Below what ejection fraction would you avoid referral for AV access creation in a patient with advanced CKD and heart failure with reduced ejection fraction?

I would not refer a patient with advanced CKD and heart failure with an ejection fraction less than 30-35% for a hemodialysis vascular access for fear of worsening the heart failure. In addition, in my experience, if an arteriovenous fistula is placed in such a patient, it usually does not mature du...