Lown-Ganong-Levine syndrome is an extremely rare conduction disorder characterized by a short PR interval (less than or equal to 120 ms) with normal QRS complex on electrocardiogram associated with the occurrence of episodes of atrial tachyarrythmias (e.g. atrial fibrillation, atrial tachycardia). The disease is MONDO_0007174 (Lown-Ganong-Levine syndrome). Also known as: LGL syndrome, atrial tachyarrhythmia with short PR interval, syndrome of short P-R interval, normal QRS complexes, and supraventricular tachycardias.