Figure 1.

The tracings shown were obtained from 4 different patients in the cohort. The tracing in (A) represents an ILR download from a patient with genotype‐positive catecholaminergic polymorphic ventricular tachycardia (CPVT). This event of polymorphic ventricular tachycardia occurred with activity (running), but the patient was asymptomatic with this event. In response to this event, the patient was started on nadolol. B, Represents a symptom event (chest pain) from a patient being treated with nadolol with genotype‐positive CPVT. The tracing demonstrates ventricular bigeminy followed by a bidirectional ventricular tachycardia, which then spontaneously terminates and returns to sinus rhythm with ventricular bigeminy. In response to this event, the patient was admitted for initiation of flecainide in addition to nadolol. C, Represents a patient with genotype‐positive CPVT who had a symptom event and a history of noncompliance with medication. This event of polymorphic ventricular tachycardia occurred during a time of emotional stress. Following this download, the patient underwent implantation of an automatic intracardiac defibrillator. The patient tracing in (D) is from a symptom event (chest pain, near syncope) in a patient with long QT syndrome who had just been jogging. He was being treated with betaxolol and was compliant with this medication. The tracing demonstrating sinus rhythm was reassuring that there was not an arrhythmic component to his symptoms. ILR indicates implantable loop recorder.