Ff. Immer et al., Influence of the ultrasound contrast agent Levovist((R)) on human nailfoldcapillary microcirculation, ANGIOLOGY, 51(2), 2000, pp. 123-129
Little is known about the behavior of ultrasound contrast microbubbles in h
uman capillaries. The evaluation of circulatory effects of echo contrast me
dia may bring valuable information for the interpretation of echo contrast
phenomena in the human myocardium. In 12 healthy volunteers (aged 31 +/- 6.
7 years; five women), nailfold capillaries were examined by means of TV mic
roscopy, The authors investigated acral microcirculation at rest and after
local cold application with and without saccharide-based microbubbles (10 m
L Levovist(R) 300 mg/mL IV), The mean blood flow velocity at rest was 1.18
+/- 0.18 mm/s (mean value +/- 1 SD) and 1.11 +/- 0.11 mm/s (mean value +/-
1 SD) after the injection of Levovist(R) (ns). One minute after local cold
exposure a decrease of the blood flow velocity by 61% before and by 75% aft
er intravenous Levovist(R) was found. In both groups the cold-induced decre
ase of blood flow velocity was statistically significant (p<0.01), whereas
there was no significant difference in flow reaction between the two groups
. No wall adhesion of blood cells or extravasation of contrast into the sur
rounding tissue was detected. After intravenous injection of a regular dose
of saccharide-based microbubbles Levovist(R), no change of blood cell flow
velocity and no wall adhesion or extravasation could be found at rest and
after cold application in human nailfold capillaries. Since microcirculator
y flow characteristics in the finger nailfold capillaries are not influence
d by Levovist(R), it might be assumed also that myocardial blood flow behav
ior remains unchanged, so that this contrast agent may be used as a flow tr
acer for cardiac investigation.