I started my car in the morning and turn on the heater to unfog the windows and my car died. Turn the key and nothing fuel pump didnt come on or nothing.

Next day, same thing so i just left it sit for 3 days and it started. Out of curiosity i turned the heater on sure enough killed it again. but the car started back up right after. I turn the heater on once more it stay runnign but dropped the rpms to dam near death.

My question is this electrical(current draw) or something different . Please post with some ideas.