Elastography imaging can provide radiofrequency ablation (RFA) lesion assessment due to tissue stiffening at the ablation site. An important aspect of assessment is the spatial and temporal stability of the region of stiffness increase in the peri-ablation period. The aim of this study was to use two ultrasound-based elastography techniques, shear wave elasticity imaging (SWEI) and acoustic radiation force impulse (ARFI) imaging to monitor the evolution of tissue stiffness at ablation sites in the 30 minutes following lesion creation. In 6 canine subjects, SWEI measurements and 2-D ARFI images were acquired at six ventricular endocardial RFA sites before, during, and for 30 minutes post ablation. An immediate increase in tissue stiffness was detected during RFA, and the area of the post-ablation region of stiffness increase (RoSI) as well as the relative stiffness at the RoSI center were stable approximately 2 minutes after ablation. Of note is the observation that relative stiffness in the region adjacent to the RoSI increased slightly during the first 15 minutes, consistent with local fluid displacement or edema. The magnitude of this increase, ∼0.5-fold from baseline, was significantly less than the magnitude of the stiffness increase directly inside the RoSI, which was greater than 3-fold from baseline. Ultrasound-based SWEI and ARFI imaging detected an immediate increase in tissue stiffness during RFA, and the stability and magnitude of the stiffness change suggests consistent elasticity-based lesion assessment is possible 2 minutes after and for at least 30 minutes following ablation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Stephanie A Eyerly, MARYAM VEJDANI-JAHROMI, Douglas M Dumont, Gregg E Trahey, Patrick D Wolf
Journal of cardiovascular electrophysiology, (26)9, 1009–1018.
Complex networks, Complex Systems, Computation and Language, and Computational Finance