High-density automated mapping and entrainment pacing for successful atypical flutter ablation with one RF application.

Abstract

Atypical left atrial flutter may occur as a complication after atrial fibrillation ablation, especially when linear and substrate ablation were initially deployed. In such cases, the most effective therapy is radiofrequency ablation, but the procedure can be long lasting and challenging. Use of multielectrode catheters and high-density mapping algorithms together with a conventional electrophysiological approach may shorten and simplify treatment. Case reportA 43-year-old woman, after previous ablations for atrial fibrillation and typical atrial flutter, was scheduled for another ablation, due to symptomatic atypical atrial flutter. Echocardiography showed left atrial (LA) diameter within the normal range (40 mm) and normal ejection fraction (65%).Previously the patient underwent circumferential pulmonary vein isolation and linear ablation with lines in the cavo-tricuspid isthmus (CTI), left atrial roof and mitral isthmus groove. During the last ablation, bi-directional block was confirmed in all locations and no arrhythmia was induced with aggressive stimulation during isoproterenol infusion.The ECG recorded on admission suggested left atrial flutter with 2:1 conduction, with positive F waves in leads II, III, aVF, and V1 and negative in leads aVR and AVL (Fig. 1). Intracardiac signals (IC) showed atrial flutter with CL 295-300 ms, with proximal and distal bipoles at the catheter placed in the coronary sinus (CS) activated simultaneously.Due to the electrographic pattern of arrhythmia and previous catheter ablations the operator (JK) decided to perform high-density mapping of left atrial endocardial activation using a multielectrode mapping (MEM) catheter (PentaRay, 20 poles, spacing 2-6-2, 1 mm width electrodes) and dedicated automatic algorithm[1] (Confidense, Carto 3 Biosense Webster).

Ultra–fast, high density 3D mapping system for catheter ablation of atypical atrial flutter.

“…Constructing a high-resolution map allowed for precise location of arrhythmia, and thus establishing the detailed area from where it has originated. There are no clinical data comparing Rhythmia with other mapping systems or single-center experiences showing that other systems could also be efficient in the ablation of atypical AFl [5] . Speeding up the process of gathering a lot of information in a short time using the Rhythmia system can be crucial in hemodynamically unstable patients or in those who have potentially life-threatening arrhythmias such as the electrical storm [6] .…”

“…The INTELLAMAP Orion Mapping Catheter was used to create an ultra high-density electro-anatomical model of LA. The catheter is equipped with 64 deployable electrodes (range 3-22 mm) arranged in 8 splines [5] . The number and density of points were sufficient to draw an activation map of LA ( Figure 2) and located the place where the arrhythmia originated.…”