Improved cardiac preservation by the addition of nitroglycerine to colloid-free University of Wisconsin solution (MUW)

Background: This study examines whether the addition of nitroglycerine, a k nown coronary vasodilator and nitric oxide donor, to colloid-free Universit y of Wisconsin solution will improve and extend cardiac preservation. Methods: Rat hearts were flushed and stored in colloid-free University of W isconsin solution with or without the addition of nitroglycerine for 12, 16 or 20 hours at 0 degrees C before heterotopic transplantation with an indw elling externalized intraventricular balloon-tipped catheter. One and 7 day s after transplantation of the heart the catheter was connected to a pressu re transducer and quantitative functional studies were performed. Results: After 12 hours preservation with nitroglycerine in colloid-free Un iversity of Wisconsin solution 6/6 grafts continued to beat for 7 days comp ared to 3/6 without nitroglycerine. After 16 hours preservation the additio n of nitroglycerine 5/7 hearts continued to beat for 7 days compared to 0/6 without nitroglycerine (p < .05). Only 1/6 hearts beat for 7 days after 20 hours preservation with nitroglycerine. On Days 1 and 7, the left ventricu lar developed pressure (LVDP), contractility (max dP/dt) and rate of relaxa tion (peak -dP/dt) of 12 hour preserved hearts was better (p < .05) when ni troglycerine was present. The function of hearts preserved with the additio n of nitroglycerine was similar after 12 and 16 hours preservation. Conclusion: Nitroglycerine is a valuable additive to colloid-free Universit y of Wisconsin solution, extending effective preservation of the rat heart to 16 hours and significantly improving left ventricular function after 12 and 16 hours preservation. The addition of nitroglycerine, however, did not extend preservation to 20 hours.