Microwave Imaging Based Lesion Monitoring During Infarct Ablation: Feasibility Study

Sudden cardiac death rate post-myocardial infarction due to arrhythmia is increasing. Cardiac ablation of infarcts is shown to reduce arrhythmogenic events. Current methods are inadequate to monitor the lesions during infarct ablation. Therefore novel noninvasive tools are necessary to provide real-time monitoring of ablation and to titrate the ablative power to reduce arrhythmogenicity. The purpose of this simulation study was to demonstrate the feasibility of microwave imaging (MWI) to monitor the temperature profile of the lesions during infarct ablation. A 2D model of the left ventricle was used with an infarct region of interest for microwave imaging electromagnetic simulation at 915 MHz using known myocardial dielectric properties and its temperature dependence. Distorted Born Iterative Method (DBIM) was used to reconstruct the relative permittivity that is mapped to the temperature field and compared within the infarct region. Good agreement was observed between the reconstructed and assigned temperature field within the infarct region. The study demonstrates the feasibility of using MWI for the non-invasive assessment of infarct tissue temperatures during ablation.