Use of Doppler sonography for revealing hepatic artery stenosis in liver transplant recipients.

Abstract

The goal of our study was to evaluate the use of duplex Doppler sonography for revealing hepatic artery stenosis (HAS) in patients who have undergone liver transplantation. Forty-six patients with spectral Doppler waveforms obtained from the hepatic artery and with subsequent arteriography were reviewed retrospectively. Arterial waveforms, resistive indexes (RIs), and systolic acceleration times (SATs) were evaluated by one reviewer who was unaware of the arteriographic findings. The mean interval between the two examinations was 2.8 days. Arteriograms that revealed a stenosis of greater than 50% were classified as abnormal. Of the 46 patients, 21 (46%) had a significant stenosis. Patients who had HAS had significantly (p < .05) prolonged SATs (0.08 +/- 0.03 sec versus 0.06 +/- 0.02 sec) and reduced RIs (0.49 +/- 0.05 versus 0.66 +/- 0.05) compared with patients who did not have HAS. Optimal thresholds for HAS detection were RIs less than 0.55 and SATs greater than 0.08 sec. HAS was found in 14 of 15 patients who had both abnormal RIs and SATs. Of the remaining 31 patients, 12 had abnormal values for RI or SAT. Of these 12 patients, three had HAS. Thus, 19 patients had normal RIs and SATs; however, four of these patients were found to have an arterial stenosis. In our 46 patients, abnormal values for both RI and SAT were 67% sensitive and 96% specific for stenosis. When at least one abnormal value was found on Doppler imaging, sensitivity and specificity for stenosis were 81% and 60%, respectively. Duplex Doppler imaging can noninvasively reveal HAS. Abnormal values for both RI and SAT proved to be a more accurate predictor of stenosis than either RI or SAT as independent parameters.