Splenic Artery Embolism in Liver Transplant Patients: A Single-Center Experience.

Background: Hypersplenism, portal hypertension, and ascites have been seen after liver transplants. Patients are usually treated medically with refractory patients potentially undergoing splenectomy. Splenic artery embolism (SAE) is an alternative that can be performed to limit the surgical intervention that may have the benefit of improving portal hypertension. Few studies have studied the effect on main portal vein (MPV) velocities and hepatic artery resistive indices (HARIs) which may be beneficial as markers of portal hypertension.

Purpose: This study aims to evaluate the efficacy and safety of interventional radiology (IR)-guided SAE for the management of portal hypertension in patients who have had liver transplants.

Methods: A retrospective analysis was conducted on liver transplant patients who had undergone IR-guided SAE post-transplant at a single tertiary transplant center from 2012 to 2022. The primary outcome of intervention efficacy was quantified by peak HARIs and MPV velocities. Ultrasound with Doppler obtained before and after the intervention was reviewed for these parameters. Secondary outcomes included adverse events at the time of the procedure and within one year of the procedure, the need for splenectomy, and spleen size.

Results: Twenty-eight patients met the criteria for inclusion. The mean age of patients was 52.5 years (21-71 years) and the time after transplant was 149.5 days (2-1588 days). About 96.4% of SAEs were technically successful (n=27). Twenty-one patients had MPV velocities available, and 24 had peak HARIs available. In these patients, HARIs decreased by an average of 0.063 (95% CI 0.014-0.112) after SAE. MPV velocity decreased by an average of 47.2 cm/s (95% CI 27.3-67.1) after SAE. About 10.4% of patients (n=3) developed a procedure-related complication, all of which were femoral access site aneurysms. No (0) patients suffered from bleeding, infections, or abscesses after the procedure. About 10.7% of patients (n=3) required splenectomy after SAE: one splenectomy was due to technical failure and two were due to refractory symptoms.

Conclusion: We performed one of the first analyses on MPV and RI and showed that our patients saw an improvement post-embolization with a theoretical improvement in portal hypertension. The complication rate and risk of infection seem to be acceptable risks, making SAE a feasible option for management.