Since the recent introduction of percutaneous balloon valvuloplasty, there has been a renewed interest in anatomical studies. This study was based on a retrospective analysis of 100 autopsy reports and 269 surgical reports from adult patients with AS. Valvular calcification, which was always found over the age of 50 years, plays an important part in the origin of aortic stenosis (AS). Congenital or acquired aortic valvular lesions are a common pre-condition for calcified AS. Three anatomical types were found: (i) calcified bicuspid valves with anterior and posterior cusps (more frequent than a left and a right cusp) were found in 41% of autopsy reports and 40% of surgical reports. The resultant rigidity due to calcification makes the valve stenotic; (ii) post rheumatic calcified AS with strong fusion of the commissures and calcified cusps was found in 30% of autopsy reports and 8% of surgery reports; and (iii) degenerative calcific aortic stenosis was the most frequent form found over 70 years of age. The sinuses of Valsalva were filled with calcium deposits. The three commissures were apparently free, but cusp fusion was found on the ventricular aspect of the valve (29% of autopsy cases and 52% of surgical reports). Percutaneous balloon valvuloplasty is more efficient in this anatomical type.