Clinical Impact of Spontaneous Portosystemic Shunts in Liver Transplantation: A Comprehensive Assessment Through Total Shunt Area Measurement

Abstract

Background. The impact of spontaneous portosystemic shunts (SPSSs) on natural history of cirrhotic patients was recently evaluated through the measurement of total shunt area (TSA), a novel tool that allows a comprehensive assessment of SPSSs extension, identifying a direct correlation of higher TSA with lower patient survival. The role of SPSSs in liver transplant (LT) is still debated: we sought to investigate the clinical impact of TSA on the development of early allograft dysfunction (EAD), acute kidney injury (AKI), postoperative complications, and graft and patient survival following LT. Methods. Preoperative imaging of 346 cirrhotic patients undergoing primary LT between 2015 and 2020 were retrospectively revised, recording the size and anatomy of each SPSS to calculate TSA. The impact of TSA and selected patient and donor characteristics on the development of EAD, AKI, and clinically relevant complications was evaluated through univariate and multivariate logistic regression, whereas their effect on graft and patient survival was investigated through Cox regression analysis. Results. A TSA exceeding 78.54 mm 2 resulted as an independent risk factor for the development of EAD (odds ratio [OR]: 2.327; P = 0.003), grade 3 AKI (OR: 2.093; P = 0.041), and clinically relevant complications (OR: 1.962; P = 0.015). Moreover, higher TSA was significantly related to early graft and patient survivals, emerging as an independent risk factor for 12-mo graft loss (hazard ratio: 3.877; P = 0.007) and patient death (hazard ratio: 2.682; P = 0.018). Conclusions. Higher TSA emerged as a significant risk factor for worse postoperative outcomes following LT, supporting the need for careful hemodynamic assessment and management of patients presenting multiple/larger shunts.

What Are Risk Factors for Graft Loss in Patients Who Underwent Simultaneous Splenectomy During Living-donor Liver Transplantation?

“…This presents a potential hazard of graft hypoperfusion, portal vein thrombosis, and impaired liver regeneration, attributable to the so-called steal phenomenon. 42 Given this context, we have advocated for a systematic approach to intraoperative/perioperative ligation of SPSSs to optimize portal flow to the liver allograft, thereby averting graft hypoperfusion and loss. 14 Tailoring portal hemodynamics becomes particularly crucial when managing a partial allograft with diminished vascular capacity, as this may impede SPSSs detention and exacerbate the portal steal phenomenon.…”

“…Ensuring a thorough assessment of graft perfusion is paramount when confronted with this “short blanket.” The current literature strongly advocates for comprehensive intraoperative flow-pressure monitoring to customize portal flow to the graft volume. 31,43 Centonze et al 42 have identified a higher total shunt area (measured in mm 3 ) as a noteworthy risk factor for unfavorable post-LT outcomes. This underscores the necessity for meticulous hemodynamic assessment and management in patients with multiple or larger shunts.…”

From large-for-size to large-for-flow: A paradigm shift in liver transplantation

“…[26] Second, pre-LT CTscan of the recipient allows for identifying surrogates of LPF, such as PVT, [27,28] portal vein caliber, [29] and PSS. Besides, pre-LT evaluation by CT-scan [30] or 4D-MRI [31] is a promising perspective to anticipate the surgical strategy for portal flow modulation by providing a precise anatomic and hemodynamic mapping of PSS. Second, in the case of high GRWR and potential LPF, recipients with portal hypertension, ascites, or PSS should be preferentially selected as they present the possibility of portal inflow modulation.…”

Temporary Portocaval Shunt Provides Superior Intra-operative Hemodynamics and Reduces Blood Loss and Duration of Surgery in Live Donor Liver Transplantation

“…In the presence of large (>10 mm) shunts without PVT, the recipient hepatectomy becomes technically easier because of attenuated perihepatic collaterals. Also, previous studies have reported the presence of a large shunt as an independent risk factor for clinically relevant complications, grade 3 acute kidney injury (AKI), and even the development of early allograft dysfunction (EAD) after liver transplantation (LT) 5 . As the recipients with large shunts can skew the study outcomes, they were excluded.…”