Pulmonary artery catheter detected in the coronary sinus on intraoperative transesophageal echocardiogram. Diagnosis?

摘要

A 58-year-old man underwent mitral valve replacement, tricuspid valve repair, and ascending aorta repair. A pulmonary artery catheter (PAC) was inserted, but transesophageal echocardiography failed to show the PAC in the right atrium: the PAC was traversing an enlarged coronary sinus (Fig. 1). Why? A persistent left superior vena cava (SVC) and agenesis of the right SVC was found. This is a very rare anomaly: the incidence of persistent left SVC is 0.3-0.5 %, and only 18 % of individuals with persistent left SVC also have right SVC agenesis. In 92 % of cases the persistent left SVC drains into the right atrium via the coronary sinus, causing dilation. Coexistent right SVC agenesis further dilates the coronary sinus because of increased venous return [1].