Performance of Hepatic Artery Velocity in Evaluation of Causes of Markedly Elevated Liver Tests

The purpose of this study was to assess the utility of peak systolic proper hepatic artery velocity (HAV) in differentiating causes of severely elevated liver function tests. HAV, hepatic artery resistive index and portal vein velocity of 41 patients with severely elevated liver function tests were evaluated. In 19 patients (46%), the causes were structural (e.g., cholecystitis, cholangitis), whereas in 22 patients (54%) the causes were non-structural (e.g., rhabdomyolysis, drug-induced liver injury). The average HAV for structural causes was 138 ± 68cm/s, and for non-structural causes, 65 ± 29cm/s (p < 0.0001). An HAV >100cm/s was correlated with structural causes (p = 0.0001). With respect to diagnostic performance, this threshold was 79% sensitive and 86% specific, with a high positive likelihood ratio (5.8) and low negative likelihood ratio (0.24). The resistive index and portal vein velocity were not statistically different. In patients with severely elevated liver function tests, an HAV >100cm/s can help distinguish structural from non-structural causes, which may guide management while awaiting definitive laboratory tests.