Elemental content of erythrocytes from patients undergoing Coronary Artery Bypass Grafting (CABG) surgery using PIXE analysis

Antioxidant activity in off and on-pump coronary artery bypass grafting and valve replacement surgery

OBJECTIVES

Cardiac surgeries initiate oxidative stress, increasing organ dysfunction development and mortality. The present study investigated the superoxide dismutase (SOD) activity, as an antioxidant enzyme, in patients undergoing coronary artery bypass (CABG) and heart valve replacement surgeries.

METHODS

A prospective study was performed on patients with proven coronary artery disease (CAD) or valvular heart disease (VHD) candidates for on- or off-pump CABG and valve replacement surgery. Serum SOD activity was measured preoperatively, at 24 h postoperatively, and at the time of discharge. In addition, echocardiography was performed before surgery and at discharge.

RESULTS

A total of 48, 51, and 47 patients were enrolled in the on-pump, off-pump CABG, and valve replacement groups, respectively. Baseline serum SOD activity showed no significant association with BMI, age, and blood pressure in either CAD or VHD patients. The SOD values decreased at the 24 h postoperative time and then increased at the time of discharge in all groups, except for a slight decrease in the on-pump group. The changes in serum SOD values were not significantly different for the three surgical groups.

CONCLUSIONS

The serum SOD activities fell significantly after CABG and valve replacement surgery. Further investigation is emphasized for the role of SOD in oxidative stress after cardiac surgery.

Changes in serum zinc and copper concentrations in patients with cardiovascular disease following cardiac surgery

The trace elements copper (Cu) and zinc (Zn) are essential for maintaining oxidative balance, and cardiac surgery is known to provoke an increase in oxidative stress. We investigated the variations in serum Zn and Cu concentrations before and after surgery in patients undergoing on- and off-pump CABG and heart valve replacement. We performed a prospective study on patients undergoing on- or off-pump CABG, or heart valve replacement surgery (48, 51, and 47 patients, respectively). Venous blood samples were obtained, and serum Cu and Zn concentrations were measured preoperatively, 24 h postoperatively, and the time of discharge. In addition, echocardiography was carried out on all patients before surgery and again on the day of discharge. We found the temporal changes in Cu, Zn, and Zn/Cu ratio were significantly different in all three groups of surgery (p < 0.05). In each group, Cu and Zn values and Zn/Cu ratio decreased at the 24-h postoperative time and rose at the discharge time. There were no significant differences between surgery groups in the changes induced in Zn or Cu values (p > 0.05). In conclusion, the concentrations of Cu and Zn were markedly reduced after on- and off-pump CABG and valve replacement surgery. This may suggest that supplementary Zn and Cu administration could be beneficial during open-heart surgeries. However, more long-term studies with more patients are needed to confirm this hypothesis.