2,3-Butanedione monoxime cardioplegia: advantages over hyperkalemia in blood-perfused isolated hearts.
BACKGROUND
2,3-Butanedione monoxime (BDM) has been shown to possess cardioprotective properties related to the inhibition of cross-bridge force development, the reduction of myofilament Ca2+ sensitivity, and the attenuation of intracellular Ca2+ transients. This study tested the hypothesis that cardiac arrest achieved with BDM would be as effective as that achieved with St. Thomas' solution (StT).


METHODS
Isolated rabbit hearts, studied on a blood-perfused Langendorff column, underwent 1 hour of ischemia (37 degrees C) and 30 minutes of reperfusion. Cardioplegia was administered every 20 minutes in the form of (1) Krebs-Henseleit solution only (control), (2) 20 mmol/L of BDM, or (3) StT. Recovery of developed pressure, atrioventricular activation times, and tissue water content were measured.


RESULTS
Recovery of developed pressure for the control, BDM, and StT groups was 44%+/-3% (p<0.05 versus BDM and StT), 57%+/-5%, and 62%+/-4%, respectively. Atrioventricular activation times were significantly prolonged in the control group (42+/-15 ms, p = 0.042) and the StT group (26+/-9 ms, p = 0.034), but not in the BDM group (14+/-8 ms). Tissue water content after reperfusion was 80%+/-0.4%, 80%+/-0.2%, and 76%+/-1.0% (p<0.05 versus control) in the control, StT, and BDM groups, respectively.


CONCLUSIONS
2,3-Butanedione monoxime was as effective as StT in protecting the myocardium. Unlike StT, BDM ameliorated myocardial edema and atrioventricular conduction delay after reperfusion.
Jayawant
A M
AM
Milton S. Hershey Medical Center, Pennsylvania State University, Hershey 17033, USA.
Stephenson
E R
ER
Damiano
R J
RJ
D000818:Animals; D001639:Bicarbonates; D002122:Calcium Chloride; D002314:Cardioplegic Solutions; D003326:Coronary Circulation; D003931:Diacetyl / Q000031:analogs & derivatives*; D005947:Glucose; D006321:Heart / Q000503:physiopathology; D006324:Heart Arrest, Induced; D066298:In Vitro Techniques; D008274:Magnesium; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism; D011188:Potassium / Q000097:blood; D011189:Potassium Chloride; D011817:Rabbits; D012965:Sodium Chloride; D014325:Tromethamine
D001639:Bicarbonates; D002314:Cardioplegic Solutions; C074097:Krebs-Henseleit solution; C041711:St. Thomas' Hospital cardioplegic solution; D014325:Tromethamine; C004717:diacetylmonoxime; D012965:Sodium Chloride; D011189:Potassium Chloride; D008274:Magnesium; D005947:Glucose; D003931:Diacetyl; D002122:Calcium Chloride; D011188:Potassium