L-arginine supplemented nondiluted blood cardioplegia: a clinical trial.
OBJECTIVE
L-arginine was shown to improve protection of the myocardium during coronary artery bypass graft (CABG) surgery. The objective of the present study was to determine the concentration of L-arginine to obtain the most effective protection of the myocardium during CABG surgery.


METHODS
Seventy-five patients undergoing CABG surgery were randomized in 3 groups. The first group (N.=25) was administered a placebo injection in the blood cardioplegic solution, the second group (N.=25) received an injection of 4 mmol/L of L-arginine and a third group (N.=25) an injection of 6 mmol/L of L-arginine in the blood cardioplegic solution. Blood samples from the ascending aorta and the coronary sinus catheter were collected before, immediately after and at 20 minutes after aortic cross-clamping. Total plasmatic nitrite and nitrate ratio and lactate release from the myocardium in the collected blood samples were measured.


RESULTS
Seventy-five patients averaging 62+/-7 years of age and undergoing 3.1+/-1 coronary bypass grafts during 41+/-17 minutes of aortic cross clamping time were recruited. Values of total plasmatic nitrite and nitrate ratio remains non-significant before and after aortic clamping and also between groups (P=0.9812 and 0.3573 respectively). Myocardial lactate release was statistically different before and after cross clamping (P=0.0002) and also between the 3 groups (P=0.0311).


CONCLUSIONS
Nondiluted blood cardioplegic solution supplemented with 4 mmol/L of L-arginine was associated with a significant decrease of myocardial lactate release after aortic cross-clamping and reperfusion during CABG surgery.
Carrier
M
M
Department of Cardiac Surgery, Montreal Heart Institute and Université de Montréal, Montreal, QC, Canada. michel.carrier@icm-mhi.org
Perrault
L P
LP
Fortier
A
A
Bouchard
D
D
Pellerin
M
M
D000368:Aged; D001120:Arginine / Q000008:administration & dosage*; D015415:Biomarkers / Q000097:blood; D002314:Cardioplegic Solutions / Q000008:administration & dosage*; D016009:Chi-Square Distribution; D001026:Coronary Artery Bypass / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods*; D006331:Heart Diseases / Q000097:blood / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood; D013997:Time Factors; D016896:Treatment Outcome
D015415:Biomarkers; D002314:Cardioplegic Solutions; D009566:Nitrates; D009573:Nitrites; D019344:Lactic Acid; D001120:Arginine