Background: Sequential pancreatic islet transplantation via the portal vein has led to insulin independence in patients with type 1 diabetes. Complications associated with the injection of islets into the portal vein have been reported; therefore, in this study we sought to further characterize changes in portal venous pressure associated with islet infusion.
Methods: Pre- and posttransplant portal venous pressures were recorded in 50 consecutive transplant procedures in 26 patients receiving highly purified, heparinized allogeneic islet preparations via a radiologically placed portal venous cannula. Doppler ultrasound scans of the portal vein were completed within 24 hr of transplantation.
Results: Posttransplant portal vein pressures rose significantly with sequential transplantation (12.4 mm Hg vs. 17.3 mm Hg, P <0.05). Portal pressure change correlated significantly with islet packed cell volume (r =0.66, P <0.001) and also with the number of islets transplanted ( r=0.49, P <0.001). Segmental portal vein thrombosis was radiologically detected after two procedures (4%).
Conclusion: Multiple sequential islet transplants can be safely performed via the portal vein, provided that care is taken with islet purification and attention is paid to portal venous monitoring.