EXERCISE-INDUCED OXIDATIVE STRESS IN PATIENTS DURING THALLIUM STRESS-TESTING

Background: Free radical injury is implicated in the pathogenesis of c oronary artery disease, including atherogenesis and reperfusion/injury . Strenuous physical exercise can cause oxidative stress by several me chanisms, including reperfusion/injury, We hypothesize that exercise-i nduced lipid peroxidation is greater among those with than these witho ut exercise-induced myocardial ischemia.Methods: The effect of physica l exercise stress testing on plasma malonaldehyde (MDA) levels was com pared between patients with (Group A, N = 8) and without (Group B) exe rcise-induced myocardial ischemia by thallium imaging. Analysis: Two-w ay ANOVA was used to compare plasma MDA levels pre- and post-exercise, and paired t-test comparisons were conducted for percent MDA changes between Group A and Group B patients. Results: Two-way ANOVA revealed a significant (P = 0.002) directional difference in response to exerci se between the groups' mean plasma MDA levels (Group A increased by 46 +/- 12.7 percent, Group B decreased by 16.8 +/- 4.6 percent).Conclusi ons: Differences in exercise-induced lipid peroxidation between patien ts with and without thallium documentation of myocardial ischemia have important implications in the development of clinical markers of coro nary artery disease and further research related to atherogenesis.