Quadricuspid Aortic Valve: Report of Two Cases and Brief Review.

Quadricuspid aortic valve (QAV) is a rare congenital cardiac defect characterized by the presence of four aortic valve leaflets of equal or varying sizes. Even rarer is its clinical presentation with aortic stenosis. Diagnosis of QAV could be challenging but is of great importance as patients often present with progressive aortic regurgitation. We present 2 cases of QAV presenting differently: one with aortic stenosis requiring valve replacement and the other with aortic regurgitation requiring close monitoring