After being invited to an interview via telephone, do you still have to respond to the confirmation email?

Hi guys,

I received a phone call confirming I'd been interviewed. I just received a confirmation email.

Should I respond to this again? Or would that sound stupid?

I just imagine that an employer gets a lot of emails…and that might be annoying? Or is it unfriendly to not write anything and then just show up the next week? I mean, everything was sorted out over the phone. I even agreed to the job myself.

Thanks for your answers