Neil U. Lall MD, Presenter: Nothing to Disclose

Edward I. Bluth MD, Abstract Co-Author: Nothing to Disclose

Charles Sternbergh, Abstract Co-Author: Nothing to Disclose

Endovascular stenting has been shown to be a safe and effective treatment for hepatic artery stenosis post liver transplant (HASPLT). To date, no detailed evaluation has been completed of the ultrasound (US) changes after stenting. The aim of this study is to improve effective monitoring of these patients by delineating expected postoperative findings.

Ten patients who underwent endovascular stenting for HASPLT at our institution were followed with serial US examinations beginning within 2 days of stent placement (average 1.1 days). Follow up examinations (average follow up 201 days, 5.4 exams) were analyzed and compared to pre-procedure examinations to evaluate changes in the peak systolic velocity (PSV), resistive index (RI), and tardus-parvus waveforms (TPW). This data was used to determine expected post-procedure values for these measurements as well as the expected time course of change in the values.

Of the ten patients, two demonstrated residual HASPLT and two demonstrated resolution followed by restenosis. Pre-procedure, the average RI of the ten patients was 0.40 (range 0.25-0.52), which increased on all patients on the first follow-up exam, improving to 0.62 with a range of 0.4-0.77 (p<0.05). All patients had TPW pre-procedure. TPW resolution was associated with successful outcome, resolving to a normal waveform an average of 1.3 days post-procedure. TPW resolution was significantly delayed in the two patients who did have recurrent stenosis at 22.5 days (p<0.0001), and TPW persisted in the two patients with residual stenosis. Additionally, lower PSV was associated with successful outcome (near statistical significance, p=0.059), noting an average 155cm/s by 5.75 days post-procedure (from 296cm/s).

Ultrasound is a convenient and useful modality to follow stents in HASPLT. Key findings to expect are resolution of TPW and average increase of RI by 0.22 during the first 2 days post-procedure. An additional finding of likely importance is lowering of PSV to near 155 cm/s. Failure to see such findings should alert the physician that the intervention may have been unsuccessful and careful monitoring may be necessary.

This is the first series to document the sonographic findings after hepatic artery stenting in liver transplant patients to advise others how to follow such patients with ultrasound.

Lall, N, Bluth, E, Sternbergh, C, Ultrasound Findings Following Endovascular Stent Deployment in Transplant Liver Hepatic Artery Stenosis.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034539.html