Complete atrioventricular block-induced Torsade de pointes, manifested by epilepsy
Jun Han Jeon1, Sung Ho Her, Jung Yeon Chin
1Department of Internal Medicine, Daejeon St. Mary's Hospital, The Catholic University of Korea School of Medicine, Daejeon, Korea.
The Korean Journal of Internal Medicine
|March 26, 2011
Summary
Complete atrioventricular block can cause syncopal attacks. This case highlights Torsade de pointes, a complication of long QT interval, potentially induced by olanzapine, managed with a pacemaker.
Area of Science:
- Cardiology
- Clinical Electrophysiology
- Pharmacology
Background:
- Complete atrioventricular (AV) block can precipitate syncopal episodes, even with an escape rhythm.
- Torsade de pointes (TdP) is a critical complication associated with AV block and QT prolongation.
Observation:
- A 42-year-old female presented with recurrent seizure-like attacks, initially attributed to anti-convulsant use.
- Electrocardiogram (ECG) revealed Torsade de pointes with a significantly prolonged QT interval (QTc = 0.591 seconds).
- Olanzapine was identified as a potential causative agent, but symptoms persisted after discontinuation.
Findings:
- Despite stopping olanzapine, the patient exhibited persistent QT prolongation and recurrent TdP episodes with seizure-like symptoms.
- Implantation of a permanent pacemaker, maintaining a ventricular rate above 80 beats/min, effectively resolved the tachyarrhythmia.
- The patient experienced no further episodes of TdP or related symptoms post-pacemaker implantation.
Implications:
- This case underscores the potential for drug-induced QT prolongation and TdP in patients with AV block.
- Permanent pacemaker implantation can be an effective strategy for managing recurrent TdP and associated symptoms.
- Highlights the importance of vigilant cardiac monitoring in patients with risk factors for QT prolongation.
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