Hemorheological and oxygen free radical associated alterations during and after percutaneous transluminal coronary angioplasty

Abstract

Percutaneous transluminal coronary angioplasty (PTCA) is a frequently used method in the treatment of coronary artery disease. Coronary stenosis, endothelial injury, and ischemia-reperfusion caused by the balloon inflation and deflation during this procedure can cause several changes in blood flow. In our study 19 patients (mean age: 58 +/- 9 years) undergoing PTCA were examined. For the laboratory measurements several blood samples were taken from the femoral vein and the coronary sinus before and 30 minutes after PTCA, and from the cubital vein 1, 2, 5 days and 1, 6 months after PTCA. Among hemorheologic parameters hematocrit, plasma fibrinogen level, plasma and whole blood viscosities were measured and corrected blood viscosity value was calculated. To characterize the oxidative stress, samples were analyzed for thiobarbituric acid reactive substances (TBARS) of blood as a marker of lipidperoxidation and changes in the antioxidant system were investigated by measuring the activity of superoxide dismutase, catalase and the concentration of glutathione; superoxide generating capacity of isolated leukocytes and platelet aggregation were examined as markers of cellular activation. Plasma fibrinogen concentration increased markedly during the first and second day after PTCA (p < 0.001), which was accompanied by the elevation of plasma viscosity (p < 0.05). Plasma fibrinogen returned to the baseline at the one-month check-up visit, but there was a significant increase in its concentration by the end of the sixth month follow-up. Apparent whole blood viscosity at 90 s (-1) showed gradually increasing values up to the one- and six-month check-up visits (p < 0.01), which can partially be explained by the elevation of hematocrit. Corrected blood viscosity was significantly elevated on the fifth day already (p < 0.01), and one month later also. Superoxide production of leukocytes showed an increasing tendency (p = 0.05), and blood TBARS was elevated after one day (p < 0.05) and remained higher during the following days. Catalase activity showed significantly increasing values (p < 0.01) during the hospital phase, then at the end of the first month. SOD activity and spontaneous platelet aggregation were higher in the samples from the coronary sinus than in those from the peripheral vein before the procedure; 30 minutes after PTCA increased levels in the peripheral sample were found (p < 0.01). Our findings indicate that PTCA may cause significant changes in the hemorheologic and free radical associated parameters, which can affect the final outcome of this intervention.