Korean Circ J.  2009 Sep;39(9):386-388. 10.4070/kcj.2009.39.9.386.

Epinephrine-Induced Polymorphic Ventricular Tachycardia in a Patient With Congenital Long QT Syndrome

• Kim JH
• Park SH
• Kim KH
• Choi WS
• Kang JK
• Kim NY
• Cho Y

• KMID: 2225676
• DOI: http://doi.org/10.4070/kcj.2009.39.9.386

Abstract

A 24-year-old woman presented to the department of plastic surgery for surgical excision of a nevus on her nose. Although her history failed to reveal any cardiac disease, her pre-operative electrocardiogram (ECG) showed an extremely prolonged QT interval of up to 528 msec. Repeated history-taking after admission revealed three syncopal episodes associated with both physical and emotional stress, and because the two-dimensional echocardiography and exercise ECG test were normal except for the prolonged QT interval, an epinephrine test was done to assess QT interval changes after an epinephrine infusion. Immediately after a bolus injection of epinephrine (0.1 microgram/kg), marked prolongation of the QT interval developed, followed by polymorphic ventricular tachycardia which was immediately terminated with direct current shock, resulting in the diagnosis of a long QT syndrome (LQTS), probably type 1. Gene studies were recommended, but declined by the patient and her family. She was instructed to avoid competitive sports, and a beta-blocker was prescribed after which she remained symptom-free.

Keyword

Long QT syndrome; Epinephrine; Ventricular tachycardia

MeSH Terms

Echocardiography
Electrocardiography
Epinephrine
Female
Heart Diseases
Humans
Long QT Syndrome
Nevus
Nose
Shock
Sports
Stress, Psychological
Surgery, Plastic
Syncope
Tachycardia, Ventricular
Young Adult
Epinephrine

Figure

• 

  Fig. 1 Routine ECG showing sinus rhythm with markedly prolonged QT (528 ms) and QTc (562 ms) intervals. ECG: electrocardiogram.

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  Fig. 2 Development of polymorphic ventricular tachycardia after a bolus injection of epinephrine.

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