Hyperkalemia and Renin-Angiotensin-Aldosterone System Inhibitors Dose Therapy in Heart Failure With Reduced Ejection Fraction

An international Delphi consensus regarding best practice recommendations for hyperkalaemia across the cardiorenal spectrum

AIMS

Renin-angiotensin-aldosterone system inhibitors (RAASi) are guideline-recommended therapy for individuals with cardiorenal disease. They are associated with increased risk of hyperkalaemia, a common and life-threatening disorder for this population. RAASi-induced hyperkalaemia often leads to dose reduction or discontinuation, reducing cardiorenal protection. Guideline recommendations differ between specialties for the clinical management of hyperkalaemia. Using a modified Delphi method, we developed consensus recommendations for optimal management of hyperkalaemia in adults with cardiorenal disease.

METHODS AND RESULTS

An international steering group of cardiologists and nephrologists developed 39 statements regarding hyperkalaemia care, including risk factors and risk stratification, prevention, correction, and cross-specialty coordination. Consensus was determined by agreement on an online questionnaire administered to cardiorenal specialists across Europe and North America. The threshold for consensus agreement was established a priori by the steering group at 67%. Across November 2021, 520 responses were received from Canada (n = 50), France (n = 50), Germany (n = 54), Italy (n = 58), Spain (n = 57), the UK (n = 49), and the US (n = 202); 268 from cardiologists and 252 from nephrologists. Twenty-nine statements attained very high agreement (≥90%) and 10 attained high agreement (≥67%-<90%), with strong alignment between cardiologists and nephrologists.

CONCLUSION

A high degree of consensus regarding hyperkalaemia evaluation and management exists among healthcare professionals. Based on high levels of agreement, the steering group derived six key recommendations for hyperkalaemia prevention and management in people with cardiorenal disease. Future studies examining the quality of hyperkalaemia care delivery are required.

Serum potassium and heart failure: association, causation, and clinical implications

Dyskalemia (hypo- and hyperkalemia) is a common clinical encounter in patients with heart failure (HF), linked to underlying pathophysiologic alterations, pharmacological treatments, and concomitant comorbidities. Both hypo- and hyperkalemia have been associated with a poor outcome in HF. However, it is not known if this association is causal. In order to investigate this relation, we implemented the Bradford Hill criteria for causation examining the available literature. Of note, hypokalemia and low-normal potassium levels (serum potassium < 4.0 mmol/L) appear to be associated with adverse clinical outcomes in HF in a cause-and-effect manner. Conversely, a cause-and-effect relationship between hyperkalemia (serum potassium > 5.0 mmol/L) and adverse clinical outcomes in HF appears unlikely. We also examined the benefits of renin-angiotensin-aldosterone system inhibitors (RAASi) therapy uptitration in patients with HF and reduced ejection fraction. In fact, hyperkalemia often limits RAASi use, thereby negating or mitigating their clinical benefits. Finally, serum potassium levels in HF should be maintained within the range of 4.0-5.0 mmol/L, and although the correction of hyperkalemia does not appear to improve clinical outcomes per se, it may enable the optimal titration of RAASi, offering indirect clinical benefit.

Effect of patiromer on serum potassium in hyperkalemic patients with heart failure: Pooled analysis of 3 randomized trials

BACKGROUND

Hyperkalemia (HK) is a serious medical condition that can cause potentially fatal cardiac arrhythmias. Patients with heart failure (HF) are at risk of HK due to underlying chronic kidney disease and use of guideline-recommended renin-angiotensin-aldosterone system inhibitors. Patiromer, a sodium-free, non-absorbed potassium (K⁺) binder, is indicated for the treatment of HK.

OBJECTIVE

To evaluate the consistency of patiromer's effect on lowering serum K⁺ in patients with HF and HK using pooled data from three clinical trials.

METHODS

This post-hoc analysis evaluated the efficacy and safety of patiromer for management of HK over a 4-week treatment period using combined data from three clinical trials (AMETHYST-DN, OPAL-HK and TOURMALINE). Eligible patients had HK (serum K⁺ > 5.0 mEq/L) at study entry. Starting doses of patiromer ranged from 8.4 to 33.6 g/day. In this analysis, efficacy was assessed as the mean (± standard error [SE]) change in serum K⁺ from baseline to Week 4. Safety outcomes evaluated included the incidence and severity of adverse events (AEs) during the 4-week treatment period.

RESULTS

In total, 653 patients who received ≥1 dose of patiromer were evaluable for efficacy (214 diagnosed with HF and 439 without HF). Mean baseline serum K⁺ was 5.4 mEq/L. Patient characteristics were generally similar between the HF and non-HF subgroups. Serum K⁺ decreased to <5.0mEq/L within one week of patients starting patiromer, reaching a nadir after 3 weeks in both the HF and non-HF subgroups (4.59 mEq/L and 4.64 mEq/L, respectively). The mean ± SE change from baseline to Week 4 in serum K⁺ was -0.79 ± 0.06 mEq/L (95% CI: -0.91, -0.68) in patients with HF and - 0.75 ± 0.02 mEq/L (95% CI: -0.79, -0.70) in patients without HF. AEs occurred in 31% of patients with HF and 37% of patients without HF and were mostly mild or moderate in severity. The most common AEs were constipation (HF patients: 7%, non-HF patients: 5%) and diarrhea (HF patients: 2%, non-HF patients: 4%). AEs leading to discontinuation of patiromer occurred in 7% of patients with HF and in 3% of patients without HF.

CONCLUSIONS

In this pooled analysis of patients with HK, patiromer was generally well tolerated and reduced serum K⁺ similarly in patients with and without HF over 4 weeks.