PO-03-063 A POLYACRYLAMIDE (PAA) GEL PHANTOM FOR STUDYING CATHETER ABLATION

Benchtop studies are often used to evaluate cardiac ablation techniques, and commonly utilize ex-vivo animal tissues. While widely available, tissues do not consistently replicate live atrial tissue physical properties, adding variability. Tissue mimicking phantoms have been in non-cardiac studies, but their mechanical electrical properties may mimic tissue. Furthermore, analysis of lesions has limited 2D measurements lesion cross-sections, precluding volume measurement limiting accuracy. Polyacrylamide (PAA) gels, which modifiable elasticity, similar thermal human tissues, study liver ablation. The addition bovine serum albumin (BSA) – a protein that coagulates when heated beyond set temperature also shown provide optical MRI contrast ablated gels. aim this was develop reproducible phantom with realistic friction, impedance, enabling in-vitro replication 3D quantification using high resolution scans. Gels were mixed acrylamide concentrations from 3% 12% (g/mL) 2% BSA. Resulting Young's moduli coefficients friction measured custom tester. Reference frictional porcine aortic specimens the same methods. elasticity values derived literature. saline 20-40W power, for 20-40s, 10-20g contact force. Baseline impedances 125Ω by titrating salinity bath. Finally, gels imaged T2-weighted sequence on 3T scanner. fabricated reported Table 1, along reference values. 10.5-12% PAA gel matched contractile simulated properties. Ablations made optically visible coagulation coagulated BSA (Fig 1a) appeared hypointense T2-MRI 1b), automated thresholding. Measured dimensions comparable those prior enabled facilitated verification MRI.Tabled 1Table 1: aortae as compared literature valuesPhysical PropertyReferenceMeasured ValueMaterialValueMaterialValueYoung's Modulus (kPa)Ex-vivo left atrium28.0% gel32.6In-vivo ventricle20-200.210.5% gel68.1In-vivo skeletal muscle6.2-108.612.0% gel108.0Coefficient FrictionEx-vivo aorta0.02-0.046Ex-vivo aorta0.058±0.024Agarose gel0.03510.5% gel0.023±0.0014 Open table new tab