These animals developed typical features of pulmonary valve insufficiency-induced RV failure, such as progressive dilatation of the RV cavity, progressive deterioration of RV function, pathological hypertrophy, accumulation of interstitial fibrosis, disorganized myofilaments, mitochondrial dysfunction, and elevation of plasma NT-pro BNP levels. The gene discussed is NPPB; the disease is aortic valve insufficiency.