Is your feature request related to a problem? Please describe.
e2e-VarNet (https://arxiv.org/abs/2004.06688), a state-of-the-art MRI reconstruction model is not available in MONAI.

Describe the solution you'd like
Add its implementation.

Describe alternatives you've considered
N/A

Additional context