ISSN: 1859 - 2872
Long QT syndrome type 2: A case of ventricular fibrillation and literature review
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Abstract
Congenital long QT syndrome (LQTS) is an important group of causes of syncope due to cardiac arrhythmias. We would like to report the case of a 33-year-old female with a history of syncope due to ventricular tachycardia and admitted to the hospital because of syncope. The corrected QT interval on the electrocardiogram was 567.9ms. Genetic testing detected a heterozygous variant in KCNH2 gene at chromosome 7 position 150947377 with variant NM_000238.4:c.3103del (NP_000229.1:p.Arg1035GlyfsTer22). The patient was diagnosed with long QT syndrome type 2 and classified as high risk group. The patient was initially still treated with propranolol but continued to have torsades de pointes, and then the patient was indicated with an implantable cardioverter defibrillator (ICD) to prevent sudden cardiac death. Genetic testing in cases of long QT syndrome is necessary for clear diagnosis and risk stratification. Indications for placement of an ICD should be considered in cases of patients with syncope due to ventricular arrhythmias to prevent sudden cardiac death in this group of diseases.
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References
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