Omnipolar technology in ventricular tachycardia ablation: activation and substrate mapping with late activation isochrone analysis under extrastimulus protocol

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The cornerstone of the ablation of eschar-related ventricular tachycardias (VT) is the circumscription of the scar dense zone (DZ)/border zone (BZ) and the identification of regions of slow decremental conduction. The anisotropy of the BZ generates depolarisation waves with rapid changes in their direction that may not be detected by bipolar electrodes, as their identification capacity is orientation-dependent. Omnipolar technology detects the direction and velocity of the wavefront regardless of its orientation. Purpose Describe the effectiveness of the use of omnipolar technology for the development of electroanatomical and activation maps during the study of VT related to scar. Methods Single-centre, observational, descriptive study of a serie of patients: - 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. - Patient 5- 42-year-old male with non-ischemic dilated cardiomyopathy. - Patient 6 - 73-year-old male with arrhythmogenic right cardiomyopathy. Omnipolar technology was used for the creation, under sensed extrastimuli in right ventricular apex protocol, of a voltage map, isochrone late activation map (ILAM), slow decremental conduction (SDC) analysis and, in case of VT induction, activation map with real-time visualisation of conduction vectors ("Strategic-multielectrode-positioning" / StaMP-mapping). Results In patients 1, 2 and 3 ILAM was performed identifying SDC regions. After induction of VT, StaMP-mapping was performed in these regions with identification of the diastolic corridor (image 1A, 1B, 1C). The corridor was eliminated and, subsequently, arrhythmogenic substrate ablation of late potentials in DZ/BZ was performed. In patients 4, 5 and 6 an identical protocol was performed, but VT induction was not achieved, so substrate ablation strategy was performed (image 1D, 1E, 1F). Patient 6 has had a recurrence of sustained VT. Conclusions Omnipolar technology, associated with the extrastimulus protocol, allows a more accurate study of scar-related VT, through the identification of SDC regions. These locations are current targets for substrate ablation and, in many cases, the origin of the critical isthmus.