CathCam-Guided Picosecond Infrared Laser Ablation in Peripheral Artery Disease Revascularization

Endovascular revascularization of peripheral arterial occlusions has a high technical failure rate of 15-20%, mainly due to difficulties in crossing the occlusion with a guidewire. This study evaluates the use of a Picosecond mid-Infrared Laser (PIRL) to facilitate occlusion crossing.

Popliteal artery lesion samples were obtained from a donated limb of a patient with critical limb ischemia (CLI). A customized system advanced the PIRL fiber at controlled speeds toward the occlusion. The fiber was tested with its source OFF and ON at either 500 mW or 1000 mW power, 2.96 µm wavelength, and 1 kHz repetition rate. Lesions were scanned using µ-CT before and after the test, and post-ablated tissues were analyzed histologically. The feasibility of using PIRL with the CathCam, an optical image-guided steerable catheter, was also assessed under X-ray fluoroscopy in an OR suite.

Tests showed a significant crossing success improvement with the laser ON vs. OFF (95.6% vs. 73.9%, p << 0.05) and a significant reduction in maximum force (5.5 ± 9.8 gr vs. 17.2 ± 12.3 gr; p << 0.05). Success rates generally decreased with increased fiber speed, ranging from 100% at 0.019 mm/s to 30% at 0.5 mm/s, while force increased. The results showed that 0.1 mm/s fiber advancement speed is the fastest speed with the highest crossing success rate. Histological analysis showed sub -50 µm tissue trauma post-PIRL-ablation.

PIRL plaque ablation is minimally invasive, and 0.1 mm/s was identified as the optimal fiber advancement speed.

PIRL, guided with CathCam, demonstrates high potential for endovascular revascularization procedures.