这是一个先天性的两瓣叶主动脉瓣。大部分瓣叶容易钙化。病人无明显症状，这种状况可持续至狭窄发展到充血性心力衰竭的时候。在瓣膜的表面可见密集的白色钙化灶。这里的瓣膜已经通过主动脉流出道之上和左心室以下切开了。
Here is a congenital bicuspid aortic valve. Most bicuspid valves are prone to calcification. Patients can remain relatively asymptomatic until the stenosis reaches a critical point when congestive heart failure rapidly ensues. The dense white nodules of calcification are present on either valve surface. The valve here has been opened with the aortic outflow above and the left ventricular myocardium below.