The Growth and Remodeling (G&R) processes in arterial wall have been widely studied over the past 20 years with a particular attention in their role on development of diseases such as aneurysm. The microstructure of arterial wall consists of different types of cells and extracel- lular matrix components, and, as most of the soft biological tissues, it maintains a specific pre- ferred mechanical state (mechanical homeostasis) . Computational constrained mixture models of growth and remodeling[1] have substantially contributed to the understanding of this com- plex phenomenon: when the tissue deviates from this homeostatic state, G&R processes, which refer to changes in mass and internal structure, help to restore homeostasis. Tissue remod- eling changes the orientational distribution of the collagen fibers through a continuous time- dependent degradation and deposition of tissue fibers. Starting from previous work in which the authors developed a statistical-based framework providing simple analytical solutions for understanding the evolution of collagen fiber distribution in soft tissues during G&R under uniaxial loading conditions [2], this study aims to apply the developed theoretical framework to investigate these phenomena in both healthy and aneurysmatic arterial wall. By using the homogenized constrained mixture theory [1, 3] and the concept of mechanical homeostasis, a probabilistic description of fiber-mass evolution law is formulated: since the collagen fibers are not aligned in a single direction, but rather their alignment is statistically distributed, the model accounts for a statistical distribution of collagen fibers [2] that is assumed to be characterized by a Von Mises-like probability distribution function, having the same mean value and vari- ance of the mass density distribution. The homogenized constrained mixture theory developed in [2] is applied to the G&R phenomena in both healthy and aneurysmatic arterial wall. once the evolution of the probability density function of the fibers during the remodeling process is achieved, it is possible to describe the crucial feature concerning the change of the architecture from physiological to pathological condition during the evolution of aneurysm. Preliminary numerical analysis show a good agreement with experimental data.