Introduction
Although pulmonary vein isolation (PVI) is the gold standard for AF catheter ablation, stand-alone PVI for persistent AF is associated with an increased recurrence rate.1 Many alternative treatments have been proposed to improve prognosis for persistent AF; however, to date, none has proven to be effective for this condition.2
An ablation approach targeting focal discharge is a recently proposed strategy beyond PVI. Previous studies demonstrated that focal activations may play an important role in AF maintenance and drivers, and ablation targeting focal activations may be promising as a therapeutic approach for persistent AF.3-8 However, the underlying mechanisms of generation of focal activations remain poorly understood, and little is known about the specific types of focal activation associated with AF and whether all focal activations are necessary for AF persistence. In addition, identification of the focal activation during AF is a challenging task requiring special equipment.
CARTOFINDER is a commercially available, novel mapping system that can identify potential AF drivers and focal activations by analyzing a wavefront propagation on the CARTO®3 version 7 platform (Biosense Webster Inc., Diamond Bar, CA, USA).8-10 A detailed analysis of the electrical characteristics and patterns of the focal activation using the novel mapping algorithm may provide insight into the mechanism of AF drivers.
Thus, the present study was conducted to evaluate the electrical features of the focal activations presented by the CARTOFINDER system and to identify high-priority focal activations associated with the maintenance of AF by analyzing the distribution and characteristics of the dominant cycle length (DCL) in the CARTOFINDER mapping system.