Kagase A, et al. - Researchers evaluated the prognostic value of hyponatremia in patients who underwent transcatheter aortic valve replacement (TAVR) using data from the Optimized CathEter vAlvular iNtervention (OCEAN)-TAVR Japanese multicenter registry. Non-uniform patient features were adjusted via propensity-matching analysis. Patients were divided into 2 groups: those with and those without hyponatremia. The hyponatremia group vs the non-hyponatremia group had higher all-cause and cardiovascular mid-term mortality during follow-up. No difference was found in non-cardiovascular mortality between the two groups in both the overall and matched model. Overall, for the prediction of early and mid-term clinical outcomes after TAVR, pre-procedural hyponatremia may serve as a useful marker.