Isolated Accessory Tricuspid Valve Leaflet in Asymptomatic
Adult
Case presentation: A 40-year-old male patient presented with
level I trauma after a self-inflicted gunshot wound to the head. The
patient was declared brain dead, and a transesophageal echocardiogram
(TEE) was performed for consideration of organ harvest. TEE showed a
long (>4 cm) highly mobile accessory chord arising from the
subvalvular region of the septal tricuspid valve leaflet that traverses
the right ventricular outflow tract (RVOT) and the pulmonic valve with
no obstruction of the flow, most consistent with accessory tricuspid
valve (ATV) leaflet and no other anomalies were detected on the TEE
(Figure 1 and Videos 1,2, and 3).
Discussion: ATV is a rare congenital cardiac anomaly that is
often observed in complex congenital anomalies in children. However, it
has been reported in asymptomatic adults and to our knowledge, only two
cases of ATV in asymptomatic adults have been reported in the
literature. ATV is classified into ‘mobile’ or ‘fixed’ types. Mobile
type is tethered by long chordae which freely floats in the right
ventricle with a potential for RVOT obstruction. Fixed type is anchored
to interventricular septum by short chordae with a potential for VSD
obstruction if present. Papillary fibroelastoma is an important imaging
differential diagnosis to consider, as it can cause embolization that is
linked directly to its size and mobility. However, it is unclear if the
same applies to ATV. Although a definitive diagnosis of ATV is done
through surgical excision with histopathological analysis, cardiac
imaging is a cornerstone for making a diagnosis. Our case illustrates
key echocardiographic findings of an isolated ATV anomaly in absence of
coexisting complex anomalies.