Heart failure (HF), the representative end-stage of most heart diseases, has a heterogeneous course that makes it difficult to know with certainty whether a patient is in the advanced stage of the disease [1]. In advanced HF, therapies such as cardiac resynchronization (CRT) or an implantable cardioverter defibrillator (ICD) may not be suitable or accepted due to disability, comorbidity, or the patient's preferences [2]. Despite improvements in treatment, advanced HF continues to have substantial morbidity and mortality.
