Utility of Intra-operative Cone Beam Computed Tomography in Endovascular Treatment of Aorto-iliac Occlusive Disease

Role of intravascular ultrasound for the technical assessment of endovascular reconstruction of the aortic bifurcation

OBJECTIVE

The aim of this study was to evaluate the role of intravascular ultrasound (IVUS) for the technical assessment of kissing stents (KSs) and covered endovascular reconstruction of the aortic bifurcation (CERAB) in the treatment of aortoiliac obstructive disease involving the aortic bifurcation.

METHODS

We conducted a single-center retrospective review of patients undergoing endovascular treatment of severe aorto-iliac obstructive disease (2019-2023). IVUS was performed in patients treated by KSs or CERAB according to preoperative indications, in cases of moderate/severe calcifications, mural thrombus, total occlusions, and lesion extension towards the proximity of renal or hypogastric arteries. Indications for IVUS-guided intraoperative revisions were residual stenosis or compression >30%, incomplete stent-to-wall apposition, or flow-limiting dissection at the landing site. Follow-up assessment was performed at 6 and 12 months, and then yearly. Thirty-day outcomes and 2-year patency rates were evaluated. Logistic regression was used to identify factors associated with significant technical defects detected by IVUS needing intraoperative revision.

RESULTS

IVUS was used for the technical assessment of 102 patients treated by KSs (n = 57; 56%) or CERAB (n = 45; 44%) presenting with severe intermittent claudication (39%), rest pain (39%), or ischemic tissue loss (25%). Twenty-nine significant technical defects were identified by IVUS in 25 patients (25%) who then had successful intraoperative correction by additional ballooning (n = 23; 80%) or stenting (n = 6; 20%). Patients with a severely calcified chronic total occlusion (odds ratio, 1.85; 95% confidence interval, 1.01-5.27; P = .044) or severely calcified narrow aortic bifurcation with <12 mm diameter (odds ratio, 2.34; 95% confidence interval, 1.10-8.64; P = .032) were at increased risk for IVUS-guided intraoperative revision. There were no postoperative deaths and no major adverse events. Two-year primary patency was 100%.

CONCLUSIONS

IVUS was used for the technical assessment of KSs/CERAB in a selected cohort of patients with severe aorto-iliac obstructive disease. This allowed the identification and intraoperative correction of a significant technical defect not detected by completion angiogram in one-quarter of patients, achieving optimal 2-year results. IVUS assessment of KSs/CERAB may be considered especially in patients with a calcified total occlusion or narrow aortic bifurcation.

Bare Stents for Iliac Chronic Total Occlusions ("TELIS"): A Prospective Cohort Study with a Midterm Follow-up

BACKGROUND

This study aims to assess primary bare stenting for iliac chronic total occlusions (CTOs) with midterm follow-up.

METHODS

From April 2013 to May 2016, all patients presenting with symptomatic iliac CTO were treated endovascularly and included in a prospective single-center cohort. Common iliac CTOs were treated with balloon-expandable bare-metal stents. External iliac lesions were treated with bare self-expandable nitinol stents. Primary end point was primary sustained clinical improvement. A total of 49 iliac CTOs were treated in 46 patients.

RESULTS

A total of 22 lesions were located at the level of the common iliac artery (45%), 20 at the external iliac artery (41%), and 7 extending to both (14%). Mean stenting length was 114.4 ± 49.8 mm. Technical success was 98%. Primary sustained clinical improvement was achieved for 93.4 ± 3.7% of patients at 12 months and 87.7 ± 5.2% at 24 months. Three in-stent thrombosis were observed with no restenosis in the remaining patients at 24 months. Freedom from target lesion revascularization was 93.3% ± 3.7% at 24 months. Three stent fractures were noted, none were symptomatic. Mean quality of life (EQ5D-3L) was significantly improved at 24 months (71.2 ± 20.3 vs. 52.4 ± 22.6, P = 0.001).

CONCLUSIONS

Our results showed that primary bare-metal stenting for iliac CTO is safe and efficient at 24 months and could be considered as a first-line strategy.

Optimizing imaging and reducing radiation exposure during complex aortic endovascular procedures

Improvements in endovascular technologies and development of custom-made fenestrated and branched endografts currently allow clinicians to treat complex aortic lesions such as thoraco-abdominal and aortic arch aneurysms once treatable with open repair only. These advances are leading to an increase in the complexity of endovascular procedures which can cause long operation times and high levels of radiation exposure. This in turn places pressure on the vascular surgery community to display more superior interventional skills and radiological practices. Advanced imaging technology in this context represents a strong pillar in the treatment toolbox for delivering the best care at the lowest risk level. Delivering the best patient care while managing the radiation and iodine contrast media risks, especially in frail and renal impaired populations, is the challenge aortic surgeons are facing. Modern hybrid rooms are equipped with a wide range of new imaging applications such as fusion imaging and cone-beam computed tomography (CBCT). If these technologies contribute to reducing radiation, they can be complex and intimidating to master. The aim of this review is to discuss the fundamentals of good radiological practices and to describe the various imaging tools available to the aortic surgeon, both those available today and those we anticipate will be available in the near future, from equipment to software, to perform safe and efficient complex endovascular procedures.