Isoprostanes and oxidative stress in off-pump and on-pump coronary bypass surgery.
BACKGROUND
Conventional on-pump coronary artery bypass grafting (CABG) is associated with a systemic inflammatory response and by an increased production of reactive oxygen species, whereas off-pump coronary artery bypass grafting (OPCAB) is thought to be accompanied by less oxidative stress. Urinary isoprostane iPF2alpha-III is a new marker reflecting oxidative stress; it has emerged as the most reliable marker of oxidative stress status in vivo. This study was designed to ascertain whether OPCAB compared with CABG represents a surgical strategy that avoids oxidative stress. To this end urinary isoprostanes and other established oxidative stress markers were measured during the first 24 hours after CABG and OPCAB.


METHODS
Fifty low-risk coronary patients were randomly assigned to CABG or OPCAB. Urinary isoprostane iPF2alpha-III levels, plasma levels of free malondialdehyde, and total antioxidant status were measured before, during, and up to 24 hours after surgery.


RESULTS
In OPCAB iPF2alpha-III excretion remained unchanged throughout the study. As expected, in CABG iPF2alpha-III levels significantly increased during surgery and returned at baseline 24 hours later. Free malondialdehyde behaved similarly, with no change in OPCAB and sharp increases during CABG. Conversely, total antioxidant status showed a sharp drop during CABG, followed by a slow recovery, whereas a significantly lower drop occurred in OPCAB.


CONCLUSIONS
In this randomized study in low-risk coronary patients, OPCAB revealed less perioperative oxidative stress, as reflected by lack of excretion of iPF2alpha-III in urine, by lack of increase of plasma free malondialdehyde, and by lower decreases in plasma total antioxidant status.
Cavalca
Viviana
V
Centro Cardiologico Monzino IRCCS, University of Milan, Milan, Italy.
Sisillo
Erminio
E
Veglia
Fabrizio
F
Tremoli
Elena
E
Cighetti
Giuliana
G
Salvi
Luca
L
Sola
Alessandra
A
Mussoni
Luciana
L
Biglioli
Paolo
P
Folco
Giancarlo
G
Sala
Angelo
A
Parolari
Alessandro
A
D000368:Aged; D000975:Antioxidants / Q000032:analysis; D015415:Biomarkers / Q000652:urine; D001026:Coronary Artery Bypass; D047549:Coronary Artery Bypass, Off-Pump; D005260:Female; D006801:Humans; D007249:Inflammation; D028421:Isoprostanes / Q000652:urine*; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D012307:Risk Factors
D000975:Antioxidants; D015415:Biomarkers; D028421:Isoprostanes; D008315:Malondialdehyde