Back Back
Potassium Binders HF CKD
The Role of Potassium Binders in Heart Failure and Chronic Kidney Disease

Released: November 21, 2023

Ileana L. Piña
Ileana L. Piña, MD, MPH, FAHA, FACC, FHFSA
Activity Information

Activity

Progress
1
Course Completed
Continue
Key Takeaways
  • Individuals with heart failure and chronic kidney disease may experience up to 10 times more hyperkalemia than the general population.
  • When monitoring, diet, and guideline-directed medical therapy are insufficient to maintain normokalemia in heart failure, consider adding a new generation potassium binder: patiromer or sodium zirconium cyclosilicate.

Hyperkalemia occurs in roughly 5% of the general healthy population. In contrast, up to 40% of patients with chronic kidney disease (CKD) experience hyperkalemia, and this number increases with the number of comorbidities reported in each particular patient. When we look at the intersection of diabetes, heart failure (HF), and CKD, the number experiencing hyperkalemia can approach 50%. Due to this, it is imperative that clinicians know how to identify and manage hyperkalemia in patients with HF.

Managing Hyperkalemia With Potassium Binders

Appropriate monitoring, diet, guideline-directed medical therapy (GDMT) optimization, and medication list review can help prevent hyperkalemia in patients with HF and patients with HF and CKD. If a patient remains hyperkalemic after all the above have been optimized, it is important to consider adding a potassium binder. The 2022 American College of Cardiology/American Heart Association/Heart Failure Society of America HF guidelines now have a class IIb recommendation for potassium binders in patients with HF and hyperkalemia. The guidelines define hyperkalemia as a potassium level exceeding 5.5 mEq/L while receiving RAAS inhibition. Initiating a potassium binder to facilitate continuation of RAAS inhibition is preferable to withdrawal of therapy. I do want to point out that potassium binders are approved for hyperkalemia, period. There is no other labeling. As the clinician, you can define how you utilize these agents in the setting of elevated potassium given this very broad indication.

We have 3 available options for potassium binders: sodium polystyrene sulfonate (SPS), patiromer, and sodium zirconium cyclosilicate (SZC). SPS was approved in 1958 before the FDA required cardiovascular data for new medications. In 2009, the FDA issued a black box warning for SPS, with concern for colonic necrosis. Generally speaking, I do not have confidence in its ability to lower potassium, although administering it acutely might make us feel better. In addition, the use of SPS requires a sorbitol solution, adding extra volume to a patient with heart failure. Due to this, I more often utilize one of the new potassium binders for hyperkalemia management.

Patiromer was the first new potassium binder on the market. It works as a nonspecific cation exchange for calcium in the distal colon and does not increase the sodium load. I've been using this drug in my patients with HF and hyperkalemia since it first came out. The prescribing information recommends separating patiromer from other medications by 3 hours to avoid binding any additional agents. Our newest agent, SZC, is a highly selective potassium binder. It removes potassium from the gastrointestinal tract, and you begin to see a reduction in potassium level in about 2 to 3 hours, with roughly 84% of patients achieving a normal potassium within 24 hours. It should also be separated from other medications to avoid any interactions. There have been some reports of edema with SZC, particularly at the higher doses, but I have not seen this when using the lower dose in my practice. Just like patiromer, I seldom have to increase the dose.  So, if you're going to try these agents, try them at the lower dose, titrate as needed, and either should help you achieve your goal of normokalemia. Both are very, very effective, and have demonstrated at least a year of efficacy, so they can be continued without losing their effect.

In addition to their efficacy, both potassium binders are very well tolerated. We have great safety and efficacy data for both new potassium binders, which is why the FDA has given them such a broad indication as mentioned above. It is important to understand what the doses are and potential side effects such as constipation, but overall, the side effects are mild and manageable. I have also found that there is no true rebound with hyperkalemia when these agents are stopped. That was always my fear when I would go to discontinue these medications: that I would suddenly get these large spikes in potassium. In practice, this really doesn't happen. Rather, potassium may rise again over a long period of time. By using these agents, we allow for the enablement of GDMT by protecting our patients from hyperkalemia and improving their outcomes.

Your Thoughts?
Join the discussion below by answering the polling question or go online to view the recorded webinar from HFSA 2023.

Continue

Poll

1.

How often do you initiate potassium binders for the management of hyperkalemia in HF?

Submit