What is the treatment approach for acute on chronic congestive heart failure with reduced ejection fraction (CHFrEF)?

Treatment of Acute on Chronic CHFrEF

The management of acute on chronic heart failure with reduced ejection fraction (CHFrEF) requires immediate stabilization with IV diuretics and vasodilators, followed by optimization of guideline-directed medical therapy (GDMT) including ARNI/ACEi/ARB, beta-blockers, MRAs, and SGLT2 inhibitors. 1, 2

Initial Management of Acute Decompensation

Immediate Interventions

• Oxygen therapy to maintain saturation >90%
• IV loop diuretics (furosemide 20-40mg IV, can be increased based on response) 1
• Vasodilators (IV nitroglycerin) for patients with pulmonary congestion and adequate blood pressure (SBP >100 mmHg) 1
• Monitor vital signs, urine output, and electrolytes every 1-2 days while hospitalized 1

Laboratory Assessment

• Cardiac troponin
• BUN/creatinine
• Electrolytes (sodium, potassium)
• Natriuretic peptides (BNP or NT-proBNP)
• Liver function tests
• TSH (in newly diagnosed HF) 1

Stabilization Phase

Once the patient is hemodynamically stable (typically within 24-48 hours):

1. Assess volume status - aim for euvolemia (patient's "dry weight")

2. Evaluate for precipitating factors:

   • Medication non-adherence
   • Dietary indiscretion (sodium/fluid)
   • Arrhythmias (especially atrial fibrillation)
   • Infection
   • Acute coronary syndrome
   • Uncontrolled hypertension

3. Echocardiography within 48 hours if cardiac function is unknown or if mechanical complications are suspected 1

Optimization of Medical Therapy

Core Medications to Initiate/Optimize

1. ARNI/ACEi/ARB:

   • First choice: Sacubitril/valsartan (ARNI) 49/51 mg twice daily, target 97/103 mg twice daily for NYHA class II-III 2
   • Alternative: ACEi (e.g., lisinopril 2.5-5 mg daily, target 20-40 mg daily) 2
   • If ACEi intolerant: ARB (e.g., candesartan 4-8 mg daily, target 32 mg daily) 2

2. Beta-blockers:

   • Cautiously initiate in hospital once patient is stabilized 1
   • Options: carvedilol 3.125 mg twice daily (target 25-50 mg twice daily), metoprolol succinate 12.5-25 mg daily (target 200 mg daily), or bisoprolol 1.25 mg daily (target 10 mg daily) 2
   • Do not abruptly withdraw beta-blockers as it can lead to clinical deterioration 2

3. Mineralocorticoid Receptor Antagonists (MRAs):

   • Spironolactone 12.5-25 mg daily (target 25-50 mg daily) or eplerenone 25 mg daily (target 50 mg daily) 2, 3
   • Indicated for all symptomatic patients with HFrEF and LVEF ≤35% 1
   • Monitor potassium and renal function closely 1

4. SGLT2 inhibitors:

   • Dapagliflozin or empagliflozin 10 mg daily 2
   • Consider initiating in-hospital for stabilized patients 1

Diuretic Management

• Loop diuretics: Furosemide 20-40 mg (oral or IV), adjust based on response and volume status 1
• For resistant edema, consider combination with thiazide diuretics (e.g., metolazone 2.5-10 mg) 1
• Goal: Achieve and maintain euvolemia with lowest effective dose 1
• Monitor: Daily weights, electrolytes, renal function 1

Special Considerations

Rate Control for Atrial Fibrillation

• Beta-blockers are first-line for rate control in HFrEF patients with AF 1
• Consider ivabradine for patients in sinus rhythm with heart rate ≥70 bpm despite maximum tolerated beta-blocker dose 4

Device Therapy Evaluation

• ICD: Consider for patients with LVEF ≤35% and NYHA Class II-III symptoms 2
• CRT: Consider for patients with LVEF ≤35%, QRS ≥150ms, and left bundle branch block morphology 2

Advanced Therapies for Refractory Cases

• Mechanical circulatory support
• Continuous intravenous positive inotropic therapy
• Evaluation for cardiac transplantation 2

Discharge Planning and Follow-up

1. Medication reconciliation - ensure all GDMT components are prescribed at appropriate doses
2. Patient education on:
   • Daily weight monitoring
   • Sodium restriction (<2-3g/day)
   • Fluid management
   • Medication adherence
   • Recognition of worsening symptoms
3. Early follow-up within 7-14 days of discharge
4. Continued uptitration of GDMT medications to target doses 2, 5

Common Pitfalls to Avoid

1. Underutilization of comprehensive GDMT - only 1% of eligible patients receive target doses of all recommended medications 2
2. Failure to initiate beta-blockers in-hospital after stabilization 1
3. Inadequate diuresis leading to persistent congestion 1
4. Abrupt withdrawal of beta-blockers during acute decompensation 2
5. Overlooking the importance of MRAs - they significantly reduce mortality (NNT=6 over 36 months) 2
6. Clinical inertia - many patients don't receive target doses for unknown reasons 5

Remember that optimization of all four pillars of GDMT (ARNI/ACEi/ARB, beta-blockers, MRAs, and SGLT2 inhibitors) has demonstrated significant mortality benefits in HFrEF patients 2, 6.