Predictive value of early postoperative hemodynamic parameters of Rex shunt graft for graft thrombosis in children with cavernous transformation of the portal vein.

OBJECTIVE: To investigate the predictive value of early hemodynamic parameters within Rex graft for postoperative graft thrombosis in children with cavernous transformation of the portal vein (CTPV). METHODS: A retrospective analysis was performed on clinical data of 34 children with CTPV undergoing primary Rex shunt at Hunan Children's Hospital between May 2010 and November 2025. Serial ultrasonography was conducted to measure hemodynamic parameters at both ends of the graft. Patients were divided into a non-complication group (Group A, n = 22) and a vascular complication group (Group B, n = 12). Intergroup hemodynamic differences were compared, and receiver operating characteristic (ROC) curves were plotted to determine the optimal predictive cutoff value for graft thrombosis. RESULTS: The median postoperative follow-up duration was 40 months, and vascular complications occurred in 12 patients (35.3%), including 5 graft thrombosis cases, 5 anastomotic stenosis cases and 2 cases of graft compression by local edema. The median time to complication onset was 7 (2, 730) days. Hemodynamic parameters remained stable throughout the first postoperative week in Group A (all P > 0.05). The mesenteric graft end with a mean flow velocity of 56.32 ± 19.51 cm/min and mean flow volume of 394.91 ± 225.83 mL/min maintained graft patency, while markedly decreased velocity indicated high thrombotic risk. ROC analysis showed the area under the curve (AUC) of mesenteric velocity was 0.986 (P < 0.001), with an optimal cutoff value of 26 cm/min, a specificity of 90.9% and a sensitivity of 100%. CONCLUSION: Serial monitoring of early mesenteric hemodynamic parameters of the Rex graft offers favorable predictive performance for graft thrombosis, which facilitates timely clinical intervention and improves pediatric patients' prognosis.