Amitriptyline-induced ventricular tachycardia: a case report

Area of Science:

• Cardiology
• Emergency Medicine
• Clinical Toxicology

Background:

• Amitriptyline overdose is a frequent challenge for emergency physicians in Bangladesh.
• Cardiovascular complications, particularly ventricular tachycardia, are major causes of mortality in tricyclic antidepressant overdose.
• Early identification and management are crucial for improving patient outcomes.

Observation:

• A 25-year-old female presented with impaired consciousness and wide complex tachycardia (QRS duration 178 ms) 10 hours after ingesting 2500 mg of amitriptyline.
• Initial treatment with sodium bicarbonate rapidly narrowed the QRS duration to 100 ms.
• Despite treatment, ST/T wave abnormalities persisted on electrocardiography at discharge.

Findings:

• Electrocardiography is vital for diagnosing and predicting complications of amitriptyline-induced ventricular tachycardia.
• Aggressive management with sodium bicarbonate (total dose 600 mmol over 24 hours) and intravenous lipid emulsion was employed.
• The patient's QRS duration normalized to 90 ms, and vital signs improved by discharge.

Implications:

• Diagnosis of amitriptyline-induced ventricular tachycardia can be challenging without a clear overdose history.
• Timely intervention utilizing electrocardiographic findings and appropriate medical therapies, including sodium bicarbonate and lipid emulsion, can be life-saving.
• This case highlights the importance of a structured approach to managing severe tricyclic antidepressant toxicity.