[Diagnostic value of contrast-enhanced sonography and digital subtraction angiography for renal artery stenosis].

Objective: To evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) and digital subtraction angiography (DSA) for renal artery stenosis (RAS). Methods: Fifty-seven hypertensive patients suspected for RAS admitted in Beijing Hospital from September 2017 to August 2018 were enrolled. All 114 renal arteries were assessed by CEUS and DSA. RAS was subdivided into low-(30%-50%), moderate-(50%-69%) and high-grade (70%-99%) subgroups. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were compared between CEUS and DSA results. Results: Fifty-seven hypertensive patients (31 males, mean age 57.1 years) involving 114 renal arteries were included. Overall, DSA identified RAS in 71(62.3%) renal arteries, mild RAS, 34(29.8%); moderate RAS, 23(20.2%); severe RAS, 14(12.3%). With CEUS, the sensitivity, specificity, accuracy, PPV and NPV for detecting mild-grade RAS were 85.3%, 97.3%, 91.5%, 96.7% and 87.8%; for detecting moderate-grade RAS were 82.6%, 97.9%, 92.9%, 95.0% and 92.2%; for detecting high-grade RAS were 85.7%, 98.2%, 95.8%, 92.3% and 96.5%. The measure of agreement kappa was 0.92 between CEUS and DSA. Conclusion: CEUS is a safe and accurate method for the diagnosis and severity classification of RAS, especially those with kidney injury.