In a patient with history of recurrent syncope, Holter recording shows QT interval of 680msec. Which disease is suspected in this patient?: (A) Long QT syndrome, (B) Brugada syndrome, (C) Arrhythmogenic RV dysplasia, (D) Lev's disease
Answer is A. Normal QT interval= 360-440 msec. Option A: QT interval prolonged- predisposes to Torsades de Pointes , so Dx of this is Long QT syndrome. Option B: Channel defect (SCN5A defect) in hea-->depolarization is defective -->defective development of voltage gradient leads to arrhythmia which result in Brugada syndrome. Option C: ARVD is fibrofatty deposition in RV epicardium & in ECG presence of Epsilon wave Option D: Lev's disease characterized by fibrosis in conduction system, so will result in Bradyarrhythmia.