Arrhythmogenic right ventricular dysplasia: MRI findings

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorde r of unknown cause that is characterized pathologically by fibrofatty repla cement of the right ventricular myocardium. Clinical manifestations include structural and functional malformations of the right ventricle, electracar diographic abnormalities, and presentation with ventricular tachycardias wi th left bundle branch pattern or sudden death. The disease is often familia r with an autosomal inheritance. In addition to right ventricular dilatatio n, right ventricular aneurysms are typical deformities of ARVD and they are distributed in the so-called "triangle of dysplasia", i.e., right ventricu lar outflow tract, apex, and infundibulum. Ventricular aneurysms at these s ites can be considered pathognomonic of ARVD. Another typical hallmark of A RVD is fibrofatty infiltration of the right ventricular free waif. These fu nctional and morphologic characteristics are relevant to clinical imaging i nvestigations such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and magnetic resonance imaging (MRI). Among these techniques, MRI allows the dearest visualization of the heart, in particular because the right ventricle is involved, which is usua lly more difficult to explore with the other imaging modalities Furthermore , MRI offers the specific advantage of visualizing adipose infiltration as a bright signal of the right ventricular myocardium, MRI provides the most important anatomic, functional, and morphologic criteria for diagnosis of A RVD within one single study. As a result, MRI appears to be the optimal ima ging technique for detecting and following patients with clinical suspicion of ARVD.