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Torsade de pointes and syncopal attacks in a 26-year old woman with congenital complete heart block and prolonged QT

D K Quek1, S B Ong

  • 1Department of Medicine, National University of Malaysia, Kuala Lumpur.

Singapore Medical Journal
|April 1, 1990
PubMed

Insights

Congenital complete heart block with prolonged QT interval can cause dangerous Torsade de Pointes in adulthood. Early recognition and treatment with beta-blockade and pacing can prevent life-threatening arrhythmias.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Genetics

Background:

  • Congenital complete heart block (CCHB) is a rare condition often associated with prolonged QT interval.
  • Patients with CCHB may present with syncope and ventricular arrhythmias in adulthood.

Observation:

  • A 26-year-old woman with CCHB and prolonged QT experienced syncopal attacks due to Torsade de Pointes (TdP).
  • Ambulatory ECG monitoring revealed TdP episodes leading to ventricular flutter during periods of pacemaker non-capture.

Findings:

  • Cardioversion and overdrive pacing were initially required to manage the unstable cardiac rhythm.
  • Combined therapy with beta-blockade and permanent ventricular pacing successfully eliminated syncopal episodes and TdP.

Implications:

  • The prognosis of CCHB with QT prolongation is similar to Romano-Ward syndrome.
  • Recognizing this variant of CCHB allows for earlier diagnosis and treatment of this potentially fatal disorder.

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