Search

Background: Validation of pulmonary vein (PV) isolation (PVI) using only the Achieve catheter following cryoballoon ablation (CBA) is imperfect since pulmonary vein potentials (PVP) can be recorded in only 50-85% of the veins and residual PVP are found in up to 4.3-7.6% of the isolated veins in remapping studies., Objective: To study if addition of electroanatomical mapping to Achieve catheter-guided CBA is superior for PVI., Methods: One hundred patients were randomized between Achieve catheter-guided CBA (control group; N = 50) and Achieve catheter-guided CBA with additional EnSite voltage maps performed pre- and post-CBA (Achieve Plus group; N = 50). Confirmation of PVI was done by circular mapping catheter (CMC) and EnSite mapping by a second blinded operator., Results: Despite apparent PVI in all PVs after CBA, incomplete PVI was present in 0 out of 50 patients (0%) and 0 out of 204 PVs in the Achieve Plus group versus 6 patients out of 50 (12%; P = 0.012) and 6 out of 203 PVs (3%; P = 0.013) in the control group. All 6 non-isolated PVs could be successfully isolated by additional cryoapplications. Procedure time was longer in the Achieve Plus group (75.76 ± 21.65 vs 66.06 ± 16.83 min; P = 0.014) with equal fluoroscopy times (14.85 ± 6.41 vs 14.33 ± 8.55; P = 0.732)., Conclusion: The addition of electroanatomical EnSite mapping to the Achieve catheter improves the PVI rate of CBA and could be considered for future use. Design and Results of the Achieve Plus study. The Achieve Plus study shows that the addition of electro-anatomical EnSite mapping to the Achieve catheter improves PVI rate of CBA and could be considered for future use. See text for further explanation., Abbreviations: CBA: cryoballoon ablation; PVI: pulmonary vein isolation., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Balloon catheters have been developed to facilitate pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF). We sought to compare the safety and efficacy of the cryoballoon (CB) and the laserballoon (LB) in a pilot study., Methods and Results: One hundred and forty patients with drug-refractory PAF were prospectively allocated in a 1:1 fashion to undergo a PVI procedure with the 28 mm CB or the LB and were followed for 12 months using 3-day Holter ECG recording. The primary efficacy endpoint was a documented AF recurrence ≥ 30 seconds between 90 and 365 days after the index ablation. In total, 269 of 270 PVs (99.6%) and 270 of 273 PVs (98.9%) were acutely isolated in the CB and LB group, respectively. Mean procedural time was 136 ± 30 minutes for the CB group and 144 ± 33 minutes for the LB group (P = 0.13). Mean fluoroscopy time was longer in the CB group (21 ± 9 minutes vs 15 ± 6 minutes; P < 0.001). During 12 months follow-up, 37% of patients in the CB group and 27% in the LB group experienced an AF recurrence (P = 0.18). Phrenic nerve palsies occurred in 5.7% (CB) and 4.2% (LB) of patients, respectively., Conclusion: Balloon catheters are a viable option to safely perform a PVI procedure in patients with drug-refractory PAF. Ninety-nine percent of PVs may be acutely isolated with a single balloon catheter. The AF free survival rate after a single ablation procedure was not statistically different between groups., (© 2013 Wiley Periodicals, Inc.)

Introduction: Pulmonary vein isolation (PVI) is a challenging procedure most often requiring sophisticated technical aids such as electroanatomical mapping, double transseptal access, and the use of a circular mapping catheter. We sought to develop a PVI strategy solely based on visual guidance with a single ablation device as well as a single transseptal puncture using the endoscopic ablation system (EAS)., Methods and Results: In 35 patients with drug-refractory atrial fibrillation (18 male, mean age: 62 ± 9 years) ablation was performed. PVI was achieved in 96 of 137 PVs (70%) purely by visually guided circular ablation. Predictors of acute isolation were the degree of PV occlusion by EAS as well as the number of catheter repositionings but not total ablation energy or the number of laser applications. Conduction gaps were detected at sites with suboptimal occlusion as well as esophageal temperature elevations. Further EAS ablation resulted in a 98% acute isolation rate. Mean procedure and fluoroscopy times were 154 ± 38 minutes and 16 ± 6 minutes, respectively. Between the first and last 12 cases, a reduction in procedure times (175 ± 48 minutes vs 138 ± 26 minutes; P = 0.05) was observed. One pericardial tamponade and 1 right-sided phrenic nerve palsy occurred. During a median follow-up of 266 days (q-q3: 218-389), 27 of 35 patients (77%) remained free of any tachyarrhythmia recurrence off antiarrhythmic drugs., Conclusions: Sequential PVI based solely on endoscopic visual information with a single device and a single transseptal puncture is feasible. Optimal PV occlusion and few controlled repositionings facilitate PVI., (© 2012 Wiley Periodicals, Inc.)

In cryoballoon ablation (CBA), a contrast medium is commonly used to confirm balloon occlusion of the pulmonary veins (PVs). However, a contrast medium cannot always be used in patients with renal dysfunction and allergy. The present study aimed to assess the efficacy and safety of CBA without the use of a contrast medium. We retrospectively examined consecutive patients with paroxysmal atrial fibrillation (PAF) who underwent first-time CBA. We compared the procedural results and outcomes in patients for whom a contrast medium was used (contrast group) and those from whom a contrast medium was not used (non-contrast group). In the non-contrast group, we used saline injection on the intracardiac echocardiography and pressure wave monitoring for PV occlusion. Fifty patients (200 PVs) and 22 patients (88 PVs) underwent CBA with and without a contrast medium, respectively. The success rate of PV isolation with CBA alone was 93% and 90% in the non-contrast and contrast groups, respectively (p = 0.40). The fluoroscopy time and nadir temperature were significantly lower in the non-contrast group as compared to that in the contrast group. The recurrence rate 1 year after ablation did not differ between the two groups (18% vs. 18%, p > 0.99). Furthermore, the number of reconnected PVs in patients with recurrence was significantly lower in the non-contrast group than in the contrast group (6% vs. 36%, p = 0.017). In conclusion, CBA using the intracardiac echocardiography and pressure monitoring approach without the use of a contrast medium was safe and efficient., (© 2021. Springer Japan KK, part of Springer Nature.)

Background: The endoscopic ablation system (EAS) is an established ablation device for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). The novel X3 EAS is now equipped with a contiguous circumferential ablation mode (RAPID mode)., Aim: To determine the feasibility of single-shot fashioned ablation using X3., Methods: Consecutive patients who underwent AF ablation using X3 were enrolled. We assessed the acute procedural data focusing on "Single-sweep PVI" defined as successful PVI with a single RAPID mode energy application, and on "first-pass isolation" defined as successful PVI after initial circular lesion set., Results: One hundred AF patients (56% male, age: 68 ± 10 years, 66% paroxysmal AF) were analyzed. A total of 379 of 383 PVs (99%) were isolated with X3. Single-sweep PVI and first-pass-isolation were achieved in 214 PVs (56%) and in 362 PVs (95%), respectively. Single-sweep PVI rates varied across PVs with higher rates at the superior PVs (61.2% vs. inferior PVs: 49.5%, p = .0239) and at PVs with maximal ostial diameter <24 mm (57.6% vs. >24 mm: 36.8%, p = .0151). The mean total procedure and fluoroscopy times were 43.0 ± 10 and 4.0 ± 2 min, respectively. In none of the patients an acute thromboembolic event (stroke or transient ischemic attack) or a pericardial effusion/tamponade occurred. A single transient phrenic nerve palsy was observed., Conclusion: The new X3 EAS allows for single-shot fashioned ablation in terms of single-sweep PVI in half or more of PVs. The new RAPID ablation mode leads to an improved rate of first-pass isolation associated with very short procedure times without compromising safety., (© 2021 Wiley Periodicals LLC.)

Electrophysiological studies have rarely evaluated the sites prone to pulmonary vein (PV) conduction gap during cryoballoon ablation (CBA) for atrial fibrillation (AF). In addition, no studies have analyzed the sequence of PV potentials just before PV isolation during CBA for AF. Of the 238 patients who underwent first-time CBA for paroxysmal AF, 115 PVs of 29 patients who underwent repeat session due to recurrence after the procedure were retrospectively evaluated in the study. We evaluated the disappearance pattern of PV potential and PV reconnection on intracardiac electrograms and investigated whether the conduction gap site of the PV was related to the last remaining earliest PV potential (EP) and sequence pattern during the first-time CBA. Time to isolation was observed in 81 PVs during the first-time CBA. At the repeat session, PV reconnection was only observed in 22 of 81 PVs. PV potentials disappeared with sequence changes in 36 PVs and without sequence changes in 38 PVs. Multivariate analysis demonstrated that disappearance of PV potentials without change in the EP site but with delay or disappearance of other PV potentials was independently associated with PV reconnection (12/22 PVs [55%] vs. 4/59 PVs [6.8%]; odds ratio 14.4; 95% confidence interval 3.75-55.5; p < 0.001). In 19 of 22 (86%) reconnected PVs, PV conduction gap sites at repeat ablation corresponded with the last remaining EP sites during first-time CBA. In conclusion, disappearance pattern of the PV potential and the last remaining EP during the CBA can predict PV reconnection and gap site.

Purpose: The purpose of the study was to evaluate the impact of left atrial posterior wall isolation (LAPWI) in addition to pulmonary vein isolation (PVI) vs PVI alone, performed using CB-A, in patients with PAF on a midterm follow-up of 12 months., Methods: Eighty consecutive patients indicated to index cryoballoon ablation (CB-A) for the treatment of drug resistant PAF were included. The first 50 (62.5%) underwent PVI only, and the following 30 patients (37.5%) underwent LAPWI + PVI., Results: Acute isolation was achieved in all PVs in both groups. The LAPW was successfully isolated in 29 out of 30 (97%) patients; in the remaining patient, adjunct radiofrequency ablation was required. The total procedure time and the mean fluoroscopy time were significantly shorter in patients who underwent PV isolation only (p < 0.001). The freedom from atrial fibrillation (AF) at 12 months was not significantly different between the 2 groups (LAPW + PVI = 90% vs PVI = 88%) (log-rank p = 0.816)., Conclusion: LAPW ablation in addition to PVI by the means of CB-A does not seem to reduce the risk of AF recurrence if compared with the standard PVI on a midterm follow-up of 12 months., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Catheter ablation is an established treatment option for atrial fibrillation (AF), and pulmonary vein isolation (PVI) has become the gold standard in AF ablation. AF recurrence after PVI remains an important clinical problem. Recovery of conduction from the pulmonary veins (PVs) is considered the dominant mechanism for AF recurrence in paroxysmal AF. However, the underlying mechanism of AF recurrence after PVI is more complex in patients with persistent and longstanding persistent AF. Different ablation technologies and energy sources have been developed aimed at improving lesion quality and durability with an acceptable safety profile. Novel technologies are under evaluation which have a great potential to produce permanent PVI after a single ablation procedure. However, clinical value of these novel devices needs to be tested in adequately powered randomized controlled trials. In this article, we review the history of catheter ablation for AF and discuss the present and future ablation technologies.

Introduction: Lesion size and continuity in dragging laser balloon (LB) ablation, which may enable fast and durable pulmonary vein isolation for atrial fibrillation, are unknown. We evaluated the differences in size and continuity of linear lesions formed by dragging ablation and conventional point-by-point ablation using an LB in vitro model., Methods and Results: Chicken muscles were cauterized using the first-generation LB in dragging and point-by-point fashion. Dragging ablation was manually performed with different dragging speeds (0.5-2°/s) using an overlap ratio of the beginning and last site during one application at 12 W/20 s and 8.5 W/30 s. Point-by-point ablation was performed with 25% and 50% overlap ratios at six energy settings (5.5 W/30 s to 12 W/20 s). Lesion depth, width, and continuity were compared. Lesion continuity was assessed by the surface and deep visible gap degree categorized from 1 (perfect) to 3 (poor). Twenty lesions were evaluated for each ablation protocol. Lesion depth and width in dragging ablation at high power (12 W) were comparable with most measurements in point-by-point ablation. Lesion depth and width were smaller at faster-dragging speed and lower power (8.5 W) in dragging ablation. The surface visible gap degree was better in dragging ablation at all dragging speeds than a 25% overlapped point-by-point ablation (p < .001)., Conclusion: Dragging LB ablation at high power provides deep and continuous linear lesion formation comparable with that of point-by-point LB ablation. However, lesion depth and width depending on the dragging speed and power., (© 2020 Wiley Periodicals LLC.)

Aims: Systematic data on phrenic nerve palsy (PNP) associated with contemporary balloon ablation techniques (cryoballoon [CBA] vs laser balloon [LBA]) are sparse. We aimed to investigate the incidence, characteristics, and clinical recovery course in patients with PNP who underwent CBA or LBA., Methods and Results: A total of 2433 consecutive patients who underwent balloon-based pulmonary vein isolation (CBA: n = 1720 and LBA: n = 713) were retrospectively identified. PNP was classified into (a) transient (recovery before discharge) or (b) persistent (within 6 months, 6-12 months, and >12 months) according to clinical recovery course. In general, PNP occurred significantly more often in CBA 71/1720 (4.2%) than LBA 11/713 (1.5%) (P = .003). The rate of transient PNP was significantly higher in CBA (3.0%, n = 45) than LBA (0.1%, n = 1, P = .004). The rate of persistent PNP did not significantly differ between two groups (CBA: 1.2% vs LBA: 1.4%, P = .89). The rate of persistent PNP which recovered within 6 months was similar (CBA: 17.4% vs LBA 18.2%, P = 1.000). However, the rates of persistent PNP which recovered within 6 to 12 months (CBA: 2.9% vs LBA 27.3%, P = .0171) and more than 12 months (CBA: 7.3% vs LBA 45.5%, P = .0034) were significantly higher in LBA., Conclusion: PNP occurred more often in CBA than LBA, however, the majority of PNP in CBA was transient whereas the majority of PNP in LBA was persistent. Either balloon technology is not superior in terms of long-term PNP., (© 2020 Wiley Periodicals LLC.)

Pulsed field ablation (PFA) is an innovative approach in the field of cardiac electrophysiology aimed at treating cardiac arrhythmias. Unlike traditional catheter ablation energies, which use radiofrequency or cryothermal energy to create lesions in the heart, PFA utilizes pulsed electric fields to induce irreversible electroporation, leading to targeted tissue destruction. This state-of-the-art review summarizes biophysical principles and clinical applications of PFA, highlighting its potential advantages over conventional ablation methods. Clinical data of contemporary PFA devices are discussed, which combine predictable procedural outcomes and a reduced risk of thermal collateral damage. Overall, these technological developments have propelled the rapid evolution of contemporary PFA catheters, with future advancements potentially impacting patient care. [ABSTRACT FROM AUTHOR]

Atrial fibrillation, representing the most prevalent sustained cardiac arrhythmia, significantly impacts stroke risk and cardiovascular mortality. Historically managed with antiarrhythmic drugs with limited efficacy, and more recently, catheter ablation, the interventional approach field is still evolving with technological advances. This review highlights pulsed field ablation (PFA), a revolutionary technique gaining prominence in interventional electrophysiology because of its efficacy and safety. PFA employs non-thermal electric fields to create irreversible electroporation, disrupting cell membranes selectively within myocardial tissue, thus preventing the non-selective damage associated with traditional thermal ablation methods like radiofrequency or cryoablation. Clinical studies have consistently shown PFA's ability to achieve pulmonary vein isolation—a cornerstone of AF treatment—rapidly and with minimal complications. Notably, PFA reduces procedure times and has shown a lower incidence of esophageal and phrenic nerve damage, two common concerns with thermal techniques. Emerging from oncological applications, the principles of electroporation provide a unique tissue-selective ablation method that minimizes collateral damage. This review synthesizes findings from foundational animal studies through to recent clinical trials, such as the MANIFEST-PF and ADVENT trials, demonstrating PFA's effectiveness and safety. Future perspectives point towards expanding indications and refinement of techniques that promise to improve AF management outcomes further. PFA represents a paradigm shift in AF ablation, offering a safer, faster, and equally effective alternative to conventional methods. This synthesis of its development and clinical application outlines its potential to become the new standard in AF treatment protocols. [ABSTRACT FROM AUTHOR]

Copyright of Herz is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Visually guided laser balloon (LB) catheter has been an established modality dedicated for pulmonary vein (PV) isolation in patients with atrial fibrillation. The newly updated version of this novel device has technically evolved recent years. This review will summarize the contemporary technical evolution of LB catheter. Available efficacy outcomes and the historical change of ablation style will be evaluated. Furthermore, the future perspectives for clinical practice are discussed. The initial LB ablation system provided comparable clinical results in PV isolation with other technologies, but with a unique strategical concept enabling the direct visualization of the tissue to cauterize. With multigenerational development, the LB catheter has been equipped with more compliant balloon for favorable PV occlusion and a robotically motor driven continuous ablation mode (RAPID mode). These technical innovations changed the concept of the ablation strategy using LB catheter as 'point-by-point' into 'single-shot' fashion. The remaining tasks are further improvements such as equipping with real-time recording system of intracardiac electrogram, durable structured balloon and the instrument for visualizing the cauterization area in a 360-degree panoramic view, which includes potential possibilities to develop this novel device to the more optimal device for PV isolation. [ABSTRACT FROM AUTHOR]

Aims: Balloon-based technologies have been developed to simplify catheter ablation of atrial fibrillation (AF), to improve the clinical outcome of the procedure and to achieve durable pulmonary vein isolation (PVI). The objective of this study is to evaluate the safety and efficacy of second-generation laser balloon (LB2) ablation in the treatment of AF using a continuous cardiac rhythm monitoring strategy. Atrial tachyarrhythmias (ATas) recurrences were assessed with implantable cardiac monitors (ICMs) or devices.Methods and Results: All patients underwent LB2 ablation procedure. The primary endpoint was the first recurrence of any, >5.5 and >24 h duration ATas after the blanking period (90 days). In-hospital visits were performed at 3, 6, and 12 months. Seventy-three patients (68% male, mean age 59.8 ± 11.3) were included in the study. The average procedure, fluoroscopy, and laser ablation times were 81.5 ± 30.1, 21.5 ± 12.4, and 33.8 ± 9.7, respectively. All PVs were isolated using the LB2 with no need of touch-up using focal catheters. No major complications occurred during or after the procedures. The one-year freedom from recurrences was 66.9% (95% CI: 57.0-76.7%), 81.0% (69.5-88.5%), and 86.8% (76.1-92.9%) considering any, 5.5-h and 24-h cut-off duration, respectively. At 3, 6, and 12 months, any ATas was recorded in 22%, 32%, and 25% of patients, with a ≥5% arrhythmic burden documented in 4%, 5%, and 3%, respectively. Few patients reported AF-related symptoms (7%, 8%, and 5%).Conclusion: LB2 ablation is a safe and effective procedure, showing a high freedom from recurrences and low arrhythmic burden as documented by a continuous rhythm monitoring strategy. [ABSTRACT FROM AUTHOR]

Aims: Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted ablation strategy for rhythm control in atrial fibrillation (AF). We describe efficacy and safety in a high volume centre with a long experience in the use of the second-generation CB (CB2).Methods and Results: Consecutive paroxysmal AF (PAF) or persistent AF (persAF) patients undergoing CB2-PVI were enrolled. Procedural data, efficacy, and safety issues were systematically collected. The 28 mm CB2 was used in combination with an inner lumen spiral catheter, a luminal oesophageal temperature (LET) probe was used with a cut-off of 15°C, the phrenic nerve (PN) monitored during septal PVs ablation. Freeze duration was mainly set at 240 s with a bonus application in case of delayed time-to-isolation (TTI > 75 s). A total of 1017 CB2 procedures were analysed (58% male, 66 ± 12 years old, 70% with PAF). 3964 PVs were identified, 99.8% PVs isolated using solely the 28 mm CB. Mean procedure time was 69 ± 25 min, TTI during the first application was recorded in 77% of PVs after a mean of 48 ± 31 s. We recorded 0.2% cardiac tamponade, 4.8% PN injury (1.6% of PN palsy), and 19% of LET < 15°C. Among 725 patients with follow-up data, 84% with PAF and 75% with persAF were in stable SR at 1 year. Shorter freezing duration and longer TTI were procedural predictors for recurrence.Conclusion: Cryoballoon procedures are fast and associated with a benign safety profile. Shorter TTI and longer freeze durations are associated with sinus rhythm during follow-up. [ABSTRACT FROM AUTHOR]

Introduction: The influence of power (Watt [W]) and total energy (Joule [J]) on lesion size and the optimal overlap ratio remain unclear in laser balloon (LB) ablation for atrial fibrillation. We aimed to evaluate lesion size and visible gaps after LB ablation with various energy settings and different overlap ratios in vitro model. Methods and Results: Chicken muscles were cauterized using the first‐generation LB with single applications of full and a half duration of six energy settings (5.5 W/30 seconds [165 J] to 12 W/20 seconds [240 J]) and varying power (5.5‐12 W) at the constant total energy (160 J). Three overlapped ablations with different ratios (25% and 50%) for each energy setting were also performed to evaluate the visible gap degree categorized from 1 (perfect) to 3 (poor). Twenty lesions were evaluated for each energy setting. In single applications of full duration, lesion depth, lesion volume, and maximum lesion diameter increased according to the total energy (all, P < .001) and were greater than in those of half duration in each energy setting (all, P < .05). However, applications with larger power created larger lesion volume and maximum lesion diameter at constant total energy (P < .05). The visible gap degree was better in all energy settings with 50% overlapped ablation than in those with 25% (all, P < .001). Conclusion: Lesion size depends not only on power but also on total energy in the LB ablation. Sufficiently overlapped ablations allow continuous lesion formation. [ABSTRACT FROM AUTHOR]

Background: The procedural data of pulmonary vein (PV) isolation (PVI) for patients with atrial fibrillation using the second‐generation laser balloon (LB2), which became available recently, remains unclear and were evaluated. Methods: Thirty consecutive patients (116 PVs) underwent PVI using LB2 (LB2 group) and were matched to 30 patients (116 PVs) treated with the first‐generation laser balloon (LB1 group). The left atrial isolated surface area (ISA) (ratio of the total isolated antral surface area excluding PV to the total isolated antral surface area including the posterior wall) was also measured after LB2 PVI. Results: PVI was achieved in 103/116 (89%) PVs and 108/116 (93%) PVs in the LB2 and LB1 groups, respectively, after the initial circular ablation (P = 0.360) and in 115/116 (99%) PVs and 116/116 (100%) PVs in the LB2 and LB1 groups, respectively, at the end of the procedure (P = 1.000). PV occlusion grade, categorized by the degree of PV occlusion, was significantly better in the LB2 group than in the LB1 group (P < 0.001). Zero rotational maneuver was applicable in 23/116 (20%) PVs and 8/116 (7%) in the LB2 and LB1 groups, respectively (P = 0.007). There was no significant difference in the procedural time, fluoroscopic time, or complications. The mean ISA after LB2 PVI was 53 ± 14%. The application number was the only independent predictor of successful PVI after initial circular LB2 ablation (adjusted odds ratio 0.860; 95% confidence interval 0.764–0.968; P = 0.013). Conclusion: LB2 displays favorable PV occlusion characteristics and enables more zero rotational maneuvers. [ABSTRACT FROM AUTHOR]

Background: The left atrial appendage (LAA) has been identified as a potential source of atrial fibrillation (AF) and has been described as the "fifth" pulmonary vein (PV). We report our initial experience in LAA isolation (LAAI) using the cryoballoon (CB) and data on durability of CB‐LAAI. Methods: Patients treated with a CB‐LAAI were retrospectively identified. Six weeks after electrical LAAI, patients were scheduled for staged percutaneous LAA closure. During the second procedure, a subset of patients underwent invasive remapping of the LAA. Results: A total of 32 patients (21 males, 68 ± 10 years old) were treated with CB‐LAAI. Acute LAAI was achieved in 29 of 32 (91%) patients: single‐shot LAAI was observed in 18 of 32 (56%) patients. Acute procedural sustained LAAI was related with a significantly shorter time to LAAI (sustained LAAI: 84 ± 50 s vs nonsustained LAAI: 166 ± 76 s, P = 0.004). Mean procedure and fluoroscopy time were 61 ± 29 and 8 ± 6 min, respectively. One left‐sided phrenic nerve palsy occurred. In 25 of 32 (78%) patients, a second procedure for percutaneous LAA closure device implantation was performed. In 22 patients, persistency of LAAI was tested: durable LAAI was documented in 16/22 patients (73%). Conclusion: In the present report, CB LAA isolation followed by staged LAA closure appeared to be safe and feasible but more data are required. Time to LAAI played a role in predicting acute sustained LAAI rate. CB LAA ablation leads to 73% of durable LAA isolation. [ABSTRACT FROM AUTHOR]

Background: Laser balloon (LB) and cryoballoon (CB) ablation are two balloon-based catheter ablation technologies used for atrial fibrillation (AF) ablation in recent years. However, the efficacy and the safety of LB ablation in comparison to CB ablation remained indeterminate. We sought to compare these two technologies by conducting meta-analysis of previous studies using both the CB and LB ablation systems for AF ablation.Methods: We searched electronic scientific databases for studies of LB vs. CB ablation in AF patients. The procedural efficacy was assessed by the success of acute pulmonary vein isolation (PVI) and the 12-month recurrence of any atrial arrhythmia, and the safety was evaluated by the risk of procedure-related complications.Results: A total of 595 participants (LB, n = 292 vs. CB, n = 303) from eight studies were included in this meta-analysis. Risk of acute PVI failure (risk ratio, RR 95% confidence interval [95% CI] = 2.55 [0.86-7.56], P = 0.09) and atrial arrhythmia recurrence in 12 months (RR [95% CI] = 0.91 [0.64-1.28], P = 0.59) were comparable between LB vs. CB ablation, and LB ablation tended to be more effective than CB ablation in paroxysmal AF patients (RR [95% CI] = 0.70 [0.47-1.03], P = 0.07). Risk of procedure-related complications was similar while LB ablation showed slightly higher risk without statistic significance (LB 13.9% vs. CB 9.3%, RR [95% CI] = 1.52 [0.88-2.64], P = 0.14). Compared with CB ablation, LB ablation led to longer procedure duration (weighted mean differences WMD [95% CI] =29.7 [15.8-43.7], P < 0.001) while similar fluoroscopy duration was observed between these two ablation devices (WMD [95% CI] = - 1.99[- 6.46-2.47], P = 0.38).Conclusions: LB ablation has a trend toward higher procedural efficacy compared with CB ablation in paroxysmal AF patients. However, longer procedure duration and a statistically non-significant trend of more procedure-related complications were also observed in patients ablated by LB. Further larger comparative randomized trials are warranted to disclose the impact of LB compared with CB for ablation of AF. [ABSTRACT FROM AUTHOR]

Background: It remains unclear whether left atrial low‐voltage area (LALVA) affects atrial tachyarrhythmia recurrence after laser balloon pulmonary vein isolation (PVI) for atrial fibrillation (AF). We prospectively evaluated the outcome of laser balloon PVI in patients with and without LALVA (≤ 0.5 mV) together with surface/intracardiac electrophysiological criteria. Methods: One hundred consecutive paroxysmal/persistent AF patients underwent laser balloon PVI. The relative extent of LALVA (extent of LALVA/left atrial surface area × 100 [%]: rLALVA), total p‐wave duration in lead II (PWD), and time interval from the beginning of p‐wave to the local activation in left atrial appendage (TTLAA) were assessed. Patients were divided into patients with LALVA (group A: 23 patients) and those without LALVA (group B: 77 patients). The primary endpoint was freedom from atrial tachyarrhythmia after the blanking periods. Results: Complete PVI was achieved in 99/100 (99%) patients. PWD and TTLAA were longer in group A (both, P < 0.001). During 12 months' follow‐up, survival free from atrial tachyarrhythmia recurrence was lower in group A (12/23 [52%] patients vs 67/77 [87%] patients, P < 0.001). Multivariate analysis identified rLALVA as the only independent predictor of atrial tachyarrhythmia recurrence. rLALVA correlated with PWD and TTLAA (r = 0.41, P < 0.001 and r = 0.60, P < 0.001, respectively). Receiver operating characteristic curve for rLALVA revealed PWD of 122 ms and TTLAA of 92 ms as the optimal cut‐off value. Conclusion: LALVA was associated with poorer outcome after laser balloon PVI. Patients may be identified by longer PWD and TTLAA. [ABSTRACT FROM AUTHOR]

Purpose: Phrenic nerve (PN) injury is a typical complication of cryoballoon ablation (CBA) of pulmonary veins. The PN function is monitored by palpating the abdomen during PN pacing, and freezing is prematurely terminated when a reduction in the diaphragm movement is recognized. This study aimed to investigate the efficacy and safety of a "pull-back" maneuver to prevent PN injury.Methods: A total of 284 patients were included, and the PN function was monitored by recording the diaphragmatic compound motor action potentials (CMAP) during the cryoballoon applications for pulmonary vein (PV) isolation. When the CMAP amplitude was reduced by more than 30% compared to the control, the "pull-back" maneuver (PBM) was undertaken to prevent PN injury.Results: The average CMAP amplitude significantly decreased from 0.81 ± 0.04 to 0.31 ± 0.21 (p < 0.01) mV during the cryoballoon applications of PVs in 92 PVs. The PBM was employed in all cases, and the average CMAP amplitude recovered to 0.87 ± 0.31 mV (p < 0.01) in 79 out of 92 PVs (85.9%), accomplishing the CBA. Cryofreezing had to be prematurely terminated due to failure of the PBM in 13 out of 92 cases (14.1%).Conclusions: The PBM was an effective maneuver to prevent PN injury by creating a distance between the PN and location of the cryoballoon. No adverse events were provoked by this procedure. [ABSTRACT FROM AUTHOR]

Aims Establishment of pulmonary vein isolation (PVI) during cryoballoon (CB) ablation is generally confirmed by use of an octapolar inner-lumen mapping catheter (Achieve®). The aim of this study is to evaluate the residual PV potential (PVP) using the conventional circular catheter after CB-PVI. Methods and results A total of 105 consecutive patients (418 PVs) with paroxysmal AF who underwent the initial CB-PVI were prospectively included in this study. Of those, 305 (73%) PVs with real-time recordings of PVP elimination by Achieve® catheter during successful PVI were included. After isolation of all 4 PVs, PV antral remapping by conventional circular mapping catheter was performed. After CB-PVI, residual PVP was detected in 4.3% (13/305) of PVs (1.2% of left-superior PV, 2.5% of left-inferior PV, none of right-superior PV, and 20% of right-inferior PV). Almost 60% of residual PV potential was located around the bottom portion of the right-inferior PV. In PVs with residual potential, PV trunk was shorter (12.7 ± 5.7 mm vs. 18.7 ± 7.9, P  = 0.001), minimal balloon temperature was higher (−46.6 ± 5.9 °C vs. −50.9 ± 8.2, P  = 0.02), and balloon warming time was shorter (35.6 ± 17.8 s vs. 50.0 ± 22.8, P  = 0.006) than those without. All residual potentials were eliminated by additional touch up ablation. After the initial ablation procedure, 1-year AF-free rate was 79.5%. Conclusion PV remapping after CB-PVI revealed residual antral PVP in 4.3% of PVs and in 20% of RIPVs in particular. The Achieve® catheter sometimes fails to detect complete PV antral isolation. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Cerebral events (CEs), including silent (SCEs), are a known complication of left atrial catheter ablation (LACA) in patients with atrial fibrillation. The aim of this prospective registry was to gain more information about CEs during laserballoon LACA and to reduce the risk of their occurrence. Methods and results: We enrolled 74 patients (age 61 ± 11 years; 74% male; CHA2DS2‐VASc 1.9 ± 1.4). Cerebral MRI (1.5 Tesla) was performed to detect CEs. ASPItest identified aspirin‐resistant patients (ARPs). All bleeding complications were recorded. Due to an initial high CE rate, we evolved our clinical procedure step‐by‐step arriving at an optimized protocol: –Group 1: heparin after single transseptal puncture (TP), activated clotting time (ACT) > 300 seconds (CE: 64.3%). –Group 2: heparin after double TP, ACT > 300 seconds; 2a without (CE: 45.5%, RRR: −29.2%) and 2b with additional intravenous aspirin (CE: 36.4%, RRR: −43.4%; excluding ARP: 30%, RRR: −53.3%). –Group 3: heparin before double TP, ACT > 350 seconds; 3a without (CE: 54.5%, RRR: −15.2%) and 3b with aspirin (CE: 18.5%, RRR: −71.2%; excluding ARP: 8.7%, RRR: −86.5%). Larger LA diameter > 44 mm (OR: 1.149, P  =  0.005) and no aspirin use (OR: 4.308, P  =  0.008) were CE risk factors in multivariate logistic regression. In those patients receiving aspirin, aspirin resistance (OR: 22.4, P  =  0.011) was an exceptionally strong risk factor. Conclusion: These data support the use of intravenous aspirin including monitoring of aspirin resistance in addition to ACT‐guided heparin. An optimized protocol of heparin before TP, double TP, and intravenous aspirin in non‐ARP resulted in a significantly lowered CE incidence and severity. [ABSTRACT FROM AUTHOR]

Aims: There is no objective, early indicator of occlusion quality, and efficacy of cryoballoon pulmonary vein isolation. As previous experience suggests that the initial cooling rate correlates with these parameters, we investigated the slope of the initial temperature drop as an objective measure.Methods and Results: A systematic evaluation of 523 cryoapplications in 105 patients using a serial ROC-AUC analysis was performed. We found the slope of a linear regression of the temperature-time function to be a good predictor (PPV 0.9, specificity 0.72, sensitivity 0.71, and ROC-AUC 0.75) of acute isolation. It also correlated with nadir temperatures (P< 0.001, adjusted R2= 0.43), predicted very low nadir temperatures, and varied according to visual occlusion grades (ANOVA P< 0.001).Conclusions: About 25 s after freeze initiation, the temperature-time slope predicts important key characteristics of a cryoablation, such as nadir temperature. The slope is the only reported predictor to actually precede acute isolation and thus to support decisions about pull-down manoeuvres or aborting a cryoablation early on. It is also predictive of very low nadir temperatures and phrenic nerve palsy and thus may add to patient safety. [ABSTRACT FROM AUTHOR]

Introduction The ablation strategy for atrial fibrillation (AF) despite pulmonary vein isolation (PVI) is controversial. Left atrial appendage isolation (LAAI) may contribute to improve outcome. We describe an ablation approach ('Maze-like'-LAAI) that (1) modifies the underlying LA substrate by linear ablation (2) eliminates the LAA as a putative AF trigger site and (3) incorporates an unambiguous procedural endpoint. The role of LAA closure (LAAC) after LAAI was investigated. Methods Patients with atrial tachyarrhythmias nonresponsive to PVI underwent a LAAI ablation procedure. LAAI was achieved by combining (a) an anterior line, (b) a LA roof line and (c) a mitral isthmus line. Patients continued oral anticoagulation (OAC) therapy or underwent LAAC ≥6 weeks after LAAI. Results Maze-like LAAI was attempted in our center in 107 of 3,611 AF ablation procedures (2.9%) and achieved in 88 of 107 patients (82%). In 8 of 107 (7%) patients cardiac tamponade occurred, all managed conservatively. During follow-up sinus rhythm was established in 65% at 1 year. After LAAI, 45 patients remained on OAC and 40 underwent LAAC. In both groups 1 patient experienced a bleeding complication. Thromboembolism exclusively occurred in the OAC group in 3 (7%) patients. Conclusion LAA isolation by Maze-like substrate modification may be considered a viable option for PVI non-responders. It offers a reproducible approach with an unambiguous procedural endpoint and leads to a favorable clinical outcome. However, extensive LA ablation increased the risk of tamponade. Consecutive LAA occlusion may offer a nonpharmacologic strategy to overcome the high thromboembolic risk associated with absent mechanical LAA contraction. [ABSTRACT FROM AUTHOR]

Aim: A novel third-generation cryoballoon (CB3) to perform pulmonary vein isolation (PVI) has recently been released, featuring a shortened distal balloon tip when compared with the second-generation (CB2), possibly allowing for enhanced intra-ablation pulmonary vein (PV) signal mapping. We aimed to investigate procedural efficacy and safety of the CB3 as compared to the CB2.Methods and Results: We studied 472 consecutive patients who underwent CB-PVI for paroxysmal or persistent atrial fibrillation (CB3: 49 patients; CB2: 423 patients). Detailed procedural data and in-hospital complications were registered in a prospective database. Complete PVI using the CB only was achieved in 98% of patients in each group. Single-freeze PVI was observed in 84/88% (CB2/CB3, P = n.s.) of the PVs. Time-to-PVI (TPVI) was 49 ± 32 (CB2) and 45 ± 27 s (CB3) (P = n.s.). Time-to-PVI determination rate was higher in the CB3 group (89.5 vs. 82.6%, P = 0.016). Signal noise due to ice formation on mapping electrodes occurred after 70 ± 46 s using CB3 and did not interfere with TPVI determination. Exchange of the spiral mapping catheter with a guide wire was more frequently required in the CB3 group (8.2 vs. 0.7% patients, P < 0.001). Balloon dislodgement during hockey stick manoeuvres occurred in 6.1% patients of the CB3 group only (P = 0.001). Complication rates were not different between the groups.Conclusion: The CB3 offers a higher TPVI determination rate, facilitating dosing schemes based on TPVI, with equally high single-freeze efficacy compared with the CB2. The shortened distal tip of the CB3 requires adaptation of standard catheter manoeuvers to avoid balloon dislodgement. [ABSTRACT FROM AUTHOR]

Background Visually guided laserballoon (LB) ablation has recently been introduced for pulmonary vein (PV) isolation (PVI). We analyzed efficacy and safety results of the newly introduced LB ablation technique in patients with persistent and longstanding persistent atrial fibrillation (AF), and compared this with an established standard method using the cryoballoon (CB). Methods A total of 35 patients with symptomatic persistent AF underwent LB ablation and were followed-up for 1 year. Results were compared to 35 patients who underwent CB ablation at the same institution and case matched for age, sex, CHA2DS2-VASc score, and left atrial volume. Results Complete isolation of all PVs was achieved in 68.6% in the LB and 97.1% in the CB group (P < 0.01). No significant differences were found for AF-free survival after 12 months in the complete cohort of all patients (LB: 53.3% vs CB: 70.4%; P = n.s.) and after excluding patients without complete PVI (LB: 57.8% vs CB: 72.5%; P = n.s.). LB ablation resulted in longer procedure (158.5 ± 37.9 minutes vs 110.9 ± 26.5 minutes; P < 0.01) and fluoroscopy durations (28.4 ± 11.1 minutes vs 23.5 ± 9.4 minutes; P = 0.04.), and a trend toward more major complications (14.3% vs 2.9%; P = n.s.). Procedure durations and complications declined over time and were level with CB-treated patients when reaching the last quartile of the LB patients. Conclusion PVI in patients with persistent AF using the LB or the CB resulted in comparable success rates. Initial prolongations in procedure and safety parameters as a result of a learning curve effect for the LB have to be considered before starting to use this technique. [ABSTRACT FROM AUTHOR]

Background: The third-generation Cryoballoon Advance Short-tip (CB-ST) has been designed with a 40 % shortened tip length compared with the former second generation CB advance device (CB-A). Ideally, a shorter tip should permit an improved visualisation of real-time recordings in the pulmonary vein (PV) due to a more proximal positioning of the inner lumen mapping catheter. We sought to compare the incidence of visualisation of real-time recordings in patients having undergone ablation with the CB-ST with patients having received CB-A ablation.Methods: All patients having undergone CB ablation using CB-ST technology and the last 500 consecutive patients having undergone CB-A ablation were analysed. Exclusion criteria were the presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, and contraindications to general anaesthesia.Results: A total of 600 consecutive patients (58.1 ± 12.9 years, 64 % males) were evaluated (100 CB-ST and 500 CB-A ablations). Real-time recordings were significantly more prevalent in the CB-ST population compared with CB-A group (85.7 vs 67.2 %, p < 0.0001). Real-time recordings could be more frequently visualised in the CB-ST group in all types of veins (LSPV 89 vs 73.4 %, p = 0.0005; LIPV 84 vs 65.6 %, p = 0.0002; RSPV 87 vs 67.4 %, p < 0.0001; RIPV 83 vs 62.4 %, p < 0.0001).Conclusion: The rate of visualisation of real-time recordings is significantly higher during third-generation CB-ST ablation if compared to the second-generation CB-A device. Real-time recordings can be visualised in approximately 85.7 % of veins with this novel cryoballoon. [ABSTRACT FROM AUTHOR]

Background Previous studies suggested that cryoballoon ablation had clinical benefits comparable to those of radiofrequency ablation. However, recently, some new catheters have been invented, and no universal consensus exists on which ablation is the optimal choice. The present systematic review and meta-analysis aimed to assess and compare the safety and efficacy of cryoballoon and radiofrequency ablation by synthesizing published trials. Methods and Results A systematic literature review was conducted searching Medline, PubMed, Embase, Cochrane Library, and so forth. All trials comparing cryoballoon and radiofrequency ablation were screened and included if inclusion criteria were met. A total of 40 eligible studies were identified, adding up to 11,395 patients. The follow-up period ranged from 3 months to 25 months. Overall analyses indicated that cryoballoon ablation could bring more benefit in procedural time (risk ratio [RR] = -0.39, 95% confidence interval [CI]: -0.62 to -0.15), atrial fibrillation (AF) recrudescence (RR = 0.82, 95% CI: 0.70-0.96), and major complications (RR = 0.74, 95% CI: 0.58-0.95) for patients with AF. For the subgroups, the first-generation cryoballoon significantly reduced procedural time and major complications, but it increased ablation time. The patients referred for the second-generation cryoballoon (CBA) seemed to receive more clinical benefit (procedural time, fluoroscopic time, ablation time, AF recrudescence) and fewer complications. Finally, multiparty catheter (MTCA) was found to significantly reduce procedural and fluoroscopic times with a high rate of AF recrudescence. Conclusions The present systematic review and meta-analysis demonstrated that cryoballoon ablation was associated with greater freedom from AF, shorter procedural time, and lower rate of major complications, compared with radiofrequency ablation. Especially, CBA was more advantageous. However, MTCA seems promising for radiofrequency ablation. [ABSTRACT FROM AUTHOR]

Aims: The third-generation Cryoballoon Advance Short-tip (CB-ST) has been designed with a 40% shortened tip length compared with the former second-generation CB Advance device. Ideally, a shorter tip should permit an improved visualization of real-time (RT) recordings in the pulmonary vein (PV) due to a more proximal positioning of the inner lumen mapping catheter. In the present study, we sought to analyse the rate of visualization of RT recordings in our first series of patients with the CB-ST device.Methods and Results: All consecutive patients having undergone CB ablation using CB-ST technology were analysed. Exclusion criteria were the presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, and contraindications to general anaesthesia. A total of 60 consecutive patients (60.5 ± 11.2 years, 62% males) were evaluated. Real-time recordings were detected in 209 of 240 PVs (87.1%). Specifically, RT recordings could be visualized in 55 left superior PVs (91.7%), 51 left inferior PVs (85.0%), 53 right superior PVs (88.3%), and 50 right inferior PVs (83.3).Conclusion: The rate of visualization of RT recordings is significantly high during third-generation CB-ST ablation. Real-time recordings can be visualized in ∼87.1% of veins with this novel cryoballoon. [ABSTRACT FROM AUTHOR]

Significant Delayed ET Drop After CB-Based PV Vein Isolation Background The second-generation cryoballoon (CB2) has demonstrated superior clinical outcome. Potential procedural complications include esophageal thermal lesions due to excessive esophageal temperature (ET). Safety cut-offs for the ET have previously been published. A safety margin was incorporated due to a delayed esophageal temperature decline even after termination of the CB2 freeze cycle. The extent of these delayed temperature drops requires further systematic evaluation. Methods and Results The study enrolled 29 patients with paroxysmal or shortstanding persistent AF who underwent CB2-based PVI. Freeze cycle duration was 240 seconds. No bonus freeze was applied after successful PVI. The intraluminal ET was continuously measured via a transorally inserted probe (SensiTherm, St. Jude Medical, Inc.). The CB2 temperature and ET were recorded throughout the procedure using a camera setup. The mean number of freeze cycles per patient was 4.3 ± 2. A total of 147 cryoenergy applications were analyzed. A delayed decline in ET of >0.5 °C was recorded following termination of 23.1% of freeze cycles. The maximum drop in delayed ET was 6.4 °C. Excessive esophageal cooling during the freeze cycle exceeding 8.5 °C/min may result in ET ≤10 °C. Conclusions Following termination of cryoenergy delivery, the ET may decline an additional 6.4 °C. Proposed ET safety cut-offs during CB2-based PVI need to account for a significant ET drop that may occur even after termination of the individual freeze cycle. [ABSTRACT FROM AUTHOR]

Aim: The second-generation cryoballoon (CB-Adv) is effective in achieving pulmonary vein isolation (PVI) with encouraging results. In this study, we assessed the single-procedure outcome on a 1-year follow-up period in a large sample of patients having undergone PVI for drug-resistant atrial fibrillation (AF) using the CB-Adv.Methods and Results: A total of 393 patients (122 female, 31%; mean age 57.7 ± 12.9 years) with drug-refractory AF undergoing PVI using the novel CB-Adv were enrolled. Follow-up was based on outpatient clinic visits including Holter electrocardiograms. Recurrence of atrial tachyarrhythmias (ATas) was defined as a symptomatic or documented episode >30 s. A total of 1572 pulmonary veins (PVs) were identified and successfully isolated with 1.2 ± 0.3 mean freezes. Mean procedure and fluoroscopy times were 87.1 ± 38.2 and 14.9 ± 6.1 min, respectively. At a mean follow-up of 12 months, freedom from ATas after a single procedure was achieved in 85.8% of patients with paroxysmal atrial fibrillation and in 61.3% of patients with persistent AF (persAF). Similar success rates were observed between bonus freeze and single freeze strategies, 82.5 and 81.8%, respectively (P = 0.9). Multivariate analysis demonstrated that persAF (P = 0.04) and relapses during blanking period (BP) (P < 0.0001) were independent predictors of ATas recurrences.Conclusion: Freedom from any ATa can be achieved in 81.9% of patients after a single CB-Adv procedure in a large cohort of patients. A bonus freeze does not influence the clinical outcome, and reducing the duration of the cryoapplication to 3 min offers excellent results. Persistent AF and arrhythmia recurrence during the BP are strong predictors of AF recurrence. [ABSTRACT FROM AUTHOR]

Second-Generation Cryoballoon Ablation Background Lone atrial fibrillation (LAF) develops in younger individuals without cardiovascular or pulmonary disease. As pulmonary vein isolation has been recognized as an optimal treatment for drug-resistant atrial fibrillation, cryoballoon ablation with second-generation balloon (CB-A) may be an ideal solution for LAF patients. Objective The aim of this study was to investigate acute success, periprocedural complications and outcome over a 12-month follow-up period in a cohort of patients having undergone PV isolation (PVI) for LAF using CB-A technology. Methods A total of 75 consecutive patients (50 male, mean age 47 ± 12 years) with a diagnosis of lone paroxysmal atrial fibrillation who underwent pulmonary vein isolation (PVI) by CB-A from June 2012 were included. All patients underwent this procedure with the 28 mm CB-A. A total of 299 PVs (100%) could be isolated with CB-A alone. Results The freedom from AF recurrence after a single procedure was 92% of patients during the entire 13-month follow-up. When considering a blanking period (BP) of 3 months, success rate was 93.3%. Transient phrenic nerve palsy (PNP) was the most frequent complication, occurring in 5.3% of individuals (4 patients); complete recovery was documented for all of these patients prior to hospital discharge. Conclusions CB-A is extremely effective in achieving PVI and affords freedom from AF at 13-month follow-up in 93% of young patients affected by drug-resistant LPAF following a 3-month BP. The most frequent complication observed was PNP, which reverted prior to discharge in all patients. [ABSTRACT FROM AUTHOR]

Background Second-generation cryoballoon (CB-2) is associated with improved outcomes for pulmonary vein isolation (PVI) compared to first generation (CB-1). However, data regarding the predictors of pulmonary vein (PV) electrical reconnection are limited. In this study, we aimed to characterize the predilection sites and predictors of reconnection in patients with recurrent atrial tachyarrhythmia (ATa) after PVI using CB-1 and CB-2. Methods A total of 59 patients (mean age: 62 ± 11 years and 66% male) with recurrent ATa after previous CB-PVI, using either a 28-mm CB-1 or CB-2, underwent repeat ablation. PV reisolation was performed by irrigated radiofrequency ablation using three-dimensional electroanatomical mapping systems. Results Electrical PV reconnection was detected in 10 of 11 (91%) of CB-1 patients compared to 41 of 48 (85%) of CB-2 patients. Time to redo procedure after index CB-1 was 8.9 ± 10.2 months and 11.2 ± 7.0 months in CB-2. Bonus freeze was applied in all patients with CB-1 and 41% of the patients with CB-2. Superior quadrants of both superior PVs and inferior quadrants of the both inferior PVs exhibited higher predilection for conduction compared to other quadrants (P < 0.001). Multivariate binary logistic analysis revealed that right inferior PV (RIPV; odds ratio [OR]: 1.52, 95% confidence interval [CI]: 1.09-2.13, P = 0.014) and minimum temperature (OR: 1.09, 95% CI: 1.03-1.15, P = 0.004) were the independent predictors of electrical reconnection after CB-2 ablation. Conclusion Conduction gaps after CB-1 and CB-2 were higher in inferior PVs compared to superior PVs. The RIPV and minimum CB temperature were independent predictors of PV electrical reconnection after CB-2. [ABSTRACT FROM AUTHOR]

Aims: The role of balloon catheters in patients with persistent forms of atrial fibrillation (AF) remains ill defined. We therefore sought to assess the safety and efficacy of a laser balloon (LB)-guided pulmonary vein isolation (PVI) in consecutive all-comers with persistent AF.Methods and Results: All patients undergoing an LB-guided PVI procedure for persistent AF between January 2011 and December 2012 were matched to patients undergoing circumferential PVI using irrigated radiofrequency (RF) current ablation for date of procedure, age, gender, AF duration, left atrial (LA) size, and left ventricular ejection fraction. The primary endpoint was freedom from AF between 90 and 365 days post-ablation after a single procedure. Eighty patients (mean age 66 ± 9; 71% male) with a median (Q1-Q3) AF episode duration of 2 (1-3) months underwent successful PVI in the two groups. The primary endpoint of 1-year single procedure AF/atrial tachycardia (AT) recurrences was reached by 11/40 (27.5%) patients in the LB group and in 9/40 (22.5%) patients in the RF group (P = 0.87). During a mean follow-up of 517 ± 170 days, 13 (32.5%) and 16 (40%) patients in the LB and RF groups, respectively, experienced AF/AT recurrences (P = 0.64). Procedural complications occurred in one patient in the LB group and in six patients in the RF group.Conclusion: A subset of patients with drug-refractory persistent AF of short duration benefit from pure PVI without additional substrate modification. A LB-based strategy showed similar outcomes as an irrigated RF-guided circumferential PVI and may be considered an alternative option for the index ablation. [ABSTRACT FROM AUTHOR]

Aims: Complications such as thermal oesophageal lesions, phrenic nerve injury, and pulmonary haemorrhage were found in cryoballoon (CB) ablation. Whether shortening of freezing times translates into equal efficacy rate and outcome is unknown. The aim of this study was to test the hypothesis that a single freeze cycle per pulmonary vein (PV) without dormant conduction during adenosine infusion is equally effective to standard CB procedure with a bonus freeze after documented PV isolation (PVI).Methods and Results: In 53 patients with drug-refractory atrial fibrillation (AF) demonstrating PVI after a single 240 s freeze cycle without PV activity during adenosine no additional bonus freeze was applied (study group). In 139 patients, PVI was performed using a bonus freeze (240 s) after documented PVI (control group). Primary endpoint was recurrence of AF. Secondary endpoint was the assessment of quality of life (QoL-score from 1 to 6, being 1 the best and 6 the worst). Follow-up (FU) was performed at 3, 6, and 12 months. Freedom from symptomatic AF during a mean FU of 458 ± 107 days was achieved in 43 (81%) patients in the study group and in 110 (79%) control patients (P = ns). The QoL-score improved equally in both groups (4.8 ± 0.9 to 2.1 ± 0.7, P < 0.05 and 4.7 ± 0.6 to 2.2 ± 0.6, P < 0.05). Procedure duration (79 ± 14 vs. 98 ± 16 min, P < 0.01) was shorter in the study group. Complication rate was similar in both groups.Conclusion: Shortening of freezing times to 4 min per PV without residual dormant PV conduction after adenosine provocation is equally effective to the standard CB ablation protocol using a bonus freeze. [ABSTRACT FROM AUTHOR]

Aims: Irrigated multi-electrode ablation (IMEA) is a novel tool to perform pulmonary vein isolation (PVI). The aim was to compare IMEA with point-by-point radiofrequency (RF) ablation in patients with persistent atrial fibrillation (AF) undergoing PVI.Methods and Results: Forty-nine patients (age 60 ± 9 years, 82% male) were studied. In 24 patients, the IMEA catheter was used in conjunction with an electroanatomic mapping system. Twenty-five patients undergoing RF point-by-point ablation (RF-PVI) served as a control group. Validation of PVI based on the IMEA catheter was performed using a standard circular mapping catheter. Ninety-two of 94 pulmonary veins (PVs) (98%) were isolated using IMEA alone. Procedure time was 125 ± 23 min in the IMEA group and 127 ± 31 min in the RF-PVI group (P = 0.79). Fluoroscopy time was 12.2 (11-16.1) min with IMEA compared with 5.2 (4.1-9.3) min in the RF-PVI group (P < 0.001). Net ablation time was 11.8 (10.2-15.4) min in the IMEA group compared with 33.6 (30.3-40.1) min in the RF-PVI group (P < 0.001). Of 94 PVs presumed to be isolated after IMEA ablation, validation using a standard circular mapping catheter showed persistent PV potentials in 33 PVs (35%), requiring additional IMEA ablation. At 12 months, 16 of 24 patients (67%) in the IMEA group compared with 17 of 25 patients (68%) in RF-PVI group were free from AF (P > 0.99).Conclusion: With similar total procedure duration, IMEA-PVI was associated with shorter net ablation time and longer fluoroscopy time. Irrigated multi-electrode ablation recordings were not sufficient to confirm isolation in 35% of PVs. Single-procedure efficacy after 12 months was similar between the two groups. [ABSTRACT FROM AUTHOR]

Aims: To assess the incidence of late pulmonary vein (PV) reconnection following index PV isolation (PVI) procedure initially achieved with radiofrequency contact-force catheter ablation (CFCA) and second-generation cryoballoon ablation (CB-AdvA).Methods and Results: A total of 56 consecutive patients (41 male, 73.2%; mean age 60.8 ± 11.8 years) underwent a repeat ablation because of recurrent atrial tachyarrhythmias (ATas) after index PVI achieved with CFCA (30 patients) or CB-AdvA (26 patients). All repeat procedures were performed by the means of CFCA. In the CFCA group, among 119 PVs, 43 (36.1%) showed conduction gaps in 24 patients (1.8 per patient), whereas in the CB-AdvA group among 103 veins, 21 (20.4%) showed a PV reconnection in 18 patients (1.2 per patient) (P = 0.01). The left superior pulmonary vein was less frequently reconnected following CB-AdvA when compared with CFCA (2/25, 8% vs. 11/29, 37.9%; P = 0.01). In the CFCA group, the mean CF per-vein was lower in reconnecting veins when compared with those persistently isolated (10.9 ± 2.7 vs. 18.6 ± 3.1 g; P < 0.001). In the CB-AdvA group, late PV reconnection was associated with warmer nadir temperature (-48.9 ± 5.1 vs. -51.2 ± 4.7°C; P = 0.05) and longer time-to-isolation (71.1 ± 20.2 vs. 50.2 ± 32.9 s; P = 0.03).Conclusion: The rate of late PV reconnection is significantly lower following CB-AdvA when compared with CFCA as index procedure. Lower CF values and warmer nadir temperature with longer time to effect were more frequently associated with PV reconnections in the setting of CFCA and CB-AdvA. [ABSTRACT FROM AUTHOR]

Visually Guided PV Isolation Introduction Visually guided laser balloon (VGLB) ablation is unique in that the operator delivers ablative energy under direct visual guidance. In this multicenter study, we sought to determine the feasibility, efficacy, and safety of performing pulmonary vein isolation (PVI) using this VGLB. Methods Patients with symptomatic, drug-refractory paroxysmal atrial fibrillation (AF) underwent PVI using the VGLB with the majority of operators conducting their first-ever clinical VGLB cases. The primary effectiveness endpoint was defined as freedom from treatment failure that included: Occurrence of symptomatic AF episodes ≥1 minutes beyond the 90-day blanking, the inability to isolate 1 superior and 2 total PVs, occurrence of left atrial flutter or atrial tachycardia, or left atrial ablation/surgery during follow-up. Results A total of 86 patients (mean age 56 ± 10 years, 67% male) were treated with the VGLB at 10 US centers. Mean fluoroscopy, ablation, and procedure times were 39.8 ± 24.3 minutes, 205.2 ± 61.7 minutes, and 253.5 ± 71.3 minutes, respectively. Acute PVI was achieved in 314/323 (97.2%) of targeted PVs. Of 84 patients completing follow-up, the primary effectiveness endpoint was achieved in 50 (60%) patients. Freedom from symptomatic or asymptomatic AF was 61%. The primary adverse event rate was 16.3% (8.1% pericarditis, phrenic nerve injury 5.8%, and cardiac tamponade 3.5%). There were no cerebrovascular events, atrioesophageal fistulas, or significant PV stenosis. Conclusions This multicenter study of operators in the early stage of the learning curve demonstrates that PVI can be achieved with the VGLB with a reasonable safety profile and an efficacy similar to radiofrequency ablation. [ABSTRACT FROM AUTHOR]

Cryoenergy Interruption Due to Phrenic Nerve Palsy Introduction Right phrenic nerve paralysis (PNP) is the most frequently observed complication occurring during cryoballoon ablation (CB). Our aim was to analyze the impact of the premature interruption (PI) of cryoenergy delivery in a large series of consecutive patients during ablation in the right-sided veins on clinical outcome. Methods and Results All consecutive patients having undergone second-generation CB ablation for paroxysmal atrial fibrillation (AF) from July 2012 to September 2014 were included in our analysis. Exclusion criteria were persistent AF, presence of an intracavitary thrombus, uncontrolled heart failure, moderate or severe valvular disease, left atrium (LA) diameter ≥55 mm, and contraindications to general anesthesia. A total 287 consecutive patients with drug-resistant paroxysmal AF having undergone pulmonary vein isolation by means of CB technology (male 65%, age 57.6 ± 13.1 years) were included. The incidence of PNP in the study population was 8.0% (23/287). At a mean follow-up of 11.5 ± 3.9 months, the success rate without antiarrhythmic therapy was 81.6%. Patients with PNP had similar rates of AF recurrence compared with those without PNP (17.4% vs. 17.8%; P = 0.9); the former had a mean follow-up of 10.9 ± 3.7 months, the latter 11.8 ± 4.5 months (P = 0.3). Conclusion Conclusion: Our findings show that patients in whom freezing was interrupted due to PNP had a similar outcome on 1-year follow-up compared with those in whom freezing cycles were completed in the septal veins. No baseline clinical or procedural characteristics were found to predict AF recurrence in patients having experienced PNP. [ABSTRACT FROM AUTHOR]

Aims In this observational study, we examine the significance of the left atrial (LA) surface area and compare the clinical usage of the Arctic Front Advance (CBA) versus Arctic Front (CB) cryoballoon with the intent to investigate the impact of each in terms of long-term freedom from atrial fibrillation (AF) for patients with nonvalvular AF. Methods Pulmonary vein isolation (PVI) was performed while using a cryoballoon ablation catheter in conjunction with an intraluminal circular diagnostic mapping catheter, Achieve. The consecutive patients ablated with CBA were matched with patients previously ablated with CB, using propensity score matching. The primary endpoint of this observational single-center retrospective study was the first observation of electrocardiogram-documented recurrence of atrial arrhythmias lasting >30 seconds. Results The patient demographic data were similar in the CBA- and CB-group (N = 188 patients each group). In all patients in the CBA-group and in 95% of the patients in the CB group, acute procedural PVI of all veins was achieved with the single usage of a 28-mm cryoballoon. The one-year freedom from atrial arrhythmias was significantly better in the CBA- versus the CB-group of patients, 90% versus 64%, respectively. During 15-month clinical follow-up in CBA group, patients with LA area above 23 cm2 were more likely to experience recurrence of AF (23%) than patients with LA area below 23 cm2 (7%). Conclusions Comparing one-year outcomes, the CBA is superior to the CB with regards to maintenance of normal sinus rhythm. When using the CBA catheter, an enlarged LA is associated with a higher recurrence of arrhythmia. [ABSTRACT FROM AUTHOR]

Aims: Adenosine administration after pulmonary vein (PV) isolation using radiofrequency, laser, and cryoablation can cause acute recovery of conduction to the PVs and predict atrial fibrillation (AF) recurrence. This study evaluates whether ablation of dormant potentials post-adenosine administration following second-generation cryoballoon (CB-2G) ablation may improve the success rate for AF. Methods and results: In 45 of 90 patients after a waiting period of 30 min, a bolus 15-21 mg of adenosine was administered followed by rapid saline flush. The response was assessed for each PV using a circular octapolar catheter. If needed, further ablation using a cryoballoon and/or cryocatheter was performed until no reconduction was observed after repeat adenosine administration. The remaining 45 patients did not receive adenosine after the procedure. Acute PV isolation was achieved in 352 of 358 PVs (98.3%) of 86 of 90 patients (95.6%) using CB-2G. The adenosine group showed dormant reconduction in 5 of 45 patients (11%), 8 of 179 PVs (4.5%), including 1 left superior pulmonary vein, 3 left inferior pulmonary vein, 1 right superior pulmonary vein, and 3 right inferior pulmonary vein. The success rate for adenosine and without adenosine group was 84 and 79%, respectively, after a mean follow-up of 397 ± 47 and 349 ± 66 days, without any AF recurrence in patients in whom adenosine-induced dormant conduction was ablated. Conclusion: Adenosine testing after second-generation cryoballoon ablation study showed that reablation of initially isolated PVs increases the clinical success rate for AF. [ABSTRACT FROM AUTHOR]

Durability of Pulmonary Vein Isolation with Cryoballoon Ablation Introduction Pulmonary vein (PV) reconnection remains the most important cause of AF recurrence after AF ablation. The second-generation cryoballoon catheter's ability to achieve durable PV isolation was assessed in a prospective nonrandomized clinical trial. Methods and Results PV isolation was performed by 4-minute ablations. Following verification of electrical isolation by a multielectrode mapping catheter, 1 additional lesion per PV was applied. Esophageal temperatures were monitored and all patients underwent postprocedure esophageal endoscopy. All patients underwent a second PV remapping procedure at ∼3 months to assess for PVI durability. Eighty-four (100%) veins were acutely isolated using only the 28 mm cryoballoon in 21 consecutive PAF patients with 2.2 ± 0.6 cryoapplications per vein, with the majority (83%) occurring after a single freeze. One patient presented with hematemesis and an esophageal ulceration that was treated conservatively; there were no episodes of esophageal fistula or phrenic nerve palsy. At 3.4 (2.9-4.1) months postablation, 68/75 veins (91%) remained electrically isolated; all PVs remained durably isolated in 79% of patients. Two patients accounted for 5 of 7 reconducting veins. The most common site for reconnection was the inferior aspect of the RIPV (3/7 reconnections). Reconnected veins had poorer occlusion at the index ablation procedure than veins that maintained chronic isolation (occlusion grade 2.9 ± 0.7 vs. 3.4 ± 0.7, P = 0.001). Clinical AF recurrence was detected in 2 patients (11%) at follow-up. Conclusions The improved thermodynamic characteristics of the second-generation cryoballoon led to a high rate of both single-shot PVI and chronic lesion durability. This high rate of durable PV isolation is anticipated to translate to improved clinical outcome. [ABSTRACT FROM AUTHOR]

Aims: To compare ablation lesion formation after pulmonary vein isolation (PVI) using the standard cryoballoon (CB-S) vs. the re-designed cryoballoon Arctic Front Advance (CB-A) using late gadolinium enhancement magnetic resonance imaging (LGE-MRI) 3 months post-ablation. Methods and results: Thirty-six consecutive patients with paroxysmal or short-lasting persistent atrial fibrillation (AF) were evaluated prospectively after PVI using the CB-S in the first 18 patients and the CB-A in the subsequent 18 patients. All patients underwent LGE-MRI and a 7-day Holter electrocardiogram monitoring 3 months after ablation. Fifty-six per cent of the patients were male (mean age 63.0 ± 9.1 years). Fifty-six percent in the first group and 89% in the second group were free of AF recurrence 3 months after ablation (P = 0.025). Three months after ablation, LGE-MRI of the left atrium showed complete circular lesions in 35% of PVs in the first group and in 32% of PVs in the second group (n.s.). The left PVs showed a significantly higher proportion of PV segments with complete ablation lesions compared with the right PVs (83 vs. 34%; P < 0.001). Conclusion: Cardiac MRI is able to visualize induced ablation lesions after PVI and might be suitable to quantify ablation lesion amount. Ablation lesion formation did not differ significantly in patients treated with the CB-S vs. the CB-A, despite a significantly lower rate of AF recurrence after 3 months in the CB-A group. Left PVs showed a significantly higher amount of ablation lesions compared with the right PVs. Larger and randomized studies are needed to understand the relationship between representable tissue lesions and success rates. [ABSTRACT FROM AUTHOR]

Aims In the setting of paroxysmal atrial fibrillation (AF), there are no available data comparing the mid-term outcome of patients undergoing pulmonary vein isolation (PVI) catheter ablation using contact-force (CF)-guided radiofrequency (RF) vs. second-generation balloon cryotherapy. Methods and results Prospective single-centre evaluation, carried out from March 2011 to February 2013, comparing CF radiofrequency (Thermocool® SmartTouch™, Biosense Webster, Inc.) (CF group) with cryoballoon ablation (Arctic Front Advance™ 28 mm cryoballoon, Medtronic, Inc.) (CB group), in regards to procedural safety and efficacy, as well as recurrence at 12 months. Overall, 150 consecutive patients were enrolled (75 in each group). The characteristics of patients of both the groups were similar (61.2 ± 9.9 years, women 25.3%, mean AF duration 4.1 ± 4.0 years, mean CHA2DS2-VASc score 1.4 ± 1.3, mean HAS-BLED 1.4 ± 0.6). Duration of the procedure was significantly lower in the CF group (110.7 ± 32.5 vs. 134.5 ± 48.3 min, P = 0.001), with a lower duration of fluoroscopy (21.5 ± 8.5 vs. 25.3 ± 9.9 min, P = 0.017) and X-ray exposure (4748 ± 2411 cGy cm² vs. 7734 ± 5361 cGy cm², P = 0.001). In contrast, no significant difference was found regarding significant procedural complication (2.7 vs. 1.3% in CF and CB groups, respectively; P = 0.56), and PVI was eventually achieved in all cases. At 12 months, AF recurrence occurred in 11 patients (14.7%) in the CB group and in 9 patients (12.0%) in the CF group (HR = 1.20 95% CI 0.50–2.90; log rank P = 0.682). Conclusions Our preliminary findings suggest that CF-guided radiofrequency and cryotherapy present very similar performances in the setting of paroxysmal AF catheter ablation. [ABSTRACT FROM PUBLISHER]

Background We investigated whether the new second generation of cryoballoons can improve the efficiency and safety of cryoablation for atrial fibrillation (AF) during ablation and in terms of outcome. Methods Data of AF patients consecutively treated with a single 28-mm cryoballoon were analyzed. Patients were divided into two groups: the G1 group was treated with the first-generation cryoballoons (ArcticFront) and G2 with the second generation (ArcticFront Advance). Failure of cryoablation treatment was defined as detection of an episode of AF, atrial flutter, or atrial tachycardia lasting ≥30 seconds during 3-month follow-up. Left atrial diameter (LAD) was measured by transthoracic echocardiography before cryoablation. Results One hundred twenty-five patients (group G1/G2: 57/68) were enrolled. Mean total time of the whole procedure, cryomapping, and cryoablation was shorter with G2 than with G1 (P < 0.05). No complication occurred with G1 whereas with G2 the complication rate was 8.8%. During mean 12 ± 4 months follow-up, the overall success rate of cryoablation was 76.0% (95/125); it was higher with G2 (89.7% [61/68] vs 59.7% [34/57], P < 0.001). Patients in whom treatment failed had larger LAD (48 ± 8 mm vs 44 ± 6 mm, P = 0.002) than those in whom it succeeded. Type of cryoballoon (relative risk [RR] = 5.75 [2.16, 15.27], P < 0.0001) and LAD (RR = 0.90 [0.83, 0.97], P = 0.0043) were shown in multivariable analysis to be individually related to the difference in success rate. Conclusion Ablation for AF with the new generation of cryoballoons is associated with higher success rate of pulmonary vein isolation and better outcome. However, more complications occurred during the early stage of application of the G2 cryoballoon. [ABSTRACT FROM AUTHOR]

Introduction: Novel ablation devices for pulmonary vein isolation (PVI) need a careful evaluation of its efficacy and safety beyond clinical studies in a real world situation. The endoscopic ablation system (EAS) was recently approved for PVI in Europe. We sought to determine the safety, efficacy, and learning curve effects of EAS-PVI in a large volume single center. Methods and Results: Between June 2010 and March 2013, all EAS guided PVI procedures were analyzed and 150 consecutive patients were divided in tertiles (T). Clinical follow-up of 12 months assessed freedom from atrial fibrillation (AF) using 72 hour-Holter ECG recordings. In total, 497 of 583 PVs (85%) were isolated by visual guidance only. In T 2 and T 3, visually guided PVI rates increased from 73% to 91% (P < 0.001). After gap mapping, 96% and 99% of all PVs were isolated in T 1-3, respectively (P = 0.018). Total procedure and fluoroscopy time significantly declined over time. All major periprocedural complications occurred in the first T. In 3 patients (2 in 1st and 1 in 2nd T), phrenic nerve palsy was observed (2%). At 12-months follow-up, 103 of 133 patients (77%) remained in stable sinus rhythm without significant differences between Ts. Conclusion: With EAS even first time users may achieve acute PVI in a high number of patients with favorable clinical outcomes after 1 year. Yet, acute procedural efficacy and safety are further improved after passing a learning curve of 50 patients. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia imposing substantial morbidity and mortality. Catheter-based pulmonary vein isolation (PVI) using radiofrequency current (RFC) has become a standard treatment for drug-resistant and symptomatic paroxysmal AF (PAF). In recent years, the cryoballoon-based technique is increasingly used as a promising alternative with a short learning curve. Methods: The FIRE AND ICE trial is a prospective, randomized, controlled, open, blinded outcome assessment, noninferiority trial comparing cryoballoon-, and RFC-based PVI. Patients with drug-resistant PAF will be randomized in a 1:1 matrix in multiple European centers. The primary hypothesis is that cryoballoon ablation is not inferior to RFC ablation using 3-dimensional mapping with respect to clinical efficacy. The primary endpoint is defined as the time to first documented clinical failure, including: (1) recurrence of AF; (2) atrial flutter or atrial tachycardia; (3) prescription of class I or III antiarrhythmic drugs; or (4) re-ablation, whichever comes first, following a blanking period of 3 months after the index ablation procedure. The primary safety endpoint is a composite of death, stroke/transient ischemic attack, cardiac arrhythmias (apart from AF recurrence) causally related to the therapeutic intervention, and procedure-related serious adverse events. Conclusion: The FIRE AND ICE trial compares 2 different technologies to perform catheter ablation of PAF with respect to efficacy and safety. It aims at providing objective data to guide selection and usage of ablation catheters in the treatment of AF. [ABSTRACT FROM AUTHOR]

Aims: Adenosine administration after pulmonary vein (PV) isolation using radiofrequency and cryoablation can cause acute recovery of conduction to the PVs and predicts atrial fibrillation (AF) recurrence. This study evaluated whether adenosine testing after second-generation balloon devices (cryothermal and laser) could reveal dormant PV reconduction and recurrence rate of AF. Methods: Out of total 60 patients, 20 patients underwent PV isolation using laser balloon and for the remaining patients, the cryoballoon was used. Following PVI, waiting period of 30 min was obtained. Thereafter, a bolus 15-21 mg of adenosine was injected followed by rapid saline flush. The subsequent response was assessed for each vein using an in situ lasso catheter. Further ablation (if needed) using laser balloon and cryocatheter respectively was done, until no reconduction occurred after repeat adenosine. Results: Acute PV isolation was achieved in all 80 PVs of 20 patients (100 %) using laser device and in 151 PVs (96.2 %) of 38 patients (95 %) using cryoballoon. However, in seven patients (35 %), 11 PVs (13.7 %) (4 LSPV, 2 LIPV, 4 RSPV, and 1 RIPV) showed dormant PV potentials after adenosine administration in laser group. Cryoballoon group showed dormant reconduction in four patients (10 %), four PVs (5 %) [one LSPV, one LIPV, and two RIPV]. The follow-up of 337 ± 92.4 days for cryoballoon and 267 ± 76.9 days for laser balloon group demonstrated similar success rates (85 %). Conclusion: Adenosine testing after PV isolation using second-generation balloon based energy devices (laser and cryothermal) reveals dormant conduction in initially isolated PVs with similar long-term success rate. [ABSTRACT FROM AUTHOR]