From multi-epoch adaptive optics imaging and integral field unit spectroscopy we report the discovery of an expanding and narrowly confined bipolar shell surrounding the helium nova V445 Puppis ( Nova Puppis 2000 ) .
An equatorial dust disc obscures the nova remnant , and the outflow is characterised by a large polar outflow velocity of 6720 \pm 650 km s ^ { -1 } and knots moving at even larger velocities of 8450 \pm 570 km s ^ { -1 } .
We derive an expansion parallax distance of 8.2 \pm 0.5 kpc and deduce a pre-outburst luminosity of the underlying binary of \log L / L _ { \odot } = 4.34 \pm 0.36 .
The derived luminosity suggests that V445 Puppis probably contains a massive white dwarf accreting at high rate from a helium star companion making it part of a population of binary stars that potentially lead to supernova Ia explosions due to accumulation of helium-rich material on the surface of a massive white dwarf .