Curriculum in CardiologyLong QT syndrome: Diagnosis and management☆
Section snippets
Diagnosis of LQT syndrome
The diagnosis of LQT primarily depends on the clinical features, the family history, and the ECG findings of the patient. Unexplained syncope or sudden cardiac death in a child or young adult should raise a high suspicion of the possibility of presence of LQT. Electrophysiologic testing is not helpful in making the diagnosis of LQT. Genetic testing has not become a routine part of the diagnostic workup in patients with LQT, although it could be of assistance in the borderline cases or in cases
Short-term treatment
Immediate cardioversion should be done in situations where torsades does not terminate spontaneously and results in hemodynamic compromise. The short-term treatment, which is aimed at prevention of the recurrences of torsades, includes withdrawal of the offending agents, correction of the underlying electrolyte abnormalities, and administration of magnesium, potassium, temporary transvenous cardiac pacing, and rarely intravenous isoproterenol. The magnesium, potassium, and temporary transvenous
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Reprint requests: Ijaz A. Khan, MD, FACP, FACC, Creighton University Cardiac Center, 3006 Webster St, Omaha, NE 68131-2044. E-mail: [email protected]