Two Cases of Quadricuspid Aortic Valve

We report 2 cases (a 59-year-old man and a 61-year-old man) of quadricuspid aortic valve that had aortic regurgitation. Preoperative transthoracic or transesophageal echocardiography was useful for diagnosing definitely and deciding treatment plan. Their aortic valves were type F in each according to the Hurwitz-Roberts classification. They underwent aortic valve replacement and had good postoperative courses.