Abstract

 The effects of coronary angiography with iohexol upon vein blood rheology were studied before, immediately after and one month after angiography. Haematocrit decreased from 40.5 % to 39.0 % immediately after angiography (p < 0.01). When this was compensated for by in vitro standardisation of sample haematocrits to 45% there was a blood viscosity increase by 10.9 - 15.0 %, at the four studied shear rates 0.8 s^-1, 2.3 s^-1,   19.6 s^-1, and 40.0 s^-1 (p < 0.05 - p < 0.01). In unadjusted samples, i.e. at the patients natural haematocrits, there was only a slight and statistically      non-significant blood viscosity increase. Plasma viscosity decreased immediately after angiography, and was even lower 1 month after angiography. The haematocrit reduction correlated significantly with the iohexol doses (correlation coefficient -0.852, p < 0.001), whereas no significant correlation was found between the contrast volumes and the alterations of blood and plasma viscosity. Except for plasma viscosity, there were no significant differences when the values before angiography and one month later were compared.

Key words: Blood viscosity; Contrast media; Iohexol; Coronary angiography;  Haematocrit; Haemorheology