The first step in our research was the identification of all studies involving moderate AS. We observed that there are few studies that included ONLY patients with moderate AS. At the opposite, the large majority of studies included moderate AS among all spectrum of AS patients (sclerosis, mild, moderate, severe- alone or combined). That is why we categorized all previous studies regarding moderate AS by the baseline inclusion criteria. We found 4 major groups of enrolled patients that we reviewed and discussed below: patients with mild to moderate AS (Table 1) (5-10), patients with moderate AS (Table 2)(11-12), patients with mild, moderate and severe AS (Table 3)(13-20) and patients with moderate to severe AS (Table 4)(21-27).