Analysis of the Spatio-Temporal Dynamics of Thermal Lesion Formation in Radiofrequency Cardiac Ablation

Atrial fibrillation (AF) is the most recurrent type of cardiac arrhythmia that causes a major socio-economic burden as associated with significant morbidity and mortality. Radiofrequency catheter ablation (RFCA) is a leading clinical practice for the treatment of AF. The aim of the procedure is to induce necrosis in the ectopic foci responsible for the altered electrical pathway through temperature increments provoked by radiofrequency delivery. In this context, temperature is a key factor as determines the size of the produced thermal lesions and, in turn, the success or the failure of the treatment. As consequence, several methods have been exploited for RFCA temperature monitoring, but with several limitations. In recent times, the feasibility of using fiber Bragg grating (FBG) sensors for high-resolved and distributed temperature measurements in ex vivo myocardial swine tissues has been assessed. In this study, the heat diffusion within the tissues was investigated by producing 2D thermal maps based on multipoint FBG temperature data. Furthermore, the influence of both the delivered power and the treatment time on the dimensions of the produced thermal lesion was explored. The present research may lay the basis for the development of a model describing the spatio-temporal dynamics of the lesion formation. Such model may offer support to clinicians in selecting the proper RFCA settings.