Electroanatomic Mapping System – the useful tool for electrophysiology-Zając.indd

During over 20 years of development of catheter-based technologies in the management of cardiac arrhythmias, electroanatomic mapping systems have evolved significantly. Unique features of the systems such a non-fluoroscopic catheter localization or displaying activation and voltage maps, allow to target more challenging arrhythmias, reduce fluoroscopy exposure and decrease complications occurrence. New types of fractionation and score maps help to identify origin of complex arrhythmias. These tools allow to a patient-tailored approach. We present the usage of electroanatomic mapping systems during procedures of arrhythmia ablation. The principles of creation of activation, voltage, fractionation and score maps and their implementation in clinical practice were discussed. European Journal of Medical Technologies 2016; 4(13): 17-26 Copyright © 2016 by ISASDMT All rights reserved www. medical-technologies.eu Published online 31.12. 2016 EJMT 4(13) 2016 • European Journal of Medical Technologies 18 Copyright © 2016 by ISASDMT Introduction Electroanatomic mapping systems have been introduced into clinical electrophysiology over two decades ago [1-2]. In principle, such systems consist of three different parts: non-fluoroscopic catheter localization, calculation of electrical activation sequences and voltage maps [3-5], 3D display of the anatomy from serially generated catheter localization information [6]. These systems are used during cardiac ablations, aimed at destroying heart tissues responsible for the arrhythmia using flexible catheter [7]. The systems are based on non-fluoroscopic visualisation of mapping catheter and 3D reconstruction created by the manipulation of a mapping catheter [8]. Electrical information is recorded at a map and can be used for the color-coded display of the electrical activation sequence known as “activation mapping”, or the display of unipolar/bipolar electrograms (recorded from catheter leads inside a heart) as part of “fractionation” or “voltage mapping” [9-11]. The systems also allow to display catheter position and stored electrograms with anatomic information of the target chamber generated through other imaging modalities, mainly computed tomography and magnetic resonance tomography [12]. This additional functionality is often referred to as image fusion [13]. In this context, achieving electrically continuous, transmural lesions in a beating heart is challenging and requires a reliable three-dimensional (3D) navigation, in order to avoid complications (AV nodal block, PV stenosis, perforation, phrenic nerve or esophageal injury) [14-15]. These systems have shown promising results for ablations and have been proven to reduce radiation and procedural duration and can lead to less complications and better results [16-18]. The concept of high-density mapping refers to the simultaneous acquisition and annotation of multiple electrograms, including activation and voltage information, which are then analyzed by automated algorithms in order to generate precise activation and substrate (voltage) maps. These algorithms were initially applied for macro-reentrant tachycardia, but then have been further developed and adapted for complex arrhythmias like atrial fibrillation. In order to achieve this novel mapping catheters have been developed. Multiple electrodes serve for fast acquisition of data whereas a smaller electrode size and a shorter inter-electrode distance provide a better signal quality with less noise to far field ratio (Fig. 1) [19]. Mapping systems direct towards a new era of substrate characterization and individual ablation strategies. These tools aim to identify additional ablation targets and allow to a patient-tailored approach [20]. Electroanatomic Mapping System – useful tool for electrophysiology Currently, there are few electroanatomic mapping systems available on the market. The most recent, launched on the market in 2016, is called EnSite PrecisionTM [Abbott (St. Jude Medical)]. This system meets all requirements in terms of forming reliable and stable 3D heart model, fast creating high-density activation and voltage maps and displaying them on the prepared geometry [21].