Comparing Diagnostic Efficacy of Contrast-Enhanced US and CTA for Detecting Type 2 Endoleaks: A Comparison with Conventional Angiography and Assessment of Periprocedural Factors

Objective and Hypothesis: Contrast-enhanced US (CEUS) remains less widely accepted than CTA for endoleak surveillance after endovascular aortic aneurysm repair (EVAR), with type 2 endoleaks being a common early complication. Direct comparisons of CEUS, CTA, and conventional angiography are limited in the United States. We evaluated the diagnostic efficacy of CEUS versus CTA for detecting type 2 endoleaks, using conventional angiography as the reference standard, and assessed procedural factors during endoleak repair in patients with and without preprocedural CEUS. The null hypothesis is that no differences exist in diagnostic accuracy or procedural factors between CEUS and CTA, while the alternative hypothesis anticipates significant differences. Materials and Methods: This retrospective, single-institution study analyzed patients with suspected type 2 endoleak on CEUS and/or CTA following EVAR who underwent conventional angiography between October 2018 and July 2024. We compared the diagnostic outcomes of CEUS and CTA with conventional angiography and evaluated periprocedural factors such as time from the last contrast-enhanced imaging to angiography, sedation time, contrast dose, and fluoroscopy duration/dose. Results: The rate of type 2 endoleak detection on conventional angiography was similar between patients with preprocedural CEUS and those with CTA (90% vs 75.5%; P =.32). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CEUS for detecting endoleaks were 100%, 50%, 90%, and 100%, respectively. CTA had sensitivity, specificity, PPV, and NPV of 93.2%, 9.1%, 80.4%, and 25%, respectively. The median time from the last imaging to angiography was significantly shorter for patients with preprocedural CEUS compared with CTA (0 vs 23 days; P <.001). Intraprocedural factors (sedation time, contrast dose, and fluoroscopy duration/dose) were not statistically different (P >.05). Conclusions: CEUS was more reliable for ruling out clinically significant type 2 endoleaks and was associated with quicker access to confirmatory angiography than CTA. Sensitivity, endoleak detection rate, and procedural factors were similar between the modalities. These findings suggest CEUS is an equally accurate, yet potentially more efficient, alternative to CTA for EVAR surveillance.