Superior Vena Cava Graft for Right Liver and Right Lateral Sector Transplantation

BACKGROUND

The usefulness of cryopreserved superior vena cava (SVC) grafts for venous reconstruction remains to be evaluated in right liver and right lateral sector transplantation.

METHODS

Reconstruction of the hepatic vein was performed when the congested area in the liver graft was significant. A vein graft with a suitable shape and length meeting the demands for the venoplasty was selected, and SVC grafts were used in 20 recipients. Surgical techniques were classified into five types according to the necessity of middle or short hepatic vein reconstruction in the liver graft. Surgical outcomes and vein graft patency were evaluated.

RESULTS

All 20 recipients survived the operation without any complications caused by congestion. Liver functions were well recovered in the early postoperative period. The 1-year primary patency rates of cryopreserved vein grafts used for reconstructed right hepatic veins, inferior right hepatic veins, and middle hepatic vein tributaries were 100%, 94%, and 42%, respectively.

CONCLUSIONS

SVC grafts were feasible for outflow tract reconstruction in right liver and right lateral sector transplantation, although the long-term patency of the grafts for middle hepatic vein reconstruction remains to be evaluated.

Depopulated vena caval homograft: a new venous conduit

OBJECTIVE

Completion of the Fontan procedure is frequently performed by using an extracardiac conduit between the inferior vena cava and the pulmonary artery. Most centers use a polytetrafluoroethylene graft for the extracardiac conduit, and because re-endothelialization is unlikely, anticoagulation is used for a variable period. This study explores the use of an alternate large-caliber venous conduit.

METHODS

The superior vena cava was replaced in 8 minipigs with either a polytetrafluoroethylene interposition graft (2 pigs) or a depopulated (acellular), cryopreserved superior vena caval homograft (6 pigs). After 6 months, the animals were killed, and the grafts were examined for patency and histology, including immunostaining. No anticoagulation was used.

RESULTS

Polytetrafluoroethylene grafts have a cross-sectional luminal narrowing, ranging from 16% to 40%. Histology showed only partial intimal ingrowth, with excessive subendothelial fibrosis and early calcification. In contrast, the depopulated venous homografts showed minimal luminal narrowing, ranging from 2% to 9%. These grafts were completely repopulated by the recipient with an endothelial lining, which stained positively for factor VIII, and a subendothelial region appropriately recellularized by myofibroblasts, which stained positively for smooth muscle actin and procollagen. There was no evidence of an immune response to the venous homografts, as judged by staining for T-cell surface antigen, CD4, and CD8. Thrombus was not seen in any of the grafts.

CONCLUSION

Depopulated, cryopreserved vena caval homografts might be superior conduits for cavopulmonary connection during completion of the Fontan operation by using the extracardiac conduit technique.

Transplantation of the heart and both lungs. I. Historical review

Transplantation of the heart and both lungs is being considered as a clinical possibility in several surgical centres today. This paper reviews the experimental development of surgical techniques in this field. In the 1940s Demikhov in the U.S.S.R. succeeded in developing a technique by which he could carry out cardiopulmonary transplantation without the use of any artificial means of recipient support during the procedure. He obtained survivors for up to six days; late deaths occurred mainly from pulmonary complications. The techniques and results of subsequent workers using hypothermia or pump-oxygenator support are reviewed. Recent work has focused on the problem of the return of spontaneous respiration following denervation of the lungs which, of necessity, occurs during this procedure.