<prompt> In a patient with history of recurrent syncope, Holter recording shows QT interval of 680msec. Which disease is suspected in this patient?Long QT syndromeBrugada syndromeArrhythmogenic RV dysplasiaLevs disease  <response>: 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: Levs disease characterized by fibrosis in conduction system, so will result in Bradyarrhythmia. 