonary parenchyma that were previously not known. The occurrence of pneumatoceles does not appear to adversely impact the safety or tolerability profile of cryobiopsy.

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.

Cryoablation Reduces Opioid Consumption and Length of Stay After Pulmonary Metastasectomy.

INTRODUCTION: Intraoperative cryoablation of intercostal thoracic nerves is gaining popularity as a technique that decreases postoperative pain in thoracic surgery. Our study evaluates the efficacy and safety of cryoablation in pain management of pediatric cancer patients undergoing thoracotomy. METHODS: We reviewed cancer patients undergoing thoracotomies for pulmonary metastasis resection at our children's hospital from 2017 to 2023. Patients who received cryoablation were compared to those who did not. Our primary outcomes were self-reported postoperative pain scores (from 0 to 10) and opioid consumption, measured as oral morphine equivalent per kilogram. RESULTS: Thirty eight procedures were performed in 17 patients, of which 11 (64.7%) were males. Cryoablation was used in 14 (32.4%) procedures, while it was not in 24 (67.6%). Median age (17 y in both groups, P = 0.84) and length of surgery (300 cryoablation versus 282 no cryoablation, P = 0.65) were similar between the groups. Patients treated with cryoablation had a shorter hospital stay compared to those who did not (3.0 versus 4.5 d, respectively, P = 0.04) and received a lower total dose of opioids (2.2 oral morphine equivalent per kilogram versus 14.4, P = 0.004). No significant difference was noted in daily pain scores between the two groups (3.8 cryoablation versus 3.9 no cryoablation, P = 0.93). There was no difference in rates of readmissions between the cryoablation and no-cryoablation groups (14.3% versus 8.3%, P = 0.55). CONCLUSIONS: Our study suggests that cryoablation of the thoracic nerves during a thoracotomy is associated with reduced opiate consumption and shorter hospital stay. Cryoablation appears to be a promising technique for pain management in this patient population.

Low bleeding rates following transbronchial lung cryobiopsy in unclassifiable interstitial lung disease.

BACKGROUND AND OBJECTIVE: Bronchoscopic transbronchial lung cryobiopsy (TBLC) is a guideline-endorsed alternative to surgical lung biopsy for tissue diagnosis in unclassifiable interstitial lung disease (ILD). The reported incidence of post-procedural bleeding has varied widely. We aimed to characterize the incidence, severity and risk factors for clinically significant bleeding following TBLC using an expert-consensus airway bleeding scale, in addition to other complications and diagnostic yield. METHODS: A retrospective cohort study of consecutive adult outpatients with unclassifiable ILD who underwent TBLC following multidisciplinary discussion at a single centre in the UK between July 2016 and December 2021. TBLC was performed under general anaesthesia with fluoroscopic guidance and a prophylactic endobronchial balloon. RESULTS: One hundred twenty-six patients underwent TBLC (68.3% male; mean age 62.7 years; FVC 86.2%; DLCO 54.5%). Significant bleeding requiring balloon blocker reinflation for >20 min, admission to ICU, packed red blood cell transfusion, bronchial artery embolization, resuscitation or procedural abandonment, occurred in 10 cases (7.9%). Significant bleeding was associated with traction bronchiectasis on HRCT (OR 7.1, CI 1.1-59.1, p = 0.042), a TBLC histological pattern of UIP (OR 4.0, CI 1.1-14, p = 0.046) and the presence of medium-large vessels on histology (OR 37.3, CI 6.5-212, p < 0.001). BMI ≥30 (p = 0.017) and traction bronchiectasis on HRCT (p = 0.025) were significant multivariate predictors of longer total bleeding time (p = 0.017). Pneumothorax occurred in nine cases (7.1%) and the 30-day mortality was 0%. Diagnostic yield was 80.6%. CONCLUSION: TBLC has an acceptable safety profile in experienced hands. Radiological traction bronchiectasis and obesity increase the risk of significant bleeding following TBLC.

Percutaneous Microwave Ablation versus Cryoablation for Small Renal Masses (≤4 cm): 12-Year Experience at a Single Center.

PURPOSE: To determine whether microwave ablation (MWA) has equivalent outcomes to those of cryoablation (CA) in terms of technical success, adverse events, local tumor recurrence, and survival in adult patients with solid enhancing renal masses ≤4 cm. MATERIALS AND METHODS: A retrospective review was performed of 279 small renal masses (≤4 cm) in 257 patients (median age, 71 years; range, 40-92 years) treated with either CA (n = 191) or MWA (n = 88) between January 2008 and December 2020 at a single high-volume institution. Evaluations of adverse events, treatment effectiveness, and therapeutic outcomes were conducted for both MWA and CA. Disease-free, metastatic-free, and cancer-specific survival rates were tabulated. The estimated glomerular filtration rate was employed to examine treatment-related alterations in renal function. RESULTS: No difference in patient age (P = .99) or sex (P = .06) was observed between the MWA and CA groups. Cryoablated lesions were larger (P < .01) and of greater complexity (P = .03). The technical success rate for MWA was 100%, whereas 1 of 191 cryoablated lesions required retreatment for residual tumor. There was no impact on renal function after CA (P = .76) or MWA (P = .49). Secondary analysis using propensity score matching demonstrated no significant differences in local recurrence rates (P = .39), adverse event rates (P = .20), cancer-free survival (P = .76), or overall survival (P = .19) when comparing matched cohorts of patients who underwent MWA and CA. CONCLUSIONS: High technical success and local disease control were achieved for both MWA and CA. Cancer-specific survival was equivalent. Higher adverse event rates after CA may reflect the tendency to treat larger, more complex lesions with CA.

Association between baseline glycated hemoglobin level and atrial fibrillation recurrence following cryoballoon ablation among patients with and without diabetes.

OBJECTIVES: The study aims to assess the effect of baseline glycated hemoglobin (HbA1c) levels on atrial fibrillation (AF) recurrence following cryoballoon ablation in patients with and without diabetes. METHODS: Consecutive AF patients receiving first cryoballoon ablation between April 2018 and April 2021 were included. AF recurrence and other clinical outcomes were recorded for a minimum of 12 months post-ablation, with regular assessments at 3, 6, and 12 months, followed by annual check-ups. The primary outcome was AF recurrence after ablation at longest follow-up. Multivariate Cox proportional hazards regression models were utilized to calculate the hazard ratio (HR) and 95% CI per standard deviation (SD) increase of baseline HbA1c level. RESULTS: 335 patients were included in the analysis. The mean age was 61.7 years, 61.8% were male. 12.8% had type 2 diabetes, and 81.7% of patients had paroxysmal AF. The median level of HbA1c was 5.3%, and the mean CHA2DS2-VASc score was 1.8. All cryoballoon ablation procedures, utilizing a 28-mm balloon, achieved successful pulmonary vein isolation. Over a median follow-up of 18 months, 105 patients (31.3%) experienced AF recurrence. In multivariate Cox proportional hazards analysis, a higher HbA1c level, persistent AF (HR 1.91, 95% CI 1.08 to 3.39, P = 0.026), alcohol consumption (HR 2.67, 95% CI 1.33 to 5.37, P = 0.006), and Nadir RSPV (HR 1.04, 95% CI 1.00 to 1.08, P = 0.005) were significant predictors of AF recurrence. Per-SD increase of HbA1c was associated with a 1.75-fold increase risk of AF recurrence (HR 1.75, 95% CI 1.39 to 2.21, P < 0.001). Subgroup analysis revealed that a higher HbA1c level was associated with a higher risk of AF recurrence in patients with and without diabetes, and in patients with paroxysmal and persistent AF. CONCLUSION: Baseline HbA1c level was an independent predictor of AF recurrence following cryoablation, both in patients with and without diabetes.

Safety and Technical Feasibility of Percutaneous Renal Cryoablation of Central Tumors without Pyeloperfusion.

PURPOSE: To assess the safety and technical success of percutaneous cryoablation (PCA) without pyeloperfusion in 94 patients with central renal tumors. MATERIALS AND METHODS: A retrospective review of all central renal tumors treated by PCA without pyeloperfusion was performed. Central tumors were defined as those involving the renal sinus fat on preprocedural cross-sectional imaging. Patient demographics and baseline tumor characteristics were recorded. The details of the PCA procedure, primary and secondary technical success, rates of local recurrence, adverse events (AEs), cancer-specific survival (CSS), and overall survival (OS) were compiled. RESULTS: Ninety-four patients (48 females [51%]; mean age, 68.2 years [range, 38-87 years]) with 94 central renal tumors were included. The mean maximal tumor diameter and mean RENAL nephrometry score were 37 mm (range, 15-67 mm) and 8 (range, 4-11), respectively. Primary technical success was achieved in 94% (n = 88) of procedures. Of the patients who did not achieve primary technical success, 3 underwent successful repeat PCA (secondary technical success, 97%; n = 91/94). The other 3 patients were surveilled for residual disease. Twenty-four patients (26%) required hydrodissection during PCA. Six patients (6%) experienced major AEs after PCA including hemorrhage requiring embolization (n = 3), hemorrhage requiring transfusions with admission (n = 2), and perinephric abscess necessitating drain placement (n = 1). Twenty-two patients (23%) experienced minor AEs. Nine patients (10%) experienced local recurrence during the follow-up period. OS was 94% (n = 88/94), whereas CSS was 98% (n = 92/94) during the study follow-up period (mean, 16 months [range, 1-102 months]). CONCLUSIONS: PCA of central renal tumors appears to be safe with high rates of technical success, even without the use of pyeloperfusion.

Synergizing Thermal Ablation Modalities with Immunotherapy: Enough to Induce Systemic Antitumoral Immunity?

Thermal ablation modalities (cryoablation, radiofrequency ablation, and microwave ablation) have long been noted to occasionally induce a systemic antitumoral response. With the widespread use of checkpoint inhibitors, there is a significant interest in whether thermal ablation can promote immune system tumor recognition and increase checkpoint inhibitor response rates. In this review, we examine the current state of preclinical and clinical evidence examining the combination of checkpoint inhibitor therapies and thermal ablation modalities as well as discuss remaining the unanswered questions and directions for future research.