In the process of extensively searching for a drug elevating the survival ratio in ischemic heart failure, in particular postinfarction heart failure, it is found out that βARKct which is a βARK1 inhibitor is efficacious not only in improving heart function but also elevating survival ratio in postinfarction heart failure. Accordingly, it is expected that the βARK1 inhibitor is efficaciously usable as a remedy for ischemic heart failure which exerts not only an effect of improving heart function but also another effect of elevating survival ratio and, in its turn, contributes to the improved prognosis in patients with ischemic heart diseases.