Lee H, et al. - This nested case–control study of the Korean Acute Heart Failure registry explored the link between right ventricular (RV) dysfunction and hyponatraemia, as well as the prognostic impact of this link in patients with acute heart failure (AHF). Findings demonstrated that in this patient population, hyponatraemia was more common with RV dysfunction. A more significant association of RV dysfunction, rather than hyponatraemia, with patients’ prognosis, was evident. This finding recommended the utility of RV dysfunction instead of hyponatraemia per se be considered in heart failure (HF) risk models.