6533b831fe1ef96bd1298acc

RESEARCH PRODUCT

CATHAR : CATHeter for ARRhythmias : determination of depth of burned biological tissues with microwave

subject

description

Cardiac arrhythmia substrates may be treated by intracardiac ablations which consist in burning specific atrial or ventricular endocardial substrates. Created lesions which are not transmural may be responsible for arrhythmia recurrences. To date, the depth of the lesion inside the endocardium can't be assessed accurately during the procedures. Our experimental work has focused on microwave characterization of biological tissues (in vitro) to assess the burn depth. Using a reflection technique with a coaxial probe in contact with tissues, measurements were made over a wide frequency range (100 MHz to 6 GHz). The measured reflection coefficient is known to be directly related to the dielectric properties of the tissues. We therefore measured the relative variation of the reflection of the tissue. In order to determine the burn depth of the tissue, the imaginary part of the relative variation is studied as a function of the real part of the relative variation for each frequency. Thus, we observe an evolution of the signal as a function of the burn depth. The determination of the tissue burned depth in a liquid medium is possible.