FCN3 and cardiovascular disorder: Studies have shown that the reduction of serum ficolin-3 levels has a close bearing on a variety of cardiovascular diseases.3 According to foreign studies on Bulgarian and Norwegian races, ficolin-3 is associated with heart failure,4 but few studies have been carried out in China on ficolin-3 in heart failure, and most of the studies on ficolin-3 have focused on autoimmune system and inflammation and other diseases.