Chymase inhibition attenuates cardiac fibrosis and dysfunction after myocardial infarction (Kanemitsu et al., 2006), progression to heart failure after autoimmune myocarditis (Palaniyandi et al., 2007), development of abdominal aortic aneurysm (Inoue et al., 2009), and interstitial fibrosis in renal obstruction (Fan et al., 2009) indicating that chymase is critical for fibrosis. Here, CMA1 is linked to abdominal aortic aneurysm.