Assessment of systolic cardiac function by echocardiography revealed a marked reduction of the left ventricular ejection fraction in all mice 3, 6 and 9 weeks after TAC, but cardiac dysfunction was less pronounced in the AAV6 Musclin treated mice at all examined time points (Fig. 3f–h, Supplementary Table 1 showing additional echocardiographic parameters). This evidence concerns the gene OSTN and persistent truncus arteriosus.