  Multi-dimensional simulations of advanced nuclear burning stages of massive
stars suggest that the Si/O layers of presupernova stars harbor large
deviations from the spherical symmetry typically assumed for presupernova
stellar structure. We carry out three-dimensional core-collapse supernova
simulations with and without aspherical velocity perturbations to assess their
potential impact on the supernova hydrodynamics in the stalled shock phase. Our
results show that realistic perturbations can qualitatively alter the
postbounce evolution, triggering an explosion in a model that fails to explode
without them. This finding underlines the need for a multi-dimensional
treatment of the presupernova stage of stellar evolution.
