Remote vs. conventional navigation for catheter ablation of atrial fibrillation: insights from prospective registry data

BACKGROUND

Robotic (RNS) or magnetic navigation systems (MNS) are available for remotely performed catheter ablation for atrial fibrillation (AF).

OBJECTIVE

The present study compares remotely assisted catheter navigation (RAN) to standard manual navigation (SMN) and both systems amongst each other.

METHODS

The analysis is based on a sub-cohort enrolled by five hospitals from the multicenter German ablation Registry.

RESULTS

Out of 2442 patients receiving catheter ablation of AF, 267 (age 61.4 ± 10.4, 69.7% male) were treated using RAN (RNS n = 187, 7.7% vs. MNS n = 80, 3.3%). Fluoroscopy time [RNS median 17 (IQR 12-25) min vs. MNS 22 (16-32) min; p < 0.001] and procedure duration [RNS 180 (145-220) min vs. MNS 265 (210-305) min; p < 0.001] were significantly different. Comparing RAN (11%) to SMN (89%) fluoroscopy time (RAN 19 (13-27) min, vs. SMN 25 (16-40) min; p < 0.001), energy delivery (RAN 3168 (2280-3840) s vs. SMN 2640 (IQR 1799-3900) s; p = 0.008) and procedure duration [RAN 195 (150-255) min vs. SMN 150 (120-150) min; p = 0.001] differed significantly. In terms of acute and 12 months outcome, no differences were seen between the two systems or in comparison to SMN.

CONCLUSION

AF ablation can be performed safely, with high acute success rates using RAN. RNS results in less fluoroscopy burden and shorter procedure durations. Compared to SMN, a reduced fluoroscopy burden, prolonged procedure and ablation duration were observed using RAN. Overall, the number of RAN procedures is small suggesting low impact on clinical routine of AF ablation.

Catheter ablation for paroxysmal and persistent atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most common cardiac arrhythmia seen in cardiovascular departments. Treatments include medical interventions and catheter ablation. Due to uncertainties in medical therapies for AF, and the need to continue sinus rhythm, ablation has been recently considered as a viable alternative. Many new ablation methods based on pulmonary vein isolation (PVI) have been developed.

OBJECTIVES

The primary objective of this review was to assess the beneficial and harmful effects of catheter ablation (CA) in comparison with medical treatment in patients with paroxysmal and persistent AF. The secondary objective was to determine the best regimen of CA.

SEARCH METHODS

Searches were run on The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library Issue 3 2009, MEDLINE (1950 to August 2009), EMBASE (1980 to August 2009), the Chinese Biomedical Literature Database (1978 to August 2009) and the CKNI Chinese Paper Database (1994 to 2009) . Several journals published in Chinese were also handsearched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in people with paroxysmal and persistent AF treated by any type of CA method. Two reviewers independently selected the trials for inclusion.

DATA COLLECTION AND ANALYSIS

Assessments of risk of bias were performed by two reviewers, and relative risk (RR) and 95% confidence intervals (CI) were used for dichotomous variables. Meta-analysis were performed where appropriate.

MAIN RESULTS

A total of 32 RCTs (3,560 patients) were included. RCTs were small in size and of poor quality.CA compared with medical therapies: seven RCTs indicated that CA had a better effect in inhibiting recurrence of AF [RR 0.27; 95% CI 0.18, 0.41)] but there was significant heterogeneity. There was limited evidence to suggest that sinus rhythm was restored during CA (one small trial: RR 0.28, 95% CI 0.20-0.40), and at the end of follow-up (RR 1.87, 95% CI 1.31-2.67; I(2)=83%). There were no differences in mortality (RR, 0.50, 95% CI 0.04 to 5.65), fatal and non-fatal embolic complication (RR 1.01, 95% CI 0.18 to 5.68) or death from thrombo-embolic events (RR 3.04, 95% CI 0.13 to 73.43).Comparisons of different CAs; 25 RCTs compared CA of various kinds. Circumferential pulmonary vein ablation was better than segmental pulmonary vein ablation in improving symptoms of AF (p<=0.01) and in reducing the recurrence of AF (p<0.01). There is limited evidence to suggest which ablation method was the best.

AUTHORS' CONCLUSIONS

There is limited evidence to suggest that CA may be a better treatment option compared to medical therapies in the management of persistent AF. This review was also unable to recommend the best CA method.

Pulmonary vein isolation for the treatment of atrial fibrillation: past, present and future

Atrial fibrillation is the most common sustained cardiac arrhythmia and is associated with impaired quality of life and an increased risk of stroke and mortality. Antiarrhythmic drugs, currently the first-line therapy for patients without permanent atrial fibrillation, fail to prevent recurrences in over 50% and are associated with significant adverse effects. In the majority of cases, atrial fibrillation arises from the repetitive firing of myocytes in muscle sleeves that extend from the left atrium into the pulmonary veins. Pulmonary vein isolation has emerged as an effective treatment in selected patients. In this paper, the past and present roles of pulmonary vein isolation are described and the future developments of this technique are explored.