How to manage hyperkalemia in a patient with chronic Congestive Heart Failure (CHF) and a left ventricular Ejection Fraction (EF) of 25%?

Management of Hyperkalemia in Chronic Heart Failure with EF 25%

The priority is to maintain guideline-directed medical therapy (GDMT) for heart failure while managing hyperkalemia, as discontinuing RAAS inhibitors significantly worsens outcomes in patients with severe systolic dysfunction. 1

Severity-Based Management Algorithm

Potassium >6.0 mEq/L (Severe Hyperkalemia)

• Stop RAAS inhibitors temporarily and initiate acute treatment with IV calcium gluconate for cardiac membrane stabilization, followed by insulin/glucose and nebulized beta-2 agonists for intracellular potassium shift 1, 2
• Plan to restart RAAS inhibitors as soon as potassium normalizes, ideally within days to weeks 1

Potassium 5.5-6.0 mEq/L (Moderate Hyperkalemia)

• Reduce the dose of RAAS inhibitors (do not stop completely) 1
• Consider switching from ACE inhibitor to sacubitril/valsartan, which has 37% lower risk of severe hyperkalemia compared to enalapril in patients on mineralocorticoid receptor antagonists 1
• Initiate a potassium binder (patiromer or sodium zirconium cyclosilicate) to enable continuation of GDMT 1

Potassium 5.0-5.5 mEq/L (Mild Hyperkalemia)

• Do not reduce or stop RAAS inhibitors 1
• Add an SGLT2 inhibitor, which reduces hyperkalemia risk by 16% (HR 0.84) while providing mortality benefit in heart failure 1
• Consider initiating a potassium binder to enable uptitration of RAAS inhibitors to target doses 1

Specific Interventions to Maintain GDMT

First-Line Strategy: Add SGLT2 Inhibitor

• SGLT2 inhibitors reduce serious hyperkalemia risk and allow simultaneous optimization of other GDMT components 1
• This approach addresses both heart failure progression and hyperkalemia prevention 1

Second-Line Strategy: Switch to Sacubitril/Valsartan

• In patients on mineralocorticoid receptor antagonists, sacubitril/valsartan reduces severe hyperkalemia by 27% compared to ACE inhibitors 1
• This allows continuation of spironolactone, which is critical for mortality reduction in NYHA class III-IV heart failure 1

Third-Line Strategy: Potassium Binders

• Patiromer or sodium zirconium cyclosilicate enable continuation of high-dose RAAS inhibitors 1
• The DIAMOND trial showed patiromer reduced hyperkalemia >5.5 mEq/L by 37% (HR 0.63) while maintaining RAAS inhibitor therapy 1
• Sodium zirconium cyclosilicate: Start 10g three times daily for 48 hours, then 10g once daily for maintenance 3
• Patiromer: Dosing based on potassium level (typically 8.4-16.8g daily in divided doses) 1

Medication Review and Adjustments

Eliminate Contributing Factors

• Discontinue NSAIDs, potassium supplements, and "low-salt" substitutes with high potassium content 1, 2
• Review and stop other potassium-sparing diuretics (amiloride, triamterene) 1
• Consider stopping or reducing other medications that increase potassium: trimethoprim, heparin, calcineurin inhibitors 2

Diuretic Optimization

• Increase loop diuretic dose (not potassium-sparing diuretics) to enhance potassium excretion 1, 2
• Ensure euvolemia, as volume overload worsens outcomes more than transient kidney function changes during decongestion 1

Monitoring Protocol

Initial Phase (First 12 Weeks)

• Check potassium and creatinine at 1,4,8, and 12 weeks after starting or adjusting spironolactone 1
• Monitor at 2-4 weeks after initiating or uptitrating any RAAS inhibitor 2

Maintenance Phase

• Check potassium at 6,9, and 12 months, then every 6 months 1
• More frequent monitoring (every 1-3 months) if creatinine clearance <40 mL/min 2, 4

Critical Pitfalls to Avoid

Do Not Permanently Discontinue RAAS Inhibitors

• GDMT withdrawal is associated with worse outcomes than managing hyperkalemia with adjunctive therapies 1
• Over 80% of patients can be rechallenged successfully with close monitoring, even without potassium binders 1

Do Not Use Sodium Polystyrene Sulfonate (Kayexalate) Chronically

• Avoid chronic use due to risk of bowel necrosis and lack of efficacy data 1
• If used acutely, avoid formulations with sorbitol 1

Monitor for Edema with Potassium Binders

• Sodium zirconium cyclosilicate contains 400mg sodium per 5g dose; monitor for fluid overload and adjust loop diuretics accordingly 3
• Edema occurred in 16% of patients on 15g daily doses 3

Special Considerations for This Patient

With an EF of 25%, this patient has severe systolic dysfunction and requires maximal GDMT including ACE inhibitor/ARB/ARNI, beta-blocker, mineralocorticoid receptor antagonist, and SGLT2 inhibitor for mortality benefit 1. The goal is to achieve target doses of all four pillars while managing hyperkalemia aggressively with adjunctive therapies rather than GDMT dose reduction 1.