Cryoballoon-based Pulmonary Vein Isolation Research Articles

Pulsed-field- vs. cryoballoon-based pulmonary vein isolation: lessons from repeat procedures.

Pulsed-field ablation (PFA) is an emerging technology to perform pulmonary vein isolation (PVI). Initial data demonstrated high safety and efficacy. Data on long-term PVI durability and reconduction patterns in comparison to established energy sources for PVI are scarce. We compare findings in repeat ablation procedures after a first PFA to findings in repeat ablation procedures after a first cryoballoon ablation (CBA) based PVI. A total of 550 consecutively enrolled patients underwent PFA or CBA index PVI. Repeat ablations in patients with symptomatic atrial arrhythmia recurrences were analysed. A total of 22/191 (12%) patients after index PFA-PVI and 44/359 (12%) after CBA-PVI underwent repeat ablation. Reconduction of any pulmonary vein (PV) was detected by multipolar spiral mapping catheter at each PV with careful evaluation of PV potentials and by 3D-mapping in 16/22 patients (73%) after PFA-PVI and in 33/44 (75%) after CBA-PVI (P = 1.000). Of 82 initially isolated PVs after PFA-PVI, 31 (38%) were reconducting; of 169 isolated PVs after CBA-PVI, 63 (37%) were reconducting (P = 0.936). Clinical atrial tachycardia occurred similarly in patients after PFA (5/22; 23%) and CBA (7/44; 16%; P = 0.515). Roof lines were set more often after PFA- (8/22; 36%) compared with CBA-PVI (5/44; 11%; P = 0.023). Repeat procedure duration [PFA: 87 (76, 123) min; CBA: 93 (75, 128) min; P = 0.446] was similar and fluoroscopy time [PFA: 11 (9, 14) min; CBA: 11 (8, 14) min; P = 0.739] equal between groups at repeat ablation. During repeat ablation after previous PFA- or CBA-based PVI, electrical PV-reconduction rates and patterns were similar.

Pulmonary vein reconnection and repeat ablation characteristics following cryoballoon-compared to radiofrequency-based pulmonary vein isolation.

Despite advances in efficacy and safety of pulmonary vein isolation (PVI), atrial fibrillation (AF) recurrence after PVI remains common. PV-reconnection is the main finding during repeat PVI procedures performed to treat recurrent AF. To analyze pulmonary vein (PV) reconnection patterns during repeat ablation procedures in a large cohort of consecutive patients undergoing radio frequency or cryoballoon-based PVI. Retrospective analysis of PV-reconnection patterns and analysis of re-ablation strategies in consecutive index RF- and CB-based PVI and their respective re-ablation procedures during concomitant usage of both energy sources at a single high-volume center in Germany. A total of 610 first (06/2015-10/2022) and 133 s (01/2016-11/2022) repeat ablation procedures after 363 (60%) RF- and 247 (40%) CB-based index PVIs between 01/2015 and 12/2021 were analyzed. PV-reconnection was found in 509/610 (83%) patients at first and 74/133 (56%) patients at second repeat procedure. 465 of 968 (48%) initially via CB isolated PVs were reconnected at first re-ablation but 796 of 1422 initially RF-isolated PV (56%) were reconnected (OR: 0.73 [95% CI: 0.62-0.86]; p < .001). This was driven by fewer reconnections of the left PVs (LSPV: OR: 0.60 [95% CI: 0.42-0.86]; p = .005 and LSPV: 0.67 [0.47-0.95]; p = .026). PV-reconnection was more likely after longer, RF-based index PVI and in older females. Repeat procedures were shorter after CB-compared to after RF-PVI. Reconnection remains the most common reason for repeat AF ablation procedures after PVI. Our data suggest to preferentially use of the cryoballoon during index PVI, especially in older women.

Pulsed-field vs. cryo-balloon based pulmonary vein isolation: does reduced autonomic modulation effect freedom of atrial fibrillation?

Abstract Background Pulsed-field ablation (PFA) is a new energy source integrated into single-shot devices enabling pulmonary vein isolation (PVI) during atrial fibrillation (AF) ablation. It has been demonstrated that PFA is noninferior to conventional thermal ablation. Conceptually, PFA preferentially damages cardiomyocytes and our prior data show that PFA causes less damage to neuronal tissue and reduced autonomic dysfunction than CBA. Here, we analyzed heart rate variability (HRV) as an additional parameter of intracardiac nervous system and whether the damage to neuronal tissue quantified by biomarker release and functional parameters might influence the recurrence rate of atrial fibrillation in PFA and CBA treated patients. Methods We prospectively included consecutive patients with paroxysmal AF undergoing index PVI applying PFA (n=65) or CBA (n=112). We quantified the ablation-dependent effect on intracardiac autonomic nervous system by comparing resting heart rate (HR), HRV and circulating concentrations of the neuronal biomarker S100B. Recurrent AF was detected using Holter ECGs, wearables and telephone interviews. Results Baseline characteristics did not differ between PFA and CBA (age 66 vs. 68 years, female 33% vs. 39%, CHADS-VASc Score 2.1 vs. 2.2, indexed LA volume 32 vs. 31 ml/m², BMI 27.3 vs. 27.4 kg/m²). After CBA-based PVI, HR increased (pre 63 vs. post 70 bpm, p&amp;lt;0.001) and HRV decreased (SDNN pre 54 vs. post 26 ms, p=0.007). After PFA-based PVI, HR and HRV remained stable (HR pre 63 vs. 64 bpm, p=0.591; HRV SDNN pre 37 vs. post 36 ms, p=0.890). In a direct comparison, the HR-increase and HRV-decrease observed after CBA-based PVI was significant compared to PFA (0.8 vs. 7.3 bpm, p&amp;lt;0.001 and SDNN -1 vs. 29 ms, p=0.003). We reported previously that PFA induced less S100B release (28 ng/dl) than CBA (68 ng/dl, p&amp;lt;0.001) and that PV reconnection rates in ReDo procedure were similar between PFA (40%) and CBA (40%). 1 year follow-up revealed freedom of AF in 79% after PFA and 73% after CBA (p=0.230). Dividing patients in upper and lower half of HR increase and S100B release after PVI, patients showed no difference in recurrence rates after CBA. Conclusion These data suggest that neurocardiac damage near the pulmonary veins seems not to contribute to freedom of AF recurrences after PVI.

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.

A novel saline-based occlusion tool allows for dye-less cryoballoon-based pulmonary vein isolation and fluoroscopy reduction

Abstract Funding Acknowledgements Type of funding sources: None. Background Cryoballoon (CB)- based pulmonary vein isolation (PVI) remains guided by fluoroscopy and dye. The novel saline injection-based occlusion tool allows for pulmonary vein (PV)-occlusion assessment without the need for dye injection. Aim To compare KODEX-EPD guided CB-PVI using the novel saline injection-based workflow with conventional cryoablation for acute efficacy, fluoroscopy exposure and dye volume. Methods Consecutive atrial fibrillation (AF)- patients undergoing CB-PVI in conjunction with KODEX-EPD (CryoEPD group) were analyzed. A left atrial image was created to visualize pulmonary vein (PV) anatomy prior to ablation. PV-occlusion was assessed with the KODEX-EPD occlusion tool along with saline injection. Patients undergoing conventional CB-PVI (CryoCONV group) in the same time period acted as controls. Results One hundred forty patients (91/140 (65%) persistent AF) were studied. Seventy patients underwent CryoEPD procedures (64 ± 13 years, 21 (30%) female) and seventy patients underwent CryoCONV procedures (68 ± 10 years, 27 (39%) female). A total of 560 PVs were identified and successfully isolated. Mean procedure time was 66 ± 15 minutes for the CryoEPD group, and 65 ± 19 minutes for the CryoCONV group (p=0.3). Fluoroscopy time (CryoEPD 6 ± 4 minutes; CryoCONV 13 ± 6 minutes, p&amp;lt;0.001) and dose area product (CryoEPD 193 [111; 297] cGycm2; CryoCONV 381 [268; 614] cGycm2, p&amp;lt;0.001) were lower in patients undergoing CryoEPD compared with CryoCONV procedures. No dye was needed in the CryoEPD group while 53 ± 18 ml dye per patient were administered for the CryoCONV group (p&amp;lt;0.001). The overall complication rate was comparable between both groups (p=0.5). Conclusion KODEX-EPD guided AF-ablation enables dye-free CB-based PVI with reduced fluoroscopy exposure when compared to conventional CB-ablation, without differences in acute procedural outcomes or procedure duration.

A novel saline-based occlusion tool allows for dye-less cryoballoon-based pulmonary vein isolation and fluoroscopy reduction.

Cryoballoon (CB)- based pulmonary vein isolation (PVI) remains guided by fluoroscopy and dye. The novel saline injection-based occlusion tool allows for pulmonary vein (PV)-occlusion assessment without the need for dye injection. To compare KODEX-EPD guided CB-PVI using the novel saline injection-based workflow with conventional cryoablation for acute efficacy, fluoroscopy exposure and dye volume. Consecutive atrial fibrillation (AF)- patients undergoing CB-PVI in conjunction with KODEX-EPD (CryoEPD group) were analyzed. Patients undergoing conventional CB-PVI (Cryo group) in the same time period acted as controls. One hundred forty patients [91/140 (65%) persistent AF] were studied. Seventy patients underwent CryoEPD procedures [64 ± 13 years, 21 (30%) female] and seventy patients underwent Cryo procedures [68 ± 10 years, 27 (39%) female].A total of 560 PVs were identified and successfully isolated. Mean procedure time was 66 ± 15 min for the CryoEPD group, and 65 ± 19 min for the Cryo group (p = 0.3). Fluoroscopy time (CryoEPD 6 ± 4 min; Cryo 13 ± 6 min, p < 0.001) and dose area product (CryoEPD 193 [111; 297] cGycm2; Cryo 381 [268; 614] cGycm2, p < 0.001) were lower in patients undergoing CryoEPD compared with Cryo procedures. No dye was needed in the CryoEPD group while 53 ± 18 ml dye per patient were administered for the Cryo group (p < 0.001). The overall complication rate was comparable between both groups (p = 0.5). KODEX-EPD guided AF-ablation enables dye-free CB-based PVI with reduced fluoroscopy exposure when compared to conventional CB-ablation, without differences in acute procedural outcomes or procedure duration.

Association of left atrial enlargement and increased left ventricular wall thickness with arrhythmia recurrence after cryoballoon ablation for atrial fibrillation.

Left atrial enlargement (LAE) predicts atrial fibrillation (AF) recurrence after cryoballoon-based pulmonary vein isolation (CB). Increased left ventricular wall thickness (LVWT) is pathophysiologically associated with LAE and atrial arrhythmias. To assess effect of increased LVWT on long-term outcomes of CB depending on coexistence of LAE. LAE was defined using either echocardiography ( > 48 cm³/m²) or multislice computer tomography (MSCT, ≥63 cm³/m²). Increased LVWT was echocardiographic septal/posterior wall thickness > 10 mm in males and > 9 mm in females. All patients achieved 2-year follow-up. Of 250 patients (median [interquartile range, IQR] age of 61 [49.0-67.3] years; 30% female) with AF (40% non-paroxysmal), 66.5% had hypertension, and 27.2% underwent redo procedure. MSCT was done in 76%. During follow-up of 24.5 (IQR, 6.0-31.00) months the clinical success rate was 72%, despite 46% of patients having arrhythmia recurrence. Arrhythmia recurrence risk was increased by LAE and increased LVWT (hazard ratio [HR], 1.801; P = 0.002 and HR, 1.495; P = 0.036; respectively). The highest arrhythmia recurrence (61.9% at 2 years) was among patients with LAE and increased LVWT (33.6% of patients); intermediate (41.8%) among patients with isolated LAE; and lowest among patients with isolated increased LVWT or patients without LAE or increased LVWT (36.8% and 35.2% respectively, P = 0.004). After adjustment for body mass index (BMI), paroxysmal AF, CHA₂DS₂-VASc score, clinically-significant valvular heart disease, and cardiomyopathy, patients with LAE and concomitant increased LVWT diagnosis had a 1.8-times increased risk of arrhythmia recurrence (HR, 1.784; 95% confidence interval [CI], 1.017-3.130; P = 0.043). Joint occurrence of LAE and increased LVWT is associated with the highest rate of arrhythmia recurrence after CB for AF.

Clinical outcomes of cryoballoon ablation for pulmonary vein isolation: Impact of intraprocedural heart rhythm.

BackgroundThe current study sought to assess the impact of the intraprocedural heart rhythm (sinus rhythm [SR] vs. atrial fibrillation [AF]) on acute procedural characteristics, durability of pulmonary vein isolation (PVI) and long-term clinical outcomes of cryoballoon (CB) ablation.MethodsA total of 195 patients with symptomatic paroxysmal (n = 136) or persistent AF (n = 59) underwent CB-based PVI. Ablation procedures were either performed in SR (SR group; n = 147) or during AF (AF group; n = 48). Persistent AF was more frequent in the AF group than in the SR group (62% vs. 20%). All other patient baseline characteristics did not differ between the two groups.ResultsThe nadir temperature during the CB applications was significantly lower in the AF group than in patients in the SR group (−49 [interquartile range, −44; −54]°C vs. −47 [−42; −52]°C, p = 0.002). Median procedure and fluoroscopy times as well as the rate of real-time recordings were not different between the two groups. Repeat ablation for the treatment of atrial arrhythmia recurrence was performed in 60 patients (SR: 44 [30%] patients; AF: 16 [33%] patients), with a trend towards a lower rate of pulmonary vein reconnections in the AF group (p = 0.07). There was no difference in 3-year arrhythmia-free survival (p = 0.8).ConclusionsCryoballoon-based PVI during AF results in lower nadir balloon temperatures and a trend towards a higher durability of PVI as compared to procedures performed in SR. The rate of real-time PVI recordings was not affected by the intraprocedural heart rhythm.

Shortened fluoroscopy duration and reduced use of contrast dye in cryoballoon-based pulmonary vein isolation procedures using KODEX-EPD’s novel occlusion tool

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Study grant by EPD Solutions, Philips, Netherlands Background The occlusion tool was recently introduced for KODEX-EPD which is a novel dielectric high-resolution cardiac imaging system. The occlusion tool provides information about level of pulmonary vein occlusion by the cryoballoon (CB) in CB-based pulmonary vein isolation (PVI) ablation procedures for atrial fibrillation (AF). Purpose Assess effects of the introduction of the occlusion tool on procedural parameters during CB-PVI such as feasibility, acute efficacy and periprocedural safety of KODEX-EPD in different software versions. Methods and Results 173 consecutive patients (60/173 (35%) paroxysmal AF, 64±12 years, 66/173 (38%) female) underwent CB-PVI with EPD imaging between 08/2019 and 10/2021. 38/173 (22%) of all patients were treated using software version 1.4.6, 33/173 (19%) patients with version 1.4.6a, 41/173 (24%) patients with version 1.4.7 and 61/173 (35%) patients with the latest version 1.4.8. Acute PVI was achieved in all patients. No major periprocedural complications were documented. Software version showed significant effects on procedure duration, fluoroscopy duration and dose area product in ANOVA testing (Figure 1A-C). The largest effect in post-hoc testing was observed for fluoroscopy duration (Figure 1B). Tobit regressions were fitted to model effects of software version on the censored variable contrast volume. All software versions predicted used contrast volume (p&amp;lt;0.00748, Figure 1D). Modelling only effects of procedure date on contrast volume was less accurate than for software version (r²=0.057, p for procedure date = 0.0031) and also a Likelihood-Ratio-Test between different regression models underlined significant effects of software version (p&amp;lt;0.0001). Conclusion CB-based PVI in combination with its PV-occlusion tool is feasible and safe. The present data strongly suggests a steady positive development of the novel wide-band dielectric imaging and mapping system towards a fluoroscopy- and dye-reduced CB-based AF-ablation. Software versions were introduced sequentially. Therefore time (procedure date) needs to be considered as the most relevant confounder of the described results (e.g. due to a learning curve using the system). However, differentiated statistical testing could show that the results are mainly explained by software version and only much weaker by procedure date.

Does a Vagal Response Indicate Cardiac Autonomic Modulation and Improve the Therapeutic Effect of Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation? Insights from Cryoballoon Ablation

Background: The incidence and influence of vagal response (VR) observed during cryoballoon-based pulmonary vein isolation (CBA-based PVI) on the cardiac autonomic nervous system (CANS) and ablation outcomes in paroxysmal atrial fibrillation (PAF) remain unknown. Methods: 296 patients were treated with a 28 mm second-generation cryoballoon (Medtronic). A total of 74 patients without structural heart disease and concomitant diseases were chosen for a detailed CANS assessment with a heart rate variability (HRV) analysis. All patients were screened over a 2-year post-ablation period. Results: VR was detected in 30% of patients and included sinus arrest (64%) or severe sinus bradycardia (46%). The presence of VR was not related to PV ostial dimension, patient clinical characteristics or intraprocedural ablation details. CANS modulation, manifesting as increased median HR and decreased HRV parameters with intact sympatho-vagal balance occurred independently of VR presence or absence and sustained for at least 12 months following ablation. VR was not related with more intensive CANS modulation and did not translate into better ablation outcomes when compared to the non-VR group (74% vs. 71% at 12 months and 69% vs. 65% at 24 months respectively). Conclusions: VR is frequent during CBA-based PVI for PAF and unrelated to any additional clinical benefit.

Catheter Ablation for Atrial Fibrillation in Patients ≤30 Years of Age

Pulmonary vein (PV) automaticity is an established trigger for paroxysmal atrial fibrillation (PAF), making PV isolation (PVI) the cornerstone of catheter ablation. However, data on triggers for atrial fibrillation (AF) and catheter ablation strategy in very young patients aged <30 years are sparse. A total of 51 young patients (mean age 24.0 ± 4.2 years, 78.4% men) with drug-refractory PAF underwent electrophysiology (EP) study and ablation at 5 EP centers. None of the patients had structural heart disease or family history of AF. EP study induced supraventricular tachycardia (SVT) in 12 patients (n=12, 23.5%): concealed accessory pathway mediated orthodromic atrioventricular reentrant tachycardia in 3 patients, typical atrioventricular nodal reentrant tachycardia in 6 patients, left superior PV tachycardia in 1 patient, left atrial appendage tachycardia in 1 patient, and typical atrial flutter in 1 patient. In patients with induced SVTs, SVT ablation without PVI was performed as an index procedure, except for the patient with atrial flutter who received cavotricuspid isthmus ablation in addition to PVI. Remaining patients underwent radiofrequency (n=15, 29.4%) or second-generation cryoballoon-based PVI (n=24, 47%). There were no major complications related to ablation procedures. Follow-up was based on outpatient visits including 24-hour Holter-electrocardiogram at 3, 6, and 12 months after ablation, or additional Holter-electrocardiogram was ordered in case of symptoms suggesting recurrence. Recurrence was defined as any atrial tachyarrhythmia (ATA) episode >30 seconds after a 3-month blanking period. A total of 2 patients with atrioventricular nodal reentrant tachycardia, 1 with left atrial appendage tachycardia, experienced AF recurrence within the first 3 months and received PVI. After the 3-month blanking period, during a median follow-up of 17.0 ± 10.1 months, 44 of 51 patients (86.2%) were free of ATA recurrence. In the PVI group, 33 of 39 patients (84.6%) experienced no ATA recurrence. In conclusion, SVT substrate is identified in around a quarter of young adult patients with history of AF, and targeted ablation without PVI may be sufficient in the majority of these patients. PVI is needed in the majority and is safe and effective in this population.

Phrenic Nerve Injury During Cryoballoon-Based Pulmonary Vein Isolation: Results of the Worldwide YETI Registry.

Cryoballoon-based pulmonary vein isolation (PVI) has emerged as an effective treatment for atrial fibrillation. The most frequent complication during cryoballoon-based PVI is phrenic nerve injury (PNI). However, data on PNI are scarce. The YETI registry is a retrospective, multicenter, and multinational registry evaluating the incidence, characteristics, prognostic factors for PNI recovery and follow-up data of patients with PNI during cryoballoon-based PVI. Experienced electrophysiological centers were invited to participate. All patients with PNI during CB2 or third (CB3) and fourth-generation cryoballoon (CB4)-based PVI were eligible. A total of 17 356 patients underwent cryoballoon-based PVI in 33 centers from 10 countries. A total of 731 (4.2%) patients experienced PNI. The mean time to PNI was 127.7±50.4 seconds, and the mean temperature at the time of PNI was -49±8°C. At the end of the procedure, PNI recovered in 394/731 patients (53.9%). Recovery of PNI at 12 months of follow-up was found in 97.0% of patients (682/703, with 28 patients lost to follow-up). A total of 16/703 (2.3%) reported symptomatic PNI. Only 0.06% of the overall population showed symptomatic and permanent PNI. Prognostic factors improving PNI recovery are immediate stop at PNI by double-stop technique and utilization of a bonus-freeze protocol. Age, cryoballoon temperature at PNI, and compound motor action potential amplitude loss >30% were identified as factors decreasing PNI recovery. Based on these parameters, a score was calculated. The YETI score has a numerical value that will directly represent the probability of a specific patient of recovering from PNI within 12 months. The incidence of PNI during cryoballoon-based PVI was 4.2%. Overall 97% of PNI recovered within 12 months. Symptomatic and permanent PNI is exceedingly rare in patients after cryoballoon-based PVI. The YETI score estimates the prognosis after iatrogenic cryoballoon-derived PNI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03645577. Graphic Abstract: A graphic abstract is available for this article.

Accuracy and acute efficacy of a novel occlusion tool to guide cryoballoon-based pulmonary vein isolation

Abstract Background Cryoballoon (CB)-based pulmonary vein isolation (PVI) currently requires to verify occlusion of each pulmonary vein (PV) using fluoroscopy and dye injection. Objective The current study evaluated whether the novel CB-occlusion tool integrated into the wide-band dielectric imaging system KODEX-EPD reliably verifies occlusion of PV according to a novel dye-injection based algorithm. Methods Consecutive patients suffering from symptomatic atrial fibrillation (AF) underwent CB-based PVI using the KODEX-EPD and the novel occlusion-tool (group I). To confirm accurate display of the PVs, selective PV-angiography was performed in the first half of the patients of group I (group Ia) in addition to a three-dimensional left atrial (LA) map using a spiral mapping catheter (Achieve, SMC1, Medtronic, MN, USA). PV-angiographies were waived for the following patients (group Ib). Procedural duration and radiation exposure were compared to a control group of patients undergoing conventional CB-based PVI. Results CB-based PVI was successful in 50/50 patients of group I (mean age 63±11 years, 18 paroxysmal (36%)) and 25/25 patients of group II (66±10 years, 9 paroxysmal (60%)). Concordance of PV-occlusion as assessed by either PV-occlusion-angiography or KODEX-EPD, was documented in 237/272 (87%) occlusion-analyses among 198 PVs (95% for left superior PV, 93% for left inferior PV, 86% for right inferior PV and 77% for right superior PV). In the final evaluation phase (group Ib) LA fluoroscopy times and dose area products were comparable to the conventional CB-ablation group (10.5±5 vs 8.8±4 minutes (p=0.23) and 403±425 vs 321±202 cGycm2 (p=0.44), whereas the amount of dye could be significantly reduced (group Ib: 31±10 ml vs group II: 70±20 ml, p&amp;lt;0.0001). Conclusion The novel KODEX-EPD PV-occlusion tool allows for accurate PV-occlusion assessment in the majority of PVs and a high acute success rate. The system has the potential to reduce dye and radiation exposure. This should be evaluated in controlled clinical trials. Funding Acknowledgement Type of funding sources: None.

Safety and Efficacy of Cryoballoon Based Pulmonary Vein Isolation in Patients with Atrial Fibrillation and a History of Cancer.

Introduction: A growing body of evidence suggests a strong association between atrial fibrillation (AF) and cancer. A relevant number of patients with a present or former malignant disease with highly symptomatic drug-refractory AF are in need of interventional therapy. Data on the safety and efficacy of catheter ablation in these patients are sparse. The present study aims to analyze the safety and efficacy of cryoballoon-based pulmonary vein isolation (CB-PVI) for symptomatic AF in patients with past or present cancer disease. Methods and Results: Consecutive patients undergoing CB-PVI for symptomatic AF at University Hospital Lübeck, Germany between July 2015 and January 2019 were included in this study. Propensity-score based matching was performed to identify comparable patients with and without cancer disease and further analyze clinical characteristics, periprocedural complications and arrhythmia-free survival. A total of 70 patients with a history of cancer undergoing CB-PVI were matched to 70 patients without a history of cancer. The frequency of complications was similar between patients with and without a history of cancer (p = 0.11), with four phrenic nerve palsies occurring in patients with a history of cancer (5.6% of the cohort) vs. one phrenic nerve palsy in patients without cancer (p = 0.36). Arrhythmia free survival after 12 months did not differ significantly in patients with and without a history of cancer (67.1 ± 5.8% vs. 77.8% ± 5.1%, p = 0.16). Conclusion: This study indicates that CB-PVI for symptomatic AF is equally safe and effective in patients with and without a history of cancer and cancer treatment.

Evaluation of predictive scores for late and very late recurrence after cryoballoon-based ablation of atrial fibrillation

PurposeStudies on predictive scores for very late recurrence (VLR) (recurrence later than 12 months) after second-generation cryoballoon-based pulmonary vein isolation (CB2-PVI) are sparse. We aimed to evaluate the frequency of late recurrence (LR) (later than 3 months) and VLR, and to validate predictive scores for LR and VLR after initial CB2-PVI.MethodsA total of 288 patients undergoing initial CB2-PVI (66 ± 11 years, 46% paroxysmal) were retrospectively enrolled in the LR cohort. In the VLR cohort, 83 patients with recurrence within 3–12 months or with < 12-month follow-up were excluded. The predictive scores of arrhythmia recurrence were assessed, including the APPLE, DR-FLASH, PLAAF, BASE-AF2, ATLAS, SCALE-CryoAF, and MB-LATER scores.ResultsDuring a mean follow-up of 15.3 ± 7.1 months, 188 of 288 (65.2%) patients remained in sinus rhythm without any recurrences. Thirty-two of 205 (15.6%) patients experienced VLR after a mean of 16.6 ± 5.6 months. Comparing the predictive values of these specific scores, the MB-LATER score showed a reliable trend toward greater risk of both LR and VLR (area under the curve in LR; 0.632, 0.637, 0.632, 0.637, 0.604, 0.725, and 0.691 (p = ns), VLR; 0.612, 0.636, 0.644, 0.586, 0.541, 0.633, and 0.680 (p = 0.038, vs. BASE-AF2, respectively)). Kaplan-Meier analysis estimated patients with higher MB-LATER scores which had favorable outcomes (24-month freedom from LR; 26.0% vs. 56.7%, p < 0.0001, VLR; 53.4% vs. 82.1%, p = 0.013).ConclusionThe MB-LATER score provided more reliable predictive value for both LR and VLR. Patients with higher MB-LATER scores may benefit from more intensive long-term follow-up.

P1025Incidence and characteristics of pulmonary vein reconduction after second-generation cryoballoon-based pulmonary vein isolation: Impact of different ablation strategies

Abstract Funding Acknowledgements none Introduction The second-generation CB (CB2, Arctic Front Advance, Medtronic Inc., Minneapolis, USA) has demonstrated high procedural success rates, relatively short procedure times, high durability of PVI and convincing long-term clinical success rates. Nevertheless, data on the impact of different ablations protocols on durability after CB2 based PVI is limited. Purpose We aimed at comparing durability of pulmonary vein isolation (PVI) following three different ablation strategies utilizing the second-generation cryoballoon (CB2) in patients with recurrence of atrial fibrillation (AF) or atrial tachycardia (AT) undergoing repeat procedures. Methods In 192 patients a total of 751 PVs were identified. All PVs (751/751, 100%) were successfully isolated during index PVI. Thirty-one out of 192 (16%) patients were treated with a bonus-freeze protocol (group 1), 67/192 (35%) patients with a no bonus-freeze protocol (group 2), and 94/192 (49%) patients with a "time-to-effect"-guided ablation protocol without bonus freezes (group 3). Results Persistent PVI was documented in 419/751 (55.8%) PVs, and in 41/192 (21%) patients all PVs were persistently isolated. The number of patients with all PVs being persistently isolated was not significant between the groups (p = 0.594). The total rate of PV reconnection was not significantly different between the three groups (p = 0.134) and the comparison of individual PVs revealed also no differences for different ablation protocols (p-values for RSPV: 0.424, RIPV: 0.541, LSPV: 0.788, LIPV: 0.346, LCPV: 0.865). The procedure times were significantly reduced in non-bonus freeze ablation protocols and/or when applying individualized application times (group 1: 123.4 ± 31.5min, group 2: 112.9 ± 39.8 min, group 3: 86.67 ± 28.4 min, p &amp;lt;0.001). Conclusions A considerably high rate of persistent PVI was demonstrated in patients after index CB2-based PVI. No differences for durable PVI were detected for different ablation protocols. Therefore, individualized ablation protocols might be a beneficial ablation strategy during CB2-based PVI.

Cryoablation for atrial fibrillation.

Cryoballoon ablation for the treatment of atrial fibrillation has established itself as an effective and efficient modality for achieving pulmonary vein isolation. Over the past 13 years more than 100,000 Cryoballoon ablation procedures have been performed with the first to fourth generation cryoballoons. Over that time there have been significant advances in our understanding regarding the optimal procedural techniques. The purpose of this "topic in review" is to focus on the practical aspects of performing a Cryoballoon ablation procedure, within the context of the contemporary literature. Specifically there is a focus on how contemporary studies can inform clinical decision making and ensure operators are able to perform a safe and effective procedure.

Acute Hemoptysis Following Cryoballoon Pulmonary Vein Isolation

This study sought to assess the incidence, procedural characteristics, contributing factors, and clinical outcome of cryoballoon-based pulmonary vein isolation (CB-PVI)-related hemoptysis in a multicenter study. Hemoptysis has been described as a rare complication of CB-PVI. However, the precise mechanism and the etiology of this complication are poorly characterized. Consecutive patients undergoing CB-PVI for paroxysmal or persistent atrial fibrillation at 4 German hospitals were included in this observational analysis. A total of 4,331 CB-PVI procedures were performed between 2006 and 2019. Fifteen patients (9 men, mean age 68.1 ± 9.8 years) developed acute hemoptysis during or within 24h after CB-PVI, resulting in a hemoptysis frequency of 0.35%. Hemoptysis occurred in 6 of 720 procedures using the first-generation CB (0.83%) and in 9 of 3,611 procedures using the second-, third-, or fourth-generation CB (0.25%) (p=0.015). Bronchoscopy was performed in 8 patients and showed bleeding exclusively due to mucosal injury or due to a coagulum at a bronchus adjacent to the ablation site. Hemoptysis resolved spontaneously without any long-term sequelae in all patients, except for a 92-year-old patient who died 13days after CB-PVI due to pneumonia. No specific endobronchial treatment was necessary. Acute hemoptysis after CB-PVI is a rare but potentially life-threatening complication that is usually self-limiting. Direct thermal injury of bronchi adjacent to a pulmonary vein seems to be the most likely mechanism.

Second-generation cryoballoon-based pulmonary vein isolation: Lessons from a five-year follow-up

BackgroundPulmonary vein isolation (PVI) using the second-generation cryoballoon (CB2) for atrial fibrillation (AF) treatment has demonstrated encouraging procedural success rates and mid-term results. However, long-term follow-up data on outcome is sparse. The current study is reporting on five-year clinical outcomes following CB2-based PVI in patients with paroxysmal AF (PAF) and persistent AF (PersAF). MethodsA total of 139 patients underwent index CB2-based PVI patients (PAF: n = 105, 76% and PersAF: n = 34, 34%) in two electrophysiology centers. Freeze-cycle duration was 240 s. After successful PVI a bonus freeze-cycle of the same duration was applied in the first 71 patients while the bonus-freeze was omitted in 68 following patients. Three patients (2.2%) were lost to follow-up. ResultsAfter a median follow-up duration of 60 months (interquartile range: 46, 72 months) 74/136 (54.4%) patients remained in stable sinus rhythm (PAF: 62/104, 59.6%; PersAF: 15/32, 46.9%). Significant differences were observed concerning 5-year clinical outcome between PAF and PersAF patients (p = 0.0315). After a mean of 1.32 ± 0.6 procedures (2nd and 3rd procedure by radiofrequency ablation) and a median follow-up duration of 60 (37, 68) months 90/136 (66.2%) patients remained in stable sinus rhythm (PAF: 72/104 (69.2%), PersAF: 21/32 (65.6%), p = 0.0276). For the comparison of bonus-freeze vs no-bonus-freeze protocols no differences were observed (53.5% vs 57.4%, p = 0.650). ConclusionsThe five-year single-procedure success rate for CB2-based PVI was 54.4% and increased to 66.2% following repeat RF-based procedures. No differences were detected comparing bonus-freeze and no-bonus-freeze protocols.

Emergency department attendance and reasons for consultation after cryoballoon ablation for pulmonary vein isolation of atrial fibrillation

Introduction and objectivesThere are few data on emergency visits after cryoballoon-based pulmonary vein isolation. The aim of this study was to quantify emergency department visits during the first 3 months after the procedure and to identify the reasons for consultation, final diagnoses, and the therapeutic approach. MethodsObservational, retrospective study of 330 consecutive patients undergoing a first cryoballoon-based ablation procedure. Patients were followed up for 90 days after the procedure. We recorded emergency visits, symptoms, electrocardiographic data, and the therapeutic approach. Final diagnoses were classified as rhythm disorder, confirmed complication, possible complication, and unrelated to the procedure or to the arrhythmic disorder. ResultsA total of 112 (34%) patients attended the emergency department, 50 (44.6%) for palpitations. Sustained atrial arrhythmias were documented in 44 (39.3%) patients. Among the 29 (25.9%) visits for complications potentially related to the procedure, 5 were confirmed inguinal puncture complications and 10 were classified as unconfirmed possible complications. Forty-one visits were unrelated to the procedure or to the arrhythmic disorder. A total of 21.4% of the visits were due to palpitations requiring no therapeutic action. ConclusionsA third of the patients attended the emergency department at least once, with the most frequent reason being arrhythmia-related symptoms. Late complications were rare and generally mild. Up to 20% of emergency visits could potentially be avoided by the availability of a teleconsulting system with remote electrocardiogram transmission.