Arrhythmogenic Right Ventricular Dysplasia: MRI Findings

Abstract

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown cause that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. Clinical manifestations include structural and functional malformations of the right ventricle, electrocardiographic abnormalities, and presentation with ventricular tachycardias with left bundle branch pattern or sudden death. The disease is often familial with an autosomal inheritance. In addition to right ventricular dilatation, right ventricular aneurysms are typical deformities of ARVD and they are distributed in the so-called "triangle of dysplasia", i.e., right ventricular outflow tract, apex, and infundibulum. Ventricular aneurysms at these sites can be considered pathognomonic of ARVD. Another typical hallmark of ARVD is fibrofatty infiltration of the right ventricular free wall. These functional and morphologic characteristics are relevant to clinical imaging investigations such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and magnetic resonance imaging (MRI). Among these techniques, MRI allows the clearest visualization of the heart, in particular because the right ventricle is involved, which is usually 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 ARVD within one single study. As a result, MRI appears to be the optimal imaging technique for detecting and following patients with clinical suspicion of ARVD.

The value of magnetic resonance imaging for the diagnosis of arrhythmogenic right ventricular cardiomyopathy

“…The tree defines explicit diagnostic rules. Although both RV aneurysm and fatty tissue were found exclusively in ARVC patients in the present study, they are not considered pathognomonic [6,9]. There has been only little evidence of diagnostic importance of RV aneurysm in published reports.…”

“…The form of the curve indicates reliable classification model since both sensitivity and specificity are close to value 1. Also presented are sensitivity and specificity value pairs for different threshold values D (1)(2)(3)(4)(5)(6)(7)(8)(9).…”

“…During the past decade magnetic resonance imaging (MRI) has evolved as a noninvasive method with ability to image morphological, functional, and structural abnormalities of the RV [6,7]. Several studies have demonstrated a significant correlation between RV morphological abnormalities, visualized by MRI, and ventricular arrhythmias [8][9][10]. However, none of the single MRI findings is pathognomonic, and corresponding morphological abnormalities have also been identified in patients with idiopathic RV outflow tract tachycardia and healthy volunteers [11].…”

Decrease in Amplitude of Intracardiac Ventricular Electrogram and Inappropriate Therapy in Patients With an Implantable Cardioverter Defibrillator

“…Moreover, because the ventricular apex is one of the areas frequently involved in ARVC and sarcoidosis, lead replacement to another area might prevent the reappearance of decreasing R-waves. 17,18) However, the diseased right ventricular myocardium may prevent adequate lead replacement, and low R-wave may develop again. Limitations: The number of patients with each disorder was relatively small and our observations will need to be confirmed in a larger population, especially in patients with sarcoidosis, before they can be accepted as definitive.…”

Cardiovascular Magnetic Resonance Imaging in the Evaluation of the Right Ventricle and its Pathologies

“…15 As manifestações clínicas incluem principalmente taquicardias ventriculares com morfologia de bloqueio de ramo esquerdo do feixe de His e morte súbita. [14][15][16] A acurácia do exame de RMC na caracterização dessas alterações no VD e no estudo da sua função faz que esse seja o método de escolha na avaliação da DAVD, apresentando uma excelente acurácia diagnóstica e, também, melhor reprodutibilidade entre vários observadores experientes. 16,17 Tandri et al 17 demonstraram sensibilidade de 75% e especificidade de 97% no uso da RMC no estudo de anormalidades no movimento regional das paredes de VD, tendo, ao final, um valor preditivo positivo de 90% no estudo da doença.…”