If you go to the ER for chest pain can you refuse bloodwork and get only an EKG?

Imagine that someone has a serious case of trypanophobia. And by ‘serious’, I mean that it’s not a case of “needles freak me out so I’d rather not get a vaccination”. I mean real, diagnose-able trypanophobia.

Imagine that this person starts experiencing chest pain and goes to the ER.

I know that standard practice is blood work and an EKG. Imagine that this person wants to refuse blood work, but would like an EKG.

SO, THE QUESTION(s):

Is someone who is experiencing chest pains allowed to refuse specific types of treatment?

Is it against the law for the emergency room to deny alternative medical treatment/testing to someone, when an alternative exists and is feasible?