Impact of cryoballoon application abortion due to phrenic nerve injury on reconnection rates: a YETI subgroup analysis.

AIMS: Cryoballoon (CB)-based pulmonary vein isolation (PVI) is an effective treatment for atrial fibrillation (AF). The most frequent complication during CB-based PVI is right-sided phrenic nerve injury (PNI) which is leading to premature abortion of the freeze cycle. Here, we analysed reconnection rates after CB-based PVI and PNI in a large-scale population during repeat procedures. METHODS AND RESULTS: In the YETI registry, a total of 17 356 patients underwent CB-based PVI in 33 centres, and 731 (4.2%) patients experienced PNI. A total of 111/731 (15.2%) patients received a repeat procedure for treatment of recurrent AF. In 94/111 (84.7%) patients data on repeat procedures were available. A total of 89/94 (94.7%) index pulmonary veins (PVs) have been isolated during the initial PVI. During repeat procedures, 22 (24.7%) of initially isolated index PVs showed reconnection. The use of a double stop technique did non influence the PV reconnection rate (P = 0.464). The time to PNI was 140.5 ± 45.1 s in patients with persistent PVI and 133.5 ± 53.8 s in patients with reconnection (P = 0.559). No differences were noted between the two populations in terms of CB temperature at the time of PNI (P = 0.362). The only parameter associated with isolation durability was CB temperature after 30 s of freezing. The PV reconnection did not influence the time to AF recurrence. CONCLUSION: In patients with cryoballon application abortion due to PNI, a high rate of persistent PVI rate was found at repeat procedures. Our data may help to identify the optimal dosing protocol in CB-based PVI procedures. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03645577?term=YETI&cntry=DE&draw=2&rank=1 ClinicalTrials.gov Identifier: NCT03645577.

Advances in Cardiac Electrophysiology.

Despite the global COVID-19 pandemic, during the past 2 years, there have been numerous advances in our understanding of arrhythmia mechanisms and diagnosis and in new therapies. We increased our understanding of risk factors and mechanisms of atrial arrhythmias, the prediction of atrial arrhythmias, response to treatment, and outcomes using machine learning and artificial intelligence. There have been new technologies and techniques for atrial fibrillation ablation, including pulsed field ablation. There have been new randomized trials in atrial fibrillation ablation, giving insight about rhythm control, and long-term outcomes. There have been advances in our understanding of treatment of inherited disorders such as catecholaminergic polymorphic ventricular tachycardia. We have gained new insights into the recurrence of ventricular arrhythmias in the setting of various conditions such as myocarditis and inherited cardiomyopathic disorders. Novel computational approaches may help predict occurrence of ventricular arrhythmias and localize arrhythmias to guide ablation. There are further advances in our understanding of noninvasive radiotherapy. We have increased our understanding of the role of His bundle pacing and left bundle branch area pacing to maintain synchronous ventricular activation. There have also been significant advances in the defibrillators, cardiac resynchronization therapy, remote monitoring, and infection prevention. There have been advances in our understanding of the pathways and mechanisms involved in atrial and ventricular arrhythmogenesis.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Complications and mortality after catheter ablation of ventricular arrhythmias: risk in VT ablation (RIVA) score.

AIMS: Catheter ablation of ventricular arrhythmias (VA) has proven to be an effective therapeutic option for secondary arrhythmia prophylaxis. We sought to assess the procedural efficacy, safety and in-hospital mortality of a large patient cohort with and without structural heart disease undergoing VA ablation. METHODS: A total of 1417 patients (804 patients with structural heart disease) undergoing 1792 endo- and epicardial procedures were analyzed. Multivariable risk factor analysis for occurrence of major complications and intrahospital mortality was obtained and a score to allow preprocedural risk assessment for patients undergoing VA ablation procedures was established. RESULTS: Major complication occurred in 4.4% of all procedures and significantly more often in patients with structural heart disease than in structurally normal hearts (6.0 vs. 1.8%). The frequency of these periprocedural complications was significantly different between procedures with sole right ventricular and a combination of RV and LV access (0.5 vs. 3.1%). The most common complication was cardiac tamponade in 46 cases (3.0%). Intrahospital death was observed in 32 patients (1.8%). Logistic regression model revealed presence of ischemic heart disease, epicardial ablation, presence of oral anticoagulation or dual antiplatelet therapy as independent risk factors for the occurrence of complications or intrahospital death, while a history of previous heart surgery was an independent predictor with a decreased risk. Based on this analysis a risk score incorporating 5 standard variables was established to predict the occurrence of complications and intrahospital mortality. CONCLUSIONS: Safety of VA catheter ablation mainly relies on patient baseline characteristics and the type of access into the ventricles or epicardial space.

Ablation of atrial fibrillation using the fourth-generation cryoballoon Arctic Front Advance PRO.

The cryoballoon (CB) is a popular ablation technology used for pulmonary vein isolation. The fourth-generation CB, Arctic Front Advance PRO features a 40% shorter distal tip but retains the internal design from its second-generation predecessor. The Arctic Front Advance PRO and the second-generation CB demonstrated similar thermodynamic characteristics in a computational model. Several observational and retrospective studies established the acute safety and efficacy of the Arctic Front Advance PRO. Real-time electrical isolation was observed in 75-85% of pulmonary veins targeted with the Arctic Front Advance PRO resulting in shorter fluoroscopy and procedure times.

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

BACKGROUND: Pulmonary 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). METHODS: A 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. RESULTS: After 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). CONCLUSIONS: The 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.

Relationship between time-to-isolation and freeze duration: Computational modeling of dosing for Arctic Front Advance and Arctic Front Advance Pro cryoballoons.

BACKGROUND: Preclinical and clinical studies have utilized periprocedural parameters to optimize cryoballoon ablation dosing, including acute time-to-isolation (TTI) of the pulmonary vein, balloon rate of freezing, balloon nadir temperature, and balloon-thawing time. This study sought to predict the Arctic Front Advance (AFA) vs Arctic Front Advance Pro (AFA Pro) ablation durations required for transmural pulmonary vein isolation at varied tissue depths. METHODS: A cardiac-specific, three-dimensional computational model that incorporates structural characteristics, temperature-dependent cellular responses, and thermal-conductive properties was designed to predict the propagation of cold isotherms through tissue. The model assumed complete cryoballoon-to-pulmonary vein (PV) circumferential contact. Using known temperature thresholds of cardiac cellular electrical dormancy (at 23°C) and cellular nonviability (at -20°C), transmural time-to-isolation electrical dormancy (TTIED ) and cellular nonviability (TTINV ) were simulated. RESULTS: For cardiac thickness of 0.5, 1.25, 2.0, 3.0, 4.0, and 5.0 mm, the 23°C isotherm passed transmurally in 33, 38, 46, 62, 80, and 95 seconds during cryoablation utilizing AFA and 33, 38, 46, 63, 80, and 95 seconds with AFA Pro. Using the same cardiac thicknesses, the -20°C isotherm passed transmurally in 40, 55, 78, 161, 354, and 696 seconds during cryoablation with AFA and 40, 54, 78, 160, 352, and 722 seconds with AFA Pro. CONCLUSION: This model predicted a minimum duration of cryoballoon ablation (TTINV ) to obtain a transmural lesion when acute TTI of the PV was observed (TTIED ). Consequently, the model is a useful tool for characterizing CBA dosing, which may guide future cryoablation dosing strategies.

Case report: Cryoballoon ablation of the mitral isthmus using a novel mapping system.

Perimitral atrial flutter is commonly treated by deployment of a mitral isthmus line. However, the creation of a contiguous, transmural linear lesion across the anterior mitral isthmus using radiofrequency energy ablation is technically challenging and can be associated with major complications. Herein, we describe the successful deployment of a superolateral mitral isthmus line using the 28-mm cryoballoon in combination with a new mapping system.

Catheter Ablation of Ventricular Tachycardia in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia: A Sequential Approach.

Background It has been suggested that endocardial and epicardial ablation of ventricular tachycardia ( VT ) improves outcome in arrhythmogenic right ventricular cardiomyopathy/dysplasia. We investigated our sequential approach for VT ablation in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia in a single center. Methods and Results We included 47 patients (44±16 years) with definite (81%) or borderline (19%) arrhythmogenic right ventricular cardiomyopathy/dysplasia between 1998 and 2016. Our ablation strategy was to target the endocardial substrate. Epicardial ablation was performed in case of acute ablation failure or lack of an endocardial substrate. Single and multiple procedural 1- and 5-year outcome data for the first occurrence of the study end points (sustained VT /ventricular fibrillation, heart transplant, and death after the index procedure, and sustained VT /ventricular fibrillation for multiple procedures) are reported. Eighty-one radiofrequency ablation procedures were performed (mean 1.7 per patient, range 1-4). Forty-five (56%) ablation procedures were performed via an endocardial, 11 (13%) via an epicardial, and 25 (31%) via a combined endo- and epicardial approach. Complete acute success was achieved in 65 (80%) procedures, and partial success in 13 (16%). After a median follow-up of 50.8 (interquartile range, [18.6; 99.2]) months after the index procedure, 17 (36%) patients were free from the primary end point. After multiple procedures, freedom from sustained VT /ventricular fibrillation was 63% (95% CI , 52-75) at 1 year, and 45% (95% CI , 34-61) at 5 years, with 36% of patients receiving only endocardial radiofrequency ablation. A trend (log rank P=0.058) towards an improved outcome using a combined endo-/epicardial approach was observed after multiple procedures. Conclusion Endocardial ablation can be effective in a considerable number of arrhythmogenic right ventricular cardiomyopathy/dysplasia patients with VT , potentially obviating the need for an epicardial approach.

Time-to-effect guided pulmonary vein isolation utilizing the third-generation versus second generation cryoballoon: One year clinical success.

BACKGROUND: The second-generation cryoballoon (CB2) provides effective and durable pulmonary vein isolation (PVI) associated with encouraging and reproducible clinical outcome data. The latest- -generation cryoballoon (CB3) incorporates a 40% shorter distal tip, thus allowing for an increased rate of PVI real-time signal recording and facilitating individualized ablation strategies taking the time-to- -effect (TTE) into account. However, whether this characteristic translates into favorable clinical success has not been evaluated yet. Herein was investigated 1-year clinical success after CB3 in comparison to CB2 based-PVI. METHODS: One hundred and ten consecutive patients with paroxysmal or short-standing persistent atrial fibrillation (AF) underwent CB2 (n = 55 patients) -or CB3 (n = 55 patients) -based PVI. The freeze-cycle duration was set to TTE + 120 s if TTE could be recorded, otherwise a fixed freeze-cycle duration of 180 s was applied. RESULTS: A total of 217/218 (99%, CB3) and 217/217 (100%, CB2) pulmonary veins (PV) were successfully isolated. The real-time PVI visualization rate was 69.2% (CB3) and 54.8% (CB2; p = 0.0392). The mean freeze-cycle duration was 194 ± 77 s (CB3) and 206 ± 85 s (CB2; p = 0.132), respectively. During a median follow-up of 409 days (interquartile range [IQR] 378-421, CB3) and 432 days (IQR 394-455, CB2) 73.6% (CB3) and 73.1% of patients (CB2) remained in stable sinus rhythm after a single procedure (p = 0.806). CONCLUSIONS: A higher rate of real-time electrical PV recordings was seen using the CB3 as compared to CB2. There was no difference in 1-year clinical follow-up.

Efficacy and safety of cryoballoon ablation in the elderly: A multicenter study.

BACKGROUND: The prevalence of atrial fibrillation (AF) increases with age. Second-generation cryoballoon (CB2)-based PVI has demonstrated encouraging clinical results in the treatment of paroxysmal (PAF) and persistent atrial fibrillation (PersAF). The objective of this study was to assess data on safety, efficacy and long-term clinical success of CB2-based pulmonary vein isolation (PVI) in patients ≥75 years of age. METHODS: CB2-based PVI was performed in 104 patients ≥75 years of age (elderly group) and symptomatic AF (PersAF: n = 44, 42.3%) in three highly experienced German EP centers. The data was compared to propensity score matched patients with age <75 years (n = 104, control group; PersAF: n = 45, 43.3%, p = 0.956). RESULTS: The median age of the elderly group was 77.5 [75, 80] years while it was 63 [52, 70] years of control group patients (p = 0.0001). The median procedure time was 92.5 [75, 120] minutes (elderly group) and 100 [75, 120] (control group), p = 0.124. Major complications were registered in 7/104 (6.7%) elderly patients and 7/104 (6.7%) control group patients (p = 0.999). Clinical success in terms of freedom from AF recurrence after one-year follow-up was 80% (95% CI: 72-88) and 82% (95% CI: 75-90) and after three-year follow-up 59% (95% CI: 47-74) and 49% (95% CI: 37 64) for the elderly group and the control group, respectively (p = 0.7). CONCLUSIONS: CB2-based PVI in patients ≥75 years of age appears safe, is associated with low procedure times and shows promising clinical success rates equal to patients of the younger population.

What is the real recurrence rate after cryoballoon-based pulmonary vein isolation? Lessons from rhythm follow-up based on implanted cardiac devices with continuous atrial monitoring.

BACKGROUND: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging clinical results for the treatment of paroxysmal atrial fibrillation (AF) and persistent AF. However, rhythm follow-up after PVI is mainly based on Holter electrocardiography of limited duration. OBJECTIVE: The purpose of this study was to assess the real AF burden following CB2-based PVI in patients with implanted cardiac devices. METHODS: A total of 670 consecutive patients underwent CB2-based PVI at 3 electrophysiology centers. In 66 patients (9.9%), an implantable cardiac device with continuous monitor function was independently implanted before the procedure (device group). This patient cohort was compared to propensity score-matched patients without cardiac devices (n = 66; control group). RESULTS: A total of 254 of 258 PVs (98.4%0 in the device group were successfully isolated using only CB2. Postprocedural device interrogation found no device or lead malfunction related to the procedure. Periprocedural complications were registered in 7 of 66 patients (11%) in the device group and in 6 of 66 patients (9%) in the control group (P = .770). Phrenic nerve palsy occurred in 6 of 66 patients (9%) in the device group) and in 2 of 66 patients (3%) in the control group) (P = .274). Clinical success in terms of freedom from AF recurrence after a 1-year follow-up period was 63.8% (95% confidence interval 53-77) in the device group and 77.3% (95% confidence interval 68-88) in the control group (P = .038). In the device group, AF/AT burden decreased from 41.8% ± 35.0% before the procedure to 10.2% ± 22.4% after 1 year (P <.0001). CONCLUSION: CB2-PVI seems safe and feasible in patients with an implanted cardiac device. A significantly higher AF/AT burden was seen in patients with an implanted cardiac device compared to a control group.

Five-year clinical outcomes of visually guided laser balloon pulmonary vein isolation for the treatment of paroxysmal atrial fibrillation.

BACKGROUND: Visually guided laser balloon (VGLB) ablation allows for pulmonary vein isolation (PVI) under direct endoscopic control. Short- and midterm clinical outcomes are in accordance with results of radiofrequency current (RFC) ablation for the treatment of paroxysmal atrial fibrillation (PAF). OBJECTIVE: The current study sought to assess the long-term clinical outcomes of VGLB-based PVI for PAF. METHODS: A total of 90 patients [60 ± 10 years; 33 (37%) female, left atrial diameter 42 ± 4 mm] with drug-refractory PAF underwent VGLB ablation. The median duration of PAF until VGLB ablation was 36 (interquartile range 12; 84) months. Follow-up was based on outpatient clinic visits including Holter ECGs and telephone interviews. Repeat ablation due to arrhythmia recurrences was performed using RFC ablation. RESULTS: After a single VGLB procedure, 5-year freedom from arrhythmia recurrence was 51% [95% confidence interval (CI) 39-62%]. Thirty-three patients underwent repeat RFC ablation procedures, resulting in multiple procedure freedom from arrhythmia recurrence of 78% (95% CI 68-88%). Major periprocedural complications occurred in four patients (4%). CONCLUSIONS: VGLB ablation for the treatment of drug-refractory PAF is safe and results in 5-year single and multiple procedure arrhythmia-free survival of 51 and 78%, respectively.

Insights into ablation of persistent atrial fibrillation: Lessons from 6-year clinical outcomes.

INTRODUCTION: Ablation of persistent atrial fibrillation (AF) is a potential treatment option for symptomatic patients. We sought to evaluate the critical role of circumferential pulmonary vein isolation (CPVI) in the ablation of persistent AF. METHODS AND RESULTS: A total of 341 ablation procedures were performed in 174 consecutive patients with persistent AF. CPVI was performed in all patients, additional ablation was only performed if electrical cardioversion failed after CPVI. During a median follow-up (FU) of 89 (63; 89) months, stable sinus rhythm was documented in 42/170 (25%) patients after a single procedure and in 111/164 (68%) patients after 1.9 ± 1.1 procedures. Stable SR was achieved in 40/75 (53%) patients in whom only CPVI was performed during the index and repeat procedures and in 71/89 (79%) patients with CPVI plus additional ablation. The main predictor for ablation success was duration of persistent AF before the index procedure (P < 0.001, HR ± CI: 1.608 [1.034, 1.103]). Responders to CPVI during the initial procedure had a significantly better multiple-procedure outcome after 42 months of FU compared to CPVI nonresponders (P  =  0.0365). Conversion during the index procedure had no impact on clinical outcomes (P  =  0.0903). Persistent AF regressed to paroxysmal AF in 16% of patients. CONCLUSIONS: We demonstrate a 25% single- and 68% multiple-procedure success in patients with persistent AF, while stable SR was achieved in 53% of patients with pure CPVI during all procedures and in 79% of patients with CPVI plus additional ablation. Only duration of persistent AF before ablation had a statistically significant impact on ablation outcome.

Significant reduction in procedure duration in remote magnetic-guided catheter ablation of atrial fibrillation using the third-generation magnetic navigation system.

PURPOSE: The magnetic navigation system (MNS) has shown to be safe and effective for catheter ablation of atrial fibrillation (AF). However, longer procedure duration as compared to manual catheter ablation may limit its widespread use. This study aimed to assess the impact of the newest generation MNS using an optimized mapping and ablation protocol on the efficacy and safety of remote magnetic catheter (RMC)-guided pulmonary vein isolation (PVI). METHODS: This observational study included 52 patients with symptomatic AF who underwent RMC-guided PVI using the second-generation MNS Niobe II (initial 28 patients, group I) or the third-generation MNS Niobe ES in combination with an optimized mapping and ablation protocol (24 patients, group II). RESULTS: Acute PVI was achieved in 26/28 (93%) patients in group I and 24/24 patients (100%) in group II. Mean procedure time was 263.9 ± 81.9 min in group I and significantly lower in group II (139.7 ± 22.6 min, p < 0.01). Mean fluoroscopy time was 18.8 ± 8.7 min in group I and decreased to 7.9 ± 2.6 in group II (p < 0.01). After a median follow-up of 640.5 days (Q1 460.75; Q3 766.5), 16/24 (67%) patients undergoing RMC-guided PVI in group II remained in stable SR. No periprocedural complications were noted for either group. CONCLUSIONS: Use of the third-generation MNS for RMC-guided PVI is safe, effective, and drastically reduced procedure times.

Acute efficacy, safety, and long-term clinical outcomes using the second-generation cryoballoon for pulmonary vein isolation in patients with a left common pulmonary vein: A multicenter study.

BACKGROUND: Second-generation cryoballoon (CB2)-based pulmonary vein isolation (PVI) has demonstrated encouraging clinical results in the treatment of paroxysmal (PAF) and persistent atrial fibrillation (PersAF). However, the CB2 features a maximal diameter of 28 mm, and its adaptability to anatomic variations of the pulmonary veins (PVs) might be challenging. OBJECTIVE: The purpose of this study was to assess the acute efficacy, safety, and long-term clinical results of CB2-based PVI in patients with a left common pulmonary vein (LCPV). METHODS: Six hundred seventy consecutive patients underwent CB2-based PVI in 3 electrophysiology centers. In 74 patients (11%), an LCPV was identified (LCPV group). The data were compared to those from matched patients (n = 74) with normal PV anatomy and comparable baseline characteristics (control group). An antral occlusion of the complete LCPV ostium was feasible in 50% of patients in the LCPV group. If an antral occlusion could not be obtained, a sequential isolation of the first superior and inferior branches was applied. RESULTS: All 74 LCPVs were successfully isolated. A total of 64% patients (LCPV group) and 66% patients (control group) remained in sinus rhythm after mean follow-up of 1.9 ± 0.9 years (P = .820). In 18 of 26 patients (69%) with atrial tachyarrhythmia recurrence, a repeat procedure using radiofrequency energy was performed, and a total of 56% LCPVs were found to be persistently isolated (control group: 61% of left-sided PVs, P = .801). CONCLUSION: Patients with an LCPV undergoing CB2-based PVI demonstrate a high acute success rate. Comparable results with regard to clinical success and durability of PVI were shown when comparing patients of the LCPV group and the control group.

Three-Year Clinical Outcome After 2nd-Generation Cryoballoon-Based Pulmonary Vein Isolation for the Treatment of Paroxysmal and Persistent Atrial Fibrillation　- A 2-Center Experience.

BACKGROUND: Pulmonary vein isolation (PVI) using the 2nd-generation cryoballoon (CB2) for the treatment of atrial fibrillation (AF) has demonstrated encouraging acute and mid-term results. However, follow-up data on outcomes beyond 1 year are sparse. We investigated the 3-year outcome after PVI using the CB2.Methods and Results:100 patients with paroxysmal (PAF, 70/100 [70%] patients) or persistent AF (pAF, 30/100 [30%] patients) underwent CB2-based PVI in 2 experienced centers in Germany. Freeze-cycle duration was 240 s. After successful PVI a bonus freeze-cycle of the same duration was applied in the first 71 patients but was omitted in the following 29 patients. Phrenic nerve palsy occurred in 3 patients (3%); 2 patients were lost to follow-up. After a median follow-up of 38 (29-50) months, 59/98 (60.2%) patients remained in stable sinus rhythm (PAF: 48/70 (69%), pAF: 11/28 (39%) P=0.0084). In 32/39 (77%) patients with arrhythmia recurrence, a second ablation procedure using radiofrequency energy was conducted. Persistent PVI was noted in 76/125 (61%) PVs. After a mean of 1.37±0.6 procedures and a median follow-up of 35 (25-39) months, 77/98 (78.6%) patients remained in stable sinus rhythm (PAF: 56/70 (80%), pAF: 20/28 (71%), P=0.0276). CONCLUSIONS: CB2-based PVI resulted in a 60.2% single-procedure and a 78.6% multiple-procedure success rate after 3 years. Repeat procedures demonstrated a high rate of durable PVI.