Comparison of UW solution and St. Thomas' solution in the rat: importance of potassium concentration.
BACKGROUND
University of Wisconsin solution (UW) is in limited clinical use for heart transplantation, but there are doubts about its efficacy and concerns about the effect of its high K+ concentration on endothelium. St. Thomas' solution with or without aspartate is widely used and is of proven efficacy.


METHODS
Using a modified (starch-free) variant of UW (MUW) we studied: (1) recovery of function with UW compared with aspartate-containing St. Thomas' solution; (2) effect of elevation of K+ in St. Thomas' solution to the level in UW; and (3) effect of reduction of K+ in UW and addition of Ca2+ or aspartate. Isolated rat hearts underwent 7 hours of arrest at 1 degrees C using MUW with or without 20 mmol/L aspartate or using aspartate-containing St. Thomas' solution.


RESULTS
Functional recovery with MUW (51.8% +/- 2.5%) was superior to that with aspartate-containing St. Thomas' solution (37.1% +/- 4.3%; p < 0.01). Addition of aspartate to MUW had no effect. During 6 hours of arrest, lowering the K+ in MUW from 125 mmol/L to 20 mmol/L reduced functional recovery from 59.9% +/- 4.2% to 42.3% +/- 4.3% (p < 0.01). The addition of 1 mmol/L Ca2+ had no effect. Elevation of K+ in St. Thomas' solution produced more rapid arrest but no improvement in recovery.


CONCLUSIONS
The protective effect of starch-free UW is greater (+13%) than that of aspartate-enriched St. Thomas' solution. Reduction of K+ in UW to lessen possible deleterious effects would decrease its protective effect by about 30% to a level comparable with that of St. Thomas' solution.
Rosenfeldt
F L
FL
Baker Medical Research Institute, Alfred Hospital, Melbourne, Victoria, Australia.
Conyers
R A
RA
Jablonski
P
P
Langley
L
L
Richards
S M
SM
Self
G
G
Marshall
V
V
D000818:Animals; D001224:Aspartic Acid / Q000032:analysis; D001639:Bicarbonates / Q000737:chemistry / Q000494:pharmacology; D002118:Calcium / Q000032:analysis; D002122:Calcium Chloride / Q000737:chemistry / Q000494:pharmacology; D002314:Cardioplegic Solutions / Q000737:chemistry* / Q000494:pharmacology; D003326:Coronary Circulation; D006321:Heart / Q000187:drug effects; D006324:Heart Arrest, Induced; D066298:In Vitro Techniques; D008274:Magnesium / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D019188:Organ Preservation Solutions; D011188:Potassium / Q000032:analysis*; D011189:Potassium Chloride / Q000737:chemistry / Q000494:pharmacology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride / Q000737:chemistry / Q000494:pharmacology; D012996:Solutions / Q000737:chemistry* / Q000494:pharmacology; D018709:Statistics, Nonparametric
D001639:Bicarbonates; D002314:Cardioplegic Solutions; D019188:Organ Preservation Solutions; D012996:Solutions; C041711:St. Thomas' Hospital cardioplegic solution; C071285:hydroxyethyl starch-free University of Wisconsin solution; D001224:Aspartic Acid; D012965:Sodium Chloride; D011189:Potassium Chloride; D008274:Magnesium; D002122:Calcium Chloride; D011188:Potassium; D002118:Calcium