ELN and triple-A syndrome: Additionally, AAA formation is facilitated by the accumulation of oxidized low-density lipoprotein (LDL), which recruits and activates inflammatory cells, increases the expression of matrix metalloproteinases (MMPs), and subsequently lead to the degradation of elastin and apoptosis of smooth muscle cells (Figure 5), ultimately resulting in weakening and dilatation of the aortic wall (Kuivaniemi et al., 2015).