Use of Advanced Cardiac Imaging in the Diagnosis of Arrhythmogenic Right Ventricular Cardiomyopathy

Abstract

A 22-year-old male student presented to his general practitioner with chest discomfort and palpitations. There were no exertional symptoms or syncope and no family history of cardiac disease or sudden death. Cardiovascular examination was unremarkable. Echocardiogram demonstrated sinus bradycardia with epsilon waves in the inferior leads and abnormal T-wave morphology in the anterior leads. Seven beats of non–sustained ventricular tachycardia and frequent ventricular ectopy were present during cardiac monitoring. Transthoracic echocardiography demonstrated a dilated, dyskinetic right ventricle (RV) with systolic impairment (Figure 1) and impaired RV ventricular strain (Figure 2). There was mildly reduced left ventricular (LV) systolic function (LV ejection fraction 52%). Computed tomography coronary angiogram established normal coronary anatomy. Cardiac magnetic resonance imaging revealed segmental LV and RV dysfunction with regional fibrosis in both ventricles, predominantly affecting the right (RV ejection fraction 37%). There was severe dilatation of the RV (end diastolic volume 156 mL/m2; (Figure 3). The mid-inferior, mid-distal RV free wall, and RV outflow tract were akinetic. Post–gadolinium delayed enhancement was consistent with a non–ischaemic aetiology. The main differentials were arrhythmogenic right ventricular cardiomyopathy and cardiac sarcoidosis, the latter was excluded with a negative positron emission tomography scan. A subcutaneous implantable defibrillator was implanted for primary prevention of sudden cardiac death and the patient was started on ramipril 2.5 mg and bisoprolol 1.25 mg. He is being followed-up regularly and remains well. Proband genetic testing and family screening of first-degree relatives for arrhythmogenic right ventricular cardiomyopathy has been advised. This case illustrates the incremental value of multimodality imaging in the diagnosis of this rare but potentially life-threatening condition. Figure 2 View Large Image Figure Viewer Download Hi-res image Figure 3 View Large Image Figure Viewer Download Hi-res image