Modified technique of abdominal heart transplantation in the rat.
BACKGROUND
A rapid, reproducible screening model is essential for evaluation of novel preservation regimens. This study describes a modification of the abdominal rat heart transplantation model reducing anastomosis time and allowing quantitative assessment for 7 days.


METHODS
Hearts, obtained from inbred Dark Agouti rats, were arrested and stored in cold colloid-free University of Wisconsin solution until transplantation. The Dark Agouti recipient underwent a left nephrectomy. The donor left common carotid artery was anastomosed to the recipient left renal artery with a "sleeve" anastomosis. The "cuffed" donor left pulmonary artery was inserted into the left renal vein. Study 1 examined continuing viability by daily palpation and morphologic study by examination of hematoxylin and eosin-stained sections on days 4 or 90. Study 2 examined quantitative assessment of cardiac function in the anesthetized recipient. The model was further modified by introducing an externalized, fluid-filled, balloon-tipped catheter into the left ventricle.


RESULTS
The new technique allowed vascular anastomoses to be completed in 5 to 12 minutes, minimizing rewarming of the graft. Most (25 of 28) grafts beat for 90 days, and 80% of these showed normal structure. There was evidence of myocyte damage or arteriosclerosis in 5 of 25 at 90 days and in 4 of 17 at 4 days. Cardiac function parameters were similar in consecutive runs and did not change between days 1 and 7.


CONCLUSIONS
This abdominal rat heart transplant model is quick and easy to perform, minimizes warm ischemia, and is suitable for both short- and long-term studies. Quantitative parameters, assessed by use of an in situ intraventricular balloon-tipped catheter, are reproducible and maintained for 7 days.
Baxter
K
K
Monash University, Department of Surgery, Monash Medical Centre, Melbourne, Australia. Kirsty.Baxter@med.monash.edu.au
Hao
P M
PM
Howden
B O
BO
Saunder
A
A
Jablonski
P
P
D000818:Animals; D006328:Cardiac Catheterization; D005260:Female; D006085:Graft Survival; D006339:Heart Rate; D016027:Heart Transplantation / Q000379:methods*; D008297:Male; D009206:Myocardium / Q000473:pathology; D009926:Organ Preservation; D051381:Rats; D011919:Rats, Inbred Strains; D016042:Transplantation, Heterotopic / Q000379:methods*; D016277:Ventricular Function, Left