IntroductionIn blood circulation, the vessel branching angle may have hemodynamic
consequences. We hypothesized that there is a hemodynamically optimal range for the
renal artery branching angle.MethodsPosttransplant kinetics of eGFR (estimated glomerular
filtration rate) data were analyzed regarding the donor and implant sides (right-to-right,
left-to-right position) (n=46). The renal artery branching angle from the aorta of
a randomly selected population was measured using an X-ray angiogram (n=44). Computational
fluid dynamics simulation was used to elucidate the hemodynamic effects of angulation.Results,
and DiscussionRenal transplant patients receiving a right donor kidney to the right
side showed faster adaptation and higher eGFR values than those receiving a left donor
kidney to the right side (eGFR: 65±7 vs 56±6 ml/min/1.73 m2; P <0.01). The average
left side branching angle was 78°, and the right side was 66°. Simulation results
showed that pressure, volume flow and velocity were relatively constant between 58°
and 88°, indicating that this range is optimal for the kidneys. The turbulent kinetic
energy shows no significant change between 58° and 78°.ConclusionThe results suggest
that there is an optimal range for renal artery branching angle from the aorta where
hemodynamic vulnerability caused by the degree of angulation is the lowest, which
should be considered during kidney transplantations.
