沿着二尖瓣的闭锁缘可见一些小的疣状赘生物，它们与急性风湿热相关。这些疣状赘生物平均仅几个毫米，沿着心内膜炎症区上的瓣膜闭锁缘形成。这种赘生物小不至于引起严重的心脏疾病。
The small verrucous vegetations seen along the closure line of this mitral valve are associated with acute rheumatic fever. These warty vegetations average only a few millimeters and form along the line of valve closure over areas of endocardial inflammation. Such verrucae are too small to cause serious cardiac problems.