Quadricuspid aortic valve (QAV) is an uncommon congenital anomaly. The majority of QAVs are associated with aortic insufficiency. QAVs usually have three cusps of equivalent size and a small fourth cusp between the right coronary cusp and the non‐coronary cusp. In this view the four leaflets are equivalent and the non‐coronary cusp is divided by a commissure.
The preoperative diagnosis of QAVs is important as they can be associated with an abnormally placed coronary ostium. Therefore preoperative coronary angiography is necessary when a QAV is diagnosed. The majority of QAVs are associated with clinically significant dysfunction, most commonly aortic insufficiency.
Aortic root: four equivalent leaflets.
The two non‐coronary cusps divided by a commissure (arrows).