Magnetic Resonance Imaging and Computed Tomography Findings in Arrhythmogenic Right Ventricular Cardiomyopathy
A 56-year-old male patient presented with a 4-year history of recurrent palpitations. The initial ECG disclosed ventricular tachycardia with left bundle-branch block. Echocardiography showed a hypokinetic, enlarged right ventricle (RV) and right atrium. The left ventricle (LV) and atrium were normal in size, but LV function was moderately reduced at the apex in terms of hypokinesia.
Steady-state, free-precession cine sequences in the transverse and short-axis planes showed enlargement of the right atrium and RV and severe hypokinesia. The RV wall was thinned out and exhibited small, localized, outward bulges (Figure 1A and 1B; Movie I and Movie II in the online-only Data Supplement). On T1-weighted images, a linear, hyperintense structure inside the septum was visible, extending from the midseptum to the LV apex (Figure 2A). The structure could be clearly identified as a fatty infiltration of the myocardium by using fat suppression where the signal was hypointense (Figure 2B). On steady-state, free-precession images (Figure 1B), there was a signal void around the structure caused by a chemical shift. In addition, the corresponding computed tomography images displayed fat-equivalent Hounsfield units (−180 HU) (Figure 3). Another interesting finding was severe enhancement of the RV myocardium 15 minutes after administration of 1.0 mmol/kg body weight gadopentetate dimeglumine (late enhancement; Figure 4A and 4B). These changes extended to the left apex, suggesting LV involvement of the disease.
The online-only Data Supplement can be found with this article at http://circ.ahajournals.org/cgi/content/full/113/13/e673/DC1.