Impact of pulmonary vein anatomy assessed by cardiac magnetic resonance imaging on endoscopic pulmonary vein isolation in consecutive patients.

AIMS: Recently, the novel endoscopic ablation system (EAS) was introduced and proved its potential for successful pulmonary vein isolation (PVI) in patients suffering from paroxysmal atrial fibrillation (PAF). The current study will investigate the impact of pulmonary vein (PV) anatomy assessed by pre-interventional cardiac magnetic resonance imaging (CMRI) on endoscopic PVI. METHODS AND RESULTS: Fifty-one patients (23 females, age 57 ± 9 years) with a long history (5 ± 5 years) of drug-refractory PAF were included into our analysis. Cardiac magnetic resonance imaging was performed in all patients before ablation. Each CMRI was evaluated for the number of PVs, for separate or common insertion of ipsilateral PVs, for the PV diameter and PV shape (round vs. oval), for the level of first PV branching, and for the level of insertion of the right inferior PV (RIPV) into the left atrium (LA), respectively. Pulmonary vein isolation was performed using exclusively the novel EAS. The CMRI findings were correlated with the ablation results. A total of 195 PVs were identified and targeted. In 192 of 195 (98%) PVs successful isolation was achieved using the novel EAS irrespective of the PV diameter, the PV shape, the level of PV branching, or the type of insertion of the PV into the LA. There was no statistical significance when correlating the CMRI findings with acute isolation success of the respective PVs or the number of laser applications needed until PVI (P> 0.05). A low level of insertion of the RIPV into the LA was not associated with PVI failure or a higher number of laser applications (P> 0.05). CONCLUSIONS: The majority of PVs could have been targeted and successfully isolated using exclusively the novel EAS irrespective of their anatomy assessed by pre-interventional CMRI. Considering the economical impact of CMRI and its minor influence on ablation strategy, success, and safety it is not an essential pre-requisite for subsequent successful EAS-based PVI.

Esophageal temperature change and esophageal thermal lesions after pulmonary vein isolation using the novel endoscopic ablation system.

BACKGROUND: Pulmonary vein isolation (PVI) is an established treatment option for paroxysmal atrial fibrillation. Recently, a novel endoscopic ablation system (EAS) was introduced. The incidence and severity of ablation-induced esophageal thermal lesions (ETLs) are unknown. OBJECTIVE: The purpose of this study was to investigate the incidence and severity of ablation-induced ETLs. METHODS: This prospective analysis compared two groups: group A underwent EAS-based PVI, and group B received PVI using radio frequency current (RFC). If esophageal temperature measured via an endoluminal temperature probe exceeded 38.5°C, energy application was stopped immediately. Endoscopy was performed 2 days postablation. RESULTS: Forty patients (20 female, mean age 56 ± 10 years) were treated with the EAS system (group A). In 20 patients (seven female, mean age 63 ± 9 years) RFC-based PVI was performed (group B). Esophageal endoscopy was performed 2.1 ± 0.8 (group A) and 2.8 ± 1.2 days postablation (group B), respectively. In 7/40 patients (18%) in group A, thermal lesions (four thermal ulcerations, three minimal thermal lesions) were detected. In group B, 3/20 patients (15%) displayed thermal lesions (three minimal thermal lesions). All thermal lesions resolved upon repeat endoscopy performed 8 ± 6 (group A) and 5 ± 1 days (group B) after initial endoscopy. CONCLUSION: In the EAS group, ETLs were found in 18% of patients, as compared with in 15% in the RFC group. In patients with ETLs, ulcerations were found in 57% in the EAS group, as compared with 0% in the RFC group. This may indicate that the quality of thermal lesions is more severe in the EAS group. Further investigation is required.

One-year clinical outcome after pulmonary vein isolation using the novel endoscopic ablation system in patients with paroxysmal atrial fibrillation.

BACKGROUND: Pulmonary vein isolation (PVI) is an established treatment option for atrial fibrillation (AF). Recently the novel endoscopic ablation system (EAS) was introduced and proved potential for successful acute PVI. OBJECTIVE: This study sought to investigate the 1-year follow-up results after EAS-based PVI. METHODS: A total of 40 patients (20 female, age 57 ± 9 years) with a long history (5 ± 4 years) of drug-refractory (2 ± 1 antiarrhythmic drugs) paroxysmal AF were included into our analysis. PVI was performed using exclusively the novel EAS. Follow-up included regular telephonic interviews, Holter electrocardiographic (ECG) and transtelephonic ECG recordings. A symptomatic or documented AF episode >60 seconds after a blanking period of 3 months was defined as recurrence. RESULTS: A total of 155 PVs were targeted; 153 of 155 (99%) PVs were isolated successfully using exclusively the novel EAS. During a median follow-up of 402 (331 to 478; quartile 1 to quartile 3) days, 24 of 40 patients (60%) remained free of any symptomatic or documented AF episode without antiarrhythmic drugs after a single procedure. Seven patients suffering from AF recurrence underwent radiofrequency current-based Re-PVI 203 ± 102 days after the index EAS-based procedure. Left atrium to pulmonary vein reconduction was found in 17 of 25 initially isolated PVs. No PV stenosis was detected based on magnetic resonance imaging 3 months postablation. CONCLUSION: Patients after EAS-based PVI due to paroxysmal AF demonstrate 1-year single-procedure success rates similar to those of other ablation techniques and ablation energies. The major determinant for AF recurrence after EAS treatment seems to be reconnection of previously isolated PVs. More patients and longer follow-up periods are mandatory before final conclusions can be drawn regarding the efficacy and safety of the EAS.