New imaging techniques in ventricular tachycardia ablation: integration of myocardial thickness analysis software in computed tomography with omnipolar mapping

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Magnetic resonance imaging (MRI) is very useful for planning the ablation of ventricular tachycardias (VT) related to scar, since it allows identification of anatomy, scar dense/border zone (DZ/BZ) and conduction channels (CC). However, access to this test is limited in many centres and, in addition, artefacts generated by pacing/defibrillation devices (ICDs) can often make it uninterpretable. Multidetector cardiac computed tomography (MDCT) offers the advantages of greater accessibility, better anatomical characterisation and less device artefacts, although there is little experience of its use. Purpose The objective is to evaluate the effectiveness of integrating myocardial thickness analysis software with MDCT and omnipolar electroanatomical mapping for VT ablation procedures in patients with cardiomyopathy. Methods Single-centre, descriptive study of a serie of patients, ICD carriers, that underwent VT ablation: - Patient 1- 72-year-old male with ischaemic heart disease. - Patient 2- 46-year-old male with left arrhythmogenic cardiomyopathy. - Patient 3- 60-year-old male with biventricular arrhythmogenic cardiomyopathy. - Patient 4- 28-year-old female with right arrhythmogenic cardiomyopathy. MDCT was performed on all patients and the images were post-processed using myocardial thickness analysis software. A 3D colour map was created with identification of the DZ, BZ and CC. This map was fused with the electroanatomical map created during the electrophysiological study with omnipolar technology. Results In all cases there was a high anatomical correlation between DZ, BZ and CC detected on postprocessed MDCT and the area of pathological voltage and late electrograms of the omnipolar map. In patient-1, the CC detected on CT coincides with the diastolic corridor of clinical VT (image 1A). In patient 2, CT analysis identified the direct relationship of the circumflex artery with the superior region of the DZ (image 1B). In patients 3 and 4, the CT scan identified the relationship of the DZ/BZ in the right ventricular outflow tract with the coronary arteries and phrenic nerve (image 1 C and D). Conclusions The computed tomography myocardial thickness analysis software is positioned as an alternative to MRI in VT ablation, as it localises critical anatomical structures and identifies the scar dense/border zone and conduction channels accurately.