Finerenone in everyday heart failure care

Background Finerenone is a non-steroidal mineralocorticoid receptor antagonist (MRA) increasingly used in patients with heart failure, particularly those with concomitant chronic kidney disease and high cardiorenal risk. While MRAs represent one of the cornerstones of heart failure management, their use in routine clinical practice is frequently limited by concerns regarding hyperkalaemia and deterioration in renal function. Real-world data on the tolerability of finerenone in older, frailer, and more comorbid populations than those enrolled in clinical trials remains limited. Purpose To describe real-world use of finerenone in patients with heart failure and to evaluate changes in serum potassium and renal function following initiation, as well as the incidence and management of hyperkalaemia and other adverse effects. Methods We conducted a retrospective, single-centre cohort study of consecutive patients with heart failure treated with finerenone between October 2023 and December 2025. Laboratory values obtained prior to finerenone initiation and during follow-up were analysed using paired t-tests. Episodes of hyperkalaemia, use of potassium-binding agents, and documented adverse effects were recorded throughout the treatment period. Results Sixty-four patients were included (median age 75.5 years [IQR 69–92], 44% women), with a median finerenone treatment duration of 11 months (IQR 5–27). Serum potassium remained stable following finerenone initiation (4.53 ± 0.42 to 4.63 ± 0.44 mmol/L; p=0.177). Renal function was largely preserved, with no significant changes in serum creatinine (134 ± 46 to 141 ± 61 µmol/L; p=0.221) or estimated glomerular filtration rate (45 ± 20 to 45 ± 21 mL/min/1.73 m²; p=0.869). A modest increase in urea was observed (10.95 ± 5.13 to 12.19 ± 6.22 mmol/L; p=0.029). Hyperkalaemia occurred in six patients during follow-up; all were treated with sodium zirconium cyclosilicate, with no recurrent episodes documented thereafter. Overall, ten patients received sodium zirconium cyclosilicate at some point during finerenone therapy, including four who were already receiving potassium binders prior to initiation. No other adverse effects were recorded. Conclusions In an elderly, heterogeneous real-world cohort of heart failure patients, finerenone use over a median follow-up of 11 months was associated with stable serum potassium levels and preserved renal function. Hyperkalaemia occurred infrequently and was effectively managed with potassium-binding therapy. These findings support the tolerability of finerenone in routine clinical practice and underscore the importance of proactive laboratory monitoring and access to potassium binders to facilitate ongoing therapy in patients at risk.