Background: Prior studies suggest that patients’ body composition changes following transjugular intrahepatic portosystemic shunt (TIPS) implantation, potentially influencing complications and survival. Method: A prototype artificial intelligence (AI)-based, automated computed tomography (CT) body composition analysis tool was used to assess body composition imaging parameters in pre- and postinterventional scans of TIPS patients: visceral (VAT) and subcutaneous adipose tissue (SAT) areas, psoas muscle area (PMA), and total abdominal muscle area (TAMA). Sarcopenia was defined as a lumbar skeletal muscle index (LSMI) ≤ 38.5 cm²/m² in women and ≤52.4 cm²/m² in men. We analyzed longitudinal changes in body composition and investigated the impact of sarcopenia at TIPS implantation on the risk of TIPS thrombosis, hepatic encephalopathy, complications, and death using Cox regression models. Results: No clear trend emerged regarding changes in body composition parameters during postinterventional follow-up. Sarcopenia at TIPS implantation increased the instantaneous risk of postinterventional complications (hazard ratio (HR) 1.67; 95% confidence interval (CI) 0.95–2.93), development of hepatic encephalopathy (HR 1.65; 0.81–3.33), as well as the risk of dying within one year (HR 1.39; 0.66–2.92). Conclusions: CT body composition analysis may help in identifying high-risk patients undergoing TIPS implantation. Sarcopenia was associated with increased mortality and a higher incidence of postinterventional complications, particularly hepatic encephalopathy.