On one hand, TLR9 deficiency could improve cardiac function and suppress myocardial necrosis and inflammation.558 On the other hand, TLR9 knockout mice show higher rates of cardiac rupture and mortality after MI, likely due to reduced myofibroblasts, impaired matrix production, increased apoptosis and reduced angiogenesis.555. This evidence concerns the gene TLR9 and myocardial infarction.