RIPK1 and Vascular dilatation: The relevance of these findings to aneurysm disease was further validated by the observation in the aneurysms that medial accumulation of macrophages coincides with SMC apoptosis, and that higher levels of RIP1/Caspase 8 containing cell death complexes are in vascular SMC-rich medial layer of injured arteries compared to that in control aortas.