Overview
Chronic Heart Failure
1. Overview
Heart Failure is a clinical syndrome where the heart cannot pump enough blood to meet metabolic needs (HFrEF) or cannot relax enough to fill (HFpEF). It is the only cardiovascular disease with increasing incidence.
Classification (LVEF based)
- HFrEF (Reduced Ejection Fraction): EF <40%. (Systolic Failure).
- HFmrEF (Mildly Reduced): EF 41-49%.
- HFpEF (Preserved Ejection Fraction): EF >50%. (Diastolic Failure).
Note: Treatment evidence is strongest for HFrEF.
2. Pathophysiology
- Insult: Ischemia (MI), Hypertension, or Alcohol damages muscle.
- Remodelling: Ventricle dilates and thins.
- Neurohormonal Activation (The Enemy):
- RAAS: Angiotensin II/Aldosterone increase fluid retention and fibrosis.
- Sympathetic (SNS): Adrenaline drives heart faster, toxic to myocytes.
- Neprilysin: Breaks down beneficial natriuretic peptides.
- Treatment Goal: Block RAAS, SNS, and Neprilysin.
3. Clinical Features
- Symptoms: Breathlessness (exertional), Orthopnea (pillows), Paroxysmal Nocturnal Dyspnea (PND), Fatigue, Ankle swelling.
- Signs:
- Tachycardia, Displaced Apex Beat.
- Fluid Overload: Elevated JVP, Bi-basal Crackles, Pitting Edema.
- S3: Third heart sound ("Gallop").
4. Diagnosis
Algorithm for New Breathlessness:
- Clinical History + Exam.
- NT-proBNP (Blood Test):
- Release by stretched ventricle. High in failure.
- <400: HF Unlikely.
- 400-2000: Refer for Echo (6 weeks).
- >2000: Urgent Echo (2 weeks).
- Echocardiogram (Gold Standard):
- Measures LVEF.
- Diagnostic for HFrEF vs HFpEF.
5. Management Algorithm (HFrEF)
The 4 Pillars of Guideline Directed Medical Therapy (GDMT). Evidence shows these drugs reduce mortality and hospitalization. Start ASAP.
┌─────────────────────────────────────────────────────────────────────────────┐
│ HFrEF MANAGEMENT PROTOCOL (<40%) │
├─────────────────────────────────────────────────────────────────────────────┤
│ SYMPTOM CONTROL │
│ • **Diuretics (Furosemide/Bumetanide)**: │
│ - Relieve congestion (edema/breathlessness). │
│ - NO survival benefit. Use lowest effective dose. │
│ └─────────────────────────────────────────────────────────────────────┘ │
│ ↓ │
│ PROGNOSTIC THERAPY (The 4 Pillars - Start all 4) │
│ │
│ 1. **ARNI (Sacubitril/Valsartan)** OR **ACE Inhibitor (Ramipril)** │
│ • ARNI (Entresto) is superior to ACEi (PARADIGM-HF). │
│ • Now often First Line. │
│ │
│ 2. **Beta Blocker** (Bisoprolol / Carvedilol) │
│ • Start low, go slow (don't decompensate fluid). │
│ • Target resting HR 60. │
│ │
│ 3. **MRA** (Spironolactone / Eplerenone) │
│ • Blocks Aldosterone fibrosis. │
│ • Monitor Potassium (Hyperkalemia risk). │
│ │
│ 4. **SGLT2 Inhibitor** (Dapagliflozin / Empagliflozin) │
│ • "The new statin for the heart". Massively reduces admission/death. │
│ • Safe even without diabetes. │
│ └─────────────────────────────────────────────────────────────────────┘ │
│ ↓ │
│ DEVICE THERAPY (If medical therapy fails & EF <35%) │
│ • **ICD**: Defibrillator (Secondary prevention of SCD). │
│ • **CRT-D**: Cardiac Resynchronization (Pacemaker to squeeze both sides │
│ together). Indicated if QRS is wide (LBBB). │
│ └─────────────────────────────────────────────────────────────────────┘
6. Management of HFpEF
- Traditionally "hard to treat".
- SGLT2 Inhibitors: The ONLY drug class proven to help HFpEF (EMPEROR/DELIVER trials).
- Diuretics for symptoms.
- Treat comorbidities (BP, AF, Obesity).
7. Complications
- Sudden Cardiac Death (SCD): Arrhythmia (VF/VT). Commonest cause of death.
- Pump Failure: Progressive decline.
- Renal Failure: Cardiorenal syndrome.
- Iron Deficiency: Treats with IV Iron (Ferric Carboxymaltose) improves symptoms.
8. Prognosis
- Rule of 50: 50% mortality at 5 years (Worse than many cancers).
- However, new drugs (4 Pillars) are significantly improving this.
9. Key Clinical Pearls
Exam-Focused Points
- Beta Blockers: NEVER start in acute pulmonary edema. Wait until "dry" (euvolemic).
- SGLT2i: The wonder drug. Works for HFrEF, HFpEF, and CKD.
- BNP: False lows in Obesity. False highs in AF/Age/CKD.
- Device criteria: EF <35% + Wide QRS (LBBB) = CRT.
- Spironolactone: Watch the Potassium. Gynecomastia side effect (switch to Eplerenone).
Common Exam Scenarios
- Patient with HFrEF on Ramipril, Bisoprolol. Still breathless. Next step? (Add Spironolactone or Dapagliflozin. Or switch Ramipril to Entresto).
- Patient takes Furosemide but ankles still swollen. (Check compliance, salt intake, or increase dose. Furosemide failure is common).
- 70yo with breathlessness, EF 60%. (HFpEF - Start Dapagliflozin).
10. Patient Explanation
Is my heart stopping?
"No. 'Failure' is a scary word, but it just means your pump is a bit weak. It's like an engine running on 3 cylinders instead of 4. With these medicines, we can strengthen the beat, take the strain off, and make the engine run efficiently for years."
Can I stop the water tablets?
"Only if your ankles are completely normal and your breathing is perfect. The water tablets don't fix the heart, they just clear the backlog of fluid. The other tablets (ACE/Beta-blocker) are the ones protecting the heart muscle itself."
11. Evidence & Guidelines
Key Guidelines
| Guideline | Organization | Year | Key Points |
|---|---|---|---|
| Heart Failure | ESC | 2021 | The 4 Pillars established. |
| Chronic HF | NICE (NG106) | 2018 | Diagnosis pathways. |
Evidence-Based Recommendations
| Recommendation | Evidence Level |
|---|---|
| SGLT2 Inhibitors | High (DAPA-HF, EMPEROR-Reduced) |
| ARNI (Entresto) | High (PARADIGM-HF) |
| CRT for LBBB >30ms | High |
13. References
- McDonagh TA, et al. 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur Heart J. 2021.
- McMurray JJ, et al. Dapagliflozin in patients with heart failure and reduced ejection fraction (DAPA-HF). N Engl J Med. 2019.