LQT5
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Long QT Syndrome Microchapters |
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Diagnosis |
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Treatment |
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Case Studies |
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LQT5 On the Web |
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American Roentgen Ray Society Images of LQT5 |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]
Overview
LQT5 subtype of long QT syndrome is an autosomal dominant mutation that leads to a defect in the potassium channel. In its rare homozygous form it can cause Jervell and Lange-Nielsen syndrome.
LQT5 Subtype
| Type | OMIM | Mutation |
| LQT5 | 176261 | beta subunit MinK (or KCNE1) which coassembles with KvLQT1 |
Genetics and Pathophysiology
LQT5 is an autosomal dominant relatively uncommon form of LQTS. It involves mutations in the gene KCNE1 which encodes for the potassium channel beta subunit MinK. In its rare homozygous forms it can lead to Jervell and Lange-Nielsen syndrome. As in LQT1, LQT5 can lead to a decreased excretion of potassium from the cell and will show prolongation of the QT interval on EKG.
History and Symptoms
- Seizures - due to oxygen deprivation that occurs during arrhythmia.
- Fainting - fainting or syncope is the most common symptom LQTS.
- A prodrome may occur before losing consciousness, which may consist of lightheadedness, heart palpitations, blurred vision or weakness.
- Sudden death - a fatal arrhythmia that is not quickly intervened on, may cause sudden death.