The predictive value of tissue response viewer for lesion transmurality in a porcine model.

BACKGROUND: The tissue response viewer (TRV) is a multiparametric index that incorporates time, power, tissue pressure, impedance, and wall thickness data during radiofrequency catheter ablation (RFCA) and is used to predict the transmurality of lesions. This study aimed to evaluate the feasibility and accuracy of the TRV in a porcine model. METHODS: Twelve pigs underwent preablation high-density voltage and activation mapping of two atria, and both were repeated after linear RFCA. Intentional gaps were kept in the left atrium (LA) and were touched up in the right atrium (RA). Standard and high powers were, respectively, performed in the LA ablation. Six pigs were immediately sacrificed for pathological examination after the mapping and ablation procedure (acute study). Another six pigs were kept for 4 weeks before remapping and pathological examination (chronic study). RESULTS: All animals completed the planned procedure. The TRV function showed a sensitivity of 97.1% and a specificity of 76.9% in the acute study, and a sensitivity of 95.9% and a specificity of 72.5% in the chronic study to predict the transmural lesion. All positive and negative predictive values were over 80%. In addition, the TRV achieved higher sensitivity (92.3% vs. 85.0%) and specificity (88.2% vs. 78.9%) to predict the transmural lesion in LA ablation with high power compared with standard ablation. CONCLUSIONS: This study presents the histopathological validation of TRV to predict transmural lesions. The use of TRV may guide a more individual ablation and a more precise touch-up of gaps for atrial arrhythmias.