HEPATIC ARTERY THROMBOSIS (HAT) IS A DREADFUL COMPLICATION FOR TRANSPLANT SURGEONS, WHAT CAUSES IT?

Abstract

Introduction: Hepatic artery thrombosis (HAT) is a critical complication in liver transplantation, particularly in living donor liver transplantation (LDLT). The risk of graft loss leads to the need for re-transplant and identifying another donor. Identifying risk factors associated with HAT can improve patient outcomes. This study aims to evaluate various risk factors in the incidence of HAT in Living donor liver transplant (LDLT).

Methods: A retrospective analysis using a prospectively kept database was conducted on 500 LDLT cases from March 2019 to Oct 2023. Data were obtained from electronic health records, including demographic details, full clinical data, liver-specific assessments (e.g. CTP grade, MELD Na), and surgical factors (e.g. ischemic times, surgery duration). Hepatic artery thrombosis (HAT) was defined as thrombosis occurring within the first 30 days post-transplant, confirmed by imaging. Statistical tests (chi-square, Mann-Whitney U) analyzed HAT incidence across all available variables. Logistic regression models were used to assess the association between HAT and different risk factors.

Results: By analyzing data of 500 patients (382 males and 118 females; mean age 43.8 years), HAT was recorded in 10 patients (2%) with annual incidences of 1.67%, 2.37%, and 1.99% for the years 2021, 2022, and 2023, respectively. The analysis identified significant associations between HAT and two factors: prolonged recipient surgery duration (p = 0.001) and increased cold ischemia time (p = 0.057). Other factors, including recipient gender (p = 0.707), age (p = 0.611), blood group compatibility (p = 1.000), and anastomotic techniques, donor arterial anatomy and type of reconstruction showed no statistically significant association with HAT. HAT cases exhibited a higher incidence of postoperative complications, including a 17.44-fold increase in mortality risk (95% CI: 4.52-67.28) and a need for re-exploration (p < 0.001).

Conclusion:   Prolonged recipient surgery duration and increased cold ischemia time are significant risk factors associated with hepatic artery thrombosis (HAT) in living donor liver transplantation (LDLT). Although factors like recipient demographics, blood group compatibility, and anastomotic techniques showed no statistical association with HAT, patients who developed HAT faced significantly higher post-operative complications, including increased mortality risk and need for re-exploration. These results suggest that surgical length and ischemic control must be optimized to reduce HAT risk and enhance patient outcomes following LDLT.