How to manage heart failure with preserved ejection fraction (HFpEF) in an elderly male patient with a history of coronary artery disease (CAD) and recent percutaneous coronary intervention (PCI), presenting with severe dyspnea, bilateral pleural effusion, significantly elevated brain natriuretic peptide (BNP) levels, impaired renal function, and hyponatremia?

Management of Acute Decompensated HFpEF with Hyponatremia

This elderly patient with NYHA Class IV HFpEF requires immediate aggressive decongestion with loop diuretics while carefully monitoring and managing hyponatremia, with urgent referral to a heart failure specialist given the severity of presentation and multiple complicating factors. 1

Immediate Priorities

Confirm the Diagnosis

• This patient meets criteria for HFpEF: LVEF 60%, severely elevated BNP >10,000 pg/mL (far exceeding the hospitalized threshold of >100 pg/mL), bilateral pleural effusions, and NYHA Class IV symptoms 1
• The markedly elevated BNP confirms severe cardiac congestion despite preserved ejection fraction, and this level carries significant prognostic implications for both mortality and rehospitalization 2, 3
• Acute decompensated HFpEF presents with comparable hemodynamic congestion to HFrEF, requiring similar aggressive decongestion strategies 4

Aggressive Decongestion Strategy

Initiate high-dose intravenous loop diuretics immediately to address the severe volume overload manifested by bilateral pleural effusions and Class IV symptoms 1

• Start with IV furosemide bolus (40-80 mg IV, or 2.5 times the home oral dose if already on diuretics), followed by continuous infusion if needed for refractory congestion 1
• Monitor urine output closely (target >3-5 liters negative fluid balance over first 48-72 hours for severe congestion) 1
• Daily weights are mandatory to guide diuretic dosing 1

Managing Hyponatremia During Decongestion

The hyponatremia complicates but does not contraindicate aggressive diuresis - this requires a careful balancing act:

• Continue diuresis despite hyponatremia if the patient has severe volume overload, as fluid restriction and decongestion will ultimately help correct dilutional hyponatremia 1
• Implement strict fluid restriction (typically 1.5 liters/day or less) to address dilutional hyponatremia while diuresing 1
• Avoid hypertonic saline in the setting of volume overload - this will worsen congestion 1
• Monitor sodium levels every 12-24 hours initially; if sodium drops below 125 mEq/L or patient develops neurological symptoms, temporarily reduce diuretic intensity 1

Critical caveat: If hyponatremia is severe (<120 mEq/L) or symptomatic, you must balance the rate of correction (not exceeding 8-10 mEq/L in 24 hours) against the need for decongestion 1

Renal Function Monitoring

The borderline renal dysfunction requires intensive monitoring but should not prevent adequate decongestion:

• Check creatinine and electrolytes (including potassium and magnesium) daily during aggressive diuresis 1, 5
• Accept a 20-30% rise in creatinine during decongestion if urine output remains adequate - this often represents hemoconcentration rather than true worsening kidney injury 1
• If creatinine rises >50% or urine output drops significantly, reassess volume status and consider reducing diuretic dose 1

Guideline-Directed Medical Therapy Optimization

SGLT2 Inhibitors

Initiate an SGLT2 inhibitor once euvolemia is achieved - this is the strongest evidence-based therapy for HFpEF mortality and morbidity benefit 1

• Start empagliflozin 10 mg daily or dapagliflozin 10 mg daily 1
• Can be started even with eGFR as low as 20 mL/min for heart failure indication 1
• Provides additional natriuretic effect which may help with both congestion and hyponatremia 1

Mineralocorticoid Receptor Antagonist

Consider spironolactone 25 mg daily once stable, given the proven mortality benefit in severe heart failure 5

• The RALES trial demonstrated 30% mortality reduction in NYHA Class III-IV heart failure 5
• Critical monitoring required: Check potassium and creatinine within 1 week of initiation, then every 4 weeks for 3 months, given baseline renal dysfunction 5
• Contraindicated if: Baseline potassium >5.0 mEq/L or creatinine >2.5 mg/dL 5
• Reduce dose to 25 mg every other day if potassium rises to 5.0-5.5 mEq/L; discontinue if >5.5 mEq/L 5

Blood Pressure and Heart Rate Control

Optimize blood pressure control targeting <130/80 mmHg, as hypertension worsens diastolic dysfunction 1

• ACE inhibitors or ARBs are reasonable for blood pressure control and comorbid CAD management 1
• Beta-blockers should be continued post-PCI for coronary disease, and may help control heart rate to optimize diastolic filling time 1

Addressing Underlying CAD

Ensure complete revascularization post-PCI, as myocardial ischemia impairs ventricular relaxation and can precipitate HFpEF decompensation 1

• Verify no residual significant coronary disease requiring intervention 1
• Optimize antiplatelet therapy and statin therapy for secondary prevention 1

Pleural Effusion Management

Therapeutic thoracentesis may be necessary if respiratory distress persists despite diuresis:

• Consider if oxygen requirements are high or work of breathing is excessive 1
• Remove 1-1.5 liters maximum per session to avoid re-expansion pulmonary edema 1
• Most pleural effusions will resolve with adequate systemic decongestion 1

Specialist Referral - URGENT

This patient requires immediate heart failure specialist consultation given: 1

• NYHA Class IV symptoms (highest severity)
• Extremely elevated BNP >10,000 pg/mL indicating very high mortality risk 2, 3
• Multiple complicating factors (renal dysfunction, hyponatremia, recent PCI)
• Need for advanced diagnostic evaluation and potential clinical trial enrollment 1

Multidisciplinary collaboration needed with nephrology for hyponatremia and renal dysfunction management, and cardiology for ongoing CAD management 1

Prognostic Counseling

This patient faces high mortality risk: BNP >10,000 pg/mL in HFpEF carries similar poor prognosis as in HFrEF, with elevated risk of both death and rehospitalization 3

• The combination of Class IV symptoms, markedly elevated BNP, renal dysfunction, and hyponatremia indicates advanced disease 2, 6, 3
• Aggressive management may improve outcomes, but realistic prognostic discussions are warranted 1, 3

Common Pitfalls to Avoid

• Do not undertreated congestion due to fear of worsening hyponatremia - inadequate decongestion leads to worse outcomes 1, 4
• Do not stop diuretics for modest creatinine elevation if patient remains volume overloaded 1
• Do not delay SGLT2 inhibitor initiation due to renal dysfunction - these drugs are beneficial even with low eGFR in HF 1
• Do not assume lower BNP in HFpEF means less severe disease - for a given BNP level, HFpEF prognosis equals HFrEF 3