Effects of storage solutions on in vitro vasoreactivity of radial artery conduits.
OBJECTIVE
Surgical preparation of coronary conduits for coronary artery bypass grafting may affect their early and long-term patency; one mechanism may involve endothelial damage. We investigated the effect of 3 commonly used solutions-Ringer's solution, normal saline solution, and heparinized whole blood-on in vitro endothelial and contractile functions of the human radial artery.


METHODS
Radial artery segments were harvested, cut into 3-mm rings, and stored in unoxygenated Ringer's solution, normal saline solution, or heparinized whole blood for 45 minutes. Rings stored in Krebs solution were used as controls. The rings were then mounted and stretched to an optimal resting tension in oxygenated Krebs solution at 37 degrees C. Contraction responses to potassium, norepinephrine, and serotonin and relaxation responses to acetylcholine, verapamil, and nitroprusside were evaluated.


RESULTS
Fifty-six radial artery ring segments from 14 patients (n = 7 rings for each contraction-relaxation curve) were studied. Equilibrated resting tension was 9.6 +/- 0.3 mN (5.9 +/- 0.2 g), and resting internal circumference was 6.4 +/- 0.2 mm. Absolute maximum contraction to potassium was significantly less in rings stored in normal saline solution than in rings stored in control solution (10.7 +/- 0.6 g vs 14.5 +/- 0.6 g, P <.01; 95% confidence intervals, 0.9-6.9). There was no difference in the contraction to norepinephrine (P =.11) and serotonin (P =.25) among the 3 solutions compared with the control solution. Rings stored in heparinized whole blood had significantly greater endothelium-dependent relaxation to acetylcholine (P <.007), whereas those stored in normal saline solution had reduced responses. Endothelium-independent relaxation to verapamil and nitroprusside were similar among the 3 solutions.


CONCLUSIONS
Heparinized whole blood is a better physiologic medium for preservation of radial artery endothelial and contractile functions during storage before grafting.
Chong
W C
WC
Department of Cardiothoracic Surgery, Royal Brompton and Harefield NHS Trust, London, United Kingdom.
Ong
P J
PJ
Hayward
C
C
Moat
N
N
Collins
P
P
D000109:Acetylcholine / Q000494:pharmacology; D001769:Blood; D001026:Coronary Artery Bypass / Q000379:methods; D004353:Drug Evaluation, Preclinical; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007552:Isotonic Solutions / Q000009:adverse effects*; D009599:Nitroprusside / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D019188:Organ Preservation Solutions / Q000009:adverse effects*; D011188:Potassium / Q000494:pharmacology; D017534:Radial Artery / Q000187:drug effects* / Q000502:physiology* / Q000637:transplantation; D000077331:Ringer's Solution; D012701:Serotonin / Q000494:pharmacology; D012965:Sodium Chloride / Q000009:adverse effects*; D013997:Time Factors; D014021:Tissue Preservation / Q000379:methods*; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
D007552:Isotonic Solutions; D019188:Organ Preservation Solutions; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D012701:Serotonin; D012965:Sodium Chloride; D000077331:Ringer's Solution; D014700:Verapamil; D000109:Acetylcholine; D011188:Potassium; D009638:Norepinephrine