Introduction
The aortic valve (AV) is a semilunar valve and is derived from
endocardial cushions of the primitive heart tube. The right and left
cusps stem from conotruncal cushions, whereas the non-coronary cusp
originates from right-posterior intercalated cushions. Cavitation of the
cushions leads to separation of the cusps with formation of a lumen, and
this is followed by elongation and thinning of the cusps. Dysregulation
of extracellular matrix remodeling for instance, can lead to valve
malformations, and thus different valve phenotypes 1.
The normal AV-phenotype is tricuspid, but we know that AVs can range
from unicuspid (UAV) to quadricuspid valves, with even further
variability beyond this spectrum 2. Nonetheless, UAVs
are rare congenital heart valve malformations, with an estimated
prevalence of 0.02% 3. Although there is no official
classification for UAVs, possibly due to its’ rarity, we generally
distinguish between an acommissural- and unicommissural phenotype(Figure1A,B) .
UAVs can be repaired through biscuspidization. This is generally
achieved through patch augmentation of both cusps (e.g. butterfly
patch), with or without realignment of the commissural angle or aortic
annuloplasty 4, 5. As in other AV-phenotypes, there is
a spectrum of UAV morphologies. However, the commissure is usually
positioned posteriorly (Figure1B) and the height of the two raphae is
generally lower (5-15mm) than the level of the commissure6, as in bicuspid AVs 6, 7.
Nonetheless, there is no one technique fits all approach for UAV-repair,
and herein we are presenting our original technique for bicuspidization
of a regurgitant UAV without the usual patch augmentation of the cusps.