Arrhythmogenic right ventricular cardiomyopathy/dysplasia

Abstract

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is characterized by the patchy replacement of myocardium by fatty or fibrofatty tissue. These changes lead to structural abnormalities including right ventricular enlargement and wall motion abnormalities that can be detected by echocardiography, angiography, and cine MRI. ARVC/D is a genetically heterogeneous disorder, since it has been linked to several chromosomal loci. Myocarditis may also be a contributing etiological factor. Patients are typically diagnosed during adolescence or young adulthood. Presenting symptoms are generally related to ventricular arrhythmias. Concern for the risk of sudden cardiac death may lead to the implantation of an intracardiac defibrillator. An ongoing multicenter international registry should further our understanding of this disease.

Figure 1

In ARVC/D there is progressive fibro-fatty replacement of the myocardium with thinning and enlargement of the RV wall. In this specimen there is gross fatty infiltration seen in a portion of the RV wall.

Figure 2

Trichrome staining shows areas of mature fibrosis (F) and adipose tissue (A) within the epicardial (Epi) and mid-myocardial zones, with remaining small clusters of myocytes (Myo) near the endocardial edge (Endo).

Figure 3

This ECG from a patient with ARVC/D shows T wave inversion throughout the precordial leads.

Figure 4

Epsilon waves, representing right ventricular late potentials, can be brought out by recording the ECG at double speed (50mm/s), double amplitude (20mm/mV), and a 40 Hz filter. Here, epsilon waves are evident as small, notched deflections just after the QRS in lead V1 (arrows).