TRANSIENT RELEASE OF LIPID-PEROXIDATION PRODUCTS AS A NONINVASIVE MARKER OF SUCCESSFUL REPERFUSION AFTER THROMBOLYSIS FOR MYOCARDIAL-INFARCTION

Objectives-To evaluate an increase in plasma concentration of thiobarb ituric acid reactive substances as a non-invasive biochemical test of reperfusion after thrombolysis and to investigate the relation between the inflammatory response after acute myocardial infarction and the p roduction of the substances. Methods-Venous samples were taken from 19 patients receiving thrombolysis for acute myocardial infarction befor e the start of therapy and every hour afterwards up to 5 hours and the n at 24 and 48 hours and the concentration of thiobarbituric acid reac tive substances measured. These substances are markers of lipid peroxi dation induced by free oxygen radicals. Early reperfusion was judged b y regression of ST elevation and late coronary artery patency from the results of coronary angiography 24-72 hours after thrombolysis. Resul ts-The concentration of thiobarbituric acid reactive substances increa sed in only 6 out of 14 patients with signs of early reperfusion. In p atients with late coronary artery patency the corresponding number was 6 out of 15. However, a significant increase in the concentration of thiobarbituric acid reactive substances was found for the whole group 24 and 48 hours after treatment. The change in concentration in serum correlated significantly with that of C reactive protein-an acute phas e reactant (r = 0.62, P < 0.01)-but not to the serum activities of mar kers of infarct size such as creatine kinase B and lactate dehydrogena se. Conclusions-The fluorimetric assay used in this study to measure t he concentration of thiobarbituric acid reactive substances seems to b e an insensitive method of detecting reperfusion after thrombolysis fo r myocardial infarction. The increase in concentrations found 24 and 4 8 hours after treatment correlated with C reactive protein concentrati ons but not with those of markers of infarct size.