Lipid peroxidation associated with successful thrombolysis

In 50 patients receiving thrombolytic treatment for acute myocardial infarction, peripheral venous blood samples were taken before streptokinase and 2 h later for assay of markers of free radical activity. Coronary arteriography was carried out within 72 h of thrombolysis. In the 42 patients with patent arteries after thrombolysis, the levels of thiobarbituric-acid-reactive material (TBA-RM), which reflects lipid peroxidation by free radicals, rose after streptokinase by 10.5 (SD 9.6) [corrected] nmol/g albumin, whereas in the 8 whose arteries remained occluded TBA-RM fell by 14.7 (8.0) [corrected] nmol/g albumin. There was no significant change in the 18:2 (9,11)/18:2 (9,12) molar ratio, an indicator of lipid isomerisation, either between the groups or after streptokinase. Thus, after successful thrombolysis there is a rise in lipid peroxidation, not seen in patients whose arteries remain occluded. This finding suggests free-radical-mediated damage at the time of reperfusion, and provides indirect evidence of reperfusion injury in man. This study provides evidence associating indicators of free radical activity with documented myocardial reperfusion in man.