Pathological Case of the Month

A 13-year-old Italian American boy complained of perceived episodes of rapid heart rate, which began during or immediately following exercise and subsided at rest. During these periods, he also experienced shortness of breath, diaphoresis, and dizziness without syncope. A grandfather died suddenly at the age of 40 years of unknown causes and a grandmother requires a pacemaker. The patient weighed 91 kg and his heart rate was 84 beats/min; a 12-lead electrocardiogram showed normal sinus rhythm with normal atrial and ventricular forces. An echocardiogram showed normal cardiac anatomy without any ventricular dyskinetic areas. Ventricular tachycardia was mapped by pace mapping and its origin was traced to the right ventricular outflow tract. The patient was given an event monitor (Figure 1). A right ventricular endomyocardial biopsy was performed (Figure 2).

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Diagnosis and Discussion

Arrhythmogenic Right Ventricular Dysplasia

Right ventricular dysplasia is an idiopathic cardiomyopathy¹ characterized pathologically by fatty infiltration