Free-radical activity after primary coronary angioplasty in acute myocardial infarction.

Free-radical activity in coronary venous outflow was assessed before and after reperfusion in nine patients with acute infarction who had undergone successful recanalization of the infarct-related artery by primary coronary angioplasty. Free-radical activity was measured in serum samples from coronary venous outflow over a timed period of 24 hours by using (1) the percentage molar ratio (PMR) of the diene conjugate 9,11-linoleic acid, and (2) malonaldehyde concentration. Preangioplasty PMR means lay within the normal range, but showed a marked increase soon after successful recanalization. Relative to baseline, the changes over time reached statistical significance between 2 and 60 minutes. No statistically significant changes in malonaldehyde occurred over the study period. We conclude that successful recanalization of the infarct artery is associated with significantly elevated free-radical activity, as measured by the PMR of conjugated diene, in coronary venous outflow. Such patients may be at risk from free radical mediated reperfusion injury.