Abstract: Objective:To investigate the shortterm therapeutic effect of warfarin in preventing portal vein thrombosis (PVT) after modified laparoscopic splenectomy combined with pericardial devascularization.
Methods The retrospective cohort study was used to analyze the clinical data of 32 patients with cirrhotic portal hypertension who were admitted to the Clinical Medical College of Yangzhou University between January 2014 and August 2014. The characteristics of warfarin and aspirin regimens were introduced to the patients before operation for choosing postoperative therapeutic regimen. Based on the decisions, 17  and 15 patients receiving warfarin regimen and aspirin regimen were divided into the warfarin group and the aspirin group,respectively. All the patients underwent successful modified laparoscopic splenectomy and pericardial devascularization with intraoperative autologous blood salvage.The treatments were as follows: from postoperative day  3, patients in the warfarin group received 2.5 mg of oral warfarin once daily with titration of the dose to maintain a target international normalized ratio (INR) of 2.0-3.0 for 1 year; patients in the aspirin group received 100 mg aspirin enteric coated tablets for 1 year; and both groups received 50 mg of oral dipyridamole three times daily for 3 months and subcutaneous injection of 4 100 U of lowmolecularweight heparin (LMWH) once daily for 5 days. Blood cell analysis, liver function, coagulation function and Doppler ultrasound screening for the occurrence of PVT were performed at the first and third months. Postoperative electronic gastroscopy was performed at 3 months postoperatively for observing the change of the esophageal and gastricfundus varices.The patients were followed up till February 2015. The incidences of PVT and the level of INR at the first week, the first month and the third month after operation were observed. Measurement data with normal distribution were presented as ±s and analyzed by t test, and measurement data with skewed distribution were presented as M(range) and analyzed by the ranksum test. Comparison of the mean INR at different time points between the 2 groups was analyzed by the repeated measures ANOVA. Comparison of count data was analyzed by the Fisher′s Exact Probility.
Results:There were no gastrointestinal hemorrhage or perioperative death in the 2 groups. (1)The overall incidences of PVT  at postoperative week 1 were 9/17 and 6/15 in the warfarin and the aspirin groups, respectively, with no significant difference (P>0.05) . However, the overall incidences of PVT at postoperative month 1 and 3 were 7/17 and 3/17 in the warfarin group, which was significantly different from 12/15 and 12/15 in the aspirin group (P< 0.05). (2)The incidences of main portal vein thrombosis (MPVT) at postoperative week 1 and postoperative month 1 were 5/17 and 6/17 in the warfarin group, 4/15 and 5/15 in the aspirin group, showing no significant difference (P>0.05) . The incidence of MPVT at postoperative month 3 was 3/17 in the warfarin group, which was significantly different from 9/15 in the aspirin group (P<0.05). (3)The INR was changed from 1.30±0.17 before operation to 1.55±0.38 at postoperative month 3 in the warfarin group, and from 1.33±0.14 before operation to 1.21±0.11 at postoperative month 3 in the aspirin group, showing significant difference in the changing trend between the 2 groups (F= 713.908, P<0.05). (4) All the 32 patients were followed up for a median time of 7 months (range, 3-11 months). The results of electronic gastroscopy at postoperative month 3 showed that the esophageal and gastricfundus varices were obviously improved or disappeared.
Conclusion Warfarin in preventing PVT after modified laparoscopic splenectomy combined with pericardial devascularization is safe and feasible, with a good shortterm outcome.