Low rate of asymptomatic cerebral embolism and improved procedural efficiency with the novel pulmonary vein ablation catheter GOLD: results of the PRECISION GOLD trial

Randomized Study Comparing Radiofrequency Ablation with the PVAC Gold System vs. Antiarrhythmic Drugs in Elderly Patients with Symptomatic Atrial Fibrillation

BACKGROUND

There are no randomized studies comparing the maintenance of sinus rhythm after catheter ablation (CA) concerning treatment with antiarrhythmic drugs (AA) in elderly patients with paroxysmal atrial fibrillation (AF).

OBJECTIVES

To compare the clinical results of pulmonary vein (PV) isolation with the second-generation PVAC Gold catheter against AA treatment in elderly people with recurrent symptomatic paroxysmal AF, refractory to at least one AA, and without structural heart disease.

METHODS

Sixty patients with paroxysmal AF ≥ 65 years old were randomized to two forms of treatment: group 1: CA and group 2: AA drugs. The primary outcome was the AF recurrence-free rate after at least one year of follow-up. Secondary outcomes were: progression to persistent forms of AF, impact on quality of life (QOLF), and complications. The significance level adopted in the statistical analysis was 5% (p<0.05).

RESULTS

The AF recurrence-free rate was 80% (10% with amiodarone) in the CA group, after 1.3 procedures per patient and 65% in the AA group (60% with amiodarone), (p = 0.119) in an average follow-up of 719 days (Q1: 566; Q3: 730). The persistent AF free rate was 83.4% in the AC group and 67.7% in the AA group (p = 0.073) Both strategies showed an improvement in the AFQoL score during follow-up (p < 0.001), with no difference between the groups. Although without clinical repercussions or impact on the intellectual assessment test, 25% of patients in the CA group showed signs of cerebral embolization on brain MRI.

CONCLUSIONS

Both strategies for maintaining sinus rhythm promoted an improvement in the quality of life of elderly patients with symptomatic AF, with no statistical difference in the clinical outcomes. Additional studies using technologies with a better safety profile are needed to evaluate the benefits of CA in elderly patients with AF.

Pre- and post-procedural cardiac imaging (computed tomography and magnetic resonance imaging) in electrophysiology: a clinical consensus statement of the European Heart Rhythm Association and European Association of Cardiovascular Imaging of the European Society of Cardiology

Imaging using cardiac computed tomography (CT) or magnetic resonance (MR) imaging has become an important option for anatomic and substrate delineation in complex atrial fibrillation (AF) and ventricular tachycardia (VT) ablation procedures. Computed tomography more common than MR has been used to detect procedure-associated complications such as oesophageal, cerebral, and vascular injury. This clinical consensus statement summarizes the current knowledge of CT and MR to facilitate electrophysiological procedures, the current value of real-time integration of imaging-derived anatomy, and substrate information during the procedure and the current role of CT and MR in diagnosing relevant procedure-related complications. Practical advice on potential advantages of one imaging modality over the other is discussed for patients with implanted cardiac rhythm devices as well as for planning, intraprocedural integration, and post-interventional management in AF and VT ablation patients. Establishing a team of electrophysiologists and cardiac imaging specialists working on specific details of imaging for complex ablation procedures is key. Cardiac magnetic resonance (CMR) can safely be performed in most patients with implanted active cardiac devices. Standard procedures for pre- and post-scanning management of the device and potential CMR-associated device malfunctions need to be in place. In VT patients, imaging-specifically MR-may help to determine scar location and mural distribution in patients with ischaemic and non-ischaemic cardiomyopathy beyond evaluating the underlying structural heart disease. Future directions in imaging may include the ability to register multiple imaging modalities and novel high-resolution modalities, but also refinements of imaging-guided ablation strategies are expected.

Atrial fibrillation catheter ablation associated silent cerebral emboli: A narrative review

The incidence of silent cerebral emboli (SCE) associated with atrial fibrillation catheter ablation (AFCA) is much higher than that of stroke/transient ischemic attack (TIA). Interventional electrophysiologists have been increasingly alerted to asymptomatic cerebral infarction over the years. Plentiful studies revealed that diagnostic definitions, detection modalities, energy sources, ablation strategies, perioperative anticoagulation regimens, and patient-related factors were associated with the risk of AFCA-associated SCE. Studies related to non-interventional procedures found that SCE may prompt stroke, cognitive decline, and dementia later in life, suggesting a possible role of AFCA-associated SCE in the cognitive function of patients with AF. However, there is no consistent evidence for this view to date. Given that the majority of patients with AF being elderly and the increased risk of cognitive impairment in AF itself, efforts should be made to minimize the occurrence of AFCA-associated SCE.

Pulsed Field Ablation for the Treatment of Atrial Fibrillation: PULSED AF Pivotal Trial

BACKGROUND

Pulsed field ablation uses electrical pulses to cause nonthermal irreversible electroporation and induce cardiac cell death. Pulsed field ablation may have effectiveness comparable to traditional catheter ablation while preventing thermally mediated complications.

METHODS

The PULSED AF pivotal study (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF) was a prospective, global, multicenter, nonrandomized, paired single-arm study in which patients with paroxysmal (n=150) or persistent (n=150) symptomatic atrial fibrillation (AF) refractory to class I or III antiarrhythmic drugs were treated with pulsed field ablation. All patients were monitored for 1 year using weekly and symptomatic transtelephonic monitoring; 3-, 6-, and 12-month ECGs; and 6- and 12-month 24-hour Holter monitoring. The primary effectiveness end point was freedom from a composite of acute procedural failure, arrhythmia recurrence, or antiarrhythmic escalation through 12 months, excluding a 3-month blanking period to allow recovery from the procedure. The primary safety end point was freedom from a composite of serious procedure- and device-related adverse events. Kaplan-Meier methods were used to evaluate the primary end points.

RESULTS

Pulsed field ablation was shown to be effective at 1 year in 66.2% (95% CI, 57.9 to 73.2) of patients with paroxysmal AF and 55.1% (95% CI, 46.7 to 62.7) of patients with persistent AF. The primary safety end point occurred in 1 patient (0.7%; 95% CI, 0.1 to 4.6) in both the paroxysmal and persistent AF cohorts.

CONCLUSIONS

PULSED AF demonstrated a low rate of primary safety adverse events (0.7%) and provided effectiveness consistent with established ablation technologies using a novel irreversible electroporation energy to treat patients with AF.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04198701.

2-year outcomes of phased radiofrequency ablation for atrial fibrillation with the second-generation PVAC Gold ablation catheter

PURPOSE

The second-generation multi-electrode catheter, PVAC Gold, was designed to improve the safe delivery of phased radiofrequency energy using a "single shot" approach for pulmonary vein isolation (PVI), while retaining efficacy. This large registry presents long-term performance in a daily practice setting.

METHODS

A total of 1011 patients undergoing first time ablation for atrial fibrillation (AF) using PVAC Gold were included, 639 patients with PVI for paroxysmal AF (PAF PVI) and 372 patients with persistent or long-standing persistent AF, divided into 175 patients receiving PVI only (PersAF PVI) and 197 patients receiving PVI with additional substrate ablation (PersAF PVI +).

RESULTS

At 24-month follow-up, single procedure freedom from atrial tachyarrhythmia (ATA) was 58% (368/639) in the PAF PVI group, 44% (77/175) in the PersAF PVI group, and 29% (57/197) in the PersAF PVI + group. Allowing one repeat procedure in 33% of patients, 76%, 65%, and 54% were free from ATA at 24 months, respectively. Pulmonary vein reconnection was observed in 98% of patients with recurrent arrhythmia after PVI.

CONCLUSIONS

Although phased RF ablation with PVAC Gold is quick and safe, the efficacy outcomes are modest compared to current mainstream ablation strategies.

The AF-FICIENT magnetic resonance imaging and endoscopy safety substudy: A visually guided radiofrequency balloon ablation catheter for pulmonary vein isolation

Background

Early experience with a novel multielectrode saline-irrigated radiofrequency balloon (RFB) catheter with an integrated camera system found that it was safe and effective in performing single-shot pulmonary vein isolation (PVI) for atrial fibrillation.

Objective

The purpose of this study was to further assess potential treatment risks by looking for subclinical events.

Methods

The study was performed at 2 sites. Patients underwent PVI by RFB. A control group underwent conventional point-by-point radiofrequency ablation. Stroke scale questionnaire and brain magnetic resonance imaging (MRI) were performed before and after the ablation procedure, and esophageal endoscopy was performed after the procedure in RFB patients only.

Results

We enrolled 27 patients in the RFB group and 15 patients in the control group. The RFB and control groups were well matched [predominantly male: 62% vs 53%; CHA₂DS₂-VASc score: 1.9 ± 1.3 vs 1.5 ± 1.6; mean age 60 years in both groups]. All patients underwent successful ablation and completed study assessments. Clinically silent, new MRI diffusion weighted imaging cerebral lesions were observed in 8 patients (30%) in the RFB group and 1 patient (7%) in the control group, and 11 susceptibility weighted imaging lesions in the RFB group and 1 in the control group. Endoscopy showed a minor thermal injury in 1 patient in the RFB group.

Conclusion

An increased rate of clinically silent cerebral events was seen in the RFB group. A low rate of esophageal thermal injury was observed.

Efficacy and safety of the GOLD FORCE multicentre randomized clinical trial: multielectrode phased radiofrequency vs. irrigated radiofrequency single-tip catheter with contact force ablation for treatment of symptomatic paroxysmal atrial fibrillation

AIMS

Pulmonary vein isolation (PVI) for atrial fibrillation (AF) has become increasingly safe and effective with the evolution of single-tip ablation catheters aided by contact force sensing (ST-CF) and single-shot devices such as the second-generation pulmonary vein ablation catheter (PVAC) Gold multi-electrode array. The multicentre randomized GOLD FORCE trial was conducted to evaluate non-inferiority of safety and efficacy of PVAC Gold PVI compared to ST-CF ablation for paroxysmal AF.

METHODS AND RESULTS

The primary efficacy endpoint documented AF recurrence ≥30 s was assessed by time-to-first-event analysis after a 90-day blanking period using repeated 7-day Holters. Secondary endpoints include acute success and procedural characteristics. Safety endpoints included procedural complications, stroke/transient ischaemic attack (TIA), tamponade, bleeding, and access site complications. Two hundred and eight patients underwent randomization and PVI (103 assigned to PVAC Gold, 105 to ST-CF). Acute success rates were 95% and 97% for PVAC Gold and ST-CF, respectively. At 12 months, AF recurrence was observed in 46.6% of the PVAC Gold group and in 26.2% of the ST-CF group [absolute efficacy difference 20.4% (95% confidence interval, CI 7.5-33.2%), hazard ratio 2.05 (95% CI 1.28-3.29), P = 0.003]. PVAC Gold had significantly shorter procedure and ablation times. Complication rates were 5.7% and 4.9% for PVAC Gold and ST-CF, respectively (P = 0.782).

CONCLUSION

In this multicentre randomized clinical trial, ablation with ST-CF and PVAC Gold ablation catheters non-inferiority for efficacy was not met. AF recurrence was significantly more frequent in the PVAC Gold group compared to single-tip contact force group. Both groups had similarly low rates of adverse events. PVAC Gold ablation had significantly shorter procedure and ablation times.

Paroxysmal and persistent atrial fibrillation ablation outcomes with the pulmonary vein ablation catheter GOLD duty-cycled phased radiofrequency ablation catheter: quality of life and 12-month efficacy results from the GOLD Atrial Fibrillation Registry

Aims

The GOLD AF Registry has been designed to prospectively assess the population, indications, and outcomes using second-generation phased radiofrequency (RF) ablation (pulmonary vein ablation catheter GOLD) in a global examination of standard-of-care use for the treatment of paroxysmal and persistent atrial fibrillation (AF).

Methods and results

GOLD AF (NCT02433613) is a prospective, observational, multi-centre registry designed to characterize efficacy and safety of phased RF ablation in patients with AF. The primary endpoint was freedom from AF recurrence at 12-month follow-up after a 90-day blanking period. Ancillary objectives include safety, procedural efficiency, and quality of life (QoL). The QoL assessment using the Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) and the European Heart Rhythm Association (EHRA) Score of AF-related symptoms was collected at baseline and 12 months. In total, 1054 patients were included in this analysis (age 60.6, 67.6% male, 26.5% PersAF). Kaplan–Meier estimate of freedom from AF recurrence was 77.7% at 12 months. Peri-procedural device or procedure-related complications were observed in 26 (2.5%) patients, with a low stroke rate of 0.3%. One-year post-ablation, the EHRA AF Symptom score decreased in 68% of patients. The AFEQT score improvement was observed in 88.4% and 90.4% of patients who completed the questionnaire in-person or interviewed by phone at 12 month follow-up, respectively.

Conclusion

Phased RF ablation for the treatment of paroxysmal and persistent AF demonstrated a 77.7% freedom from AF recurrence at 12 months in addition to a significant reduction in arrhythmia symptoms and clinically meaningful improved QoL. Low peri-procedural complication rate of <3% was reported.

Acute success and safety of the second-generation PVAC GOLD phased RF ablation catheter for atrial fibrillation

PURPOSE

The second-generation multi-electrode catheter, pulmonary vein ablation catheter (PVAC) GOLD, was designed to improve the delivery of phased radiofrequency energy and reduce procedure times using a 'single-shot' approach for pulmonary vein isolation (PVI), while retaining efficacy and safety. This large registry presents acute success rates and safety outcomes in a daily practice setting.

METHODS

A total of 1017 patients undergoing first-time ablation for atrial fibrillation (AF) using PVAC GOLD were included, 644 patients with paroxysmal AF and 373 patients with non-paroxysmal AF, divided into 175 patients receiving PVI only and 198 patients receiving PVI with additional substrate modification.

RESULTS

High and comparable percentages of successful PVI could be achieved in all groups (98%, 95% and 99%; p = 0.108). The median total procedure time for all groups was 90 min [70-100]. As expected, the total procedure, ablation and fluoroscopy time were significantly longer in the PVI + substrate modification group compared with the PVI-only cases (all p < 0.001), but not between the PVI-only groups (p = 0.306, p = 0.088, p = 0.233, respectively). A total of 44 complications were observed in 43 patients (4.2%). Major complications were seen in 19 patients (1.87%) and non-major procedure-related complications were seen in 25 patients (2.46%). Complications leaving permanent sequelae were rare and occurred in only four patients (0.39%). Complications did not differ between groups (p = 0.199, p = 0.438, p = 0.240 and p = 0.465 respectively).

CONCLUSION

PVAC GOLD performs successful PVI, while reducing procedure times and retaining safety for paroxysmal, persistent and long-standing persistent AF. Safety was unaffected by additional substrate modification.

Correlation of pulmonary vein reconnection patterns after cryoballoon and duty-cycled ablation of atrial fibrillation with the time of arrhythmia recurrence

BACKGROUND

Pulmonary vein isolation (PVI) is safe and effective in the treatment of atrial fibrillation (AF). We compare and correlate pulmonary vein (PV) reconnection patterns at repeat ablation in patients with recurrent AF after PVI using duty-cycled radiofrequency (RF) technology (PVAC) or second-generation cryoballoon (CB) with the time of AF recurrence.

METHODS AND RESULTS

In total, 85 PVAC and 66 CB patients undergoing a second ablation were enrolled 9.7 ± 3.4 months after initial PVI. PV reconnections were comparably high between both groups (93% PVAC and 92% CB patients). A mean of 2.79 ± 1.2 PVs/patient were reconnected after PVAC PVI compared with 1.97 ± 0.8 in CB patients, P < .0001. 33% PVAC patients, but no CB patient had 4 reconnected PVs (P < .0001). Early AF recurrences were more frequently observed in PVAC patients with ≥2 reconnected PVs, in CB patients with ≥3 reconnected PVs (both P < .01) and patients without PV reconnection, irrespective of the ablation technique. One reconnected PV was associated with late AF recurrence only in CB patients. The correlation between number of reconnected PVs and time of AF recurrence was -0.32 for PVAC and -0.52 for CB.

CONCLUSIONS

CB PVI was associated with greater durability and lesser PV reconnections/patient. There were negative correlations for both devices between extent of PV reconnections and time of AF recurrence. CB patients with early AF recurrences- although less frequently observed compared with PVAC patients had more reconnected PVs than PVAC patients, suggesting additional effects for AF prevention after CB PVI.

Uninterrupted use of direct oral anticoagulants versus vitamin K antagonists for catheter ablation of atrial fibrillation with PVAC gold: incidence of silent cerebral microembolic events

BACKGROUND

Silent cerebral microembolic events (SCE) after duty-cycled ablation of atrial fibrillation using PVAC have been detected by cerebral magnet resonance imaging (MRI) in a substantial number of patients. The purpose of this study was to investigate if uninterrupted oral anticoagulation with non-vitamin K antagonists (NOACs) compared with vitamin K antagonists (VKA) affects the incidence of SCE after pulmonary vein isolation (PVI) using PVAC Gold.

METHODS

Eighty-four consecutive patients (62 ± 15 years, 58% male) undergoing a first PVI were prospectively enrolled. Of these, 42 were on VKA and 42 on uninterrupted NOAC treatment. An activated clotting time (ACT) ≥ 350 s was targeted for ablation.

RESULTS

Cerebral MRI the day after PVI revealed acute diffusion-weighted positive lesions in 11/42 (26%) VKA compared with 14/42 (33%) in NOAC patients (p = 0.634). No differences were found for lesion size, number of lesions/patient, and number of lesions indicating cerebral infarction (2.4% for VKA and 4.8% for NOAC patients). Seventy-five percent of NOAC patients with sporadic ACT levels < 300 s during PVI developed SCE compared with 22% of corresponding VKA patients (p = 0.030). VKA and NOAC subgroups with ACT ≥ 350 s had no reduced incidence of SCE compared with ACT 300-350 s.

CONCLUSIONS

A significant, but comparable, number of patients under uninterrupted anticoagulation with VKA or NOACs still experience SCE after PVAC Gold PVI. NOAC patients with sporadic subtherapeutic ACT levels during PVI are at the highest risk for SCE while permanent ACT levels ≥ 350 s did not further reduce the incidence of SCE in both groups.

Systematic review and network meta-analysis of atrial fibrillation percutaneous catheter ablation technologies using randomized controlled trials

AIMS

We sought out to make comparisons between all atrial fibrillation (AF) catheter ablation technologies using randomized controlled trial data. Our comparisons were freedom from AF, procedural duration, and fluoroscopy duration.

METHODS

Searches were made of EMBASE, MEDLINE, and CENTRAL databases, and studies were selected which had cryoballoon, conventional radiofrequency (RF), multipolar RF catheters, and laser technology as an arm in the study and were identified as randomized controlled trials (RCTs). These studies were analyzed for direct comparisons using conventional meta-analysis and a combination of indirect and direct comparisons via a network meta-analysis (NMA).

RESULTS

With respect to freedom from AF both direct comparisons and NMA did not demonstrate any significant difference. However in analysis of procedural and fluoroscopy duration (minutes) for the pulmonary vein ablation catheter (PVAC), both conventional analysis and NMA revealed significantly shorter procedure times, RF vs PVAC (conventional: 61.99 [38.03-85.94], P <.00001; NMA: 54.76 [36.64-72.88], P < .0001) and fluoroscopy times, RF vs PVAC (conventional: 12.96 [6.40-19.53], P = .0001; NMA: 8.89 [3.27-14.51], P < .01). The procedural duration was also shorter for the cryoballoon with NMA, RF vs CRYO (20.56 [3.47-37.65], P = .02).

DISCUSSION

Our analysis demonstrated that while there was no difference in the efficacy of the individual catheter technologies, there are significant differences in the procedural duration for the PVAC and the cryoballoon. While they may seem an attractive solution for high-volume centers, further RCTs of next-generation technologies should be examined.

Comparison of pulmonary vein reconnection patterns after multielectrode phased radiofrequency- and cryoballoon ablation of atrial fibrillation

Background

Pulmonary vein isolation (PVI) using phased radiofrequency (RF) energy has been shown to be effective in the treatment of atrial fibrillation (AF).

Methods

We characterize and compare pulmonary vein (PV) reconnection at repeat ablation in patients with AF after initially successful PVI using phased RF technology (PVAC) or 2nd generation cryoballoon (CB). Eighty five patients undergoing redo PVI using multielectrode PVAC phased RF catheter and 66 patients after CB PVI were enrolled 9.7 ± 3.4 months after the initial ablation procedure.

Results

The percentage of patients with PV reconnection(s) was comparably high between both groups (93% PVAC and 92% CB). However, 75% of all PVs and left common trunks (CTs) isolated with PVAC were reconnected, compared with 52% reconnections after CB PVI (p < 0.001). A mean of 2.79 ± 1.2 PVs and CTs/patient were reconnected after PVAC PVI compared with 1.97 ± 0.8 in CB patients, p < 0.0001. No patients in the CB group had 4 reconnected PVs, while this pattern of reconnection was observed in 33% in the PVAC group (p < 0.0001). The percentage of patients in the PVAC group with ≥3 reconnected PVs was significantly higher compared with CB patients (56 patients (66%) vs. 17 patients (26%), p < 0.0001), while the percentage of patients with no PV reconnection was comparably low in PVAC and CB patients (7 and 8%, respectively). CTs were most frequently reconnected after PVAC PVI (94%) and left superior PVs after CB ablation (67%), respectively.

Conclusions

The number of patients with recurrent AF and PV reconnection(s) at redo PVI was comparably high between both groups. However, the extent and distribution of PV reconnections was different in many aspects, indicating more stable atrial lesions after CB PVI compared with PVAC technology.

Evaluation of stroke incidence with duty-cycled multielectrode-phased radiofrequency ablation of persistent atrial fibrillation results of the VICTORY AF Study

INTRODUCTION

The VICTORY AF Study was designed to evaluate the risk of the procedure and/or device-related strokes in patients with PersAF on warfarin undergoing ablation with a phased radiofrequency (RF) system.

METHODS

The VICTORY AF trial was a prospective, multicenter, single-arm, investigational study. PersAF patients on vitamin K antagonism without major structural heart disease or history of stroke/transient ischemic attack undergoing phased RF ablation for atrial fibrillation (AF) were included. The primary outcome was the incidence of the procedure and/or device-related stroke within 30 days of the ablation by a board-certified neurologist's assessment. The secondary outcomes were an acute procedural success, 6 months effectiveness (defined as the reduction in AF/atrial flutter episodes lasting ≥10 minutes by 48-hour Holter 6 months postablation) and the number of patients with pulmonary vein (PV) stenosis.

RESULTS

A total of 129 (108 PersAF, 21 long-standing PersAF) patients were treated (mean age: 60.6 ± 7.7; 79.8% male, 54.3% CHA2Ds2-VASc score ≥ 2). Two nondisabling strokes were reported (1.6%); one before discharge and the second diagnosed at the 30-day visit. Due to slow enrollment, the study was terminated before reaching the 95% one-sided upper confidence boundary for stroke incidence. Acute procedural success was 93.8%, and at 6 months, 72.8% of patients demonstrated ≥90% reduction in AF burden, 78.9% were off all antiarrhythmic drugs. There were no patients with PV stenosis of greater than 70%.

CONCLUSIONS

VICTORY AF demonstrated a 1.6% incidence of stroke in PersAF undergoing ablation with a phased RF system which did not meet statistical confidence due to poor enrollment. The secondary outcomes suggest comparable efficacy to phased RF in the tailored treatment of permanent AF trial. Rigorous clinical evaluation of the stroke risk of new AF ablation technologies as well as restriction to Vitamin K antagonist anticoagulation appears to be unachievable goals in a clinical multicenter IDE trial of AF ablation in the current era.

Intracardiac Fibrinolysis and Endothelium Activation Related to Atrial Fibrillation Ablation with Different Techniques

Objective

The effect of pulmonary vein isolation (PVI) on fibrinolytic and endothelial activation with currently applied periprocedural anticoagulation has not been explored. We measured markers of fibrinolysis and endothelium activation before and after PVI with the second-generation cryoballoon (Cryo), pulmonary vein ablation catheter (PVAC-Gold), and irrigated radiofrequency (IRF).

Methods

Markers of fibrinolysis and endothelium activation in left atrial (LA) blood samples were measured in 31 patients before and after PVI (Cryo:10, PVAC-Gold: 7, IRF: 14). Periprocedural anticoagulation included uninterrupted vitamin K antagonist and iv heparin (ACT≥300 sec) during LA dwelling.

Results

Levels of D-dimer (median; interquartile range, mgFEU/L) increased with all techniques (PVAC: 0.34; 0.24–0.50 versus 0.70; 0.61–1.31; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAP complex level (ng/ml) increased after Cryo (247.3, 199.9–331.6 versus 270.9, 227.9–346.7; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAI-1 activity (%) decreased with the PVAC (1.931; 0.508–3.859 versus 0.735, 0.240–2.707; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; VWF antigen levels and FVIII activity increased after PVI with all the 3 techniques. The levels of soluble VCAM-1 (ng/ml) did not change after PVAC procedures, but increased after Cryo (542, 6; 428.5–753.1 versus 619.2; 499.8–799.0; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93;

Conclusion

PVI with contemporary ablation techniques and periprocedural antithrombotic treatment induces coagulation and endothelium activation of similar magnitude with different ablation methods.

Atrial Fibrillation Ablation with Multipolar Phased-Radiofrequency Catheter: The Learning Curve Effect for Procedural Parameters, but not for the Long-Term Outcome

BACKGROUND

Pulmonary vein isolation (PVI) is a routine treatment in atrial fibrillation (AF). Single-shot techniques were introduced to simplify the procedure. We analyzed time-dependent changes in procedural parameters, acute success, complication rates, and long-term outcomes during our initial experience with multipolar phased-radiofrequency (RF) ablation. Methods and Results: The first 126 consecutive patients (98 male; age: 58.8 ± 8.7 years) who underwent PVI with phased-RF ablation at our center were included in the study. Procedural parameters, complication rate, acute success and 12-month efficacy were compared in the first, second and third group of 42 consecutive patients. In all patients, 516/526 PVs were effectively isolated (98.1%), with no differences between the tierces (p = 0.67). Procedure (169.8 vs. 132.9 vs. 105.8 min, p < 0.0001), fluoroscopy (32.9 vs. 24.3 vs. 14.1 min, p < 0.0001) and left atrial dwell (83.0 vs. 61.9 vs. 51.4 min, p < 0.0001) times were significantly reduced with experience in tierces 1-3, respectively. In the 12-month follow-up, 60.3% of patients were arrhythmia-free with no differences between the tierces (p = 0.88). In multivariate analysis, the relapse in the blanking period (p < 0.0001), time from AF diagnosis (p = 0.004) and left atrial diameter (p = 0.012) were the only independent predictors of AF recurrence.

CONCLUSIONS

The learning curve effect was demonstrated in procedural parameters, but not in the complication rate nor the long-term success of PVI with phased-RF technique. The relapse in the blanking period was the strongest predictor of treatment failure in long-time observation.

Silent cerebral lesions and cognitive function after pulmonary vein isolation with an irrigated gold-tip catheter: REDUCE-TE Pilot study

Introduction

Stroke is one of the most feared complications during catheter ablation of atrial fibrillation (AF). While symptomatic thromboembolic events are rare, magnetic resonance imaging (MRI) may identify asymptomatic (ie, silent) cerebral lesions (SCLs) following pulmonary vein isolation (PVI) procedures.

Methods and Results

The REDUCE‐TE Pilot was a prospective multicenter, single‐arm observational study investigating the incidence of SCL in patients with symptomatic paroxysmal AF undergoing PVI with a novel gold‐tip, externally irrigated ablation catheter. After ablation, cerebral diffusion‐weighted MRI and a postablation follow‐up were performed at 1 to 3 days after the ablation procedure. A neurocognitive test was done before and after ablation. The primary study endpoint was the occurrence of one or more new SCLs. Secondary study endpoints included neurocognitive status, procedural success rate, and periprocedural complications including symptomatic thromboembolic events. A total of 104 patients were enrolled (69% male, mean age: 61.5 ± 9.7 years, mean CHA₂DS ₂‐VASc score: 1.7 ± 1.2). Postprocedural MRI examination was performed in 97 patients, and in nine of them (9.3%; 95% CI: 4.3‐16.9%) a total of 11 SCLs were detected. Univariate analyses did not reveal any significant predictor for new SCLs. Nonsignificant trends were observed for low activated clotting time during ablation and for international normalized ratio value outside the range of 2 to 3 at ablation. There was no evidence of significant deterioration of neurocognitive function after PVI. In four patients, a pericardial tamponade was noted but all patients fully recovered during follow‐up.

Conclusions

Ablation of AF using a novel gold‐tip, externally irrigated ablation catheter, resulted in SCLs in approximately one out of 10 patients without a measurable effect on neurocognitive function.

Asymptomatic Cerebral Infarction During Catheter Ablation for Atrial Fibrillation: Comparing Uninterrupted Rivaroxaban and Warfarin (ASCERTAIN)

OBJECTIVES

This randomized study compared uninterrupted rivaroxaban therapy with warfarin therapy as prophylaxis against catheter ablation (CA)-induced asymptomatic cerebral infarction (ACI) and identified the risk factors of rivaroxaban.

BACKGROUND

The reported incidence of ACI during CA for atrial fibrillation (AF) remains at 10% to 30%, and periprocedural oral anticoagulation could affect this incidence.

METHODS

Patients with nonvalvular AF undergoing radiofrequency CA were randomly assigned to receive either uninterrupted rivaroxaban or warfarin as periprocedural anticoagulation therapy. CA was performed after at least 1 month of adequate anticoagulation. Cerebral magnetic resonance imaging (MRI) was performed within 2 weeks before and 1 day after CA to detect ACI.

RESULTS

A total 132 patients were enrolled; 127 (median: 60.0 years of age; 83.5% males; 64.6% incidence of paroxysmal AF) complied with the study protocol and were analyzed; 64 patients received rivaroxaban, and 63 patients received warfarin. The rates of CA-induced ACI in the rivaroxaban group (15.6% [10 of 64 patients]) were similar to those in the warfarin group (15.9% [10 of 63 patients]; p = 1.000). No thromboembolic events developed; no differences in major or nonmajor bleeding rates were observed between the 2 drug groups (3.1% vs. 1.6%, respectively, or 18.8% vs. 19.0%, respectively). Multiple regression analysis indicated that the presence of deep and subcortical white matter hyperintensity (p = 0.002; odds ratio [OR]: 5.323) and the frequency of cardioversions (p = 0.016; OR: 1.250) were associated with the incidence of ACI.

CONCLUSIONS

No notable differences were found between the incidence of CA-induced ACI in the rivaroxaban group and that in the warfarin group in this randomized study.

Comparing learning curves of two established "single-shot" devices for ablation of atrial fibrillation

PURPOSE

We compared the contour of learning curves of two "single-shot" devices used for pulmonary vein isolation (PVI) for safety and procedural data.

METHODS

We performed a retrospective analysis comparing the first 60 PVI performed at our center using a pulmonary vein ablation catheter (PVAC) array (39 male, mean age 57 years, 42 paroxysmal AF) to the first 60 first PVI using the Cryoballoon (44 male, mean age 59 years, 22 paroxysmal AF). Both groups were further divided into tertiles, where T1 regroups the first 20 ablations, T2 the following 20, and T3 the last 20 ablations.

RESULTS

The mean total procedure time was reduced by 24 min between T1 and T3 for the PVAC and 15 min for the Cryoballoon (p = 0.01). Fluoroscopy increased by 5 min, total ablation time was reduced by 7 min for PVAC (p = 0.02), and both times decreased respectively by 7 and 1 min for the Cryoballoon (p = ns). In the PVAC group, a mean rate of 0.16 (T1: n = 5; T2: n = 2; T3: n = 3) complications was observed while a rate of 0.16 (T1: n = 2; T2: n = 3; T3: n = 4) occurred in the CRYO group (p = ns). Severe complications defined as stroke, pericardial tamponade with need of pericardiocentesis and phrenic nerve palsy occurred in n = 4 in both groups (6.6%).

CONCLUSIONS

With either of the systems, no significant differences in the effect of the learning curve on the occurrence of adverse events were observed. However, the PVAC array seemed to have a steeper learning curve for procedure, as well as fluoroscopy time.

Comparison of the Efficacy of PVAC® and nMARQ™ for paroxysmal atrial fibrillation

Pulmonary vein isolation (PVI) has become the mainstay of therapy for atrial fibrillation (AF) and one of the most frequently performed procedures in the cardiac electrophysiology laboratory. PVI by a single-tip radiofrequency (RF) ablation catheter remains a complex and time-consuming procedure, especially in centers with limited experience. In order to simplify the PVI procedure, to shorten it and reduce the complication rate, circular multi-electrode catheters were introduced for simultaneous mapping and ablation. The common concept of these "single-shot" AF ablation technologies is the creation of circular lesions for PVI by placing the ablation device at the antrum of the pulmonary veins without the need for continuous repositioning. In this review we describe the main features of two circular non-balloon ablation catheters- PVAC^®, which is based on the phased RF, duty-cycled ablation technology, and nMARQ^™, the irrigated multi-electrode electro-anatomically guided catheter - and compare the clinical outcomes of these technologies, mainly for paroxysmal AF patients, based on current available data.

Pulmonary Vein Isolation with the Multipolar nMARQ™ Ablation Catheter: Efficacy And Safety In Acute And Long-Term Follow Up

Pulmonary vein isolation (PVI) is an established therapy for atrial fibrillation (AF). One challenge in the catheter-based treatment of this arrhythmia is to develop an effective and safe ablation approach to achieve durable and consistent lesions around the PVs. The multipolar irrigated radiofrequency (RF) ablation catheter nMARQ^TM was designed as a single-shot device with the aim to achieve these goals. This article reviews the current literature with respect to acute- and long- term success rates after PVI with this circular mapping and ablation device. Furthermore, since this device recently became discredited to potential lethal complications, we will also focus on the data available on safety issues with this ablation system.

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.

A 5-year clinical follow-up after duty-cycled phased RF ablation of paroxysmal atrial fibrillation

PURPOSE

Catheter radiofrequency ablation (RFA) is an effective treatment for symptomatic paroxysmal atrial fibrillation (AF). It has been demonstrated that the multielectrode pulmonary vein ablation catheter (PVAC) has favourable outcomes at 6-12 months post-ablation, but there are only few studies with a long-term follow-up.

METHODS

We retrospectively reviewed 77 consecutive PVAC procedures in our centre, from November 2007 to December 2012. RFA was attempted in patients with symptomatic paroxysmal AF (mean age 58.7 ± 9.8 years, 50 men (64.9 %). The ablation strategy consisted of circumferential pulmonary vein isolation (CPVI) with the PVAC system. A questionnaire was used over the follow-up period to assess the efficacy of AF ablation. Success was defined as freedom from AF/atrial flutter or atrial arrhythmia for a period ranging from 3 to 12 months or more.

RESULTS

Seventy-seven patients were included with paroxysmal AF. The mean duration of the procedure was 99.6 ± 26 min and fluoroscopy time 19.4 ± 6.8 min. Time of RFA was 22.4 ± 5.8 min. Acute complication rate was 10.4 % (the most frequent was vascular injury for 6 patients 7.8 %, 1 patient presented sepsis (1.3 %), 1 patient presented transient ischemic stroke). After a single procedure at a mean FU of 55 ± 11 months, 54/77 (70.1 %) patients were free of symptomatic AF.

CONCLUSIONS

These long-term results suggest that PVAC is an efficient system for CPVI of symptomatic paroxysmal AF.

First results and follow-up of a second-generation circular mapping and ablation catheter

PURPOSE

Pulmonary vein isolation with radiofrequency energy is widely used as a strategy for catheter ablation of atrial fibrillation (AF). Anatomically designed catheters have been developed to increase the efficiency of AF ablation procedures. The second-generation circular ablation catheter, PVAC GOLD, was re-designed to improve energy delivery and mitigate emboli. We investigated the procedural efficiency, biophysics, and chronic efficacy of PVAC GOLD in patients with AF.

METHODS

We consecutively enrolled 40 patients (60 ± 11 years) with highly symptomatic, drug refractory AF. The first 20 patients were treated with the first-generation PVAC. The subsequent 20 patients were treated with the second-generation PVAC GOLD catheter. All patients were followed up at 3, 6, and 12 months.

RESULTS

All 164 targeted PVs were successfully isolated. Ablations performed with PVAC GOLD showed a significant reduction in total number of ablations needed for PVI, fluoroscopy, and procedure times compared to PVAC (34.7 ± 7.0 vs. 27.0 ± 6.5; p = 0.009), fluoroscopy (29.5 ± 9.5 vs. 23.4 ± 7.0; p = 0.026), and procedure time (93.8 ± 18.9 vs. 83.1 ± 10.6; p = 0.033). PVAC GOLD showed improved biophysics including a reduction of low power ablations and an increase in mean effective energy delivery. At 12 months follow-up, AF recurrence rates were comparable in the two groups (35 vs. 30 %; p = 0.735). There were no adverse events.

CONCLUSIONS

The redesigned PVAC GOLD catheter demonstrates a reduction in radiofrequency ablation and procedure time and improved biophysics while maintaining chronic efficacy compared to the first-generation PVAC.