How should I manage a patient with rising NT‑proBNP (279 pg/mL up from 77 pg/mL), worsening leg edema while on Entresto (sacubitril/valsartan) 49/51 mg and torsemide 20 mg, and a serum potassium of 3.2 mmol/L despite 20 mEq potassium supplementation daily?

Management of Rising NT-proBNP and Worsening Edema on Current Heart Failure Therapy

You need to aggressively uptitrate your loop diuretic and address the hypokalemia before it worsens further—increase torsemide to at least 40 mg daily (potentially 80 mg given the rising BNP and persistent edema), add a potassium-sparing diuretic like spironolactone 25 mg daily to simultaneously combat both the hypokalemia and provide additional diuresis through sequential nephron blockade, and increase potassium supplementation to 40 mEq daily while monitoring closely.

Immediate Diuretic Management

Your patient is demonstrating clear diuretic resistance with worsening congestion despite torsemide 20 mg. The rising NT-proBNP from 77 to 279 pg/mL signals inadequate decongestion and increased cardiac wall stress 1.

Loop Diuretic Optimization:

• Double the torsemide dose to 40 mg daily as the first step 2. The FDA labeling for torsemide in heart failure edema recommends starting at 10-20 mg and titrating upward by approximately doubling until adequate diuresis is achieved, with doses up to 200 mg studied 2.
• If 40 mg proves insufficient after 48-72 hours, escalate to 80 mg daily 1.
• Consider twice-daily dosing if once-daily dosing at higher doses remains inadequate 3.
• Torsemide has superior bioavailability compared to furosemide and is already the appropriate choice for this patient 3, 4.

Sequential Nephron Blockade Strategy

Given persistent edema despite loop diuretic therapy, you should implement sequential nephron blockade 1:

Add Spironolactone 25 mg daily - This addresses three critical issues simultaneously:

1. Provides additional diuresis through distal tubule sodium blockade 3
2. Corrects hypokalemia (K+ 3.2 is concerning, especially on a loop diuretic) 3, 5
3. Reduces potassium wasting from the loop diuretic 5

The KDIGO guidelines specifically recommend spironolactone for resistant edema and note it counters hypokalemia from loop diuretics 3. While Entresto (sacubitril/valsartan) increases hyperkalemia risk when combined with mineralocorticoid receptor antagonists 6, your patient's current hypokalemia (3.2 mmol/L) provides a safety margin.

Alternative if spironolactone is contraindicated: Add a thiazide-type diuretic (metolazone 2.5-5 mg once or twice weekly) for sequential nephron blockade 1, 5. However, this will worsen hypokalemia and require aggressive potassium replacement.

Potassium Management

Increase potassium supplementation to 40 mEq daily immediately 5. A potassium of 3.2 mmol/L on 20 mEq daily supplementation indicates:

• Ongoing significant renal potassium wasting from torsemide
• Inadequate replacement dosing
• Risk for arrhythmias, especially if the patient is on other QT-prolonging medications

The addition of spironolactone will help retain potassium, but you need aggressive repletion now. Monitor potassium levels within 3-5 days after these changes 3, 5.

Entresto Considerations

Continue Entresto 49/51 mg - Do not discontinue or reduce this critical guideline-directed medical therapy 6. The rising NT-proBNP suggests inadequate decongestion, not ARNI failure. Research demonstrates:

• NT-proBNP reductions with sacubitril/valsartan occur progressively over months 7, 8, 9
• Patients achieving NT-proBNP reduction to ≤1,000 pg/mL or >30% reduction have better outcomes 7
• Your patient's NT-proBNP of 279 pg/mL, while elevated from 77, remains relatively low and should respond to improved decongestion

Consider uptitration to Entresto 97/103 mg twice daily once volume status is optimized and potassium is stable (ideally 4.0-5.0 mmol/L) 6. Higher doses are associated with greater NT-proBNP reduction and better outcomes 7.

Sodium Restriction

Enforce strict sodium restriction to <2 g/day (<90 mmol/day) 3. Dietary sodium excess is a common cause of diuretic resistance and worsening edema. This is a Class I recommendation from KDIGO guidelines for edema management 3.

Monitoring Plan

Within 3-5 days:

• Serum potassium, sodium, creatinine, BUN
• Clinical assessment of edema and volume status
• Weight (target 0.5-1 kg loss per day depending on edema presence) 10

At 2-4 weeks:

• Repeat NT-proBNP to assess response 4, 11, 7
• Reassess diuretic dosing based on clinical response
• Adjust potassium supplementation based on levels

At 4-6 weeks:

• Consider Entresto uptitration if volume status optimized and potassium stable

Critical Pitfalls to Avoid

1. Do not stop or reduce Entresto - The rising BNP reflects inadequate decongestion, not medication failure 1
2. Do not under-dose the loop diuretic - Torsemide 20 mg is clearly insufficient; doses up to 200 mg are studied and safe 2
3. Do not ignore the hypokalemia - K+ 3.2 requires aggressive correction, especially before adding more diuretic 5
4. Do not add thiazide without addressing potassium first - This will precipitate severe hypokalemia 3, 5
5. Do not attribute worsening renal function (if it occurs) to medication toxicity - Transient creatinine elevation during effective decongestion does not predict long-term kidney dysfunction and should not prompt diuretic reduction if the patient is still congested 1