We read with interest the article, “Association between serum potassium variability during admission for decompensated heart failure and outcomes,” published in the European Journal of Internal Medicine [1]. The authors address a clinically relevant question: whether in-hospital variability of serum potassium conveys prognostic information beyond single values among patients admitted for decompensated heart failure (HF). The topic is timely for ward and ICU practice, where electrolyte checks are frequent yet their temporal dynamics are rarely incorporated into risk assessment.
