Objective: To determine the frequency of elevated peak systolic proper hepatic artery velocity (HAV) in patients with acute cholangitis and to determine the diagnostic performance of this metric relative to existing criteria.
Methods: Between 9/2016 and 11/2017, 107 patients clinically suspected to have cholangitis were referred for an abdominal ultrasound. Of these, 56 patients had HAV measurements and were included in the final analysis. Clinical and imaging features, including HAV, HAV resistive index (RI), portal vein velocity (PVV), biliary dilation, and presence of an obstructive etiology were extracted. The diagnostic performance of HAV was compared to the existing available clinical criteria (Charcot's triad and 2018 Tokyo Guidelines). Elevated HAV was defined as HAV > 100 cm/s. Presence of cholangitis was determined by the discharge summary following medical workup and admission or observation.
Results: 32% had cholangitis while 68% did not. Average HAV for patients with cholangitis was 152 ± 54 cm/s versus 91 ± 44 cm/s for those without (p < 0.0001; t test). The HAV was elevated in 83% of patients with cholangitis. When considered in isolation, an elevated HAV had a high negative predictive value (90%), was more accurate (77%; 95% confidence interval 64-87%) than Charcot's triad (73%; 60-83%), and had similar accuracy compared to 2018 Tokyo Guidelines (79%; 66-88%). Substitution of conventional imaging criteria with elevated HAV in the 2018 Tokyo Guidelines yielded the highest overall accuracy of 84% (72-92%).
Conclusion: HAV is elevated in the majority of patients with cholangitis. Substitution of an elevated HAV for conventional sonographic criteria is more accurate than existing clinical criteria in identifying patients with cholangitis.
Keywords: Biliary duct dilation; Charcot triad; Cholangitis; Hepatic arterial buffer response; Hepatic artery velocity; Liver; Tokyo guidelines; Ultrasound.