Hi Stephanie. The American Heart Association (AHA), American Red Cross (ARC), and other organizations offer the CPR (and other related certifications). Whether one is accepted over the other is really dependent upon who (what employer or organization) is requiring the certification of you. You should check with the employer/organization to see if the AHA certification is accepted by them. Generally speaking the AHA and ARC certifications are accepted by most organizations, but again it really is up to the employer/organization.
I hope that this helps.