What is the difference between acute and chronic heart failure in terms of treatment approaches?

Acute vs Chronic Heart Failure: Treatment Approach Differences

The fundamental difference in treatment approach is that acute heart failure requires immediate hemodynamic stabilization with IV diuretics, oxygen, and vasodilators to relieve life-threatening congestion and hypoperfusion, while chronic heart failure management focuses on long-term disease-modifying therapies (ACE inhibitors, beta-blockers, MRAs, ARNI) to prevent progression and reduce mortality. 1

Defining the Two Entities

Acute Heart Failure (AHF)

• Rapid onset or change in symptoms and signs requiring urgent medical attention and usually hospital admission 1
• Includes two distinct presentations:
  • De novo AHF: First presentation of heart failure with no prior diagnosis 1, 2
  • Acutely decompensated chronic HF (ADCHF): Worsening of pre-existing chronic heart failure 1, 3
• Timeline varies from minutes to hours (e.g., acute MI) or days to weeks (progressive congestion) 1
• Spectrum ranges from life-threatening pulmonary edema/cardiogenic shock to predominantly peripheral edema 1

Chronic Heart Failure (CHF)

• Stable, ongoing condition managed in outpatient settings with established disease-modifying therapies 4
• Characterized by persistent structural or functional cardiac abnormalities 1
• Classified by ejection fraction: HFrEF (≤40%), HFmrEF (41-49%), HFpEF (≥50%) 1

Treatment Approach for Acute Heart Failure

Immediate Assessment Priorities

Three parallel assessments must occur simultaneously 1:

1. Confirm HF diagnosis vs alternative causes (COPD, anemia, pulmonary embolism, renal failure)
2. Identify precipitants requiring immediate correction (arrhythmia, acute coronary syndrome, infection, medication non-adherence, NSAIDs, uncontrolled hypertension) 1
3. Assess life-threatening status: hypoxemia or hypotension causing vital organ underperfusion (heart, kidneys, brain)

Acute Pharmacological Management

IV Loop Diuretics - Cornerstone of acute treatment 1, 4:

• Initial dose: 20-40 mg IV furosemide for new-onset AHF; at least equivalent to oral dose for those on chronic diuretics 1
• Administer as intermittent boluses or continuous infusion 1
• Monitor continuously: symptoms, urine output, renal function, electrolytes 1
• High-dose strategy (2.5× previous oral dose) provides greater dyspnea improvement but may transiently worsen renal function 1

Oxygen Therapy 1:

• Give only for hypoxemia (SpO2 <90%) - associated with increased short-term mortality
• Do not use routinely in non-hypoxemic patients (causes vasoconstriction and reduced cardiac output)

Vasodilators 1:

• Key drug alongside oxygen and diuretics
• Particularly useful in hypertensive heart failure presentations 1

Inotropes 1:

• Not recommended unless symptomatic hypotension or hypoperfusion present (safety concerns)
• Use selectively only in specific hemodynamic scenarios

Critical Monitoring

• Continuous assessment of: systolic blood pressure, heart rhythm/rate, SpO2, urine output 1
• Some patients require intensive or coronary care unit management 1

Treatment Approach for Chronic Heart Failure

Disease-Modifying Pharmacotherapy for HFrEF

Foundational Quadruple Therapy 4:

1. ACE Inhibitors (or ARB if intolerant):

   • Start immediately in all reduced LVEF patients 4
   • Begin low dose, titrate to target maintenance doses proven in trials 4
   • Prevents HF onset and prolongs life in asymptomatic LV dysfunction post-MI 1

2. Beta-Blockers:

   • Add for all stable HFrEF patients (NYHA II-IV) already on ACE inhibitors and diuretics 4
   • Prevents HF onset in asymptomatic LV dysfunction post-MI 1

3. Mineralocorticoid Receptor Antagonists (MRAs):

   • Add if symptoms persist despite ACE inhibitor and beta-blocker 4

4. Sacubitril/Valsartan (ARNI):

   • Replace ACE inhibitor in patients remaining symptomatic despite optimal therapy 4
   • Mandatory 36-hour washout when transitioning from ACE inhibitors (angioedema risk) 5

Diuretics:

• Use when fluid overload present (pulmonary congestion, peripheral edema) 4
• Not disease-modifying but essential for symptom control

Device Therapy for HFrEF

Implantable Cardioverter-Defibrillators (ICDs) 4:

• Symptomatic HF (NYHA II-III), LVEF ≤35%, optimal medical therapy ≥3 months
• Reduces sudden death and all-cause mortality

Cardiac Resynchronization Therapy (CRT) 1, 4:

• Sinus rhythm, QRS ≥150 msec, LBBB morphology, LVEF ≤35% despite optimal medical therapy (Class I/A) 1
• QRS ≥130 msec with LBBB (Class I/B) 1

Management for HFpEF

First-line approach 5:

• Risk factor management (hypertension, diabetes, obesity, atrial fibrillation)
• Symptom control with diuretics

Evidence-based therapies 5:

• SGLT2 inhibitors (dapagliflozin, empagliflozin) - significant benefits, consider early
• MRAs (spironolactone) - for selected patients with elevated natriuretic peptides or recent hospitalization
• Sacubitril/valsartan - consider for symptomatic patients with EF 45-57%, particularly women 5

Critical Distinction in Management Philosophy

During Acute Decompensation

Continue chronic disease-modifying therapies unless hemodynamic instability or contraindications present 1. The immediate goals are symptom improvement and hemodynamic stabilization, but longer-term management including post-discharge care is equally important to prevent recurrences and improve prognosis 1.

Post-Discharge Transition

Pre- and post-discharge care should follow chronic HF management recommendations 1. Worsening HF events are opportunities to optimize proven therapies rather than reasons to discontinue them 6.

Common Pitfalls to Avoid

• Do not use oxygen routinely in non-hypoxemic AHF patients 1
• Avoid inotropes unless clear hypotension/hypoperfusion 1
• Do not discontinue disease-modifying drugs during acute decompensation unless hemodynamically unstable 1
• Recognize that ADCHF carries worse long-term prognosis than de novo AHF (58% higher 1-year mortality, 48% higher 10-year mortality) despite similar 30-day outcomes 7
• NSAIDs and certain antibiotics are nephrotoxic and should be avoided in HF patients with worsening renal function 1
• Thiazide diuretics less effective with very low eGFR 1

Non-Pharmacological Management (Chronic HF)

• Daily weight monitoring with weight log 4
• Sodium restriction to 2-3 grams daily, particularly in severe HF 4
• Regular aerobic exercise to improve functional capacity, symptoms, and reduce HF hospitalization risk (HFrEF) 1
• Multidisciplinary care management program enrollment to reduce HF hospitalization and mortality 1