Prolonged QT interval on electrocardiogram and fainting — is there always a relationship?
- Authors: Mishanina Y.S1, Oslopov VN1, Oslopova Y.V2, Teregulov Y.E1, Khazova EV1
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Affiliations:
- Kazan State Medical University
- Kazan (Volga Region) Federal University
- Issue: Vol 102, No 5 (2021)
- Pages: 747-750
- Section: Clinical observations
- Submitted: 23.04.2021
- Accepted: 25.04.2021
- Published: 13.10.2021
- URL: https://kazanmedjournal.ru/kazanmedj/article/view/65296
- DOI: https://doi.org/10.17816/KMJ2021-747
- ID: 65296
Cite item
Abstract
Using a clinical example, the article draws the attention of doctors to the problem of the prolonged QT interval (“long QT”) and the related problem of fainting (syncope). Syncope is a component of long QT syndrome, and syncope is a precursor of sudden cardiac death. However, syncope in a patient with long QT syndrome may have pathogenesis that is completely unrelated to abnormalities of cardiac ion channels. In other words, such a patient may have a second disease as a syntropy relates to prolonged QT interval, to an extent mimicking long QT syndrome. The presented medical history of a 33-year-old patient S. shows the complexity of differential diagnosis of the causes of syncope. The crucial part in the diagnosis, in addition to the clinical picture, was the so-called “tilt test”, little-known to general medical practice, as well as the laboriousness of making a final diagnosis of the long QT Syndrome type 2, which required a molecular genetic study — whole-exome sequencing. Patient S. had vasovagal syncope that not associated with long QT syndrome, but she has a risk of sudden cardiac death, and the article identifies therapeutic and other measures to reduce this risk.
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About the authors
Yu S Mishanina
Kazan State Medical University
Author for correspondence.
Email: mishanina.1998@list.ru
Russian Federation, Kazan, Russia
V N Oslopov
Kazan State Medical University
Email: mishanina.1998@list.ru
Russian Federation, Kazan, Russia
Yu V Oslopova
Kazan (Volga Region) Federal University
Email: mishanina.1998@list.ru
Russian Federation, Kazan, Russia
Yu E Teregulov
Kazan State Medical University
Email: mishanina.1998@list.ru
Russian Federation, Kazan, Russia
E V Khazova
Kazan State Medical University
Email: mishanina.1998@list.ru
Russian Federation, Kazan, Russia
References
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