CONGENITAL LQTS – AN ELECTROCARDIOGRAPHIC AND GENOTYPE CORRELATION

Authors

  • Naveed Akhtar
  • Waqas Ahmed
  • Mehnaz Mehboob

Abstract

The congenital Long QT Syndrome (LQTS) is characterized by abnormally prolonged ventricularrepolarization due to inherited defect in cardiac sodium and potassium channels, whichpredisposes the patients to syncope, ventricular arrhythmias, and sudden cardiac death. Earlydiagnosis and preventive treatment are instrumental to prevent sudden cardiac death in patientswith the congenital LQTS. The diagnostic criteria for congenital LQTS are based on certainelectrocardiographic findings and clinical history. Recently genotype specific electrocardiographicpattern in the congenital LQTS has also been described. Recent studies suggest feasibility ofgenotype specific treatment of LQTS and, in near future, mutation specific treatment will probablybecome a novel approach to this potentially fatal syndrome. We describe two cases that fulfilledthe electrocardiographic and historical diagnostic criteria with morphology on electrocardiogram(ECG) suggestive of LQT1 genotype.Keywords: Congenital LQTS, ECG, genotype, pregnancy

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