 Improvement of one or two NYHA functional classes is likely.Coenzyme Q10 adjunctive treatment of heart failure patients is a long-term therapy because patients whose Coenzyme Q10 treatment is discontinued will suffer a clinical relapse.Clinical relapse after discontinuation of long-term Coenzyme Q10 therapy did not follow the same course as clinical relapse after discontinuation of short-term Coenzyme Q10 therapy.