What is the pharmacotherapy for Acute Decompensated Heart Failure (ADHF)?

Pharmacotherapy for Acute Decompensated Heart Failure (ADHF)

Intravenous loop diuretics are the cornerstone of initial pharmacotherapy for ADHF, with vasodilators, inotropes, and vasopressors used based on hemodynamic status and clinical presentation. 1

Initial Assessment and Classification

When managing ADHF, treatment should be guided by the patient's hemodynamic profile:

• Congestion with adequate perfusion (most common): Diuretics + vasodilators
• Congestion with hypoperfusion: Inotropes + diuretics
• Cardiogenic shock: Vasopressors + inotropes + mechanical support consideration

First-Line Therapy: Diuretics

Loop Diuretics

• Initial dosing:

  • New-onset ADHF or diuretic-naïve: 20-40 mg IV furosemide (or equivalent) 1, 2
  • Chronic HF on oral diuretics: Initial IV dose should be at least equivalent to oral dose or doubled 1, 3
  • Maximum dose: 400-600 mg/day (up to 1000 mg/day in severe renal impairment) 3

• Administration method:

  • Either intermittent boluses or continuous infusion (both equally effective) 1, 3
  • Dose should be adjusted based on symptoms, clinical status, and urine output 1

• Monitoring:

  • Regular monitoring of symptoms, urine output, renal function, and electrolytes is mandatory 1
  • Target measures: Spot urinary sodium ≥50-70 mmol/L after 2 hours; urine output ≥100-150 mL/hour after 6 hours 3

Combination Diuretic Therapy

For diuretic resistance:

• Add thiazide diuretic (hydrochlorothiazide 25 mg) or spironolactone (25-50 mg) to loop diuretics 1
• Consider acetazolamide (500 mg IV daily) for first three days, especially with baseline bicarbonate ≥27 mmol/L 3

Second-Line Therapy: Vasodilators

• Indications: Symptomatic relief in ADHF with SBP >90 mmHg without symptomatic hypotension 1

• First choice in hypertensive ADHF to improve symptoms and reduce congestion 1

• Options:

  • Nitroglycerin: Preferred in ischemic conditions
  • Nitroprusside: Consider in patients with congestion and low cardiac output (use with caution if hypotensive) 4
  • Nesiritide: Alternative option based on renal function

• Monitoring: Frequent blood pressure and symptom monitoring during administration 1

Third-Line Therapy: Inotropes and Vasopressors

Inotropes

• Indications: Reserved for patients with hypotension (SBP <90 mmHg) with signs of hypoperfusion 1

• Options:

  • Dobutamine: First-line inotrope for most situations
  • Milrinone: Preferred in patients with significant pulmonary hypertension or those on beta-blockers 4
  • Levosimendan: Consider to reverse beta-blockade effects if contributing to hypotension 1

• Caution: Inotropes are NOT recommended unless the patient is symptomatically hypotensive or hypoperfused due to safety concerns (Class III, Level A) 1

Vasopressors

• Indications: Consider in cardiogenic shock despite inotrope therapy 1
• Preferred agent: Norepinephrine to increase blood pressure and vital organ perfusion 1
• Monitoring: ECG and blood pressure monitoring is mandatory; consider intra-arterial blood pressure measurement 1

Additional Pharmacotherapy

Opiates

• May be considered cautiously for severe dyspnea, restlessness, or anxiety 1
• Dosing: 2.5-5 mg IV morphine boluses 1
• Monitor for respiratory depression and nausea 1

Thromboembolic Prophylaxis

• LMWH recommended in patients not already anticoagulated and without contraindications 1

Chronic HF Medications

• Continue evidence-based disease-modifying therapies in the absence of hemodynamic instability 1
• Beta-blockers should be continued or reduced in dose but not typically discontinued 4

Special Considerations

Non-Invasive Ventilation

• Consider in patients with respiratory distress and pulmonary edema 1
• CPAP is feasible in pre-hospital settings; PS-PEEP preferred in hospital for patients with acidosis and hypercapnia 1

Mechanical Circulatory Support

• Consider early in patients who don't respond to initial medical therapy and are candidates for transplantation or LVAD 4

Common Pitfalls to Avoid

1. Overdiuresis: Can lead to hypotension, renal dysfunction, and electrolyte abnormalities
2. Underdiuresis: Results in persistent congestion and symptoms
3. Using inotropes in normotensive patients: Increases mortality risk
4. Discharging patients with residual congestion: Associated with poor outcomes and early readmission 3
5. Delaying diuretic administration: Door-to-diuretic time should not exceed 60 minutes 3

By following this algorithm and adjusting therapy based on clinical response, most patients with ADHF can be effectively managed with improved outcomes.