Role of leucocytes in free radical production during myocardial revascularisation.
OBJECTIVE
To evaluate the role of leucocytes in free radical production in patients with depressed or normal ejection fraction undergoing coronary bypass.


METHODS
Two randomised control trials.


METHODS
Tertiary care centre.


METHODS
In the first study, 22 patients with ejection fractions of < or = 40% received blood cardioplegic reperfusion with (n = 11) or without (n = 11) leucocyte depletion. In the second study, 22 patients with ejection fractions > or = 45% received either leucocyte depleted (n = 11) or blood cardioplegia (n = 11).


METHODS
Glutathione, hypoxanthine, and lipid peroxidation products were measured in coronary sinus blood and plasma before aortic cross clamping and at 0, 15, and 30 minutes after unclamping. Haemodynamic variables and creatine kinase MB isoenzymes were monitored on the first postoperative day. Comparison between treatments was performed on difference (delta) between measurements at time 0 and at baseline, and on slopes obtained by fitting measurements after unclamping with a linear regression model.


RESULTS
At unclamping no difference in delta for plasma glutathione redox ratio (oxidised/total glutathione, %) was observed between treated and control groups with low ejection fraction (delta = 16 (SD 8.39) and 24 (7.0) redox ratio %, respectively). Baseline value recovery rate (redox ratio %/min) was significantly faster in treated v control patients (slope -0.912 (0.380) v -0.158 (0.200), P < 0.005, respectively). Cardiac index showed a trend to greater improvement in the treated group (slope 0.04 (0.03) v 0.003 (0.002) 1/min/m2/h, P < 0.02, treated v controls, respectively). In patients with normal ejection fraction, leucocyte depletion did not result in significant improvement v controls.


CONCLUSIONS
Leucocyte depletion seems to provide benefit only in patients with left ventricular dysfunction.
De Vecchi
E
E
Department of Laboratory Medicine, IRCCS H San Raffaele, Milan, Italy.
Paroni
R
R
Pala
M G
MG
Di Credico
G
G
Agape
V
V
Gobbi
C
C
Bonini
P A
PA
Paolini
G
G
Grossi
A
A
D000368:Aged; D002315:Cardiopulmonary Bypass; D003327:Coronary Disease / Q000097:blood* / Q000601:surgery; D005609:Free Radicals; D005978:Glutathione / Q000097:blood*; D006324:Heart Arrest, Induced; D006801:Humans; D019271:Hypoxanthine / Q000097:blood*; D007962:Leukocytes / Q000502:physiology*; D015227:Lipid Peroxidation; D008875:Middle Aged; D009204:Myocardial Revascularization; D010084:Oxidation-Reduction
D005609:Free Radicals; D019271:Hypoxanthine; D005978:Glutathione