Multimodal PSOCT-NIRS catheter for guided ablation of atrial fibrillation.

Significance: Atrial fibrillation is treated with thermal ablation to isolate ectopic signals. Although this is the current standard of care, recurrence occurs in up to 40% of cases. Clinicians have no reliable way to predict treatment durability intraoperatively. Adding the capability of direct optical measurement of the tissue to an ablation catheter could help better guide the treatment. Aim: A radiofrequency ablation catheter was developed with polarization-sensitive optical coherence tomography (PSOCT) and near-infrared spectroscopy (NIRS) to demonstrate, for the first time, simultaneous monitoring of thermal lesion formation. Approach: We fabricated the multimodal PSOCT-NIRS ablation catheter and validated optical metrics using known targets of tissue-like phantom, deoxygenated blood, and atrial tissue. We then demonstrated recording PSOCT and NIRS data during Results: PSOCT-NIRS metrics showed expected values in known targets. Measurements during ablation also exhibited previously reported patterns-OCT scattering increases, PSOCT birefringence decreases, and NIRS lesion optical index increases. Furthermore, simultaneous measurement revealed varying rates of change and magnitudes of response to different powers of thermal ablation. Conclusions: PSOCT-NIRS can measure tissue response to thermal energy delivery, and the optical metrics are complementary. By collecting more information during thermal energy delivery, PSOCT-NIRS metrics could contribute to understanding treatment durability in future investigations.