Ablation of Persistent Atrial Fibrillation Using Multielectrode Catheters and Duty-Cycled Radiofrequency Energy

Abstract

This initial 50-patient multicenter study demonstrates a 80% short-term and 66% success rate at 20 months, with a low complication rate and a relatively short procedure time in patients with persistent AF using 3 anatomically specific multielectrode ablation catheters and low-energy duty-cycled radiofrequency energy.

Multielectrode phased radiofrequency ablation compared with point-by-point ablation for pulmonary vein isolation – outcomes in 539 patients

“…5,7,8 However, the number of patients in published reports remains limited; there are few publications that outline experiences with PVAC under conditions of actual care, and comparisons with Carto ® (Biosense Webster, Inc., Diamond Bar, CA, USA) and NavX™ (St Jude Medical, Inc., Saint Paul, MN, USA) are rare. 9,10 In addition, there are few data available on the technology in patients with persistent or long-lasting AF.…”

“…PVAC is employed together with a multichannel RF generator (GENius; Medtronic, Minneapolis, MN, USA) that enables synchronous uni-and bipolar RF energy delivery to any combination of PVAC electrodes. 7,8 Mapping is performed by bipolar recordings through adjacent electrode pairs.…”

Ablation of Long-Standing Persistent Atrial Fibrillation

“…3 However if longstanding persistent atrial fibrillation is present (defined as event duration > 6 months 4 or > 1 year 5 ) greater left atrial substrate modification is necessary. [6][7] Since the atrial substrate is remodeled heterogeneously, the ablation protocol and outcomes are operatorbiased, and left atrial flutters can occur after ablation. 7 In longstanding fibrillation, large lesions are often needed with electrical isolation of large swaths of free wall, which may be difficult due to current limitations in catheter ablation technology.…”

“…[6][7] Since the atrial substrate is remodeled heterogeneously, the ablation protocol and outcomes are operatorbiased, and left atrial flutters can occur after ablation. 7 In longstanding fibrillation, large lesions are often needed with electrical isolation of large swaths of free wall, which may be difficult due to current limitations in catheter ablation technology. 8 Chronically remodeled atria may become so structurally and electrophysiologically altered that arrhythmia is maintained even with extensive catheter ablation.…”

“…8 Chronically remodeled atria may become so structurally and electrophysiologically altered that arrhythmia is maintained even with extensive catheter ablation. 9 Extensive lesion size can increase risk of collateral damage, affect atrial transport function and coronary sinus patency, 3,7 it can promote arrhythmia development, and may even be proarrhythmic. 3 To improve outcome in treatment of longstanding persistent AF, attention has centered on detection of areas of slowed conduction and wavefront pivot caused by tissue anisotropy, as well as regions of fibrotic change, both of which can cause electrogram fractionation.…”