Wave mice: a new tool in the quest to characterize aortic valvular disease etiologies

Although many patients with non-rheumatic aortic regurgitation (AR) are asymptomatic and do not require surgical intervention, chronic AR can lead to left ventricular (LV) hypertrophy and, eventually, heart failure (1). The progression from mild to chronic AR is poorly understood and relatively few animal models of chronic AR have been described. In a recent study published in Arteriosclerosis, Thrombosis, and Vascular Biology, Hajj et al. report the characterization of a “Wave” mouse model whose predominant valvular function abnormality is AR, despite the valves exhibiting many of the features traditionally associated with aortic stenosis (AS) (2). Unlike previously described models of AS (3,4), the valvular dysfunction exhibited by Wave mice is independent of the fibrocalcific changes found in the aortic valves of these mice. Thus, the results of this study challenge some of the current paradigms of aortic valve disease and are likely to impact pathophysiological conclusions related to both AR and AS.