A 19-year-old man was admitted for severe traumatic tricuspid regurgitation (TR) 4 months after a traffic accident. Transthoracic echocardiography revealed severe TR, with an abnormal chordal structure. Three-dimensional echocardiography showed widely lacerated right ventricular endocardium involving many subvalvular components. In this case of traumatic TR, three-dimensional echocardiography was useful not only for its diagnosis but also in providing important information for surgical decision making.
Case Presentation
A 19-year-old man was hit by a motor vehicle while riding on a motorcycle. He hit his head and chest strongly on the ground and was taken to the emergency room of a local hospital. He did not show any bleeding. On auscultation, a subtle pansystolic murmur was noted. Other results of the physical examination were unremarkable. The patient’s electrocardiogram demonstrated complete right bundle branch block, which had not been noted previously. His head and chest x-ray showed no signs of bone fracture. Transthoracic echocardiography (TTE) revealed mild tricuspid regurgitation (TR) without any sign of heart failure. Shortly thereafter, the patient was discharged.
Four months later, he began to complain of dyspnea on mild exertion, and TTE showed severe TR and an enlarged right ventricle. Diuretics were prescribed, but his symptoms did not improve. He was referred to our hospital for further treatment of severe TR.
On admission, his blood pressure and heart rate were 110/80 mm Hg and 80 beats/min, respectively. A prominent v wave was observed in his jugular vein. A grade 2/6 pansystolic murmur was present predominantly at the lower left sternal border, and a fourth heart sound was auscultated. The patient had no abnormalities in his abdomen or extremities. All laboratory results were normal, but the level of plasma brain natriuretic peptide was increased to 62.5 pg/mL (normal range, <20.0 pg/mL).
TTE revealed severe TR, and all 3 leaflets of the tricuspid valve were prolapsed. The TR pressure gradient was about 10 mm Hg. We found an abnormal chordal structure arising from the right ventricular (RV) septal wall and leading to the anterior and posterior leaflets of the tricuspid valve ( Figure 1 A). From the RV inflow view, this chordal structure looked like abnormal chordae tendineae ( Video 1 ). The patient’s left ventricle preserved its function but was deformed in diastole, compressed by the dilated right ventricle ( Figure 1 B).
We performed three-dimensional echocardiography to examine the abnormal chordal structure in more detail. The chordal structure arose from the wide area of the RV septal and posterior wall and led to the anterior and posterior tricuspid leaflets ( Figure 2 A, Video 2 ). A part of this chordal structure resembled septal myocardium. Around this chordal structure, we observed many subvalvular components, such as chordae tendineae and papillary muscles ( Figure 2 B, Video 3 ). None of the 3 leaflets of the tricuspid valve seemed to be damaged.
Because the patient’s clinical symptoms worsened even after oral medications and his right heart was enlarged, we thought that his tricuspid valve insufficiency should be corrected operatively. He underwent surgery 9 months after the accident. The endocardium of his RV septum was detached widely, including the papillary muscle and the subvalvular components ( Figure 3 ). Because of this myocardial laceration, the papillary muscle and chordae tendineae did not function normally, and all 3 leaflets of the tricuspid valve were prolapsed. The abnormal funicular structure observed on preoperative echocardiography was RV endocardial laceration and subvalvular components including the papillary muscle.
