title: Association between portal vein thrombosis and survival of liver transplant recipients: a systematic review and meta-analysis of observational studies.
abstract: OBJECTIVE
  Portal vein thrombosis (PVT) increases the technical complexity of liver transplantation (LT). This systematic review and meta-analysis aim to analyze the association of pre-LT PVT with the overall survival after LT.
  
  
  METHODS
  PubMed, EMBASE, and Cochrane library databases were used to search for papers related to the association between pre-LT PVT and survival of LT recipients. The differences in the survival rates between the LT recipients with and without pre-LT PVT were expressed as odds ratios (ORs) with 95% confidence intervals (CIs).
  
  
  RESULTS
  Twenty-seven papers were included. Overall meta-analysis showed that the total LT recipients with pre-LT PVT had a significantly lower 1-year survival rate than those without pre-LT PVT (OR=0.733, 95%CI=0.621-0.865; P=0.0002). But no statistically significant difference was observed in the in-hospital (OR=0.713, 95%CI=0.343-1.482; P=0.365), 1-month (OR=0.679, 95%CI=0.345-1.333; P=0.261), or 5-year survival rate (OR=0.788, 95%CI=0.587-1.058; P=0.113). Additionally, the 1-year survival rate was significantly lower in the LT recipients with complete PVT than in those without PVT (OR=0.503, 95%CI=0.295-0.858; P=0.012). However, no statistically significant difference in the 1-year survival rate between them was observed in the meta-analysis of high-quality studies (OR=0.899, 95%CI=0.657-1.230; P=0.505) or that of studies in which LT was performed after 2000 (OR=0.783, 95%CI=0.566-1.083; P=0.140).
  
  
  CONCLUSIONS
  Pre-LT PVT, especially complete PVT, decreased the 1-year survival rate after LT. However, the detrimental effect of pre-LT PVT on the survival of LT recipients became inconclusive in high-quality studies. Additionally, further well-designed cohort studies should validate the association in patients undergoing LT during the latter years.
authors.affiliation: Liver Cirrhosis Study Group, Department of Gastroenterology, General Hospital of Shenyang Military Area, Shenyang; Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, China.
authors.forename: Xingshun
authors.initials: X
authors.lastname: Qi
authors.affiliation: Liver Cirrhosis Study Group, Department of Gastroenterology, General Hospital of Shenyang Military Area, Shenyang, China.
authors.forename: Junna
authors.initials: J
authors.lastname: Dai
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University; Department of Emergency, Shaanxi Provincial Peoples' Hospital, Xi'an, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Jia
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an; Department of Digestive Diseases, Sanmenxia Central Hospital, Henan University of Science and Technology, Xiaoshan Road, Sanmenxia, China.
authors.forename: Weirong
authors.initials: W
authors.lastname: Ren
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an; Department of Gastroenterology, Songgang People's Hospital, Songgang, Shenzhen, China.
authors.forename: Man
authors.initials: M
authors.lastname: Yang
authors.affiliation: Liver Cirrhosis Study Group, Department of Gastroenterology, General Hospital of Shenyang Military Area, Shenyang, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Li
authors.affiliation: Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, China.
authors.forename: Daiming
authors.initials: D
authors.lastname: Fan
authors.affiliation: Liver Cirrhosis Study Group, Department of Gastroenterology, General Hospital of Shenyang Military Area, Shenyang, China. guo_xiao_zhong@126.com.
authors.forename: Xiaozhong
authors.initials: X
authors.lastname: Guo
mesh_terms: D058625:End Stage Liver Disease / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D016031:Liver Transplantation / Q000009:adverse effects / Q000401:mortality; D064887:Observational Studies as Topic; D016017:Odds Ratio; D011169:Portal Vein / Q000601:surgery*; D011183:Postoperative Complications / Q000401:mortality; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D020246:Venous Thrombosis / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*