Extended ex vivo myocardial preservation in the beating state using a novel polyethylene glycolated bovine hemoglobin perfusate based solution.
Cardiac preservation for transplantation is generally limited by ischemic hypothermic storage of 4-6 hours. Earlier studies in the authors' laboratory have demonstrated that hypothermic perfusion preservation using a novel oxygen carrying hemoglobin solution may extend preservation times to 8 hours and decrease ischemic injury. The purpose of this study was to compare extended cardiac function after 12 and 24 hours of continuous hypothermic perfusion with a polyethylene glycolated bovine hemoglobin perfusate (PEG-Hb) solution to the clinical standard of hypothermic ischemic preservation. The hearts of 54 anesthetized and intubated New Zealand White rabbits were harvested after cold cardioplegic arrest. Group I (n = 12) hearts were perfused with a PEG-Hb solution at 20 degrees C and 30 mm Hg for 24 hours. Group II (n = 10) hearts were preserved similarly with PEG-Hb for 12 hours. Group III (n = 12) hearts were preserved for 8 hours with PEG-Hb; Group IV (n = 10) were preserved by cold ischemic storage for 4 hours at 4 degrees C; and Group V (n = 10) were tested after fresh extirpation. Left ventricular (LV) function was measured in the nonworking state at 15 minute, 1 hour, and 2 hour intervals after transfer to a standard crystalloid Langendorff circuit. Developed LV pressure at 0.5 ml LV volume was superior in Group II at early time points, yet it was similar in all preserved groups at 2 hours. +dP/dt(max) at 0.5 ml LV volume was consistent at all time points and greater in PEG-Hb preserved groups compared with Group V. -dP/dt(max) at 0.5 ml LV volume was significantly greater in Groups II and III compared with Group V initially (p < 0.05), but all were similar at the end of testing. Continuous perfusion preservation of rabbit hearts for time increments up to 24 hours with this novel PEG-Hb solution at 30 mm Hg and 20 degrees C yields LV function that is similar to 4 hours of ischemic hypothermic storage. Extended cardiac perfusion preservation with this PEG-Hb solution deserves further investigation in large animal transplant models.
Jones
Blanding U
BU
Division of Cardiothoracic Surgery, Department of Pharmacology, University of California, Irvine, Medical Center, Orange, California 92868, USA.
Serna
Dan L
DL
Smulowitz
Peter
P
Connolly
Peter
P
Farber
Adam
A
Beckham
Gerry
G
Shrivastava
Vineet
V
Kahwaji
Chad
C
Steward
Earl
E
Purdy
Ralph E
RE
Parker
W Lane
WL
Ages
Berend
B
Milliken
Jeffrey C
JC
D000818:Animals; D002417:Cattle; D006321:Heart / Q000502:physiology; D006454:Hemoglobins; D066298:In Vitro Techniques; D008297:Male; D009926:Organ Preservation / Q000379:methods*; D019188:Organ Preservation Solutions; D010477:Perfusion; D011092:Polyethylene Glycols; D011817:Rabbits; D013997:Time Factors; D016277:Ventricular Function, Left
D006454:Hemoglobins; D019188:Organ Preservation Solutions; C109960:PEG-hemoglobin; D011092:Polyethylene Glycols