- Exercise-related syncope is also found in LQT syndrome. LQT syndrome can be present inpatients with normal QT interval.- Andersen-Tawil syndrome (ATS) is an inherited arrhythmogenic disorder caused by mutations inthe KCNJ2 gene and characterized by QT prolongation and distinctive facial features. Patientswith this condition may also develop bidirectional VT- Coronary abnormalities, ARVD and hypertrophic cardiomyopathy might present with similarsymptoms. The underlying structural heart disease can be subtle, therefore adequate imagingshould be included in the workup.