Milrinone administered before ischemia or just after reperfusion, attenuates myocardial stunning in anesthetized swine.
OBJECTIVE
We assessed the dose or timing effect of milrinone administered against myocardial stunning in 37 anesthetized open-chest swine.


METHODS
All swine were subjected to 12-min ischemia followed by reperfusion to produce myocardial stunning. Group A (n = 12) received saline in place of milrinone both before and after ischemia. Group B (n = 9) and C (n = 9) received intravenous milrinone at a rate of 5 microg/kg/min for 10 min followed by 0.5 microg/kg/min for 10 min and 10 microg/kg/min for 10 min followed by 1 microg/kg/min for 10 min, respectively, until 30 min before coronary occlusion. Group D (n = 7) received the same dose of milrinone as group B starting 1 min after reperfusion. Myocardial contractility was assessed by percentage segment shortening (%SS).


RESULTS
Five swine in group A and two swine in groups B and C each had ventricular fibrillation or tachycardia after reperfusion, and were thus excluded from further analysis. The percentage changes of %SS from the baseline 90 min after reperfusion in groups B, C, and D were 78 +/- 9%, 82 +/- 13%, and 79 +/- 7%, respectively, which were significantly higher than those in group A (43 +/- 13%).


CONCLUSIONS
We conclude that milrinone administered before ischemia or just after reperfusion attenuates myocardial stunning.
Use
Tadasuke
T
Department of Anesthesiology, Nagasaki University School of Medicine, 1-7-1 Sakamoto, Nagasaki, Japan. makita@net.nagasaki-u.ac.jp
Makita
Tetsuji
T
Ureshino
Hiroyuki
H
Cho
Sungsam
S
Yoshitomi
Osamu
O
Akiyama
Daiji
D
Oshibuchi
Motoko
M
Hara
Tetsuya
T
Sumikawa
Koji
K
D000758:Anesthesia; D000818:Animals; D002316:Cardiotonic Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D005260:Female; D008297:Male; D020105:Milrinone / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D009200:Myocardial Contraction; D017202:Myocardial Ischemia; D015425:Myocardial Reperfusion; D017682:Myocardial Stunning / Q000517:prevention & control*; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics; D013552:Swine
D002316:Cardiotonic Agents; D010726:Phosphodiesterase Inhibitors; D020105:Milrinone