 Coenzyme Q10 is not a fast-acting substance in heart failure.If the patient's condition is so severe that he or she does not have 40 – 60 to respond, then the CoQ10 treatment is likely to be ineffective.Once the patient responds to the Coenzyme Q10 treatment, however, and his or her heart function begins to improve, then the clinical course becomes more stable and the patient's condition is easier to manage.