[A case of congenital long QT syndrome associated with T wave alternans]

Kokyu To Junkan. 1992 Feb;40(2):195-8.
[Article in Japanese]

Abstract

A case was presented in which a rare T wave alternans occurred in association with congenital long QT syndrome. A 71-year-old woman, who had experienced several syncopal attacks per year for the previous forty years, was admitted for further evaluation of the syncope. She had a family history of sudden death (sister) and QT prolongation (son). Electrocardiogram showed a corrected QT interval of 0.68 seconds. Treadmill exercise-tolerance test revealed both T wave alternans immediately after exercise and torsades de pointes 150 seconds after exercise. The syncope was induced by the mental excitation. A prolonged corrected QT interval reduced from 0.70 seconds to 0.58 seconds by the correction of her serum potassium and magnesium. The effect of propranolol, verapamil, phenytoin or mexiletine on T wave alternans and ventricular arrhythmia was evaluated by the treadmill exercise-tolerance test. The treatment with propranolol was most effective.

Publication types

  • Case Reports
  • English Abstract

MeSH terms

  • Adrenergic beta-Antagonists / therapeutic use
  • Aged
  • Electrocardiography*
  • Exercise Test
  • Female
  • Humans
  • Long QT Syndrome / congenital*
  • Long QT Syndrome / drug therapy
  • Long QT Syndrome / physiopathology
  • Propranolol / therapeutic use
  • Syncope / drug therapy
  • Syncope / etiology
  • Torsades de Pointes / drug therapy
  • Torsades de Pointes / etiology

Substances

  • Adrenergic beta-Antagonists
  • Propranolol