Thiamine Cardiomyopathy (Cardiac Beriberi) 

Thiamine cardiomyopathy is a reversible cause of heart failure due to deficiency of vitamin B1 (thiamine). In ICU and emergency practice, it is crucial because:

• It mimics septic shock
• It mimics dilated cardiomyopathy
• It may present as refractory lactic acidosis
• It dramatically improves within hours after IV thiamine

Why Is It Called “Beri-Beri”?

The term “beriberi” comes from the Sinhala language of Sri Lanka.

In Sinhala, “beri”  means:

“I cannot” or “weakness” .When repeated — “beri-beri” — it conveys:

“I cannot, I cannot”

This describes the profound muscle weakness and fatigue seen in thiamine deficiency.

Historical Context

• The disease was common in 19th-century Sri Lanka and Southeast Asia.
• It was strongly associated with populations consuming polished white rice.
• Milling removes the thiamine-rich outer husk (bran layer).
• As polished rice consumption increased, beriberi epidemics appeared.

Later, in the late 19th century, researchers like Christiaan Eijkman demonstrated that polished rice caused a deficiency disease in chickens, leading to the discovery of vitamin B1 (thiamine).

ICU Clinical Scenario

A malnourished alcoholic presents with:

• Hypotension
• Lactate 8 mmol/L
• EF 25%
• No infection source

Given IV thiamine → lactate drops to 3 mmol/L in 12 hrs → BP improves.

Diagnosis: Shoshin Beriberi

1. Thiamine: Biochemical Foundation

Thiamine (Vitamin B1) is converted to Thiamine Pyrophosphate (TPP), a cofactor for:TCA cycle,Amino acid metabolism,Pyruvate dehydrogenase

Core Concept:

Thiamine deficiency → impaired aerobic metabolism → ↓ ATP → ↑ lactate → myocardial energy failure.

2. Causes of Thiamine Deficiency (ICU-Relevant)

1. Chronic alcoholism

Commonest cause.

2. Malnutrition

• Cancer
• Chronic illness
• Elderly
• Post bariatric surgery

3. Prolonged parenteral nutrition without supplementation

4. Dialysis patients

5. Sepsis (increased utilization)

6. Hyperemesis gravidarum

3. Pathophysiology of Thiamine Cardiomyopathy

Stepwise Mechanism:

1. Impaired PDH activity
2. Pyruvate accumulates → converts to lactate
3. Cellular ATP falls
4. Myocardial contractility declines
5. Peripheral vasodilation develops
6. Neurohormonal activation (RAAS, SNS)
7. High-output heart failure → later low-output failure

4. Clinical Presentation

Early

• Fatigue
• Dyspnea
• Tachycardia
• Peripheral edema

Advanced

• Cardiomegaly
• Hypotension
• Pulmonary edema
• Lactic acidosis
• Shock

Associated Findings

• Peripheral neuropathy
• Wernicke encephalopathy

5. Types of Cardiac Beriberi

A. Wet Beriberi (Classic Form)

• Peripheral edema
• Tachycardia
• Wide pulse pressure
• Warm extremities
• High-output cardiac failure

B. Shoshin Beriberi (Fulminant Form)

“Shoshin” = acute, severe, rapidly fatal form.

Features:

• Severe hypotension
• Cardiogenic shock
• Severe lactic acidosis
• Rapid collapse
• Multiorgan failure

ICU pearl:
Refractory shock + high lactate + malnourished patient → Give thiamine immediately.

5. Hemodynamic Profile

Mechanism of high-output state:

• Peripheral vasodilation due to metabolic failure
• Reduced SVR → compensatory tachycardia

7. Echocardiography Findings

• Dilated LV
• Global hypokinesia
• Reduced EF
• No coronary artery disease

Important: Reversible after thiamine therapy

8. Laboratory Features

RBC Transketolase Activity

Gold standard (rarely available)

9. Diagnostic Clue in ICU

The most important diagnostic tool:

Therapeutic trial of IV thiamine

If:

• Lactate decreases within 12–24 hrs
• BP improves
• Inotrope requirement falls

→ Diagnosis strongly supported.

10. Management (Guideline-Oriented Critical Care Approach)

1. Immediate Thiamine

• 100–200 mg IV stat
• Severe shock: 200–500 mg IV TDS
• Continue for 3–5 days
• Then oral 100 mg/day

Always give thiamine before glucose in malnourished patients

Why?
Glucose infusion increases pyruvate → worsens lactic acidosis.

2. Heart Failure Management

• Oxygen
• Diuretics
• Vasopressors (if shock)
• Inotropes if low EF

But dramatic response often seen after thiamine.

11. Differential Diagnosis