Excessive movement of the coronary sinus lead of CRT-D and severe tricuspid regurgitation

A 24-year-old male patient who had a cardiac resynchronization therapy device (CRT-D) implanted 2 years prior was admitted to our clinic with bilateral pretibial edema and abdominal ascites. Transthoracic echocardiography showed severe decreased left ventricular systolic function with an ejection fraction of 20% and mild-to-moderate mitral regurgitation. In addition, in the transthoracic echocardiography modified apical 4-chamber view, the coronary sinus (CS) lead of CRT-D showed excessive movement and it was acrossed the tricuspid inflow, and severe tricuspid regurgitation but without obstruction of the tricuspid valve closing was observed (Fig. 1a and 1b, Video 1 and 2). On modified parasternal short axis and 3-D image from the apical 4 chamber view, excessive movement of the CS lead was displayed (Fig. 1c and 1d, Video 3 and 4). Excessive movement of the lead toward the tricuspid inflow was seen during diastole, and tricuspid regurgitation was seen during sistole. Therefore, severe tricuspid regurgitation mechanism was not be caused by CS lead, and the patient had been followed up by medical treatment.