SPC365

Sinus rhythm endocardial mapping for channels’ identification in ischemic ventricular tachycardia using a modified electrophysiological triad

Session: Comunicações Orais (Sessão 1) - Arrítmias 1 - Taquicardia ventricular
Speaker: Pedro Adragão

Congress: CPC 2022
Topic: C. Arrhythmias and Device Therapy
Theme: 08. Ventricular Arrhythmias and Sudden Cardiac Death (SCD)
Subtheme: 08.4 Ventricular Arrhythmias and SCD - Treatment
Session Type: Comunicações Orais
FP Number: ---
Authors: Pedro Adragão; Daniel Matos; Pedro Galvão Santos; Francisco Moscoso Costa; Gustavo Rodrigues; João Carmo; Maria Salomé Carvalho; Pedro Carmo; Francisco Morgado; Diogo Cavaco; Miguel Mendes

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">Background:</span></span></strong> <span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">In a previous study it was demonstrated that an electrophysiological triad was able to identify critical isthmus in atrial flutter (AFL) patients.&nbsp; This triad is based in th<span style="color:black">e Carto&reg; electroanatomical mapping (EAM) version 7, which displays a histogram of the local activation times (LAT) of the tachycardia cycle length (TCL), in addition to the activation and voltage maps. </span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:black">Objective</span></span></span></strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:black">: This </span></span></span><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">study aimed to prospectively assess the ability of a modified electrophysiological triad to identify and localize the ventricular tachycardia&rsquo;s (VT) channels and entrance zones during sinus rhythm mapping.</span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">Methods:</span></span></strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif"> Prospective analysis of a unicentric registry of individuals who underwent ischemic VT ablation with Carto&reg; EAM, all in sinus rhythm. All patients with non-ischemic etiology, lack of high-density EAM or lack of mapping in any of the left ventricle walls or structures were excluded. <span style="color:black">Areas of late potentials and possible channels of re-entry were compared to a modified electrophysiological triad constituted by: areas of low-voltage (&lt;0.5mV), a site of deep histogram valley (LAT-Valley) with less than 20% density points relative to the highest density zone and a prolonged LAT-Valley duration that included 10% or more of the total activation time mapped. We also assessed the relationship between the pre-valley bar (the LAT histogram bar immediately before the prolonged LAT-Valley) and the channel entrances.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">Results: </span></span></strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">A total of 14 patients (14 men, median age 70 IQR 64-78 years) were included. All patients presented with ischemic VT and 86% had a previous inferior myocardial infarction. The median number of collected points were 1733 (IQR 1363-2729). All sinus rhythm maps presented with at least 1 LAT-Valley in the analysed histograms. All arrhythmias were effectively treated after undergoing radiofrequency in the LAT-Valley location, either by blocking the channel entrances or scar homogenization ablation strategy. <span style="color:black">Also, the pre-valley bar in the histogram marked all the channel entrances in the scar borders. No patient had relapse after a clinical follow up of over 6 months.</span></span></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif">Conclusion: </span></span></strong><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif"><span style="color:black">In a prospective analysis, a modified electrophysiological triad was able to identify the scar channels in sinus rhythm in all patients. The pre-valley bar in the histogram disclosed the channel entrances.</span></span></span><span style="font-size:10.5pt"><span style="font-family:&quot;Arial&quot;,sans-serif"> Further studies are needed to assess the usefulness of this algorithm to simplify catheter ablation and improve clinical outcomes.</span></span></span></span></p>