Long-term outcomes in 3 cases of quadricuspid aortic valve, using a new classification system: A case series and literature review.

Quadricuspid aortic valve has been classified based on leaflet size. However, no association is seen between classification and severity of aortic regurgitation (AR). Bicuspid aortic valve is classified according to the number of cusps, with significantly higher prevalence of AR in cases with a raphe. We classified cases according to raphe number. In 1 patient with no raphe, AR severity did not change into the eighth decade. However, AR severity worsened in patients with a raphe, in 1 case requiring aortic valve replacement in the fifth decade. Unequal shear stress may lead to leaflet fibrosis and progressive AR.