Ventricular tachycardia during general anesthesia in a patient with congenital long QT syndrome

Congenital long QT syndrome is characterized by a corrected QT interval of at least 440 msec on the electrocardiogram and has been associated with recurrent syncope, documented ventricular arrhythmia and sudden death. There have been numerous articles over the past 20 years describing isolated instances of surgical and anesthesia related complications but the general anesthetic management of the condition remains unclear.

An 11-yr-old female with documented long QT syndrome, with two episodes of syncope in the past, was admitted for emergency drainage of left periorbital cellulitis. Anesthesia was induced with propofol, fentanyl and rocuronium, and initially maintained with nitrous oxide and halothane. After 20 min, the patient developed ventricular tachycardia (torsade de pointes). Lidocaine 1 mg.kg(-1) iv was given and the rhythm reverted to normal sinus. Halothane was discontinued and the surgery proceeded without further incident.

Our review of the literature revealed that patients with long QT syndrome whose symptoms are well controlled prior to surgery tend to do well regardless of the anesthetic chosen. There are, however, theoretical reasons to avoid anesthetics which either sensitize the myocardium to catecholamines or which cause an increase in circulating levels of catecholamines.