Conduit type is associated with distinct fibrin-mediated coagulation trajectories following lower extremity bypass

Abstract

Objective

Prosthetic and autogenous vein conduits used in lower extremity bypass differ in biologic composition and thrombogenic potential, but their influence on postoperative coagulation remains poorly understood. Postoperative antithrombotic strategies following bypass remain largely empiric. We aimed to determine whether the choice of conduit is associated with distinct longitudinal postoperative coagulation trajectories that may inform conduit-specific antithrombotic strategies.

Methods

This single-center prospective observational study evaluated patients undergoing lower extremity bypass with serial perioperative thromboelastography with platelet mapping assessment and stratified according to conduit type: prosthetic or autogenous vein conduit. Longitudinal coagulation trajectories were analyzed using linear mixed-effects models with random intercepts for patients. Fixed effects included postoperative time point, conduit type, antiplatelet therapy, anticoagulation regimen, and time-by-conduit interaction terms.

Results

A total of 338 longitudinal thromboelastography with platelet mapping measurements were obtained from 81 patients undergoing lower extremity bypass, including 59 (72.8%) receiving prosthetic conduit and 22 (27.2%) receiving autogenous vein conduit. Adjusted mixed-effects modeling demonstrated a significant time-by-conduit interaction for citrated functional fibrinogen maximum amplitude (P = .048), indicating differing postoperative fibrin-mediated clot strength trajectories according to conduit type. Prosthetic conduit recipients demonstrated an earlier postoperative rise in citrated functional fibrinogen maximum amplitude, peaking around postoperative day 4, whereas vein conduit recipients demonstrated a later peak around postoperative day 5.

Conclusions

Conduit type was associated with distinct postoperative coagulation trajectories following lower extremity bypass, with the principal conduit-associated differences observed in fibrin-mediated clot-strength trajectories. These findings should be considered hypothesis generating and suggest that postoperative coagulation physiology may differ according to conduit type and support further investigation into whether conduit-specific coagulation phenotypes can inform individualized antithrombotic strategies.

Clinical relevance

Postoperative antithrombotic management following lower extremity bypass remains largely empirical despite well-recognized differences in thrombogenicity between prosthetic and autogenous vein conduits. In this prospective longitudinal study, conduit type was associated with distinct fibrin-mediated coagulation trajectories during early postoperative recovery, with prosthetic conduit recipients demonstrating an earlier rise in citrated functional fibrinogen maximum amplitude than autogenous vein conduit recipients. These findings suggest that postoperative coagulation physiology may differ according to conduit type and raise the possibility that the relative contributions of platelet- and fibrin-mediated coagulation differ across conduit types. They provide a biologic rationale for future studies evaluating whether conduit-specific coagulation phenotypes identified by serial thromboelastography with platelet mapping are associated with graft-related outcomes and can inform individualized antithrombotic strategies.