Role of Intravascular Ultrasound for In Situ Sizing and Technical Assessment of Directional Branches During Branched Endovascular Aortic Repair

Abstract

To compare intraoperative and early outcomes of branched endovascular aortic repair (BEVAR) of thoracoabdominal aortic aneurysms with or without the use of intravascular ultrasound (IVUS). We conducted a single-center retrospective study of consecutive patients treated for thoracoabdominal aortic aneurysms with branched devices (2019-2021). Two groups were compared. In standard BEVAR (s-BEVAR), sizing was based exclusively on the preoperative computed tomography angiogram, and the technical assessment consisted of intraoperative angiography. From 2020 (iv-BEVAR), IVUS (Philips platform with 0.035-in. Volcano IVUS catheter) was routinely used for in situ sizing of the bridging stent (diameter and length of the distal landing zone, total bridging stent length) and for technical assessment of the bridging stent after deployment (kink, compression, malapposition, or inadequate sealing). s-BEVAR and iv-BEVAR patients were compared in terms of procedural metrics (duration of surgery, radiation dose, radiation time, and contrast volume), technical success (successful introduction and deployment of the device and bridging stents, in the absence of surgical conversion or mortality, type I or III endoleak, branch occlusion, or graft limb obstruction), and 30-day outcomes. There were 59 target vessels (n = 15 patients) in the s-BEVAR group and 56 (n = 15 patients) in the iv-BEVAR group. Aneurysm anatomic classification was similar (extent I-III, 73% vs 67%; extent IV, 27% vs 33%; P = .999). Comparing s-BEVAR vs iv-BEVAR, the total operating time (280 ± 62 minutes vs 293 ± 84 minutes; P = .073) and contrast volume (168 ± 42 mL vs 153 ± 38 mL; P = .312) were similar, although iv-BEVAR had a lower radiation time (119 ± 35 minutes vs 92 ± 42 minutes; P = .042) and dose (745 ± 75 Gy vs 635 ± 85 Gy; P = .010). The use of IVUS identified a significant branch technical defect in 8 of 56 target vessels (14%) not identified by standard angiography; bridging stent compression in five cases and incomplete stent-to-wall apposition in three. These were all intraoperatively corrected with success. Technical success was 100% for both groups, and there were no postoperative deaths and no IVUS-related complications. At 30 days, there were no complications related to the main endograft or directional branches. The use of IVUS for in situ sizing and technical assessment of BEVAR was safe and allowed for reduced radiation time and exposure during BEVAR, maintaining a similar operating time. Compared with sole angiography, the intraoperative use of IVUS led to adjunctive intraoperative maneuvers in a non-negligible portion of target vessels. Further studies are needed to evaluate the clinical role of IVUS in BEVAR.