Caution Regarding Short-Term Increases in Ammonia Levels Following Splenic Artery Embolization

Area of Science:

• Interventional Radiology
• Hepatology
• Portal Hypertension Management

Background:

• Hepatic encephalopathy is a complication of portal hypertension.
• The impact of partial splenic embolization (PSE) on ammonia levels in hepatic encephalopathy is not fully understood.
• Portosystemic shunts (PSSs) can influence portal hemodynamics.

Purpose of the Study:

• To investigate the effect of PSE on ammonia levels.
• To identify factors influencing ammonia level changes after PSE.
• To compare outcomes in patients with and without PSSs.

Main Methods:

• Retrospective study of 136 patients undergoing PSE for hypersplenism.
• Patients categorized into groups with (PSS+) and without (PSS-) significant PSSs (≥ 8 mm).
• Ammonia levels, biochemical, and imaging data assessed pre- and post-PSE.

Main Results:

• PSE significantly increased ammonia levels overall, despite improved liver function and reduced hepatic venous pressure gradient.
• Higher rates of ammonia increase observed in the PSS (-) group (73.3%) compared to the PSS (+) group (63.0%).
• Specific preprocedural factors identified as determinants for ammonia increase in both groups.

Conclusions:

• Partial splenic embolization carries a significant risk of short-term ammonia level elevation.
• Patients without portosystemic shunts are particularly susceptible to post-PSE ammonia increase.
• Findings emphasize careful patient selection and monitoring after PSE.