  The proposed Laser Interferometer Space Antenna is expected to detect
gravitational waves from neutron stars and stellar-mass black holes spiraling
into supermassive black holes in distant galactic nuclei. Analysis of the
inspiral events will require careful comparison of the observed signals with
theoretical waveform templates. The comparison could be seriously compromised
if non-gravitational torques modify the orbit of the star. This paper estimates
the torque exerted on an orbiting star as a result of hydrodynamic interactions
with an accretion flow around the supermassive black hole. It is argued that
the majority of inspiral events will take place in low luminosity galactic
nuclei in which the mass accretion rate is low and the accretion occurs via an
advection-dominated flow. The hydrodynamic torque is negligibly small in such
systems and will have no effect on gravitational wave experiments.
