Use of potassium-binder patiromer for up-titration of renin-angiotensin-aldosterone system inhibition therapy in a patient with chronic heart failure and reduced ejection fraction followed in a multidisciplinary integrated chronic care management programme: a case report.

BACKGROUND: Chronic heart failure (CHF) is a growing epidemic. The cornerstone of pharmacological therapy in CHF patients with reduced ejection fraction (HFrEF) is the inhibition of the renin-angiotensin-aldosterone system (RAAS). One of the adverse effects of RAAS blockade is the development of hyperkalaemia, which often limits the optimization of recommended, Class I treatments. In this context, potassium binders patiromer or sodium zirconium cyclosilicate (ZS-9) provide an opportunity to optimize the pharmacological management of these patients.

CASE SUMMARY: We present a case report illustrating our real-life experience using the potassium-binder patiromer in a patient with HFrEF, in whom recurrent hyperkalaemia (up to 6.3 mmol/L with low doses of enalapril) was preventing titration of RAAS inhibition therapies. Use of patiromer allowed re-introducing ramipril (subsequently switched to sacubitril/valsartan) and eplerenone. Serum potassium levels remained normal with patiromer 16.8 g/24 h, and the patient's tolerance to patiromer was excellent.

DISCUSSION: In patients with HFrEF and recurrent hyperkalaemia, optimal RAAS inhibition is often discontinued. In this context, novel potassium binders such as patiromer or ZS-9 have been shown to be effective in lowering potassium and maintaining normokalaemia, with a good safety profile and patient tolerance, all of which make them promising alternative options. Our preliminary experience suggests that patiromer may be a helpful and well-tolerated treatment option, which may aid in achieving optimal RAAS inhibition in HFrEF patients with recurrent hyperkalaemia. Registries of HFrEF patients will help better understand whether therapies such as patiromer have prognostic benefits through facilitating optimal RAAS blockade.