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Published on: January 16, 2019
Dilated cardiomyopathy masquerading as long QT syndrome
J Walls1, A Dipchand2, S Sanatani3
1Division of Cardiology, British Columibia Children's Hospital, Children's Heart Centre, 4480 Oak Street Vancouver, British Columbia, V6H 3V4, Canada.
Pediatric Cardiology
|January 5, 2006
Summary
Congenital long QT syndrome with atrioventricular block may precede dilated cardiomyopathy. This case highlights the need for close monitoring in affected infants due to potential evolving myocardial disease.
Area of Science:
- Pediatric Cardiology
- Electrophysiology
- Cardiomyopathy Research
Background:
- Congenital long QT syndrome (LQTS) is associated with an increased risk of mortality, particularly when accompanied by atrioventricular block.
- The interplay between LQTS, atrioventricular block, and the development of cardiomyopathy requires further elucidation.
Observation:
- An infant presented with congenital QT prolongation and atrioventricular block, initially diagnosed as LQTS.
- Initial cardiac function was normal, but the infant later developed dilated cardiomyopathy necessitating cardiac transplantation.
Findings:
- Electrocardiographic abnormalities, including QT prolongation and atrioventricular block, may represent early, preclinical signs of an underlying myocardial disease.
- The progression from electrocardiographic findings to overt cardiomyopathy occurred over several months.
Implications:
- Heightened surveillance is crucial for infants diagnosed with QT prolongation and atrioventricular block.
- Recognizing these ECG abnormalities as potential harbingers of evolving cardiomyopathy can guide timely intervention and management strategies.
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