Septic Cardiomyopathy: Definition, Diagnosis & Management (ECMO Focus)
Overview & Impact
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Context: Common in ICU sepsis/septic shock; talk by an ECMO consultant (25–30 min).
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Incidence/Prevalence: Reported variably (10–70%) due to inconsistent definitions and criteria.
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Outcomes: When diagnosed, mortality increases 2–3×; not included in common ICU scores (SAPS, APACHE, SOFA).
Pathophysiology & Features
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Not CAD: Distinguished from atherosclerotic ischemia.
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Onset/Pattern: Acute, may be LV, RV, or biventricular.
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Proposed Mechanisms: Myocardial depressants/endotoxins, adrenergic hyperstimulation, myocardial edema (fluids), mitochondrial dysfunction, calcium dysregulation.
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Septic Shock Confounders: Altered preload/afterload/contractility, vasoactive drugs, organ supports (RRT, NO).
Diagnosis (Echocardiography-Centred)
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Primary Tool: Transthoracic echo preferred; TEE if needed.
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LV Systolic Function (beyond EF):
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LVOT VTI, TDI S′ (mitral annulus), MAPSE (>1.2 cm suggests normal EF).
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Global Longitudinal Strain (GLS): Around −20% indicates good contractility.
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Diastolic Function:
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TDI e′ (septal/lateral) for relaxation.
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E/e′ ratio (higher suggests elevated LV filling pressure).
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RV Assessment: TAPSE and RV FAC alongside TDI.
Why Patients Fare Poorly
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Host Factors: Older age, comorbidities, medications, sepsis/endocarditis, ischemia.
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Perioperative/ICU Factors: Inadequate myocardial protection, bleeding risk, vasoplegia, prolonged bypass (contextual).
Pharmacologic Management (Current Signals)
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Levosimendan: Mixed/negative data (including author’s ECMO-CRRT cohort and prior trials).
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Dobutamine: Can cause tachycardia/hypotension; limited benefit.
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Rate Control (Esmolol/Landiolol/Ivabradine): Conflicting RCT/meta-analytic results; no consistent outcome benefit.
Mechanical Circulatory Support (VA-ECMO)
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Rationale: Reversible acute failure; supports circulation while myocardium recovers.
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Evidence Highlights:
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Early single-centre data (small n) showed EF recovery.
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Multicentre controlled study (2020): In refractory septic cardiogenic shock (EF <35%), 90-day mortality lower with VA-ECMO (≈60% vs 25% control; significant).
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Meta-analyses/observational syntheses: ~37–42% survival in carefully selected patients; better when EF very low and selection is rigorous.
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Key Principle: Early identification, early referral, careful case-by-case selection (age, reversibility, echo profile).
Practical Takeaways
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Three Messages:
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Septic cardiomyopathy is common by day 3–4 of septic shock and raises mortality.
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Echo-led diagnosis using VTI, TDI (S′/e′), MAPSE, GLS, and RV indices—do not rely on EF alone.
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VA-ECMO can be life-saving in selected cases; apply individualized criteria and team review.
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Escalation Concept (Author’s Framework)
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Stepwise: Fluids/antibiotics → norepinephrine → (consider) beta-blockers/dobutamine/levosimendan (context-dependent) → VA-ECMO at the top for refractory septic cardiomyopathy.