Case Report

Right Atrioventricular Valvular Dysplasia in a New Zealand White Rabbit

Figure 3

Gross image of the right atrial and ventricular lumina. The lumina of the right atrium and ventricle were markedly dilated as was the atrioventricular annulus. A fibrous ridge characterizes the annulus between the atrium and ventricle, and a single valve leaflet (free wall) is seen with a hypoplastic cusp (right arrow). The location of where the septal leaflet was expected (left arrow) has no leaflet (cusp aplasia) and no associated chordae tendineae. The chordae tendineae associated with the free wall leaflet were more characteristic of a thickened fenestrated membrane than individual well-developed chordae tendineae. The right wall thickness was within normal limits, but overall right heart mass was increased (eccentric hypertrophy). Inset: an image of an age-matched rabbit is provided for comparison.  cm.