Safety Of Cryoablation Research Articles

Efficacy and Safety of Cryoablation in Barrett's Esophagus and Comparison with Radiofrequency Ablation: A Meta-Analysis.

The mainstay approach in endoscopic eradication therapy (EET) for dysplastic Barrett's esophagus (BE) includes the endoscopic resection of visible lesions, accompanied by ablation of the residual metaplastic epithelium. Cryoablation therapy is one such emerging ablation technique in this field. This systematic review with a meta-analysis aims to accumulate pooled data on cryoablation performance in the treatment of patients with BE and to compare this technique to the standard of care radiofrequency ablation (RFA). The MEDLINE, Cochrane, and Scopus databases were searched until June 2024 for studies evaluating BE management using cryoablation for cumulative results. The primary outcome was the complete eradication of dysplasia (CED) and intestinal metaplasia (CEIM) in BE compared to RFA, while secondary outcomes included the respective pooled rates using cryoablation, recurrence, and adverse events, with a separate analysis for strictures. The meta-analyses were based on a random-effects model, and the results were reported as odds ratios (ORs) with 95% confidence intervals (CIs). Subgroup analyses by type of cryoablation were also performed. Twenty-three studies (1604 patients) were finally included, four of which were comparative. CED and CEIM did not differ significantly between cryoablation and RFA [OR= 0.95 (95%CI: 0.50-1.81) and OR = 0.57 (95%CI: 0.20-1.63), respectively)]. The pooled rates of CED, CEIM, and recurrence after cryoablation were 84.2% (95%CI: 79.1-89.3), 64.1% (95%CI: 49.2-79.0), and 8.3% (95%CI: 4.7-11.9), accompanied by high rates of heterogeneity. Adverse events were noted in 14.5% (95%CI: 9.9-19.2) of cases, and 6.5% (95%CI: 4.1-9.0) developed strictures. In the subgroup analysis, the cryoballoon achieved a reduction in heterogeneity in CED, adverse events, and stricture formation, whereas spray catheters provided homogenous results in terms of recurrence. Cryoablation provides equal outcomes compared to RFA in the treatment of patients with BE, with the cryoballoon achieving relatively homogenous rates of CED and adverse events.

Cryoablation Utilizing the KODEX-EPD Mapping System Versus Conventional Cryoballoon Ablation in the Management of Patients With Atrial Fibrillation: A Literature Review and Meta-Analysis.

Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia globally. AF is associated with different consequences, such as peripheral vascular embolism, stroke, dementia, heart failure, and death. Catheter ablation (CA) has become a reliabletherapeutic option for symptomatic AF. Utilizing mapping systems in conducting cryoablation is supposed to improve pulmonary vein isolation (PVI) durability and overall treatment success rate. We performed a review of relevant articles. We formulated a search strategy as follows: (atrial fibrillation AND ("cryoballoon ablation" OR cryoablation) AND (KODEX-EPD AND KODEX OR mapping). Data were collected from Web of Science, PubMed, Cochrane Library, and SCOPUS databases. We assessed the efficacy, procedural characteristics, and safety of cryoablation using the KODEX-EPD mapping system versus conventional cryoablation. We demonstrated the superiority of cryoablation guided by the KODEX-EPD system as it was associated with a significantly lower recurrence rate after the procedure (RR = 0.61, P = 0.03). Furthermore, it allowed a significant reduction in the volume of contrast medium used during the procedure (MD = -20.46, P = 0.04) when compared to the conventional cryoablation. We found no significant difference between both procedures in terms of successful cryoballoon-based PVI (P = 1.00), procedural duration (P = 0.95), procedural complications (P = 0.607), fluoroscopic time (P = 0.36), and fluoroscopic dose (P = 0.16). The use of the novel KODEX-EPD mapping system in the cryoablation procedure was associated with a significant reduction of the volume of contrast medium use and the recurrence rate compared with the conventional cryoablation while preserving similar efficacy, safety profile, and procedure time.

Percutaneous Cryoablation of Recurrent or Oligometastatic Tumors in Thoracoabdominal Soft Tissues: Safety, Effectiveness, and Technical Aspects

PurposeTo assess the effectiveness and safety of cryoablation (CRA) for the treatment of recurrent or oligometastatic solid tumors located in the thoracoabdominal soft tissues. Materials and MethodsTwenty-two percutaneous CRA procedures performed in 19 patients to treat recurrent or oligometastatic tumors in thoracoabdominal soft tissue were retrospectively examined. All procedures were performed between January 2015 and June 2021 under ultrasound and computed tomography (CT) guidance, and the most complex procedures were performed with CT-based navigation systems. The histology of the primary tumors included colorectal adenocarcinoma, squamous cell lung carcinoma, pancreatic adenocarcinoma, renal cell carcinoma, and hepatocellular carcinoma. Adverse events, technical success, and local tumor control were analyzed. ResultsThe mean age of the patients was 66.5 years, with a mean tumor size of 24.8 mm. The mean time of the procedures was 68 minutes, with a mean number of 2.5 cryoprobes used. Hydrodissection was performed in 63% of the procedures to protect the surrounding anatomical structures. The mean size of the ice ball, measured on axial CT scans at the end of the procedures, was 43.5 mm. No severe adverse events were observed. Technical success was achieved in all cases. Three patients experienced local tumor progression (2 residual disease and 1 recurrence), which were successfully treated with a second CRA procedure. ConclusionsPercutaneous CRA is a safe and effective therapy in selected cases of recurrent or oligometastatic tumors in the thoracoabdominal soft tissues.

Chinese expert consensus on perioperative management of renal tumor cryoablation (2022 edition)

In recent years, the incidence of renal cancer has been increasing continuously. Surgical resection is the "gold standard" for the treatment of small renal cancer. However, local ablation therapy of renal cancer is undoubtedly the best choice for patients with short life expectancy, other complications, and impaired renal function who are not suitable for surgery. In recent years, with the development of ablation techniques and long-term follow-up, local ablation has shown good therapeutic effects. As many domestic hospitals are performing or planning to perform renal tumor cryoablation to improve the clinical cure rate and surgical safety of renal tumor cryoablation, it is necessary to standardize the surgical indications, contraindications, perioperative management, efficacy evaluation, and other common problems. Currently, there is no expert consensus regarding perioperative renal tumor cryoablation in China. To standardize the perioperative management of renal tumor cryoablation and related technical operations in clinical practice, and improve the effectiveness and safety of cryoablation, the expert committee of Tumor Interventional and Minimally Invasive Diagnosis and Treatment Continuing Education Base of the Chinese Anti-Cancer Association convened experts in related fields to discuss and formulate this consensus, which is hereby published, for clinical reference and application.

Investigation of the efficacy and safety of cryoablation and intra-arterial PD-1 inhibitor in patients with advanced disease not responding to checkpoint inhibitors: An exploratory study.

ObjectiveTo explore the effectiveness of cryoablation combined with arterial perfusion with programmed cell death protein 1 inhibitors in overcoming immune resistance in advanced solid cancers.MethodsIn this pilot retrospective study, nine patients with solid cancers were treated with tumour cryoablation and arterial perfusion with programmed cell death protein 1 inhibitors, which had previously proven ineffective. The CIBERSORT software was used to estimate the levels of tumour-infiltrating immune cells in the challenged tumour. Changes in the levels of circulating T cells were assessed using flow cytometry. The primary endpoints were disease control and objective response rates, and the secondary endpoint was safety.ResultsThe nine patients with advanced solid tumours received cryoablation combined with arterial perfusion with programmed cell death protein 1 inhibitors between June and December 2021. The median follow-up time was 5.8 months. We recorded an objective response rate in two patients (22.22%). The best overall responses were partial responses in two patients (22.22%) and one case (11.11%) of stable disease, while six patients (66.67%) presented progressive disease. However, the median overall survival time was not reached. The median progression-free survival was 2.4 months. Treatment-related severe adverse events included one case of abdominal infection and one case of upper gastrointestinal bleeding, which were cured after the intervention. The CIBERSORT software confirmed the importance of cryoablation in regulating tumour-infiltrating immune cells. Thus, macrophage polarisation from the M2 to the M1 phenotype in the challenged tumour and a gradual increase in the levels of circulating CD4+ T cells were observed after administration of the combination therapy.ConclusionCryoablation combined with arterial perfusion with programmed cell death protein 1 inhibitors has the potential efficacy and safety to overcome immune resistance in patients with advanced solid cancers. The combination therapy leads to macrophage polarisation from the M2 to the M1 phenotype in the challenged tumour to enhance antitumour immunity.

Cryoablation of Soft Tissues Low-Flow Vascular Malformations: Clinical Outcomes and Safety.

To report the clinical effectiveness and the safety of cryoablation in first or second-line therapy in symptomatic soft tissues vascular malformation, a mini-invasive therapeutic alternative to sclerotherapy or surgery. This retrospective and monocentric study included patients with symptomatic low-flow vascular malformation. The interventions were carried out under computed tomography (CT) scan, Cone-beam CT (CBCT) and/or USA guidance. Clinical response was evaluated by collecting the Numerical Rating Scale (NRS) for symptoms before and after the ablation. Safety was assessed based on criteria proposed by the Cardiovascular and Interventional Radiological Society of Europe. Imaging response was evaluated with post-ablation Magnetic Resonance Imaging. Twenty-one patients were included. Cryoablation was the first operative treatment for 12 patients (12/21, 57%). The remaining patients had already undergone surgery (2/21, 9%) or one or more sclerotherapy procedures (7/21, 33%).Symptoms assessed by Numerical Rating Scale dropped from a median of 7 [IQR 6-8] before the procedure to a median of 1 [IQR 0-2] after cryoablation (p < 0.001). Half of the patients declared a full effectiveness of cryoablation on their symptoms (11/21). No major complications and four minor adverse events (two skin lesions, two patients with neuropathic pain) were reported (19%). Lesional volume significantly decreased after cryoablation (median from 3.7 cm3 [1-10.4] to 0.25 cm3 [0-2.0], p < 0.001). Cryoablation seems to be a safe and effective first- or second-line therapy for soft tissue vascular malformations.

Abstract No. 62 Percutaneous ablation of renal cell carcinoma: a comparative study of effectiveness and safety of cryoablation and microwave ablation

Abstract No. 62 Percutaneous ablation of renal cell carcinoma: a comparative study of effectiveness and safety of cryoablation and microwave ablation

Effectiveness and Safety of Cryoablation in Patients With Atrial Fibrillation Episodes of

Background: Paroxysmal atrial fibrillation (AF) is closely related to pathophysiologic processes and clinical outcomes. However, it is uncertain whether cryoablation of pulmonary veins isolation is effective and safe for patients with symptomatic and drug refractory AF episodes of <24-h duration.Methods: The patients were designed into Group A (253 patients with paroxysmal AF episodes of <24-h duration) and Group B (253 patients with paroxysmal AF lasting for 24 h or longer) on a 1:1 basis by identical propensity scores. Mortality, stroke/transient ischemic attack (TIA), and complications relevant to the cryoablation procedure were compared, and recurrence of atrial tachyarrhythmia was analyzed for clinical independent predictors.Results: The rate of atrial tachyarrhythmia recurrence was 21.74% in Group A and 30.04% in Group B, respectively (P = 0.042). At 12-month follow-up from the procedure, lower incidences of stroke/TIA endpoint of the patients were observed in Group A compared with Group B by Kaplan–Meier analysis [HR 0.34 (0.13–0.87), P = 0.025]. No significant differences in mortality and complications relevant to the cryoablation procedure were observed between Group A and Group B. Moreover, adjusted multivariable Cox regression analysis showed that <24-h paroxysmal AF type (HR 0.644, 95% CI: 0.455–0.913, P = 0.014) and left atrium diameter (LAD) (>40 mm) (HR 1.696, 95% CI: 1.046–2.750, P = 0.032) were independently associated with the incidence of recurrence of atrial tachyarrhythmia in the study.Conclusion: Our findings indicated that <24-h paroxysmal AF type was obviously associated with an increased success rate of cryoablation and reduced incidence of stroke/TIA during the follow-up period. Therefore, there is superior effectiveness and similar safety in patients with AF episodes of <24-h duration compared with patients with longer paroxysmal AF duration.

Is balloon cryoablation effective in common pulmonary trunk?

Abstract Introduction Common pulmonary trunk (CPT) accounts for the most frequent pulmonary vein anatomical variation. The most frequent technique used for pulmonary vein isolation (PVI) is point-by-point radiofrequency, using cryoablation (CB) is still debatable. Some few studies have shown the feasibility and safety of CB in CPT atrial fibrillation (AF) patients (pts), most of them performed angio-CT prior to ablation. Purpose To analyzed AF pts with and without CPT submitted to CB in regarding of success rate and safety. Methods Single-center retrospective study of consecutive AF pts refractory to antiarrhythmics submitted to CB between 2017 and 2020. Before the procedure auriculography was performed in all pts to verify variations in pulmonary veins, however the procedure was not modify regarding the presence of CPT. Clinical records were analyzed to determine baseline characteristics, success rate and complications. Monitoring was performed with a 7-day event loop recorder at 3, 6 and 12 months and annually from the 2nd year. Success was defined by recurrence of AF (duration &amp;gt;30 seconds). Kaplan Meier survival curves were used to estimate the risk of events and the groups were compared using Chi-square and Mann-Whitney analysis. Results A total of 232 pts (60±12 years, 68% males) underwent CB. 29 pts had CPT (28 – common left pulmonary trunk and 2 – common right pulmonary trunk). Baseline characteristics were similar between groups, except for CHA2DS2VASc score and prior cerebrovascular disease history which were higher in CPT pts (3±2 vs 2±2, p=0.001; 24.1% vs 6.8%, p=0.007, respectively). The mean baseline CHA2DS2VASc was 2±2 and the median post-CB follow-up was 135 (IQ 32–249) days. Both the 1 and 3 year arrhythmic recurrence after AF ablation was not significantly different when comparing CPT and non CPT group with a 3 year success rate of 95.8% in pts with CPV against 86.5% in pts without CPT (p=0.299). There was no difference between groups (p=0.296; p=0,164, respectively) regarding the time of the procedure, radiation dose and rate of complications. Conclusions In our experience, balloon cryoablation for PVI is a safe and successful procedure in patients with CPT anatomical variation. Funding Acknowledgement Type of funding sources: None.

A Single-Center 10-Year Retrospective Analysis of Cryoablation for the Management of Desmoid Tumors

PurposeTo determine the efficacy and safety of cryoablation in patients with desmoid tumors (DTs) retrospectively over a 10-year period at a single institution. Materials and MethodsBetween February 25, 2010, and February 25, 2020, 25 patients (age, 12–80 years) with 26 lesions (mean preprocedural tumor volume was 237 cm3) were treated over 44 cryoablation procedures. Eleven patients were treated with first-line therapy. Fourteen patients had previous medical therapy, radiotherapy, and/or surgery. Subsequent clinical follow-up, imaging outcomes, and safety were analyzed for technical success, change in total lesion volume (TLV) and viable tumor volume (VTV), modified response evaluation criteria in solid tumors (mRECIST), progression-free survival (PFS) for tumor progression and symptom recurrence, symptom improvement, and procedure-related complications. Symptomatic improvement was defined as documentation of relief of pain (partial or complete) and/or functional impairment. ResultsAll procedures were technically successful. At 7–12 months, median changes in TLV and VTV were −6.7% (P = .809) and −43.7% (P = .01), respectively. At 10–12 months, the mRECIST responses were complete response, 0%; partial response, 61.5% (8/13); stable disease, 30.8% (4/13); and progressive disease, 7.7% (1/13). The median PFS for tumor progression and symptom recurrence were not reached, with a median follow-up of 15.3 and 21.0 months, respectively. Symptomatic relief (partial or complete) was achieved in 96.9% (32/33) of patients. One major complication was noted (2.4%). ConclusionsIn this retrospectively identified cohort, cryoablation was effective and safe for the local control of extra-abdominal DTs in short-term follow-up.

Cryoablation for advanced non-small cell lung cancer: a protocol for a systematic review

IntroductionNational Comprehensive Cancer Network has recommended cryoablation to replace the resection in the treatment of medically operable non-small cell lung cancer (NSCLC). Cryoablation also has been used for the advanced...

Feasibility and safety of cryoablation on the porcine ureter using a new balloon cryoprobe

Cryoablation, as a well-characterized technology, has multifarious clinical applications. But few are reported on ureteral endometriosis. Thus, we examined the feasibility and safety of cryotherapy with a novel balloon cryoprobe on ureter in a live porcine model. During the freezing and thawing cycle, temperature was recorded in different parts of the ureter in real-time. Two-minute cryoablation could induce necrosis within range in 1 cm diameter on serosa layer. The temperature respectively dropped to −136.5 °C, −96.1 °C and −17.5 °C at the cryotherapy center, 1 cm and 1.5 cm from center on serosal side. The ureters were harvested immediately, 2 weeks or 3 months after cryotherapy. No perforation, stricture, adhesions, or hydronephrosis was observed. Histopathologic representations of ureters after cryoablation indicated that full thickness necroses of ureters were seen in all samples. The results demonstrated ureteral cryoablation using a novel balloon probe was feasible, safe, and effective. These findings provided us reference before cryoablation could be applied in clinical practice in treating ureteral endometriosis.

Risk of atrioesophageal fistula with cryoballoon ablation of atrial fibrillation.

BackgroundAlthough there are considerable data on the safety of cryoablation, data on the rare but severe complication of atrioesophageal fistula (AEF) following cryoballoon ablation are limited.ObjectiveTo report the global, user-reported incidence of AEF associated with cryoballoon ablation for the treatment of atrial fibrillation using Medtronic’s complaint database.MethodsUser-reported cryoballoon ablation complications occurring between July 1, 2009, and March 31, 2019, were reviewed to identify cases of AEF. A global event rate of AEF was calculated by dividing the event count by total catheter utilization over the same period. Data on symptoms and patient sequalae were reported as available.ResultsMore than 500,000 Arctic Front cryoballoon catheters (Arctic Front, Arctic Front Advance, Arctic Front Advance ST, and Arctic Front Advance Pro; Medtronic, Inc) were distributed globally during the 9.75-year study period. During this time, 18 confirmed AEF, 1 suspected AEF, and 1 pericardial esophageal fistula were identified; therefore, global incidence of AEF associated with the Arctic Front family of ablation catheters was 0.00396%. Patients most commonly presented with fever (88.2%), and initial symptoms were reported a median of 21 (interquartile range: 4–30) days after the ablation. Although rare, the development of an AEF resulted in death in 68.8% (11/16) of patients with known outcomes.ConclusionsAEF is a possible but rare complication of cryoballoon ablation with a reported frequency of 1 in every 25,000 patients treated. Awareness of the prevalence and manifestation of AEF associated with cryoballoon ablation is critical for early identification and treatment of this complication.

Abstract No. 508 Recalcitrant aneurysmal bone cysts: does cryoablation help?

Aneurysmal bone cysts (ABC) are most commonly seen in children and can be very aggressive and locally destructive. The described treatments for ABCs are curettage, resection, intracystic steroid injections, arterial embolization and sclerotherapy. The recurrence rate after traditional surgical treatments ranges from 12% to 71% (71% in children<10 years) with 90% detected within 2 years of surgical treatment. Response to sclerotherapy is gradual, unpredictable and may also fail. Several sessions of percutaneous sclerotherapy is often needed to gain control over rapidly progressive ABCs. We studied the efficacy and safety of cryoablation as a novel approach in treating resistant, rapidly progressive or relapsed ABCs. Eight patients (4 yr to 23 yr (mean 13.7 yr); 5 female pts) with symptomatic and recurrent progressive ABCs post percutaneous sclerotherapy and/or surgical resection underwent percutaneous image-guided cryoablation. ABCs were expansile, aggressive appearing on imaging and in challenging locations: fibula (n=3), tibia (n=2), pelvic bones (n=2), metacarpal (n=1). Patients were evaluated by the orthopedics and interventional radiology before being referred for cryoablation. Percutaneous image-guided (ultrasound and cone-beam CT) cryoablation was performed using Argon and Helium gases in a single or staged sessions. Neuromonitoring was used when lesion was close to major nerves. Pre procedure and follow up clinical and imaging evaluation was done to assess outcome. Following cryoablation, there was significant improvement in symptoms with tumor size regression and bone stabilization in all patients followed over 6 months to 3 years. Two patients had transient nerve injury which self-resolved. Percutaneous image-guided cryoablation is an effective novel modality to treat challenging and recalcitrant aneurysmal bone cysts and should be considered early in such cases.

Safety and efficacy of cryoablation vs. radiofrequency ablation of septal accessory pathways: systematic review of the literature and meta-analyses.

Radiofrequency ablation (RFA) of septal accessory pathways (APs) is associated with a significant rate of first procedure failures and complications. Cryoablation is an alternative energy source but there are no studies comparing both ablation techniques. We aimed to systematically review the literature and compare the efficacy and safety of cryoablation vs. RFA of septal APs. We conducted two separate meta-analysis of cryoablation and RFA of septal APs and calculated the global estimates of the efficacy and safety. Sixty-four articles were included: 38 articles reporting RFA and 27 articles reporting cryoablation procedures. Additionally, we included the previously non-published cryoablation registry of septal APs performed at our institution. Overall, 4244 septal APs constitute our study population, 3495 in the RFA cohort and 749 in the cryoablation cohort. Acute procedural success rate of cryoablation was 86.0% (95% CI 81.6-89.4%) and RFA 89.0% (95% CI 86.8-91.0%). Recurrence rate of cryoablation was 18.1% (95% CI 14.8-21.8%) and RFA 9.9% (95% CI 8.2-12.0%). Long-term success rate after multiple ablation procedures of cryoablation was 75.9% (95% CI 68.2-82.3%) and RFA 88.4% (95% CI 84.7-91.3%). There were no reported cases of persistent atrioventricular block (AVB) with cryoablation and 2.7% (95% CI 2.2-3.4%) with RFA. Studies of RFA for treatment of septal APs report higher efficacy rates than do studies using cryoablation, but a significantly higher rate of AVB.

The feasibility and safety of cryoablation as an adjuvant therapy with transurethral resection of bladder tumor: A pilot study

BackgroundThe potential for transurethral resection (TUR) to result in residual tumors in patients with muscle invasive or high-risk non-muscle invasive bladder cancer (NMIBC) may affect local recurrence or progression. This study attempted to evaluate the feasibility and safety of cryoablation as an adjuvant therapy with TUR to treat bladder tumor. MethodsPatients who met inclusion criteria between December 2014 and August 2015 in our institute was included. The inclusion criteria were as followed: 1) urothelial carcinoma; 2) non-muscle-invasive bladder cancer or 3) stage T2 muscle invasive bladder cancer meeting with the following two conditions, solitary and less than 3 cm in size. Ten patients underwent TUR followed by immediate transurethral cryoablation of the tumor resection bed. All patients underwent pathological re-evaluation during follow-up cystoscopy. ResultsThe cryoablation was successfully performed without bladder perforation during the procedures. No grade II–V complications were observed. Among these patients, two had T2a stage tumors, three had T1 stage tumors and five had Ta stage tumors. The median follow-up of cases was 9 months (range 9–14 months). During follow-up, tumor recurrence was observed in three patients. Only one recurrence occurred in the primary tumor site. ConclusionsCryoablation as an adjuvant therapy with TUR for bladder tumors was feasible and safe. The potential benefit was to eliminate the residual tumor to the greatest extent.

Efficacy of cryoablation combined with zoledronic acid sequential therapy for bone metastases pain

Objective To investigate the clinical efficacy and safety of cryoablation combined with zoledronic acid sequential therapy for bone metastases pain. Methods Twenty-four patients from our department suffering from malignant tumors with moderate to severe pain due to bone metastases were enrolled in this study. Those patients with 28 metastatic bone tumors were successfully treated with cryoablation operations under CT-guided. Three days after cryoablation they were offered zoledronic acid (4 mg added in 100 ml normal saline, dripping for more than 15 min), once 4 weeks. Pain level and life quality were respectively evaluated by NRS (Numerical rating scale) and KPS (Karnofsky performance status), before cryoablation, 3 days after cryoablation, 2 weeks and 12 weeks after zoledronic acid sequential therapy. Results Without serious complications, all of 24 patients were successfully punctured to tumor lesions. Patients’ pain scores were 7.70±0.86 (before cryoablation), 3.29±0.95 (3 d after cryoablation), 2.54±0.83 (2 weeks after zoledronic acid sequential therapy) and 2.17±0.76 (12 weeks after zoledronic acid sequential therapy), with a significant statistical difference between pretherapy and post-treatment (F=530.64, P<0.001); during observation period after treatment, the effective rate in pain was 91.67%. KPS scores were 45.83±6.54 (before cryoablation), 49.58±6.24 (3 d after cryoablation), 61.67±7.01 (2 weeks after zoledronic acid sequential therapy) and 78.33±8.68 (12 weeks after zoledronic acid sequential therapy), with a significant statistical difference between pretherapy and post-treatment (F=418.99, P<0.001); during observation period after treatment, the effective rate in KPS was 75.00%. Six months after the treatment, there were 10 cases of CR, 11 cases of PR, and the effective rate was 87.50%. Conclusion Cryoablation combined with zoledronic acid may be an effective therapeutic method with good safety in the treatment of patients with bone metastases pain. Key words: Cryosurgery; Neoplasm metastases; Pain; Bisphosphonates

Abstract 19678: Safety of Cryoablation of Atrial Fibrillation in the Presence of Mechanical Mitral Valve

Introduction: Pulmonary vein isolation is an effective therapy for recurrent, symptomatic, drug-refractory atrial fibrillation (AF). Radiofrequency ablation (RFA) has long been the standard of care, while cryoballoon technology has emerged as a feasible approach with promising results in paroxysmal AF. There is risk of catheter entrapment during RFA in patients with mechanical mitral valve and the experience is limited. To the best of our knowledge pulmonary vein isolation (PVI) with cryoablation has never been reported in a patient with a mechanical mitral valve. Case: A 52 year old male presented with symptomatic paroxysmal AF, nonischemic cardiomyopathy biventricular defibrillator, mechanical aortic and mitral valve replacement for rheumatic valvular disease. The patient was highly symptomatic while on sotalol therapy. We proceeded with PVI using cryoablation technology. Procedure: After a single transseptal puncture, a 28 mm cryoballoon catheter and 20mm 8 pole circular recording catheter were advanced into the left atrium. All four pulmonary veins were isolated with the aid of intracardiac echo, fluoroscopy and Ensite 3-D mapping. Caution was maintained to minimize catheter manipulation and to keep the catheters away from the mechanical valvular plane. Discussion: The use of cryoablation for PVI has several potential advantages over radiofrequency ablation including greater improvement in fluoroscopic time and total procedure duration. The risk of prosthetic valve dysfunction due to trauma from ablation catheter, and entrapment of the circular mapping catheter in the mitral valve apparatus represent major concerns when performing PVI in patients with mitral valve replacement, however, less need for manipulation of catheter is an advantage of cryoablation compared to RFA in this case. This case illustrates that cryoablation can be successfully performed in a patient with a prosthetic mechanical mitral valve.

Cryoablation of septal accessory pathways in children: midterm results.

Radiofrequency (RF) catheter ablation in the septal arrhythmia substrates has an increased risk of irreversible atrioventricular block. Despite its safety profile, several studies reported a lower acute success rate and a higher recurrence rate with cryoablation of septal accessory pathways (APs) when compared to RF ablation. The aim of this study was to assess the efficacy and safety of cryoablation of right septal APs using an electroanatomical mapping system guidance. A total of 43 consecutive patients (13.2 ± 5.5 years) underwent cryoablation for right septal APs. The EnSite system (St. Jude Medical, St. Paul, MN, USA) was used in all procedures. No fluoroscopy was used in 90% of patients (39/43). The mean fluoroscopy time in the remaining four patients was 3.7 ± 0.7 minutes. An electrophysiology catheter with 2-mm distal spacing was used to determine the precise AP location. The majority of the patients (20/43) had anteroseptal, and remaining of the patients had posteroseptal (15/43) and midseptal (8/43) APs. A 6-mm-tip catheter was used in 33 patients and 8-mm-tip catheter was used in nine patients (both catheters were used in one patient). The mean procedure duration and number of complete cryoablation lesions were 181.5 ± 60.6 minutes and 6.1 ± 3.1 minutes, respectively. Acute success was achieved in 40 of 43 patients (93%). No complications were noted. During a mean follow-up of 8.8 ± 4.8 months, five patients (12.5%) experienced recurrence. Our data suggest that cryoablation of septal APs can be performed safely with comparable efficacy to the reported RF ablation results using a limited fluoroscopy approach.

Cryoablation combined with zoledronic acid in comparison with cryoablation and zoledronic acid alone in the treatment of painful bone metastases.

This study aimed to examine the efficacy and safety of cryoablation, combined with zoledronic acid or alone, in the treatment of bone metastatic pain. A total of 84 patients were randomly divided into three groups: group A (cryoablation plus zoledronic acid), group B (cryoablation) and group C (zoledronic acid). In group A, the overall response [OR = complete response (CR) + partial response (PR)] was 85.7% (24/28), the CR was 35.7% (10/28) and the PR was 50.0% (14/28). In group B, the OR was 50.0% (14/28), the CR was 14.3% (4/28) and the PR was 35.7% (10/28). In group C, the OR was 67.9% (19/28), the CR was 21.4% (6/28) and the PR was 46.4% (13/28). The differences in OR, CR and PR among the three groups were statistically significant (P<0.05). The mean onset time of pain relief for the cryoablation combined with zoledronic acid treatment group was 1.96±2.26 days, for cryoablation treatment alone was 1.43±1.79 days and for zoledronic acid alone was 11.67±3.14 days; there were statistically significant differences among the three groups (P<0.05). The response duration was 146.68±1.89 days in group A, 71.60±2.94 days in group B and 112.99±1.37 days in group C; the differences among the three groups were statistically significant (P<0.01). In conclusion, cryoablation combined with zoledronic acid is an effective and safe therapeutic strategy for the treatment of bone metastatic pain.