<em>In Situ</em> Laser Fenestration for Revascularization of the Left Subclavian Artery in Diseases of the Aortic Arch

Thoracic endovascular aortic repair (TEVAR) has become a widely established treatment for aortic arch pathologies in recent years. However, lesions near or involving the origin of the left subclavian artery (LSA) often present challenges in securing an adequate proximal landing zone. Various technical approaches, including parallel graft techniques, fenestration, chimney grafts, branched devices, and others, have been developed to optimize the proximal landing zone while preserving LSA perfusion. Among these approaches, in situ laser fenestration (ISLF) of the LSA has emerged as a highly versatile and safe technique, demonstrating high success rates. This article provides a comprehensive overview of perioperative management and critical procedural steps for performing ISLF of the LSA, and presents clinical outcomes from a consecutive case series with a technical success rate of 94.5%. The objective is to offer vascular surgeons and interventional radiologists detailed insights to support the safe and effective application of this advanced technique.