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Published on: June 20, 2020
An elderly woman with bradycardia and progressive repolarization abnormalities
Kapil Rajendran1, Arun Jude Alphonse1, Vinayakumar Desabandhu2
1Department of Cardiology, Government TD Medical College Alappuzha, Kerala, India.
Cardiac memory, a phenomenon where the heart adapts to pacing, can cause dangerous T-wave changes and QTc prolongation. This case underscores its proarrhythmic potential in bradyarrhythmia, necessitating vigilant ECG monitoring.
Area of Science:
- Cardiology
- Electrophysiology
- Internal Medicine
Background:
- Complete heart block can lead to cardiac arrest.
- Cardiac memory is a phenomenon where the heart's electrical activity adapts to pacing.
- Repolarization abnormalities can increase the risk of ventricular arrhythmias.
Purpose of the Study:
- To report a case of cardiac arrest due to complete heart block.
- To highlight the role of cardiac memory in developing repolarization abnormalities.
- To emphasize the importance of serial ECG monitoring in managing bradyarrhythmia.
Main Methods:
- Case report of an elderly woman with complete heart block.
- Electrocardiogram (ECG) monitoring to assess repolarization changes.
- Coronary angiography to rule out obstructive coronary artery disease.
Main Results:
- The patient developed progressive T-wave inversions (V3-V6) and QTc prolongation due to pacing-induced cardiac memory.
- These repolarization abnormalities occurred despite normal electrolytes and non-obstructive coronary angiography.
- The patient experienced polymorphic ventricular tachycardia.
Conclusions:
- Cardiac memory can be an underrecognized proarrhythmic substrate in patients with bradyarrhythmia.
- Serial ECG monitoring is crucial for detecting evolving repolarization changes.
- Early detection and management of repolarization abnormalities can mitigate arrhythmic risk.
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