Discussion
We presented the case of a car driver who sustained chest-wall trauma and then developed severe TR due to tricuspid valve leaflet perforation and annulus dilatation after blunt trauma. The mechanism of tricuspid valve injury is still controversial. Anatomically, the right ventricle is likely to have vulnerability to blunt trauma due to increased hydrostatic pressure by anteroposterior compression from the adjacent sternum7. When a deceleration force especially during the end-diastolic phase is transmitted through the ventricle, a forceful regurgitant blood flow can cause the rupture of a papillary muscle or of the chordae tendineae8. Delayed valvular rupture or avulsion may occur due to papillary muscle contusion with hemorrhage, inflammation, and late necrosis, leading to disruption over time6. If the damage is severe, symptomatic clinical deterioration and hemodynamic compromise can result. Blunt chest-wall trauma during high-speed motor vehicle accidents is common; however, valvular rupture or perforation is rare (less than 1%) and may present late9,10 which is similar to our case worsening progressively and causing severe TR later.
In our case, TR had been monitored and managed appropriately ,however, etiology of TR was not clear. The etiology of TR may be missed by 2-Dimentional(2-D) imaging and 3-Dimentional (3-D) TEE may provide definitive anatomic evaluation of the tricuspid apparatus for treatment planning11. As was seen in our patient, damage to tricuspid valve leaflet was missed on 2-D imaging which only showed annual dilatation and severe TR. Intraoperative 3-D echocardiographic imaging was able to show detailed anatomical and functional evaluation of the tricuspid apparatus.
Generally, tricuspid valve repair is preferable to valve replacement9,11. Whether to perform early surgery in patients who have sustained severe traumatic TR is still controversial. Traumatic TR is amenable to reparative techniques; however, delayed presentation impairs the success of surgical repair12. Particularly in patients who present late, surgical findings include contracted and atrophic papillary muscles, chordae, and valve leaflets5. Performing surgery before right ventricular dysfunction occurs will enhance the possibility of an adequate result and the subsequent maintenance of sinus rhythm12. In this case, complex anatomical valve dysfunction confirmed by intraoperative TEE allowed a decision for valve replacement.