Free radical activity and left ventricular function after thrombolysis for acute infarction

• Published in: British Heart Journal 1993-02, Vol.69 (2), p.114-120
• Main Authors: Davies, S W, Ranjadayalan, K, Wickens, D G, Dormandy, T L, Umachandran, V, Timmis, A D
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Blood. Blood coagulation. Reticuloendothelial system; Female; Free Radicals - metabolism; Humans; Male; Medical sciences; Middle Aged; Myocardial Infarction - blood; Myocardial Infarction - drug therapy; Myocardial Reperfusion Injury - blood; Myocardial Reperfusion Injury - physiopathology; Pharmacology. Drug treatments; Streptokinase - therapeutic use; Sulfhydryl Compounds - blood; Thiobarbituric Acid Reactive Substances - metabolism; Thrombolytic Therapy; Ventricular Function, Left - physiology
• ISSN: 0007-0769; 1355-6037; 1468-201X; 2053-5864
• DOI: 10.1136/hrt.69.2.114

BACKGROUND--Experimental data suggest that reperfusion injury involving free radicals contributes to the impairment of left ventricular function after successful thrombolysis. METHODS--In 72 patients presenting with acute myocardial infarction, markers of free radical activity were measured before streptokinase and two hours later. Thiobarbituric acid reactive material (TBA-RM) reflects lipid peroxidation by free radicals, and the concentration of plasma total thiols (34 patients) reflects oxidative stress. Coronary arteriography was performed at 18-72 hours after thrombolysis to determine coronary patency, and left ventricular function was assessed by ventriculography and from QRS scoring of the electrocardiogram. RESULTS--The infarct related artery was patent (Thrombolysis In Myocardial Infarction Trial grade 2 or better) in 60 (83%) and occluded in 12. In the 60 with a patent artery, the concentration of TBA-RM increased after streptokinase by (mean (SD)) 9.2 (14.0) nmol/g albumin, whereas in the 12 with an occluded artery TBA-RM decreased by 7.0 (11.3) nmol/g albumin (p < 0.01 between groups). In those with a patent artery the rise in TBA-RM associated with thrombolysis correlated with left ventricular ejection fraction (R = -0.41, p < 0.002), and with the QRS score (R = +0.38, p = 0.003). Plasma total thiol concentrations decreased by 12.7 (31.1) mumol/l in those with a patent artery, and this decrease associated with thrombolysis correlated with left ventricular ejection fraction (R = +0.39, p < 0.02) but not with the QRS score (R = -0.2, NS). CONCLUSIONS--These findings suggest that reperfusion injury mediated by free radicals may be of clinical importance in humans.