I can only answer based on when I recently took my 94 year old mother for an angiogram (also through the groin). As a result of what they found they also carried out a minor angioplasty straight away (with my mother's consent of course). She said it was all totally painless - no she wasn't knocked out, just local anaesthesia - normally discharged same day, but kept her in overnight as op was late in the day and she was very tired by that time.
Hope this helps. Good luck to your friend.