Ischemic preconditioning in myocardial revascularization with intermittent aortic cross-clamping.
BACKGROUND
This study tests the hypothesis that initial brief periods of ischemia can increase the protection obtained by intermittent aortic cross-clamping.


METHODS
In the control group (n = 18), the procedure was performed under intermittent aortic cross-clamping at 32 degrees C. Patients in the preconditioned gorup (n = 17) received a stimulus of two 3-minute periods of cross-clamping followed by 2 minutes of reperfusion prior to standard operation. CKMB, troponin 1, adenosine, and lactate were obtained from the great cardiac vein at the onset of cardiopulmonary bypass (CPB), at the end of the first anastomosis, and at the end of CPB.


RESULTS
CKMB and troponin I were slightly higher at the end of CPB in the control group, while there was no difference between adenosine and lactate levels. [table: see text].


CONCLUSIONS
There was no difference between groups in terms of myocardial protection.
Pêgo-Fernandes
P M
PM
Heart Institute (InCor), University of São Paulo Medical School, SP, Brazil. paulopego@incor.usp.br
Jatene
F B
FB
Kwasnicka
K
K
Hueb
A C
AC
Moreira
L F
LF
Gentil
A F
AF
Stolf
N A
NA
Oliveira
S A
SA
D000241:Adenosine / Q000097:blood; D001011:Aorta / Q000601:surgery*; D006328:Cardiac Catheterization; D002315:Cardiopulmonary Bypass; D006324:Heart Arrest, Induced; D006333:Heart Failure / Q000097:blood / Q000601:surgery*; D006801:Humans; D019157:Ischemic Preconditioning, Myocardial; D019344:Lactic Acid / Q000097:blood; D009204:Myocardial Revascularization; D011446:Prospective Studies; D013997:Time Factors; D019210:Troponin I / Q000097:blood
D019210:Troponin I; D019344:Lactic Acid; D000241:Adenosine