Pulmonary Vein Isolation with the Cryoballoon Technique: Feasibility, Procedural Outcomes, and Adoption in the Real World: Data from One Shot Technologies TO Pulmonary Vein Isolation (1STOP) Project

Timing of cryoballoon pulmonary vein isolation to prevent atrial fibrillation recurrence

BACKGROUND

The aims of this analysis were: to evaluate the impact of timing of ablation on the rate of atrial arrhythmias recurrence, verify if the timing of ablation impact differently in patients with paroxysmal and persistent AF.

METHODS

Three thousand two hundred and five patients (60.5 ± 10 years, female 28.4%%, 78.8%% paroxysmal AF) were included in the analysis. All patients underwent only cryoballoon (CB) pulmonary vein (PV) isolation during the index procedure.

RESULTS

The mean procedure time was 102.8 ± 50 min, with a mean fluoroscopy time of 26.3 ± 49 min. Acute PV isolation was achieved in 11760/11793 (99.7%) PVs. A total of 91 (2.8%) patients experienced a procedure-related complication. During the observation period 913/3205 (28.5%) patients had at least one atrial arrhythmias episode: 28% of patients with paroxysmal AF vs 33% of patients with persistent AF. In multivariate analysis, persistent AF together with time from symptomatic AF diagnosis to ablation, female sex, and ablation time showed to be significant predictors for AF recurrence. In particular, months from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence (HR = 1.23, 95% CI = 1.03-1.46, p = 0.020). In patients with paroxysmal AF, the multivariate analysis confirmed that months from first symptomatic AF episode > 18 month was an independent predictor of AF recurrence together with age > 62 years and female sex. In patients with persistent AF, the time from persistent AF showed to be significant predictor for AF recurrence.

CONCLUSIONS

In this multicenter analysis, time from first symptomatic AF episode > 18 months was a significant predictor of AF recurrence after CB PV isolation.

Patient report outcomes in cryoballoon ablation of atrial fibrillation during the COVID Era: Insights from the 1STOP project

BACKGROUND

Pulmonary vein isolation by cryoablation (PVI-C) is a standard therapy for the treatment of patients with symptomatic atrial fibrillation (AF). AF symptoms are highly subjective; however, they are important outcomes for the patient. The aim is to describe the use and impact of a web-based App to collect AF-related symptoms in a population of patients who underwent PVI-C in seven Italian centers.

METHODS

A patient App to collect AF-related symptoms and general health status was proposed to all patients who underwent an index PVI-C. Patients were divided into two groups according to the utilization of the App or the non-usage.

RESULTS

Out of 865 patients, 353 (41%) subjects composed the App group, and 512 (59%) composed the No-App group. Baseline characteristics were comparable between the two cohorts except for age, sex, type of AF, and body mass index. During a mean follow-up of 7.9±13.8 months, AF recurrence was found in 57/865 (7%) subjects with an annual rate of 7.36% (95% CI:5.67-9.55%) in the No-App versus 10.99% (95% CI:9.67-12.48%) in the App group, p=0.007. In total, 14,458 diaries were sent by the 353 subjects in the App group and 77.1% reported a good health status and no symptoms. In only 518 diaries (3.6%), the patients reported a bad health status, and bad health status was an independent parameter of AF recurrence during follow-up.

CONCLUSIONS

The use of a web App to record AF-related symptoms was feasible and effective. Additionally, a bad health status reporting in the App was associated with AF recurrence during follow-up.

Safety and efficacy of cryoablation for atrial fibrillation in young patients: A multicenter experience in the 1STOP project

BACKGROUND

Atrial fibrillation (AF) is an uncommon arrhythmia in young adults without structural heart disease, and cryoballoon pulmonary vein isolation (CB-PVI) is an important therapeutic strategy for rhythm control in patients with drug-refractory AF. The aim of this analysis was to evaluate efficacy and safety of CB-PVI in a large cohort of young patients in comparison with middle-aged adults in a real-world setting.

METHODS

From 2012 to 2020, a total of 3033 patients with AF underwent CB-PVI and were followed prospectively in the framework of the 1STOP Clinical Service project, involving 34 Italian centers. Out of 3033 total 1STOP project subjects, a subgroup of 1318 patients were defined which included a YOUNG group (age ≤ 45 years; n = 368) and a MIDDLE-AGED group (age 60-65 years; n = 950).

RESULTS

The acute success rate of PVI did not differ between the two cohorts (99.9 ± 1.3% vs. 99.8 ± 3.2%, p = 0.415). There was no difference in procedural characteristics, and periprocedural complication rates were similar among the two cohort (1.9% vs. 2.3%, p = 0.646). The 12-month freedom from AF recurrence was 88.9% (95% confidence interval [CI]: 84.7-92.0) in the YOUNG cohort and 85.6% (95% CI: 82.9-88.0) in the MIDDLE-AGED group. At 36-month follow-up, freedom from AF recurrence was 72.4% (65.5%-78.2%) and 71.8% (67.7%-75.6%), respectively with no significant difference among groups (p = 0.550).

CONCLUSION

CB-PVI had similar efficacy and safety in YOUNG and MIDDLE-AGED patients. Younger age did not affect acute procedural results, complication rate, or AF recurrence after a single procedure.

Cryoballoon Ablation for Persistent and Paroxysmal Atrial Fibrillation: Procedural Differences and Results from the Spanish Registry (RECABA)

Introduction: Cryoballoon ablation (CBA) has become a standard treatment for paroxysmal atrial fibrillation (PaAF) but limited data is available for outcomes in patients with persistent atrial fibrillation (PeAF). Methods: We analyzed the first 944 patients included in the Spanish Prospective Multi-center Observation Post-market Registry to compare characteristics and outcomes of patients undergoing CBA for PeAF versus PaAF. Results: A total of 944 patients (57.8 ± 10.4 years; 70.1% male) with AF (27.9% persistent) were prospectively included from 25 centers. PeAF patients were more likely to have structural heart disease (67.7 vs. 11.4%; p < 0.001) and left atrium dilation (72.6 vs. 43.3%; p < 0.001). CBA of PeAF was less likely to be performed under general anesthesia (10.7 vs. 22.2%; p < 0.001), with an arterial line (32.2 vs. 44.6%; p < 0.001) and assisted transeptal puncture (11.9 vs. 17.9%; p = 0.025). During an application, PeAF patients had a longer time to −30 °C (35.91 ± 14.20 vs. 34.93 ± 12.87 s; p = 0.021) and a colder balloon nadir temperature during vein isolation (−35.04 ± 9.58 vs. −33.61 ± 10.32 °C; p = 0.004), but received fewer bonus freeze applications (30.7 vs. 41.1%; p < 0.001). There were no differences in acute pulmonary vein isolation and procedure-related complications. Overall, 76.7% of patients were free from AF recurrences at 15-month follow-up (78.9% in PaAF vs. 70.9% in PeAF; p = 0.09). Conclusions: Patients with PeAF have a more diseased substrate, and CBA procedures performed in such patients were more simplified, although longer/colder freeze applications were often applied. The acute efficacy/safety profile of CBA was similar between PaAF and PeAF patients, but long-term results were better in PaAF patients.

Safety and Efficacy of Cryoballoon Ablation of Atrial Fibrillation in relation to the Patients' Age: Results from a Large Real-World Multicenter Observational Project

Background

The real-world efficacy and safety of atrial fibrillation (AF) ablation in particularly young and elderly patients are still under debate. The aim of the analysis was to investigate the effect of age on the efficacy and safety of cryoballoon ablation (CBA).

Methods

2,534 patients underwent pulmonary vein isolation (PVI) by way of CBA for paroxysmal or persistent drug-resistant and symptomatic AF. The population was divided into age quartiles for evaluation, including (1) <53 years, (2) ≥53 and <61 years, (3) ≥61 and <67 years, and (4) ≥67 years. Furthermore, outcomes were analyzed in patients <41 years, ≥41 and ≤74, and >74 years old. Procedural data and complications were collected, and atrial fibrillation recurrences were evaluated during follow-up.

Results

Procedural-related complications (4.1%) were similar in the four subgroups according to age. At the 12-month follow-up, freedom from AF recurrence was 79.2%, 77.4%, 76.8%, and 75.2% (p=0.21), respectively (with increasing age). At 24-month follow-up, similar incidences of AF recurrence were observed in the four subgroups. When the sample was arbitrarily divided into the three age groups, a higher rate of recurrence was observed in older patients with regard to long-term follow-up (freedom from AF recurrence was 71.8% and 40.9%, respectively, at 12 and 24-month follow-up). In the univariate and multivariate analysis, age did not result in a significant predictor of AF recurrence during follow-up; however, a trend toward higher AF recurrences rates in patients ≥67 years was observed.

Conclusion

The data demonstrated a high degree of safety during CBA across all patient ages. Procedural performance and complications were similar between different ages; AF recurrences seem to be more frequent in patients over 74 years.

Cryoballoon Catheter Ablation in Korean Patients With Paroxysmal and Persistent Atrial Fibrillation: One Year Outcome From the Cryo Global Registry

Catheter ablation using the cryoballoon is a well-established treatment strategy for patients with atrial fibrillation (AF). To our knowledge, the current sub-analysis of the Cryo Global Registry is the first multicenter study describing the outcomes of cryoballoon ablation (CBA) in real-world Korea clinical practice. Overall, 299 patients were enrolled in 3 Korean centers. Safety, efficacy, healthcare utilization, and arrhythmia disease burden outcomes were assessed. This study demonstrated that CBA according to standard-of-care usage in Korea is safe and effective in preventing AF recurrence, repeat ablation, cardiovascular-related hospitalization, and AF-related symptoms at 12 months after the index ablation.

Background and Objectives

Cryoballoon catheter ablation for the treatment of patients with symptomatic atrial fibrillation (AF) has been adopted globally, but there are limited multicenter reports of 12-month outcomes in the Korean patient population. This analysis evaluated the clinical performance and safety of cryoballoon ablation (CBA) according to standard-of-care practices in Korea.

Methods

This evaluation of Korean patients with AF was conducted within the larger Cryo Global Registry, which is a prospective, multicenter, post-market registry. Freedom from a ≥30-second recurrence of atrial arrhythmias (after a 90-day blanking period until 12 months) and procedural safety were examined in subjects treated with CBA at 3 Korean centers.

Results

Overall, 299 patients with AF (60±11 years old, 24.7% female, 50.5% paroxysmal AF) underwent CBA using the Arctic Front Advance cryoballoon. Of those, 298 were followed-up for at least 12 months. Mean procedure-, left atrial dwell- and fluoroscopy time was 76±21 minutes, 56±23 minutes, and 27±23 minutes, respectively. Freedom from AF recurrence at 12 months was 83.9% (95% confidence interval [CI], 76.9–88.9%) in the paroxysmal and 61.6% (95% CI, 53.1–69.0%) in the persistent AF cohort. Rhythm monitoring was performed on average 4.7±1.4 times during the follow-up period. Serious device- or procedure-related adverse events occurred in 2 patients (0.7%). The 12-month Kaplan-Meier estimate of freedom from repeat ablation and cardiovascular-related hospitalization was 93.8% (95% CI, 90.4–96.1%) and 89.7% (95% CI, 85.6–92.7%), respectively.

Conclusions

CBA is an efficient, effective, and safe procedure for the treatment of AF patients when used according to real-world practices in Korea.

Trial Registration

ClinicalTrials.gov Identifier: NCT02752737

Duration of Applications Affects the Long-Term Efficacy of Cryoballoon Ablation Pulmonary Veins

Aim      To evaluate the effect of cryo-exposure duration and the use of the Achieve circular mapping catheter on efficacy of cryoballoon ablation (CBA).Material and methods  CBA of pulmonary vein ostia (PVO) is a major method for heart rhythm control in patients with atrial fibrillation (AF). Since the inception, the PVO CBA method has evolved; the recommended application time was changed, and the Achieve circular catheter appeared. We performed a retrospective analysis of PVO CBA administered to patients with AF in the I.V. Davydovsky Municipal Clinical Hospital from 2017 through 2019. The study included 100 patients with available clinical and demographic characteristics and remote results of the intervention. Three patient groups were analyzed based on differences in surgical techniques: group 1, Guidewire / 240 (n=31) with the cryoballoon placing on a guidewire and PVO exposure duration of 240 s; group 2, Guidewire / 180 (n=26) with the cryoballoon placing on a guidewire and PVO exposure duration of 180 s; and group 3, Achieve / 180 (n=43) with the cryoballoon placing on the mapping catheter Achieve and PVO exposure duration of 180 с. The follow-up period was 33.2±4.5, 15.2±6.1, and 12.2±4.1 months in the Guidewire / 240, Guidewire / 180, and Achieve / 180 groups, respectively. The intervention was considered effective when there was no relapse at the time of interview. A relapse of AF was determined as one or more paroxysms recorded on electrocardiogram (ECG) or during 24-h ECG monitoring; the "blind period" (first 3 months after the procedure) was excluded from the follow-up. Safety evaluation included clinically significant complications, such as phrenic nerve damage, hemopericardium, gastroparesis, hemoptysis, acute cerebrovascular disease, and formation of atrio-esophageal fistula. Effects of independent factors were determined with binary logistic regression.Results In the Guidewire / 240 group, efficacy of PVO CBA for the maximum follow-up period was 74.4%, which was significantly different from the value for the Guidewire / 180 group (57.7 %, р=0.015). At the same time, the difference between the Guidewire / 240 and Achieve / 180 groups was statistically non-significant for a comparable follow-up period (р=0.144). Clinically significant complications were absent in all 3 groups. The independent factors that significantly increased the PVO CBA efficacy were the cryo-exposure duration of 240 s compared to 180 s (р= 0.018) and the use of the Achieve catheter (р=0.014).Conclusion      Decreasing the cryo-exposure duration to less than 240 s is impractical (in absence of Achieve mapping catheter) since it impairs the long-term efficacy of PVO CBA and does not influence the risk of complications.

A Novel Temperature-Controlled Radiofrequency Catheter Ablation System Used to Treat Patients With Paroxysmal Atrial Fibrillation

OBJECTIVES

DIAMOND-AF (DiamondTemp™ Ablation System for the Treatment of Paroxysmal Atrial Fibrillation) was a prospective, multicenter, noninferiority, randomized trial that compared the safety and effectiveness of the DTA system versus those of a force-sensing RF ablation system (control) for the treatment of patients with drug-refractory, recurrent, symptomatic paroxysmal atrial fibrillation (AF).

BACKGROUND

Irrigated radiofrequency (RF) ablation catheters lose tissue temperature acuity, which is vital in assessing lesion formation. DiamondTemp Ablation (DTA) was designed to re-establish accurate tissue temperature measurements during ablation.

METHODS

A total of 482 patients with paroxysmal AF were randomized (239 DTA, 243 control) to undergo pulmonary vein isolation and were followed up at 23 sites. Patients were screened for disease progression, cardiac characteristics, and prior interventions. Primary endpoints were effectiveness (freedom from atrial arrhythmia recurrence) and safety (composite of procedure- and device-related serious adverse events).

RESULTS

The primary safety event rate was 3.3% in the DTA group versus 6.6% in the control group (p < 0.001 vs. 6.5% noninferiority margin). Primary effectiveness was met in 79.1% of DTA subjects and 75.7% of control subjects (p < 0.001 vs. -12.5% noninferiority margin). Secondary endpoint analysis found that off-drug effectiveness favored DTA compared with the control (142 [59.4%] vs. 120 [49.4%], respectively; p = 0.03). Total RF time and individual RF ablation duration were significantly shorter with less saline infused through the DTA catheter (p < 0.001). Both arms saw clinically meaningful improvements in quality of life at 12 months.

CONCLUSIONS

Safety and efficacy of the DTA system proved noninferior to force-sensing RF ablation in a paroxysmal AF population. Efficiencies were observed using DTA with shorter total RF times, individual RF ablation durations, and less saline infusion. (DiamondTemp™ Ablation System for the Treatment of Paroxysmal Atrial Fibrillation; NCT03334630).

Predictive role of early recurrence of atrial fibrillation after cryoballoon ablation

Aims

The aims of this study were to determine the rate and the predictors of early recurrences of atrial fibrillation (ERAF) after cryoballoon (CB) ablation and to evaluate whether ERAF correlate with the long-term outcome.

Methods and results

Three thousand, six hundred, and eighty-one consecutive patients (59.9 ± 10.5 years, female 26.5%, and 74.3% paroxysmal AF) were included in the analysis. Atrial fibrillation recurrence, lasting at least 30 s, was collected during and after the 3-month blanking period. Three-hundred and sixteen patients (8.6%) (Group A) had ERAF during the blanking period, and 3365 patients (Group B) had no ERAF. Persistent AF and number of tested anti-arrhythmic drugs ≥2 resulted as significant predictors of ERAF. After a mean follow-up of 16.8 ± 16.4 months, 923/3681 (25%) patients had at least one AF recurrence. The observed freedom from AF recurrence, at 24-month follow-up from procedure, was 25.7% and 64.8% in Groups A and B, respectively (P &lt; 0.001). ERAF, persistent AF, and number of tested anti-arrhythmic drugs ≥2 resulted as significant predictors of AF. In a propensity score matching, the logistic model showed that ERAF 1 month after ablation are the best predictor of long-term AF recurrence (P = 0.042).

Conclusion

In patients undergoing CB ablation for AF, ERAF are rare and are a strong predictor of AF recurrence in the follow-up, above all when occur &gt;30 days after the ablation.

Cryoballoon or radiofrequency ablation? Alternating technique for repeat procedures in patients with atrial fibrillation

BACKGROUND

Which technique is better for repeat ablation in patients with atrial fibrillation (AF) remains unclear. The aim of the study was to compare long-term efficacy of repeat ablation using the alternative technique for the first redo ablation procedure: (a) cryoballoon (CB) re-ablation after a failed index pulmonary vein isolation (PVI) with radiofrequency (RF) ablation, RF-then-CB group or (b) RF repeat ablation following a failed CB ablation, CB-then-RF group.

METHODS

Within the 1STOP Italian Project, consecutive patients undergoing repeat ablation with a different technique from the index procedure were included.

RESULTS

We studied 474 patients, 349 in RF-then-CB and 125 in CB-then-RF group. Less women (21% vs 30%; P = .041), more persistent AF (33% vs 22%; P = .015), longer duration of AF (60 vs 31 months; P < .001), and more hypertension (50% vs 36%; P = .007) were observed in the RF-then-CB cohort as compared with the CB-then-RF group. The number of reconnected PVs was 3.7 ± 0.7 and 1.4 + 1.3 in RF-then-CB and CB-then-RF group, respectively (P < .001). During the follow-up, significantly less AF recurrence occurred in the CB-then-RF group (22% vs 8%, HR = 0.46; 95% CI: 0.24-0.92; P = .025). Cohort designation was the only independent predictor of AF recurrence.

CONCLUSION

Alternation of energy source for repeat ablation was safe and effective, regardless the energy used first. However, patients initially treated with CB PVI undergoing repeat ablation with RF current had less AF recurrence at long-term follow-up as compared with those originally treated by RF ablation receiving a CB repeat ablation.

Risk of atrioesophageal fistula with cryoballoon ablation of atrial fibrillation

Background

Although 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.

Objective

To report the global, user-reported incidence of AEF associated with cryoballoon ablation for the treatment of atrial fibrillation using Medtronic's complaint database.

Methods

User-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.

Results

More 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.

Conclusions

AEF 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.

Achieving contrast-free ultra-low radiation exposure without compromising safety and acute efficacy through evolving AF cryoballoon ablation procedure techniques

INTRODUCTION

In general, early experience with the first-generation cryoballoon introduced an increase in radiation exposure as compared to traditional radiofrequency ablations for atrial fibrillation (AF). However, through operator vigilance and the incorporation of various techniques and technologies, procedural radiation exposure can be managed to an exceptionally low level while maintaining the safety and efficacy of the cryoballoon procedure.

METHODS AND RESULTS

A retrospective chart review of all consecutive AF ablation procedures performed by a single operator at a single high-volume center with the second-generation cryoballoon (Arctic Front Advance) was performed between 2014 and 2017. Procedural and radiation exposure data were collected and analyzed year-over-year. 307 cases were reviewed with the majority as index procedures (95%) and patients presenting in paroxysmal AF (87%). The observed median absorbed dose was 2.4 mGy (interquartile range (IQR) = 1.0,6.2) and decreased significantly from 6.7 mGy (IQR = 1.6,6.2) in 2014 to 2.0 mGy (IQR = 1.5,4.5) in 2017 (P < 0.001). Median fluoroscopy time was 0.4 min (IQR = 0.25,0.75) and demonstrated reductions from 0.75 min (IQR = 0.40,1.4) in 2014 to 0.20 min (IQR = 0.10,0.40) in 2017 (P < 0.001). No radiopaque contrast agent was used in any procedure. A complication rate of 2% (6 total events) was observed, and no cases resulted in stroke, death, permanent phrenic nerve injury, or pulmonary vein stenosis. In total, 304 of 307 (99%) procedures resulted in complete isolation of all pulmonary veins.

CONCLUSION

Ultra-low radiation doses and contrast-free procedures can be achieved as part of an overall "safety-first" approach during cryoballoon AF ablation without compromising safety or acute efficacy.

Comparison of cryoballoon ablation for atrial fibrillation guided by real-time three-dimensional transesophageal echocardiography vs. contrast agent injection

Background:

Pulmonary vein (PV) occlusion generally depends on repetitive contrast agent injection when cryoballoon ablation for atrial fibrillation (AF). The present study was to compare the effect of cryoballoon ablation for AF guided by transesophageal echocardiography (TEE) vs. contrast agent injection.

Methods:

Eighty patients with paroxysmal AF (PAF) were enrolled in the study. About 40 patients underwent cryoballoon ablation without TEE (non-TEE group) and the other 40 underwent cryoballoon ablation with TEE for PV occlusion (TEE group). In the TEE group during the procedure, PVs were displayed in 3-dimensional images to guide the balloon to achieve PV occlusion. The patients were followed up at regularly scheduled visits every 2 months.

Results:

No differences were identified between the groups in regard to the procedure time and cryoablation time for each PV. The fluoroscopy time (6.7 ± 4.2 min vs. 17.9 ± 5.9 min, P < 0.05) and the amount of contrast agent (3.0 ± 5.1 mL vs.18.1 ± 3.4 mL, P < 0.05) in the TEE group were both less than the non-TEE group. At a mean of 13.0 ± 3.3 mon follow-up, success rates were similar between the TEE group and non-TEE group (77.5% vs. 80.0%, P = 0.88).

Conclusions:

Cryoballoon ablation with TEE for occlusion of the PV is both safe and effective. Less fluoroscopy time and a lower contrast agent load can be achieved with the help of TEE for PV occlusion during procedure.

Is the time between first diagnosis of paroxysmal atrial fibrillation and cryoballoon ablation a predictor of efficacy?

AIMS

Cryoablation is an indicated therapy for the treatment of recurrent atrial fibrillation through pulmonary vein isolation; however, the optimal time between first diagnosis of atrial fibrillation and cryoablation is still unknown. We aimed to assess the clinical efficacy and safety of early versus later treatment of patients with paroxysmal atrial fibrillation by cryoablation.

METHODS

Five hundred and ten patients underwent atrial fibrillation cryoablation and were prospectively followed for at least 6 months in 43 Italian cardiology centers. The population was divided into two groups according to the time since the first diagnosis of atrial fibrillation until the index cryoablation procedure. An early-treatment group had an elapsed time of 15 months or less from atrial fibrillation diagnosis until cryoablation, and the late-treatment group had an elapsed time of greater than 15 months. During the evaluation, clinical efficacy was defined as atrial fibrillation recurrence outside a landmark 90-day blanking period, and safety was defined as the reporting of all procedure-related complications.

RESULTS

In the total cohort, cryoablation was performed after a median of 36 months from the point of the patient diagnosis with drug refractory symptomatic recurrent atrial fibrillation. The early-treatment group was composed of 130 (25%) patients, whereas the late-treatment group had 380 (75%) patients. Both cohorts had similar baseline clinical characteristics. Of 510 patients, 22 had a complication related to the procedure with no difference between the two groups. Multivariable analysis showed that the risk of atrial fibrillation recurrence was significantly higher in the late-treatment group (hazard ratio: 1.77; 95% confidence interval 1.00-3.13) CONCLUSION: In our multicenter observational examination, cryoablation was well tolerated and effective in the treatment of patients with drug refractory symptomatic paroxysmal atrial fibrillation. Reducing the time between diagnosis and ablation brought about a treatment that had a lower risk of atrial fibrillation recurrence with no change in safety.(Italian ClinicalService Project: NCT01007474).

Cryoballoon ablation of atrial fibrillation is effectively feasible without previous imaging of pulmonary vein anatomy: insights from the 1STOP project

BACKGROUND

Pulmonary vein isolation by cryoablation (PVI-C) is a standard therapy for the treatment of atrial fibrillation (AF); however, PVI-C can become a challenging procedure due to the anatomy of the left atrium and pulmonary veins (PVs). Importantly, the utility of imaging before the procedure is still unknown regarding the long-term clinical outcomes following PVI-C. The aim of the analysis is to evaluate the impact of imaging before PVI-C on procedural data and AF recurrence.

METHODS

Patients with paroxysmal AF underwent an index PVI-C. Data were collected prospectively in the framework of 1STOP ClinicalService® project. Patients were divided into two groups according to the utilization of pre-procedural imaging of PV anatomy (via CT or MRI) or the non-usage of pre-procedural imaging.

RESULTS

Out of 912 patients, 461 (50.5%) were evaluated with CT or MRI before the PVI-C and denoted as the imaging group. Accordingly, 451 (49.5%) patients had no pre-procedural imaging and were categorized as the no imaging group. Patient baseline characteristics were comparable between the two cohorts, but the ablation centers that comprised the imaging group had fewer PVI-C cases per year than the no imaging group (p < 0.001). The procedure, fluoroscopy, and left atrial dwell times were significantly shorter in the no imaging cohort (p < 0.001). The rates of complications were significantly greater in the imaging group compared to the no imaging group (6.9% vs. 2.7%; p = 0.003); this difference was attributed to differences in transient diaphragmatic paralysis. The 12-month freedom from AF was 76.2% in the imaging group and 80.0% in the no imaging group (p = 0.390).

CONCLUSIONS

In our analysis, PVI-C was effective regardless of the availability of imaging data on PV anatomy.

Percutaneous Closure of Persistent Atrial Septal Defects After Pulmonary Vein Isolation

Pulmonary vein isolation (PVI) with radiofrequency or cryoballoon ablation to treat atrial fibrillation requires trans-septal puncture. This creates a small iatrogenic atrial septal defect (iASD). In most patients, the defect spontaneously closes after 3-6 months. However, persistent iASDs can cause hemodynamic changes and adverse consequences from inter-atrial shunting. Persistent post PVI iASDs that are clinically significant can be closed percutaneously. This diagnosis should be considered in patients with worsening dyspnea or fatigue after PVI. We present a case of post PVI iASDs causing immediate or late onset hemodynamic changes and clinical symptoms, which improved after ASD closure. We provide a review of previously reported cases and literature on post PVI ASD prevalence, risk factors and outcomes after ASD closure.

Efficacy of cryoballoon ablation in patients with paroxysmal atrial fibrillation without time to pulmonary vein isolation assessment

BACKGROUND

Real-time visualization of the electrical activity of the pulmonary veins (PV) is not always possible in the setting of atrial fibrillation (AF) cryoballoon ablation. We investigated the relation between the effective documentation of time to PV isolation and the clinical outcome in a cohort of patients with paroxysmal AF who underwent cryoballoon ablation.

METHODS

One thousand forty two consecutive patients were enrolled. An inner lumen mapping catheter was typically used to visualize real-time electrical activity inside the PVs.

RESULTS

Time to PV isolation was documented in all targeted PVs in 391 patients (Group 1), in 651 patients it was not possible to record PV potentials and assess time to PV isolation in at least one PV (Group 2). In Group 1 a longer procedure duration and ablation time were observed, while a longer fluoroscopy time was observed in Group 2. After a mean follow-up of 14 ± 11 months, 209/1042 (20%) patients had an atrial arrhythmia recurrence (20.2% in Group 1, 19.9% in Group 2, p = 0.25). Complications occurred in 54/1042 (5.2%) patients without any difference among the two study groups.

CONCLUSION

In our retrospective analysis, in about two thirds of patients undergoing cryoballoon ablation it was not possible to acutely assess time to PV isolation in all PVs. However, one-year freedom from clinically symptomatic atrial tachyarrhythmia was similar to that of patients in which time to PV isolation was documented in all targeted veins.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov (NCT01007474).

Center experience does not influence long-term outcome and peri-procedural complications after cryoballoon ablation of paroxysmal atrial fibrillation: Data on 860 patients from the real-world multicenter observational project

BACKGROUND

The aim of this research was to evaluate whether the procedural data, the incidence of complications, and the long-term freedom from atrial fibrillation (AF) recurrences are influenced by center experience in a paroxysmal AF (PAF) population performing a first-time pulmonary vein isolation (PVI) by cryoballoon ablation (CBA).

METHODS

A total of 860 patients underwent PVI by CBA. Center experience groups were predefined according to the quartiles of the distribution regarding the amount of performed procedures: 3.1%, 10.6%, 22.7% and 63.6% of patients were respectively followed in each group from 1st (less experienced) to 4th (more experienced) quartile of experience.

RESULTS

In the entire population, median procedure and fluoroscopy time were 105 and 25 min, respectively. The median procedure time significantly decreased from 130 to 90 min (P < 0.001) as the center's experience increased. In 47 (5.5%) patients, a peri-procedural complication occurred. As the experience of centers increased, the acute intraprocedural PVI success rate increased (from 94.3% to 98.9%, P = 0.007), whereas there was a tendency towards a decreased incidence of peri-procedure complications (from 7.4% to 4.6%, P = 0.998). The mean 1-year freedom from AF recurrence probability was 78.3%, and the 18-month mean was 68.9% with no difference among the groups with different levels of experience.

CONCLUSION

CBA is a safe and effective treatment for patients with PAF. Peri-procedural complications and procedural times were low in all the analyzed sub-groups, showing a decreasing trend in function of center expertise. The long-term freedom from AF recurrence was not influenced by the level of experience. (clinicaltrials.gov: NCT01007474).

Clinical outcomes of AF patients treated with the first and second-generation of circular mapping and ablation catheter: insights from a real world multicenter experience

PURPOSE

Complete pulmonary vein isolation (PVI) is the best documented target for catheter ablation, and different technologies have shown comparable outcomes. The multielectrode phased-RF/duty cycled (PhRF/DC) pulmonary vein ablation catheter (PVAC) and its second generation (PVAC-GOLD) have shown promising clinical results in single and multicenter experiences. Our aim is to assess and compare the safety and efficacy in the real clinical practice among two generations of circular PhRF/DC catheters by performing PVI in patients suffering from recurrent atrial fibrillation (AF).

METHODS

Eighty-four AF patients treated with PVAC and 64 with PVAC-GOLD were prospectively followed in five Italian cardiology centers in the mainframe of the 1STOP-ClinicalService project.

RESULTS

Fluoroscopic and total procedure time were significantly different in the two groups. In particular, in the PVAC-GOLD group, the mean fluoroscopic time was 22.8 ± 12.7 min vs 31.6 ± 18.9 in the PVAC group (p = 0.002), and the mean total procedure duration was 117.6 ± 36.0 vs 147.4 ± 40.6, in the PVAC-GOLD group and the PVAC group, respectively (p = 0.001). Only two out of 148 patients reported a peri-procedural complication. Over 20.9 ± 12.0 months of follow-up, AF recurrence occurred in 58 patients. Kaplan-Meier freedom from AF recurrence did not differ between the two groups (64.1 ± 10% in the PVAC group vs 68.2 ± 9% in the PVAC-GOLD group at 1 year, p = ns).

CONCLUSIONS

In our multicenter analysis, AF ablation using two generations of circular PhRF/DC catheters is safe and effective. No difference was observed in terms of safety and efficacy of the AF ablation between the two catheters, with the mean procedural time being shorter in the PVAC-GOLD group.

Ablation of atrial fibrillation: single-shot techniques poised to dominate rhythm control strategies/the future is here

Over the recent years, the advent of single-shot techniques, such as circular catheter and cryoballoon ablation, has ushered in a new era in the catheter ablation approach and rhythm control strategies of patients with atrial fibrillation (AF). These techniques make it easier to navigate the heart and have the potential to decrease the threshold for, expand the access to, and increase patient and physician acceptance of rhythm-control therapies, that may lead to reduction of the AF disease burden and its socioeconomic impact. Due to technical issues the circular catheter technique is lagging behind, however the cryoballoon approach is progressing at a faster pace both in the field of technical advancements and clinical studies, all contributing to its rapid penetration in the electrophysiological community and rhythm management approaches toward the commonest cardiac arrhythmia. Comparative studies of the conventional point-by-point radiofrequency (RF) ablation technique and the cryoablation approach to pulmonary vein isolation (PVI), which constitutes the cornerstone of all ablation methods, seem to favor the cryoablation technique in certain aspects. The results of current studies converge in their conclusion that cryoablation employing current generation cryoballoons is a simplified and faster method compared to the conventional technique in achieving effective and durable PVI. Furthermore, investigators have recently proposed particular tips and parameters to serve as reliable predictors of successful and durable PVI that may enhance the clinical success of this single-shot ablation technique. These issues will be discussed in this overview and placed into perspective.