In-situ laser and radiofrequency fenestration in TEVAR for left subclavian artery revascularization.

Thoracic endovascular aortic repair (TEVAR) is standard for descending thoracic aortic disease. When disease involves the proximal arch (zones 0-3), left subclavian artery (LSA) coverage is often required, increasing stroke and spinal cord ischaemia risk if unrevascularized. Guidelines recommend routine LSA revascularization, traditionally via surgical bypass, though with notable morbidity. Endovascular alternatives include fenestrated/branched devices, chimneys, and in-situ fenestration. This narrative review aims to provide a summary of existing knowledge on laser in-situ fenestration (ISLF) and radiofrequency fenestration for LSA revascularization. ISLF provides high technical success, durable patency, and low perioperative risk, with expanding use in urgent and complex cases. Long-term durability, however, remains uncertain and requires further study.