In situ fenestration (ISF) versus single-branched stent graft (SBSG) implantation in the management of acute Stanford type B aortic dissection involving the left subclavian artery.

Background: With the advances in medical technology and materials, thoracic endovascular aortic repair has become the mainstay of treatment for aortic dissection. In situ fenestration (ISF) and single-branch stent graft (SBSG) implantation are commonly used methods, with each having its own advantages and disadvantages. The study aimed to compare the perioperative outcomes and one-year follow-up results of patients who underwent ISF or SBSG in the treatment of acute Stanford type B aortic dissection involving the left subclavian artery (LSA).

Methods: From January 2018 to December 2022, consecutive patients with Stanford type B aortic dissection were retrospectively recruited and divided into ISF group and SBSG group according to the type of surgery. The patient's aortic physiology was evaluated by computed tomography angiography at 1, 3, 6, and 12 months after discharge.

Results: This study included 67 patients in the SBSG group and 21 patients in the ISF group. The baseline and preoperative indices were similar between the groups. The success rate of perioperative treatment was 100%, and no adverse consequences occurred in either group. No spinal cord ischemia, stroke, or paraplegia occurred in either group during the one-year follow-up. The rate of endoleak in the SBSG group was significantly lower (3%, all type I endoleaks) than that in the ISF group (9.5% type I and 14.3% type II endoleaks) (P=0.005). Type II endoleak mainly occurred in the LSA. In addition, complete thrombosis of the false lumen was achieved in 95.5% of the SBSG group versus 81.0% of the ISF group, but this was not a significant difference (P=0.091). The maximum diameter of the true lumen increased significantly in the ISF (P<0.001) and SBSG (P<0.001) groups. Meanwhile, the maximum diameter of the false lumen was significantly reduced in the ISF (P<0.001) and SBSG (P<0.001) groups, but the difference in the maximum diameter change of the true or false lumen between the two groups was not statistically significant (P>0.05).

Conclusions: SBSG was associated with a significantly lower incidence of endoleak than was ISF. However, there were no differences observed in complete thrombosis of the false lumen. Further studies with larger sample sizes are needed to definitively establish which treatment is superior in terms of complete thrombosis of the false lumen.