Levosimendan
1. Introduction
Levosimendan is a calcium sensitizer + inodilator used in acute decompensated heart failure (ADHF) and selected cardiogenic shock states.
- Unlike catecholamines, it improves contractility without increasing intracellular Ca²⁺
- Produces inotropy + vasodilation (inodilator)
- Has prolonged action due to active metabolites
2. Mechanism of Action
A. Calcium Sensitization
- Binds to troponin C
- Enhances actin–myosin interaction
- No increase in intracellular Ca²⁺ → no increase in myocardial oxygen consumption
Key exam point:
✔ Improves contractility without tachycardia or increased O₂ demand
B. KATP Channel Opening
- Opens ATP-sensitive K⁺ channels
- Vascular smooth muscle → vasodilation
- Mitochondria → cardioprotection
C. Net Hemodynamic Effects
|
Effect |
Mechanism |
|
↑ Cardiac output |
Positive inotropy |
|
↓ SVR |
Vasodilation |
|
↓ Preload |
Venodilation |
|
↓ Pulmonary pressures |
Pulmonary vasodilation |
3. Pharmacokinetics
|
Parameter |
Value |
|
Route |
IV infusion |
|
Onset |
Within minutes |
|
Half-life (parent drug) |
~1 hour |
|
Active metabolite (OR-1896) |
Half-life ~70–80 hours |
|
Duration of action |
Up to 7–10 days |
✔ Effects persist even after stopping infusion
4. Indications in ICU
A. Acute Decompensated Heart Failure (ADHF)
- Especially:
- Low cardiac output
- Beta-blocker use (catecholamine-resistant)
B. Cardiogenic Shock (Selected cases)
- Not first-line
- Consider when:
- Poor response to noradrenaline/dobutamine
- Need to avoid tachyarrhythmia
C. Right Ventricular Failure
- Pulmonary vasodilation + RV contractility improvement
D. Weaning from VA-ECMO
- Improves myocardial recovery
5. Dose & Administration
Standard Regimen
- Loading dose: 6–12 µg/kg over 10 min (often avoided in ICU)
- Infusion: 0.05–0.2 µg/kg/min for 24 hours
ICU practice:
- Avoid bolus → prevents hypotension
- Start low dose (0.05–0.1 µg/kg/min)
6. Hemodynamic Profile vs Other Inotropes
|
Drug |
Inotropy |
Vasodilation |
HR effect |
O₂ demand |
|
Dobutamine |
↑↑ |
↑ |
↑↑ |
↑ |
|
Milrinone |
↑↑ |
↑↑ |
↑ |
↑ |
|
Levosimendan |
↑↑ |
↑↑ |
Minimal |
↔ |
Unique advantage:
✔ No significant increase in myocardial oxygen consumption
7. Advantages
- Works independent of β-receptors
- Effective in patients on beta-blockers
- No tachyphylaxis
- Prolonged action
- Improves:
- Cardiac output
- Renal perfusion
- Pulmonary pressures
8. Adverse Effects
Common
- Hypotension (most important)
- Headache
- Nausea
Serious
- Arrhythmias (less than catecholamines)
- Hypokalemia
Key point:
✔ Hypotension limits use in shock
9. Contraindications
- Severe hypotension
- Severe hypovolemia
- Significant arrhythmias
- Severe renal/hepatic failure (caution due to metabolite accumulation)
10. Evidence & Trials
A. SURVIVE Trial
- Compared levosimendan vs dobutamine
- No mortality benefit
- Better hemodynamics
B. REVIVE Trials
- Symptom improvement
- More hypotension and arrhythmias
C. CHEETAH Trial (Cardiac surgery)
- No mortality benefit
11. Guideline Recommendations
European Society of Cardiology (ESC HF Guidelines)
- May be considered in:
- ADHF with low output
- Especially on β-blockers
- Not first-line in cardiogenic shock
American Heart Association / American College of Cardiology
- Limited recommendation
- Not routine first-line
- Consider as adjunct in refractory cases
12. Comparison with Milrinone
|
Feature |
Levosimendan |
Milrinone |
|
Mechanism |
Ca sensitizer |
PDE-3 inhibitor |
|
β-receptor dependence |
No |
No |
|
Hypotension |
Moderate |
Significant |
|
Duration |
Very long |
Short |
|
Arrhythmia risk |
Less |
More |
13. Special ICU Situations
A. Septic Cardiomyopathy
- Mixed evidence
- Not routine
B. Cardiorenal Syndrome
- Improves renal perfusion via:
- Increased CO
- Renal vasodilation
C. Pulmonary Hypertension
- Useful due to pulmonary vasodilation
