Efficient and Selective Ablation of Atheroma Using Watt-Level Mid-Infrared Femtosecond Laser at 5.75 µm

Abstract

Atherosclerotic cardiovascular disease remains a leading cause of global mortality. Despite advancements in pharmacological therapies and invasive interventions, including stenting and bypass surgery, current approaches are constrained by severe side effects, risks of restenosis and perioperative complications, significant recovery burdens, and high damage to vascular tissues. There is a critical need for a minimally invasive technique capable of selectively ablating atheromatous lesions while preserving healthy vascular tissues. In this study, leveraging the unique molecular composition of atherosclerotic plaques—rich in cholesteryl esters, and substantial spectral separation between the ester and artery absorption, selective laser ablation of atheroma is demonstrated. A 5.75 µm femtosecond laser system targeting the resonance of cholesteryl ester bonds, with a high power of 1.5 W is developed based on parametric amplifiers, to assess ablation efficiency and selectivity. The atherosclerotic plaques in a murine model of atherosclerosis are fully removed within milliseconds, while no damage to the artery is observed. Furthermore, the translational potential of this technology is validated by integrating a specially designed mid-infrared anti-resonant hollow-core fiber for efficient laser energy delivery, achieving an ablation rate of 0.13 mm³ s⁻¹. These findings provide a promising strategy for rapid and selective intervention in atherosclerosis, with clear potential for clinical translation.