In Situ Laser Fenestration for Zone 2 TEVAR: A 15 Year Experience Demonstrating Its Safety, Efficacy, and Durability.

Introduction: In situ laser fenestration (ISLF) of the left subclavian artery (LSA) is a simple and effective method for left subclavian artery revascularization. However, long-term outcome data for this technique are lacking. This study presents our expanded experience with long-term outcomes of ISLF of the LSA in zone 2 thoracic endovascular aortic repair (TEVAR).

Methods: A single-center retrospective review of all consecutive patients who underwent zone 2 TEVAR with LSA revascularization by ISLF was performed (2009-2023). This technique was performed through retrograde percutaneous or open brachial arterial access. A thoracic endograft was deployed in zone 2 followed by ISLF using a 2.3 mm laser. A balloon expandable covered stent was placed across the fenestration and post-dilated. Postoperative clinical follow-up and computed tomography angiography (CTA) were reviewed to assess our endpoints. Primary endpoint was fenestration-related endoleak reintervention (type Ic or IIIc). Secondary endpoints were early and late stroke rates, LSA stent patency, fenestration-related mortality (FRM) and aorta-related mortality (ARM).

Results: 81 patients were included in our series (48 males (59%), mean age 60.9 ±12.8 years). Indication for intervention was type B aortic dissection in 67 patients (82.7%). 92% of all interventions were urgent or emergent, with 19 patients presenting with rupture (23.5%). ISLF was successfully performed in all 81 cases. Median operative time was 153 minutes. Post-intervention stroke occurred in 3 patients (3.7%) and spinal cord injury in 6 patients (7.4%, 3 transient, 3 permanent). There were 9 operative mortalities (11.1%). Median clinical follow-up was 4.3 years (range 0-12.6), and median imaging follow-up was 4.3 years (range 0-12.5). 3 patients (3.7%) were found to have a type 1c endoleak and underwent distal extension of the LSA stent at 6.6, 23.6, and 30.2 months postoperatively. Importantly, there was no fenestration-related type IIIc endoleak or mortality. Primary LSA stent patency was 100% at 1 year, 96.7% at 5 years and 91.1% at 10 years. Freedom from fenestration-related endoleak reintervention was 98.4% at 1-year, 93.2% at 5 years and 93.2% at 10 years. There was only 1 late-aortic-related death (1.4%) secondary to multiorgan failure on postoperative day 77 after visceral debranching.

Conclusions: ISLF for LSA revascularization is a safe, reproducible, and durable treatment option in TEVAR requiring proximal seal in zone 2. ISLF carries an excellent technical success rate, low fenestration-related complications, and competitive long-term stent patency. Low stroke rate and short operative time further support ISLF as an effective surgical technique for LSA revascularization.