Abstract: Objective To investigate the influencing factors of inferior vena cava (IVC) thrombosis in patients with type Ⅱ Budd-Chiari syndrome(BCS) and observe the curative effect of interventional therapy. Methods From January 2005 to January 2020, 106 patients with type Ⅱ BCS successfully treated by interventional therapy in our hospital were analyzed, including 66 males and 40 females, aged (45.4±10.4) years. They were divided into groups based on the presence or absence of thrombus. The treatment encompassed urokinase thrombolysis via catheter, balloon dilatation or stent implantation. The clinical data of patients with or without type Ⅱ BCS were analyzed by univariate and multivariate analysis. The patients were followed up and the effectiveness of the interventional therapy was assessed by comparing the patients conditions before and after interventional. Results Out of the 106 patients with type Ⅱ BCS, 17 cases were complicated by thrombus formation (Group A), while the remaining 89 cases exhibited no such complication(Group B). The median age in Group A [50 (43, 67) years old] was significantly higher than that of Group B [44 (37, 62) years old, P<0.05]. Abdominal distension and ascites in Group A were 10 cases (58.8%) and 9 cases (52.9%) respectively, which were significantly higher than those in Group B[29 cases (32.6%) and 21 cases (23.6%) respectively, P<0.05]. The median levels of WBC, ALT, AST, TBil, Alb, PTA and fibrinogen in Group A were 5.7 (4.4, 7.1) ×10⁹/L, 77 (52, 146) U/L, 74 (60, 135) U/L, 36.4 (23.4, 78.6) μmol/L, 34 (28, 37) g/L, 66 (63, 70) % and 5.2 (3.4, 7.0) g/L respectively. When compared with those in Group B[4.3 (3.0, 6.5) × 10⁹/L, 24 (15, 80) U/L, 31 (18, 76) U/L, 25.2 (16.8, 44.0) mol/L, 39 (35, 46) g/L, 75(70, 78) % and 2.9 (2.6, 6.0) g/L], The differences were statistically significant(P<0.05). The Child-Pugh scores of Group A and Group B were 7.3 (6.0, 9.2) points and 6.4 (4.8, 7.0) points respectively, the difference being statistically significant (P<0.05). Significant factors(P<0.05) were further subjected to multivariate analysis, revealing age, WBC count, TBil and Alb as statistically distinct from other factors(P<0.05), thus deeming them as independent influencers of type Ⅱ BCS complicated by thrombosis. Among the 17 patients with type Ⅱ BCS complicated by thrombus, 14 cases experienced complete dissolution, 3 showed partial dissolution, and in all patients, unobstructed IVC blood flow was achieved. The pressure difference between the IVC and right atrium significantly decreased from the preoperative measure[19 (14, 27) cmH₂O] to the postoperative measure[5 (3, 8) cmH₂O, P<0.05]. In a follow-up period ranging from 1 to 40 months, there was one death; two cases of IVC restenosis were successfully managed with additional balloon dilatation again. Conclusion Age, WBC and TBil serve as independent risk factors for thrombosis in patients with type Ⅱ BCS, while Alb is a protective factor. The recurrence rate for thrombosis in patients with type Ⅱ BCS who undergo interventional therapy is low, indicating a satisfactory long-term therapeutic outcome.

Key words: Budd-Chiari syndrome, Inferior vena cava, Thrombus, Multivariate analysis