First Dutch experience with the endoscopic laser balloon ablation system for the treatment of atrial fibrillation
The endoscopic laser balloon ablation system (EAS) is a relatively novel technique to perform pulmonary vein isolation (PVI) in the treatment of atrial fibrillation (AF). The present study aimed to report the results of the first 50 patients treated in the Netherlands with the EAS in terms of procedural characteristics and AF-free survival.
Fifty patients successfully underwent EAS PVI. Median follow-up was 17 months. Mean age was 56 years, 82 % had paroxysmal AF.
99 % of the pulmonary veins were successfully isolated with the EAS. Mean procedure time was 171 min and mean fluoroscopy time was 36 min. One procedure was complicated by a temporary phrenic nerve palsy (2 %). During follow-up, 58 % of patients remained free of AF without the use of antiarrhythmic drugs.
PVI with EAS is associated with a low risk of complications and a medium-term AF-free survival comparable with other PVI techniques.
KeywordsAtrial fibrillation Ablation Pulmonary vein isolation Laser balloon ablation
Pulmonary vein isolation (PVI) has become an important treatment modality for atrial fibrillation (AF) [1, 2] although AF recurrences can occur . Several PVI techniques have been developed [4, 5] in an attempt to increase AF-free survival, among which the endoscopic laser balloon ablation system (EAS) [6, 7]. The EAS consists of a flexible, compliant balloon for sustained wall contact and an adjustable laser beam for ablation independent of tissue contact. The present study aims to report the procedural characteristics and AF-free survival after EAS PVI of the first 50 patients treated with the EAS in the Netherlands.
Fifty consecutive patients who underwent a primo PVI using the EAS in our centre between December 2011 and December 2013 were included in a prospective registry. The prospective registry has been approved by the Institutional Review Board and all patients consented to their data being registered.
All patients underwent transoesophageal echocardiography to rule out left atrial (LA) thrombus prior to the procedure. Patients stopped using anticoagulants and were ‘bridged’ with low-molecular-weight heparin until the day of ablation, in accordance with local guidelines.
The endoscopic laser balloon
Patients visited the outpatient clinic at 3, 6, 12, 18 and 24 months after PVI, including 24-h Holter ECG. AF recurrence was defined in accordance with European guidelines . In all patients, antiarrhythmic drugs were ceased 3 months after the PVI.
The primary endpoint of our study was AF-free survival after EAS PVI. Secondary endpoints were: acute PVI, procedure time, ablation time and fluoroscopy time. The safety endpoint was major or minor complications within 30 days of the procedure as described in European guidelines .
Continuous variables were expressed as mean with standard deviation in case of normal distribution or median with interquartile range when not normally distributed. Statistical analysis was performed using IBM SPSS statistics version 20 (IBM inc., Armonk, NY, USA).
Total (n = 50)
Gender female (%)
AF duration (years)
Failed AADs (range)
LA ventral-dorsal dimension (mm)
History of hypertension
History of diabetes mellitus
Procedure time (min)
Ablation time (min)
Fluoroscopy time (min)
After a median follow-up of 17.3 (interquartile range: 12.9–19.5) months, 58 % of patients were free of AF after a single EAS PVI without the use of antiarrhythmic drugs.
The present study reports the results of the first 50 patients treated with the EAS in the Netherlands. Acute PVI can be achieved virtually always, with a low risk of complications. Moreover, medium-term AF-free survival seems to be comparable with other PVI techniques.
The EAS combines a compliant balloon design, an endoscope for visualisation of PV antral tissue and a power-adjustable laser beam. Previous reports have shown that acute PVI can be achieved virtually always with the EAS, which was also observed in the present study [8, 9]. In the present study, the complication rate is low (2 %), which is consistent with previous reports [7, 9].
Although PVI is an important treatment modality for AF, the medium-term AF-free survival is still 60–80 %, after PVI using different techniques, such as radiofrequency catheter ablation  and cryoballoon ablation . In the present study, AF-free survival after a single EAS PVI attempt was 58 %, which is in line with a previous report , although there are other EAS studies reporting a higher AF-free survival [10, 11]. Potentially, a learning curve may, in part, have affected the AF-free survival in the current study. A randomised trial will provide further evidence of the AF-free survival after EAS . Based on the current literature, the AF-free survival rate after EAS PVI seems to be comparable with other techniques.
AF recurrences are generally regarded as recurrence of electrical conduction over the PV-LA junction [13, 14]. Durable lesion sets therefore remain pivotal in improving medium-term AF-free survival after PVI. The medium-term success percentage suggests the lesion sets created with the EAS are not persistent. This was also suggested in another study , which reported that 62 % of the studies patients had 4 isolated PVs 3 months after the initial EAS PVI procedure.
Future studies should be aimed at identifying factors that are associated with AF-free survival after EAS PVI. Although the EAS consists of a compliant balloon, the catheter-tissue contact may be suboptimal in some patients, limiting the operator’s ability to deliver circular, transmural lesion sets which may influence AF-free survival. Moreover, in case of insufficient occlusion or ablation near to a blood pool, ablation energy had to be reduced. One study  showed high-energy EAS ablation was favourable to low-energy EAS ablation in terms of persistent electrical conduction over the PV-LA junction and AF-free survival after PVI. Although highly speculative, these factors may explain the medium-term AF-free survival in the present study.
The EAS is a promising technique with a high acute PVI success rate and a low risk of complications. Medium-term AF-free survival after EAS PVI is comparable with other PVI techniques.
Conflict of interest
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- 1.Calkins H, Kuck KH, Cappato R, et al. HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design. Europace. 2012;14:528–606.PubMedCrossRefGoogle Scholar
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